National Library of Energy BETA

Sample records for airborne high spectral

  1. 7 Plots of Biomass Burning and Dust Plumes This supplementary section shows curtain plots from the NASA Langley airborne High Spectral Resolution Lidar for

    E-Print Network [OSTI]

    Meskhidze, Nicholas

    7 Plots of Biomass Burning and Dust Plumes This supplementary section shows curtain plots from the NASA Langley airborne High Spectral Resolution Lidar for cases of fresh biomass burning plumes and dust: Curtain plots of HSRL backscatter coefficients and intensive properties for transects over fresh biomass

  2. Comparison of Mixed Layer Heights from Airborne High Spectral Resolution Lidar, Ground-based Measurements, and the WRP-Chem Model during CalNex and CARES

    SciTech Connect (OSTI)

    Scarino, Amy Jo; Obland, Michael; Fast, Jerome D.; Burton, S. P.; Ferrare, R. A.; Hostetler, Chris A.; Berg, Larry K.; Lefer, Barry; Haman, C.; Hair, John; Rogers, Ray; Butler, Carolyn; Cook, A. L.; Harper, David

    2014-06-05

    The California Research at the Nexus of Air Quality and Climate Change (CalNex) and Carbonaceous Aerosol and Radiative Effects Study (CARES) field campaigns during May and June 2010 provided a data set appropriate for studying characteristics of the planetary boundary layer (PBL). The NASA Langley Research Center (LaRC) airborne High Spectral Resolution Lidar (HSRL) was deployed to California onboard the NASA LaRC B-200 aircraft to aid incharacterizing aerosol properties during these two field campaigns. Measurements of aerosol extinction (532 nm), backscatter (532 and 1064 nm), and depolarization (532 and 1064 nm) profiles during 31 flights, many in coordination with other research aircraft and ground sites, constitute a diverse data set for use in characterizing the spatial and temporal distribution of aerosols, as well as the depth and variability of the daytime mixed layer (ML), which is a subset within the PBL. This work illustrates the temporal and spatial variability of the ML in the vicinity of Los Angeles and Sacramento, CA. ML heights derived from HSRL measurements are compared to PBL heights derived from radiosonde profiles, ML heights measured from ceilometers, and simulated PBL heights from the Weather Research and Forecasting Chemistry (WRF-Chem) community model. Comparisons between the HSRL ML heights and the radiosonde profiles in Sacramento result in a correlation coefficient value (R) of 0.93 (root7 mean-square (RMS) difference of 157 m and bias difference (HSRL radiosonde) of 5 m). HSRL ML heights compare well with those from the ceilometer in the LA Basin with an R of 0.89 (RMS difference of 108 m and bias difference (HSRL Ceilometer) of -9.7 m) for distances of up to 30 km between the B-200 flight track and the ceilometer site. Simulated PBL heights from WRF-Chem were compared with those obtained from all flights for each campaign, producing an R of 0.58 (RMS difference of 604 m and a bias difference (WRF-Chem HSRL) of -157 m) for CalNex and 0.59 (RMS difference of 689 m and a bias difference (WRF-Chem HSRL) of 220 m) for CARES. Aerosol backscatter simulations are also available from WRF15 Chem and are compared to those from HSRL to examine differences among the methods used to derive ML heights.

  3. Airborne Multiwavelength High-Spectral-Resolution Lidar (HSRL-2) Observations During TCAP 2012: Vertical Proles of Optical and Microphysical Properties of a Smoke/Urban Haze Plume Over the Northeastern Coast of the US

    SciTech Connect (OSTI)

    Muller, Detlef; Hostetler, Chris A.; Ferrare, R. A.; Burton, S. P.; Chemyakin, Eduard; Kolgotin, A.; Hair, John; Cook, A. L.; Harper, David; Rogers, R. R.; Hare, Rich; Cleckner, Craig; Obland, Michael; Tomlinson, Jason M.; Berg, Larry K.; Schmid, Beat

    2014-10-10

    We present rst measurements with the rst airborne multiwavelength High-Spectral Resolution Lidar (HSRL-2), developed by NASA Langley Research Center. The instrument was operated during the Department of Energy (DOE) Two-Column Aerosol Project (TCAP) in July 2012. We observed out ow of urban haze and fresh biomass burning smoke from the East Coast of the US out over the West Atlantic Ocean. Lidar ratios at 355 and 532 nm were ... sr indicating moderately absorbing aerosols. Extinctionrelated Angstrom exponents were 1.5{2 pointing at comparably small particles. Our novel automated, unsupervised data inversion algorithm retrieves particle e*ective radii of approximately 0.2 *m, which is in agreement with the large Angstrom exponents. We nd reasonable agreement to particle size parameters obtained from situ measurements carried out with the DOE G-1 aircraft that ew during the lidar observations.

  4. In this paper, we evaluate the capability of the high spatial resolution airborne Digital Airborne Imaging System (DAIS)

    E-Print Network [OSTI]

    Yu, Qian

    with the aid of ancillary topographic data. Image objects as minimum classification units were generatedAbstract In this paper, we evaluate the capability of the high spatial resolution airborne Digital Airborne Imaging System (DAIS) imagery for detailed vegetation classification at the alliance level

  5. High-performance computing for airborne applications

    SciTech Connect (OSTI)

    Quinn, Heather M; Manuzzato, Andrea; Fairbanks, Tom; Dallmann, Nicholas; Desgeorges, Rose

    2010-06-28

    Recently, there has been attempts to move common satellite tasks to unmanned aerial vehicles (UAVs). UAVs are significantly cheaper to buy than satellites and easier to deploy on an as-needed basis. The more benign radiation environment also allows for an aggressive adoption of state-of-the-art commercial computational devices, which increases the amount of data that can be collected. There are a number of commercial computing devices currently available that are well-suited to high-performance computing. These devices range from specialized computational devices, such as field-programmable gate arrays (FPGAs) and digital signal processors (DSPs), to traditional computing platforms, such as microprocessors. Even though the radiation environment is relatively benign, these devices could be susceptible to single-event effects. In this paper, we will present radiation data for high-performance computing devices in a accelerated neutron environment. These devices include a multi-core digital signal processor, two field-programmable gate arrays, and a microprocessor. From these results, we found that all of these devices are suitable for many airplane environments without reliability problems.

  6. AIRBORNE HIGH SPECTRAL RESOLUTION LIDAR MEASUREMENTS OF ATMOSPHERIC AEROSOLS

    E-Print Network [OSTI]

    the evolution and transport of pollution from Mexico City. The second major experiment was the Texas Air Quality, A., University of Hawaii, Department of Oceanography University of Hawaii, Honolulu, HI 96822 Air B200 aircraft during several field experiments. Most of the flights were conducted during two

  7. EVALUATION OF AIRBORNE AND SATELLITE ELECTRO-OPTICAL SENSORS PERFORMANCES BY USE OF HIGH-ALTITUDE CLOUDS OCCURRENCE

    E-Print Network [OSTI]

    EVALUATION OF AIRBORNE AND SATELLITE ELECTRO-OPTICAL SENSORS PERFORMANCES BY USE OF HIGH, F-91761 Palaiseau, France, email : karine.caillault@onera.fr KEYWORDS: sensor performance require optronic sensors, onboard satellite or airborne platform. Performances limitation of these sensors

  8. Final Report: High Spectral Resolution Atmospheric Emitted Radiance Studies with the ARM UAV

    SciTech Connect (OSTI)

    Revercomb, Henry E.

    1999-12-31

    The active participation in the Atmospheric Radiation Measurement (ARM) Unmanned Airborne Vehicle (UAV) science team that was anticipated in the grant proposal was indefinitely delayed after the first year due to a programmatic decision to exclude the high spectral resolution observations from the existing ARM UAV program. However, this report shows that substantial progress toward the science objectives of this grant have made with the help of separate funding from NASA and other agencies. In the four year grant period (including time extensions), a new high spectral resolution instrument has been flown and has successfully demonstrated the ability to obtain measurements of the type needed in the conduct of this grant. In the near term, the third water vapor intensive observing period (WVIOP-3) in October 2000 will provide an opportunity to bring the high spectral resolution observations of upwelling radiance into the ARM program to complement the downwelling radiance observations from the existing ARM AERI instruments. We look forward to a time when the ARM-UAV program is able to extend its scope to include the capability for making these high spectral resolution measurements from a UAV platform.

  9. High Performance Computing with a Conservative Spectral Boltzmann Solver

    E-Print Network [OSTI]

    High Performance Computing with a Conservative Spectral Boltzmann Solver Jeffrey R. Haack and Irene the structure of the collisional formulation for high performance computing environments. The locality in space on high performance computing resources. We also use the improved computational power of this method

  10. Characterizing Aerosol Distributions and Optical Properties Using the NASA Langley High Spectral Resolution Lidar

    SciTech Connect (OSTI)

    Hostetler, Chris; Ferrare, Richard

    2013-02-14

    The objective of this project was to provide vertically and horizontally resolved data on aerosol optical properties to assess and ultimately improve how models represent these aerosol properties and their impacts on atmospheric radiation. The approach was to deploy the NASA Langley Airborne High Spectral Resolution Lidar (HSRL) and other synergistic remote sensors on DOE Atmospheric Science Research (ASR) sponsored airborne field campaigns and synergistic field campaigns sponsored by other agencies to remotely measure aerosol backscattering, extinction, and optical thickness profiles. Synergistic sensors included a nadir-viewing digital camera for context imagery, and, later in the project, the NASA Goddard Institute for Space Studies (GISS) Research Scanning Polarimeter (RSP). The information from the remote sensing instruments was used to map the horizontal and vertical distribution of aerosol properties and type. The retrieved lidar parameters include profiles of aerosol extinction, backscatter, depolarization, and optical depth. Products produced in subsequent analyses included aerosol mixed layer height, aerosol type, and the partition of aerosol optical depth by type. The lidar products provided vertical context for in situ and remote sensing measurements from other airborne and ground-based platforms employed in the field campaigns and was used to assess the predictions of transport models. Also, the measurements provide a data base for future evaluation of techniques to combine active (lidar) and passive (polarimeter) measurements in advanced retrieval schemes to remotely characterize aerosol microphysical properties. The project was initiated as a 3-year project starting 1 January 2005. It was later awarded continuation funding for another 3 years (i.e., through 31 December 2010) followed by a 1-year no-cost extension (through 31 December 2011). This project supported logistical and flight costs of the NASA sensors on a dedicated aircraft, the subsequent analysis and archival of the data, and the presentation of results in conferences, workshops, and publications. DOE ASR field campaigns supported under this project included - MAX-Mex /MILAGRO (2006) - TexAQS 2006/GoMACCS (2006) - CHAPS (2007) - RACORO (2009) - CARE/CalNex (2010) In addition, data acquired on HSRL airborne field campaigns sponsored by other agencies were used extensively to fulfill the science objectives of this project and the data acquired have been made available to other DOE ASR investigators upon request.

  11. Abstract--Airborne pollution and explosive gases threaten human health and occupational safety, therefore generating high

    E-Print Network [OSTI]

    Mason, Andrew

    Abstract--Airborne pollution and explosive gases threaten human health and occupational safety and a thumb-drive sized prototype system. I. INTRODUCTION xposure to air pollution consistently ranks among to occupational safety as energy demands rise. Airborne pollutants and explosive gases vary in both time and space

  12. Transport and spectral functions in high-temperature QCD

    E-Print Network [OSTI]

    Gert Aarts

    2007-10-03

    The current status of transport coefficients in relativistic field theories at high temperature is reviewed. I contrast weak coupling results obtained using kinetic theory/diagrammatic techniques with strong coupling results obtained using gauge/gravity duality, and describe the recent developments in extracting transport coefficients and spectral functions from lattice QCD simulations. The fate of quarkonium at high temperature as seen from the lattice is briefly mentioned as well.

  13. Spectral function at high missing energies and momenta

    E-Print Network [OSTI]

    T. Frick; Kh. S. A. Hassaneen; D. Rohe; H. Müther

    2004-06-03

    The nuclear spectral function at high missing energies and momenta has been determined from a self-consistent calculation of the Green's function in nuclear matter using realistic nucleon-nucleon interactions. The results are compared with recent experimental data derived from ($e,e'p$) reactions on $^{12}C$. A rather good agreement is obtained if the Green's functions are calculated in a non-perturbative way.

  14. AIRBORNE HIGH SPECTRAL RESOLUTION LIDAR AEROSOL MEASUREMENTS DURING CALNEX AND CARES

    E-Print Network [OSTI]

    , and Evgueni Kassianov, Pacific Northwest National Laboratory Brent Holben, NASA Goddard Space Flight Center National Laboratory U.S. Department of Energy Office of Science ABSTRACT The NASA Langley Research Center layers of dust, likely transported from Asia, were located above urban aerosols. HSRL and ground- based

  15. Diagnostics of Ellerman Bombs with High-resolution Spectral Data

    E-Print Network [OSTI]

    Li, Z; Guo, Y; Chen, P F; Xu, Z; Cao, W

    2015-01-01

    Ellerman bombs (EBs) are tiny brightenings often observed near sunspots. The most impressive characteristic of the EB spectra is the two emission bumps in both wings of the H$\\alpha$ and \\ion{Ca}{II} 8542 {\\AA} lines. High-resolution spectral data of three small EBs were obtained on 2013 June 6 with the largest solar telescope, the 1.6 meter New Solar Telescope (NST), at the Big Bear Solar Observatory. The characteristics of these EBs are analyzed. The sizes of the EBs are in the range of 0.3\\arcsec\\--0.8\\arcsec\\ and their durations are only 3--5 minutes. Our semi-empirical atmospheric models indicate that the heating occurs around the temperature minimum region with a temperature increase of 2700--3000 K, which is surprisingly higher than previously thought. The radiative and kinetic energies are estimated to be as high as 5$\\times$10$^{25}$--3.0$\\times$10$^{26}$ ergs despite the small size of these EBs. Observations of the magnetic field show that the EBs appeared just in a parasitic region with mixed polar...

  16. High-efficiency spectral purity filter for EUV lithography

    DOE Patents [OSTI]

    Chapman, Henry N. (Livermore, CA)

    2006-05-23

    An asymmetric-cut multilayer diffracts EUV light. A multilayer cut at an angle has the same properties as a blazed grating, and has been demonstrated to have near-perfect performance. Instead of having to nano-fabricate a grating structure with imperfections no greater than several tens of nanometers, a thick multilayer is grown on a substrate and then cut at an inclined angle using coarse and inexpensive methods. Effective grating periods can be produced this way that are 10 to 100 times smaller than those produced today, and the diffraction efficiency of these asymmetric multilayers is higher than conventional gratings. Besides their ease of manufacture, the use of an asymmetric multilayer as a spectral purity filter does not require that the design of an EUV optical system be modified in any way, unlike the proposed use of blazed gratings for such systems.

  17. SPEAR far UV spectral imaging of highly ionized emission from the North Galactic Pole Region

    E-Print Network [OSTI]

    B. Y. Welsh; J. Edelstein; E. Korpela

    2007-06-06

    We present far ultraviolet (FUV: 912 - 1750AA) spectral imaging observations recorded with the SPEAR satellite of the interstellar OVI (1032AA), CIV (1550AA), SiIV (1394AA), SiII* (1533AA) and AlII (1671AA) emission lines originating in a 60 x 30 degree rectangular region lying close to the North Galactic Pole. These data represent the first large area, moderate spatial resolution maps of the distribution of UV spectral-line emission originating the both the highly ionized medium (HIM) and the warm ionized medium (WIM) recorded at high galactic latitudes.

  18. Broadband high resolution X-ray spectral analyzer

    DOE Patents [OSTI]

    Silver, E.H.; Legros, M.; Madden, N.W.; Goulding, F.; Landis, D.

    1998-07-07

    A broad bandwidth high resolution X-ray fluorescence spectrometer has a performance that is superior in many ways to those currently available. It consists of an array of 4 large area microcalorimeters with 95% quantum efficiency at 6 keV and it produces X-ray spectra between 0.2 keV and 7 keV with an energy resolution of 7 to 10 eV. The resolution is obtained at input count rates per array element of 10 to 50 Hz in real-time, with analog pulse processing and thermal pile-up rejection. This performance cannot be matched by currently available X-ray spectrometers. The detectors are incorporated into a compact and portable cryogenic refrigerator system that is ready for use in many analytical spectroscopy applications as a tool for X-ray microanalysis or in research applications such as laboratory and astrophysical X-ray and particle spectroscopy. 6 figs.

  19. High Spectral Resolution Infrared and Raman Lidar Observations for the ARM Program: Clear and Cloudy Sky Applications

    SciTech Connect (OSTI)

    Henry Revercomb, David Tobin, Robert Knuteson, Lori Borg, Leslie Moy

    2009-06-17

    This grant began with the development of the Atmospheric Emitted Radiance Interferometer (AERI) for ARM. The AERI has provided highly accurate and reliable observations of downwelling spectral radiance (Knuteson et al. 2004a, 2004b) for application to radiative transfer, remote sensing of boundary layer temperature and water vapor, and cloud characterization. One of the major contributions of the ARM program has been its success in improving radiation calculation capabilities for models and remote sensing that evolved from the multi-year, clear-sky spectral radiance comparisons between AERI radiances and line-by-line calculations (Turner et al. 2004). This effort also spurred us to play a central role in improving the accuracy of water vapor measurements, again helping ARM lead the way in the community (Turner et al. 2003a, Revercomb et al. 2003). In order to add high-altitude downlooking AERI-like observations over the ARM sites, we began the development of an airborne AERI instrument that has become known as the Scanning High-resolution Interferometer Sounder (Scanning-HIS). This instrument has become an integral part of the ARM Unmanned Aerospace Vehicle (ARM-UAV) program. It provides both a cross-track mapping view of the earth and an uplooking view from the 12-15 km altitude of the Scaled Composites Proteus aircraft when flown over the ARM sites for IOPs. It has successfully participated in the first two legs of the “grand tour” of the ARM sites (SGP and NSA), resulting in a very good comparison with AIRS observations in 2002 and in an especially interesting data set from the arctic during the Mixed-Phase Cloud Experiment (M-PACE) in 2004. More specifically, our major achievements for ARM include 1. Development of the Atmospheric Emitted Radiance Interferometer (AERI) to function like a satellite on the ground for ARM, providing a steady stream of accurately calibrated spectral radiances for Science Team clear sky and cloud applications (Knuteson et al. 2004a), 2. Detailed radiometric calibration and characterization of AERI radiances, with uncertainty estimates established from complete error analyses and proven by inter-comparison tests (Knuteson et al. 2004b), 3. AERI data quality assessment and maintenance over the extended time frames needed to support ARM (Dedecker et al., 2005) 4. Key role in the radiative transfer model improvements from the AERI/LBLRTM QME (Turner et al. 2004) and AERI-ER especially from the SHEBA experiment (Tobin et al. 1999), 5. Contributed scientific and programmatic leadership leading to significant water vapor accuracy improvements and uncertainty assessments for the low to mid troposphere (Turner et al. 2003a, Revercomb et al. 2003), 6. Leadership of the ARM assessment of the accuracy of water vapor observations from radiosondes, Raman Lidar and in situ aircraft observations in the upper troposphere and lower stratosphere (Tobin et al. 2002, Ferrare et al. 2004), 7. New techniques for characterizing clouds from AERI (DeSlover et al. 1999, Turner 2003b, Turner et al. 2003b), 8. Initial design and development of the Scanning-HIS aircraft instrument and application to ARM UAV Program missions (Revercomb et al. 2005), and 9. Coordinated efforts leading to the use of ARM observations as a key validation tool for the high resolution Atmospheric IR Sounder on the NASA Aqua platform (Tobin et al. 2005a) 10. Performed ARM site and global clear sky radiative closure studies that shows closure of top-of-atmosphere flux at the level of ~1 W/m2 (Moy et al 2008 and Section 3 of this appendix) 11. Performed studies to characterize SGP site cirrus cloud property retrievals and assess impacts on computed fluxes and heating rate profiles (Borg et al. 2008 and Section 2 of this appendix).

  20. Adaptive-feedback spectral-phase control for interactions with transform-limited ultrashort high-power laser pulses

    E-Print Network [OSTI]

    Umstadter, Donald

    point of a 100-TW peak-power laser in vacuum. The spectral-phase distortion induced by the dispersion that use high-power laser pulses must be performed in vacuum in order to prevent degradation of the laserAdaptive-feedback spectral-phase control for interactions with transform-limited ultrashort high-power

  1. Structure of W3(OH) from Very High Spectral Resolution Observations of 5 Centimeter OH Masers

    E-Print Network [OSTI]

    Vincent L. Fish; Loránt O. Sjouwerman

    2007-06-22

    Recent studies of methanol and ground-state OH masers at very high spectral resolution have shed new light on small-scale maser processes. The nearby source W3(OH), which contains numerous bright masers in several different transitions, provides an excellent laboratory for high spectral resolution techniques. We present a model of W3(OH) based on EVN observations of the rotationally-excited 6030 and 6035 MHz OH masers taken at 0.024 km/s spectral resolution. The 6.0 GHz masers are becoming brighter with time and show evidence for tangential proper motions. We confirm the existence of a region of magnetic field oriented toward the observer to the southeast and find another such region to the northeast in W3(OH), near the champagne flow. The 6.0 GHz masers trace the inner edge of a counterclockwise rotating torus feature. Masers at 6030 MHz are usually a factor of a few weaker than at 6035 MHz but trace the same material. Velocity gradients of nearby Zeeman components are much more closely correlated than in the ground state, likely due to the smaller spatial separation between Zeeman components. Hydroxyl maser peaks at very long baseline interferometric resolution appear to have structure on scales both smaller than that resolvable as well as on larger scales.

  2. Spectral analysis of the high-energy IceCube neutrinos

    E-Print Network [OSTI]

    Palomares-Ruiz, Sergio; Mena, Olga

    2015-01-01

    A full energy and flavor-dependent analysis of the three-year high-energy IceCube neutrino events is presented. By means of multi-dimensional fits, we derive the current preferred values of the high-energy neutrino flavor ratios, the normalization and spectral index of the astrophysical fluxes, and the expected atmospheric background events, including a prompt component. A crucial assumption resides on the choice of the energy interval used for the analyses, which significantly biases the results. When restricting ourselves to the $\\sim$30 TeV - 3 PeV energy range, which contains all the observed IceCube events, we find that the inclusion of the spectral information improves the fit to the canonical flavor composition at Earth, ($1:1:1$)$_\\oplus$, with respect to a single-energy bin analysis. Increasing both the minimum and the maximum deposited energies has dramatic effects on the reconstructed flavor ratios as well as on the spectral index. Imposing a higher threshold of 60 TeV yields a slightly harder spec...

  3. Spectral Evolution of Two High-Energy Gamma-Ray Bursts

    E-Print Network [OSTI]

    Y. Kaneko; R. D. Preece; M. M. Gonzalez; B. L. Dingus; M. S. Briggs

    2004-01-15

    The prompt emission of the gamma-ray bursts is found to be very energetic, releasing ~10^51 ergs in a flash. However, their emission mechanism remains unclear and understanding their spectra is a key to determining the emission mechanism. Many GRB spectra have been analyzed in the sub-MeV energy band, and are usually well described with a smoothly broken power-law model. We present a spectral analysis of two bright bursts (GRB910503 and GRB930506), using BATSE and EGRET spectra that cover more than four decades of energy (30 keV - 200 MeV). Our results show time evolutions of spectral parameters (low-energy & high-energy photon indices and break energy) that are difficult to reconcile with a simple shock-acceleration model.

  4. Spectral Evolution of Two High-Energy Gamma-Ray Bursts

    E-Print Network [OSTI]

    Kaneko, Y; Dingus, B L; González, M M; Preece, R D

    2004-01-01

    The prompt emission of the gamma-ray bursts is found to be very energetic, releasing ~10^51 ergs in a flash. However, their emission mechanism remains unclear and understanding their spectra is a key to determining the emission mechanism. Many GRB spectra have been analyzed in the sub-MeV energy band, and are usually well described with a smoothly broken power-law model. We present a spectral analysis of two bright bursts (GRB910503 and GRB930506), using BATSE and EGRET spectra that cover more than four decades of energy (30 keV - 200 MeV). Our results show time evolutions of spectral parameters (low-energy & high-energy photon indices and break energy) that are difficult to reconcile with a simple shock-acceleration model.

  5. Observation of spectral gain narrowing in a high-order harmonic seeded soft-x-ray amplifier

    SciTech Connect (OSTI)

    Tissandier, F.; Sebban, S.; Ribiere, M.; Gautier, J.; Zeitoun, Ph.; Lambert, G.; Barszczak Sardinha, A.; Goddet, J.-Ph.; Burgy, F.; Lefrou, T.; Valentin, C.; Rousse, A.; Guilbaud, O.; Klisnick, A.; Nejdl, J.; Mocek, T.; Maynard, G. [Laboratoire d'Optique Appliquee, ENSTA Paristech/Ecole Polytechnique/CNRS UMR 7639, F-91761 Palaiseau Cedex (France); Laboratoire d'Interaction du Rayonnement X Avec la Matiere, Universite Paris Sud/CNRS UMR 8624, F-91495 Orsay Cedex (France); Department of X-ray Lasers, Institute of Physics, Na Slovance 2, CZ-182 21 Prague 8 (Czech Republic); Laboratoire de Physique des Gaz et des Plasmas, Universite Paris Sud/CNRS UMR 8578, F-91405 Orsay Cedex (France)

    2010-06-15

    We report an observation of spectral gain narrowing of a high-order harmonic amplified by a soft-x-ray optical-field-ionized plasma. The temporal coherence and spectral linewidth of both the seeded and unseeded soft-x-ray lasers were experimentally measured using a varying-path-difference interferometer. The results showed that the high-order harmonic is subject to a strong spectral narrowing during its propagation in the plasma amplifier without rebroadening at saturation. This is in good agreement with a radiative transfer calculation including gain narrowing and saturation rebroadening.

  6. Active airborne contamination control using electrophoresis

    SciTech Connect (OSTI)

    Veatch, B.D.

    1994-06-01

    In spite of our best efforts, radioactive airborne contamination continues to be a formidable problem at many of the Department of Energy (DOE) weapons complex sites. For workers that must enter areas with high levels of airborne contamination, personnel protective equipment (PPE) can become highly restrictive, greatly diminishing productivity. Rather than require even more restrictive PPE for personnel in some situations, the Rocky Flats Plant (RFP) is actively researching and developing methods to aggressively combat airborne contamination hazards using electrophoretic technology. With appropriate equipment, airborne particulates can be effectively removed and collected for disposal in one simple process. The equipment needed to implement electrophoresis is relatively inexpensive, highly reliable, and very compact. Once airborne contamination levels are reduced, less PPE is required and a significant cost savings may be realized through decreased waste and maximized productivity. Preliminary ``cold,`` or non-radioactive, testing results at the RFP have shown the technology to be effective on a reasonable scale, with several potential benefits and an abundance of applications.

  7. An eigen-based high-order expansion basis for structured spectral ...

    E-Print Network [OSTI]

    X. Zheng

    2011-09-17

    Aug 26, 2011 ... has been very successful in computational fluid dynamics (CFD). ...... [21] A.T. Patera, A spectral method for fluid dynamics: laminar flow in a ...

  8. High-resolution single-shot spectral monitoring of hard x-ray free-electron laser radiation

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Makita, M.; Karvinen, P.; Zhu, D.; Juranic, P. N.; Grünert, J.; Cartier, S.; Jungmann-Smith, J. H.; Lemke, H. T.; Mozzanica, A.; Nelson, S.; et al

    2015-10-16

    We have developed an on-line spectrometer for hard x-ray free-electron laser (XFEL) radiation based on a nanostructured diamond diffraction grating and a bent crystal analyzer. Our method provides high spectral resolution, interferes negligibly with the XFEL beam, and can withstand the intense hard x-ray pulses at high repetition rates of >100 Hz. The spectrometer is capable of providing shot-to-shot spectral information for the normalization of data obtained in scientific experiments and optimization of the accelerator operation parameters. We have demonstrated these capabilities of the setup at the Linac Coherent Light Source, in self-amplified spontaneous emission mode at full energy ofmore »>1 mJ with a 120 Hz repetition rate, obtaining a resolving power of ?/?? > 3 × 104. In conclusion, the device was also used to monitor the effects of pulse duration down to 8 fs by analysis of the spectral spike width.« less

  9. Broadband Spectral Properties of Bright High-Energy Gamma-Ray Bursts Observed with BATSE and EGRET

    E-Print Network [OSTI]

    Kaneko, Y; Preece, R; Dingus, B L; Briggs, M S

    2008-01-01

    We present the spectral analysis of duration-integrated broadband spectra (in $\\sim30 $keV$-200 $MeV) of 15 bright BATSE gamma-ray bursts (GRBs). Some GRB spectra are very hard, with their spectral peak energies being above the BATSE LAD passband limit of $\\sim$2 MeV. In such cases, their high-energy spectral parameters (peak energy and high-energy power-law indices) cannot be adequately constrained by BATSE LAD data alone. A few dozen bright BATSE GRBs were also observed with EGRET's calorimeter, TASC, in multi-MeV energy band, with a large effective area and fine energy resolution. Combining the BATSE and TASC data, therefore, affords spectra that span four decades of energy ($30 $keV$-200 $MeV), allowing for a broadband spectral analysis with good statistics. Studying such broadband high-energy spectra of GRB prompt emission is crucial, as they provide key clues to understanding its gamma-ray emission mechanism. Among the 15 GRB spectra, we found two cases with a significant high-energy excess, and another...

  10. CLOUD FRACTION STATISTICS DERIVED FROM 2YEARS OF HIGH SPECTRAL RESOLUTION LIDAR DATA ACQUIRED AT EUREKA, CANADA.

    E-Print Network [OSTI]

    Eloranta, Edwin W.

    CLOUD FRACTION STATISTICS DERIVED FROM 2YEARS OF HIGH SPECTRAL RESOLUTION LIDAR DATA ACQUIRED(AHSRL) and the NOAA 8.6 mm wavelength cloud radar (MMCR). Both instruments have operated nearly continuously since Sept 2005. This paper presents a record of cloud cover, cloud altitude and cloud phase derived

  11. Running Spectral Index as a Probe of Physics at High Scales

    E-Print Network [OSTI]

    G. Ballesteros; J. A. Casas; J. R. Espinosa

    2006-03-23

    The WMAP results on the scalar spectral index n and its running with scale, though preliminary, open a very interesting window to physics at very high energies. We address the problem of finding inflaton potentials well motivated by particle physics which can accomodate WMAP data. We make a model independent analysis of a large class of models: those with flat tree-level potential lifted by radiative corrections, which cause the slow rolling of the inflaton and the running of n. This includes typical hybrid inflation models. In the small-coupling regime the predictions for the size and running of n are remarkably neat, e.g. -dn/dln k=(n-1)^2 price of having a small number of e-folds, Ne. We also examine the effect of mass thresholds crossed during inflation. Finally, we show that the presence of non-renormalizable operators for the inflaton, suppressed by a mass scale above the inflationary range, is able to give both dn/dln k ~ O(-0.05) and Ne ~ 50.

  12. Near-fault earthquake ground motion prediction by a high-performance spectral element numerical code

    SciTech Connect (OSTI)

    Paolucci, Roberto [Department of Structural Engineering, Politecnico di Milano P.za Leonardo da Vinci 32, 20133, Milano (Italy); Stupazzini, Marco [Department of Structural Engineering, Politecnico di Milano P.za Leonardo da Vinci 32, 20133, Milano (Italy); EUCENTRE, v. Ferrata 1, Pavia (Italy)

    2008-07-08

    Near-fault effects have been widely recognised to produce specific features of earthquake ground motion, that cannot be reliably predicted by 1D seismic wave propagation modelling, used as a standard in engineering applications. These features may have a relevant impact on the structural response, especially in the nonlinear range, that is hard to predict and to be put in a design format, due to the scarcity of significant earthquake records and of reliable numerical simulations. In this contribution a pilot study is presented for the evaluation of seismic ground-motions in the near-fault region, based on a high-performance numerical code for 3D seismic wave propagation analyses, including the seismic fault, the wave propagation path and the near-surface geological or topographical irregularity. For this purpose, the software package GeoELSE is adopted, based on the spectral element method. The set-up of the numerical benchmark of 3D ground motion simulation in the valley of Grenoble (French Alps) is chosen to study the effect of the complex interaction between basin geometry and radiation mechanism on the variability of earthquake ground motion.

  13. Broadband Spectral Properties of Bright High-Energy Gamma-Ray Bursts Observed with BATSE and EGRET

    E-Print Network [OSTI]

    Y. Kaneko; M. M. Gonzalez; R. Preece; B. L. Dingus; M. S. Briggs

    2008-01-12

    We present the spectral analysis of duration-integrated broadband spectra (in $\\sim30 $keV$-200 $MeV) of 15 bright BATSE gamma-ray bursts (GRBs). Some GRB spectra are very hard, with their spectral peak energies being above the BATSE LAD passband limit of $\\sim$2 MeV. In such cases, their high-energy spectral parameters (peak energy and high-energy power-law indices) cannot be adequately constrained by BATSE LAD data alone. A few dozen bright BATSE GRBs were also observed with EGRET's calorimeter, TASC, in multi-MeV energy band, with a large effective area and fine energy resolution. Combining the BATSE and TASC data, therefore, affords spectra that span four decades of energy ($30 $keV$-200 $MeV), allowing for a broadband spectral analysis with good statistics. Studying such broadband high-energy spectra of GRB prompt emission is crucial, as they provide key clues to understanding its gamma-ray emission mechanism. Among the 15 GRB spectra, we found two cases with a significant high-energy excess, and another case with a extremely high peak energy (\\epeak $\\gtrsim$ 170 MeV). There have been very limited number of GRBs observed at MeV energies and above, and only a few instruments have been capable of observing GRBs in this energy band with such high sensitivity. Thus, our analysis results presented here should also help predict GRB observations with current and future high-energy instruments such as AGILE and GLAST, as well as with ground-based very-high-energy telescopes.

  14. Modelling the Spectral Energy Distribution of Compact Luminous Infrared Galaxies: Constraints from High Frequency Radio Data

    E-Print Network [OSTI]

    O. R. Prouton; A. Bressan; M. Clemens; A. Franceschini; G. L. Granato; L. Silva

    2004-03-24

    We have performed 23 GHz VLA observations of 7 compact, luminous infrared galaxies, selected to have evidence of starburst activity. New and published multi-frequency data are combined to obtain the spectral energy distributions of all 7 galaxies from the near-infrared to the radio (at 1.4 GHz). These SEDs are compared with new models, for dust enshrouded galaxies, which account for both starburst and AGN components. In all 7 galaxies the starburst provides the dominant contribution to the infrared luminosity; in 4 sources no contribution from an AGN is required. Although AGN may contribute up to 50 percent of the total far--infrared emission, the starbursts always dominate in the radio. The SEDs of most of our sources are best fit with a very high optical depth of (>=50) at 1 micron. The scatter in the far-infrared/radio correlation, found among luminous IRAS sources, is due mainly to the different evolutionary status of their starburst components. The short time-scale of the star formation process amplifies the delay between the far-infrared and radio emission. This becomes more evident at low radio frequencies (below about 1 GHz) where synchrotron radiation is the dominant process. In the far-infrared (at wavelengths shorter than 100 micron) an additional source of scatter is provided by AGN, where present. AGN may be detected in the near-infrared by the absence of the knee, typical of stellar photospheres. However, near-infrared data alone cannot constrain the level at which AGN contribute because the interpretation of their observed properties, in this wave-band, depends strongly on model parameters.

  15. Spectral lines and distribution of Hi in high rotational levels Dairene Uy, Charles M. Gabrys, Mary-Frances Jagod, and Takeshi Oka

    E-Print Network [OSTI]

    Oka, Takeshi

    Spectral lines and distribution of Hi in high rotational levels Dairene Uy, Charles M. Gabrys, Mary K in their simu- lation of the observed spectrum.) The first motive to study Hi in high rotational

  16. Airborne wireless communication systems, airborne communication methods, and communication methods

    DOE Patents [OSTI]

    Deaton, Juan D. (Menan, ID); Schmitt, Michael J. (Idaho Falls, ID); Jones, Warren F. (Idaho Falls, ID)

    2011-12-13

    An airborne wireless communication system includes circuitry configured to access information describing a configuration of a terrestrial wireless communication base station that has become disabled. The terrestrial base station is configured to implement wireless communication between wireless devices located within a geographical area and a network when the terrestrial base station is not disabled. The circuitry is further configured, based on the information, to configure the airborne station to have the configuration of the terrestrial base station. An airborne communication method includes answering a 911 call from a terrestrial cellular wireless phone using an airborne wireless communication system.

  17. High dynamic range measurement of spectral responsivity and linearity of a radiation thermometer using a super-continuum laser and LEDs

    SciTech Connect (OSTI)

    Yoo, Y. S.; Lee, D. H.; Park, C. W.; Park, S. N. [Korea Research Institute of Standards and Science 209 Gajeong-Ro, Yuseong-Gu, Daejon 305-340 (Korea, Republic of)] [Korea Research Institute of Standards and Science 209 Gajeong-Ro, Yuseong-Gu, Daejon 305-340 (Korea, Republic of)

    2013-09-11

    To realize the temperature scale above the freezing point of silver according to the definition of ITS-90, the dynamic range of the spectral responsivity is one of the most important factors which limit its uncertainty. When the residual spectral response at both side bands of a spectral band is not negligible, a significant uncertainty can be caused by a low dynamic range of the spectral responsivity measurement. In general, incandescent lamps are used to measure the spectral responsivity and the linearity. The dynamic range of the spectral responsivity measurement is often limited by a trade-off with the desired spectral resolution, which is less than 6 decades. Nonlinearity is another limiting fact of uncertainties of the temperature scale. Tungsten lamps have disadvantage in the nonlinearity measurements in terms of adjustability of radiance level and spectral selectivity. We report spectral responsivity measurements of which the measurable dynamic range is enhanced 50 times after replacing a QTH lamp with a super continuum laser. We also present a spectrally selected linearity measurement over a wide dynamic range using high-brightness light emitting diode arrays to observe a slight saturation of linearity.

  18. Effects of vacuum exposure on stress and spectral shift of high reflective coatings

    SciTech Connect (OSTI)

    Stolz, C.J.; Taylor, J.R.; Eickelberg, W.K.; Lindh, J.D.

    1992-06-01

    The Atomic Vapor Laser Isotope Laser Separation (AVLIS) program operates the world`s largest average power dye laser; the dye laser beams are combined, formatted, and transported in vacuum. The optical system is aligned at atmosphere, while the system must meet requirements in vacuum. Therefore, coating performance must be characterized in both atmosphere and vacuum. Changes in stress and spectral shift in ambient and vacuum environments are reported for conventional and dense multilayer dielectric coatings.

  19. Effects of vacuum exposure on stress and spectral shift of high reflective coatings

    SciTech Connect (OSTI)

    Stolz, C.J.; Taylor, J.R.; Eickelberg, W.K.; Lindh, J.D.

    1992-06-01

    The Atomic Vapor Laser Isotope Laser Separation (AVLIS) program operates the world's largest average power dye laser; the dye laser beams are combined, formatted, and transported in vacuum. The optical system is aligned at atmosphere, while the system must meet requirements in vacuum. Therefore, coating performance must be characterized in both atmosphere and vacuum. Changes in stress and spectral shift in ambient and vacuum environments are reported for conventional and dense multilayer dielectric coatings.

  20. Airborne Pollution In urban environments

    E-Print Network [OSTI]

    Broday, David

    Airborne Pollution In urban environments What are the real health effects of urban pollution Air Pollution- relevant Human Exposure in Urban Environments" Funded under the "City of Tomorrow" programme of the European Union: Contract number EVK4-CT-2002-00090 URBAN POLLUTION Airborne pollutants

  1. Optical injection and spectral filtering of high-power UV laser diodes

    E-Print Network [OSTI]

    Schäfer, V M; Tock, C J; Lucas, D M

    2015-01-01

    We demonstrate injection-locking of 120mW laser diodes operating at 397nm. We achieve stable operation with injection powers of ~100uW and a slave laser output power of up to 110mW. We investigate the spectral purity of the slave laser light via photon scattering experiments on a single trapped Ca40 ion. We show that it is possible to achieve a scattering rate indistinguishable from that of monochromatic light by filtering the laser light with a diffraction grating to remove amplified spontaneous emission.

  2. CHEMICAL ABUNDANCES IN FIELD RED GIANTS FROM HIGH-RESOLUTION H-BAND SPECTRA USING THE APOGEE SPECTRAL LINELIST

    SciTech Connect (OSTI)

    Smith, Verne V.; Cunha, Katia [National Optical Astronomy Observatories, Tucson, AZ 85719 (United States)] [National Optical Astronomy Observatories, Tucson, AZ 85719 (United States); Shetrone, Matthew D. [Department of Astronomy and McDonald Observatory, University of Texas, Austin, TX 78712 (United States)] [Department of Astronomy and McDonald Observatory, University of Texas, Austin, TX 78712 (United States); Meszaros, Szabolcs; Allende Prieto, Carlos [Instituto d'Astrofisica de Canarias, E-38205, La Laguna, Tenerife (Spain)] [Instituto d'Astrofisica de Canarias, E-38205, La Laguna, Tenerife (Spain); Bizyaev, Dmitry [Apache Point Observatory, Sunspot, NM 88349 (United States)] [Apache Point Observatory, Sunspot, NM 88349 (United States); Garcia Perez, Ana; Majewski, Steven R. [Department of Astronomy, University of Virginia, Charlottesville, VA 22904 (United States)] [Department of Astronomy, University of Virginia, Charlottesville, VA 22904 (United States); Schiavon, Ricardo [Astrophysics Research Institute, Liverpool John Moores University, Liverpool L3 5UX (United Kingdom)] [Astrophysics Research Institute, Liverpool John Moores University, Liverpool L3 5UX (United Kingdom); Holtzman, Jon [Department of Astronomy, New Mexico State University, Las Cruces, NM 88003 (United States)] [Department of Astronomy, New Mexico State University, Las Cruces, NM 88003 (United States); Johnson, Jennifer A., E-mail: vsmith@noao.edu [Department of Astronomy, Ohio State University, Columbus, OH 43210 (United States)

    2013-03-01

    High-resolution H-band spectra of five bright field K, M, and MS giants, obtained from the archives of the Kitt Peak National Observatory Fourier transform spectrometer, are analyzed to determine chemical abundances of 16 elements. The abundances were derived via spectrum synthesis using the detailed linelist prepared for the Sloan Digital Sky Survey III Apache Point Galactic Evolution Experiment (APOGEE), which is a high-resolution near-infrared spectroscopic survey to derive detailed chemical abundance distributions and precise radial velocities for 100,000 red giants sampling all Galactic stellar populations. The red giant sample studied here was chosen to probe which chemical elements can be derived reliably from the H-band APOGEE spectral region. These red giants consist of two K-giants ({alpha} Boo and {mu} Leo), two M-giants ({beta} And and {delta} Oph), and one thermally pulsing asymptotic giant branch (TP-AGB) star of spectral type MS (HD 199799). Measured chemical abundances include the cosmochemically important isotopes {sup 12}C, {sup 13}C, {sup 14}N, and {sup 16}O, along with Mg, Al, Si, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, and Cu. The K and M giants exhibit the abundance signature of the first dredge-up of CN-cycle material, while the TP-AGB star shows clear evidence of the addition of {sup 12}C synthesized during {sup 4}He-burning thermal pulses and subsequent third dredge-up. A comparison of the abundances derived here with published values for these stars reveals consistent results to {approx}0.1 dex. The APOGEE spectral region and linelist is thus well suited for probing both Galactic chemical evolution, as well as internal nucleosynthesis and mixing in populations of red giants via high-resolution spectroscopy.

  3. DISCOVERY OF AN EXTRA HARD SPECTRAL COMPONENT IN THE HIGH-ENERGY AFTERGLOW EMISSION OF GRB 130427A

    SciTech Connect (OSTI)

    Tam, Pak-Hin Thomas [Institute of Astronomy and Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Tang Qingwen; Liu Ruoyu; Wang Xiangyu [School of Astronomy and Space Science, Nanjing University, Nanjing 210093 (China); Hou Shujin, E-mail: phtam@phys.nthu.edu.tw, E-mail: xywang@nju.edu.cn [Department of Astronomy and Institute of Theoretical Physics and Astrophysics, Xiamen University, Xiamen, Fujian 361005 (China)

    2013-07-01

    The extended high-energy gamma-ray (>100 MeV) emission which occurs after prompt gamma-ray bursts (GRBs) is usually characterized by a single power-law spectrum, which has been explained as the afterglow synchrotron radiation. The afterglow inverse Compton emission has long been predicted to be able to produce a high-energy component as well, but previous observations have not clearly revealed such a signature, probably due to the small number of >10 GeV photons even for the brightest GRBs known so far. In this Letter, we report on the Fermi Large Area Telescope observations of the >100 MeV emission from the very bright and nearby GRB 130427A. We characterize the time-resolved spectra of the GeV emission from the GRB onset to the afterglow phase. By performing time-resolved spectral fits of GRB 130427A, we found strong evidence of an extra hard spectral component that exists in the extended high-energy emission of this GRB. We argue that this hard component may arise from the afterglow inverse Compton emission.

  4. The Spectral Amplitude of Stellar Convection and its Scaling in the High-Rayleigh-Number Regime

    E-Print Network [OSTI]

    Featherstone, Nicholas A

    2015-01-01

    Convection plays a central role in the dynamics of any stellar interior, and yet its operation remains largely-hidden from direct observation. As a result, much of our understanding concerning stellar convection necessarily derives from theoretical and computational models. The Sun is, however, exceptional in that regard. The wealth of observational data afforded by its proximity provides a unique testbed for comparing convection models against observations. When such comparisons are carried out, surprising inconsistencies between those models and observations become apparent. Both photospheric and helioseismic measurements suggest that convection simulations may overestimate convective flow speeds on large spatial scales. Moreover, many solar convection simulations have difficulty reproducing the observed solar differential rotation due to this apparent overestimation. We present a series of 3-dimensional (3-D) stellar convection simulations designed to examine how the amplitude and spectral distribution of ...

  5. Modeling for Airborne Contamination

    SciTech Connect (OSTI)

    F.R. Faillace; Y. Yuan

    2000-08-31

    The objective of Modeling for Airborne Contamination (referred to from now on as ''this report'') is to provide a documented methodology, along with supporting information, for estimating the release, transport, and assessment of dose to workers from airborne radioactive contaminants within the Monitored Geologic Repository (MGR) subsurface during the pre-closure period. Specifically, this report provides engineers and scientists with methodologies for estimating how concentrations of contaminants might be distributed in the air and on the drift surfaces if released from waste packages inside the repository. This report also provides dose conversion factors for inhalation, air submersion, and ground exposure pathways used to derive doses to potentially exposed subsurface workers. The scope of this report is limited to radiological contaminants (particulate, volatile and gaseous) resulting from waste package leaks (if any) and surface contamination and their transport processes. Neutron activation of air, dust in the air and the rock walls of the drift during the preclosure time is not considered within the scope of this report. Any neutrons causing such activation are not themselves considered to be ''contaminants'' released from the waste package. This report: (1) Documents mathematical models and model parameters for evaluating airborne contaminant transport within the MGR subsurface; and (2) Provides tables of dose conversion factors for inhalation, air submersion, and ground exposure pathways for important radionuclides. The dose conversion factors for air submersion and ground exposure pathways are further limited to drift diameters of 7.62 m and 5.5 m, corresponding to the main and emplacement drifts, respectively. If the final repository design significantly deviates from these drift dimensions, the results in this report may require revision. The dose conversion factors are further derived by using concrete of sufficient thickness to simulate the drift walls. The gamma-ray scattering properties of concrete are sufficiently similar to those of the host rock and proposed insert material; use of concrete will have no significant impact on the conclusions. The information in this report is presented primarily for use in performing pre-closure radiological safety evaluations of radiological contaminants, but it may also be used to develop strategies for contaminant leak detection and monitoring in the MGR. Included in this report are the methods for determining the source terms and release fractions, and mathematical models and model parameters for contaminant transport and distribution within the repository. Various particle behavior mechanisms that affect the transport of contaminant are included. These particle behavior mechanisms include diffusion, settling, resuspension, agglomeration and other deposition mechanisms.

  6. Spin and Spectral Variations of Peculiar High-Mass X-ray Binary 4U 2206+54

    E-Print Network [OSTI]

    Wang, Wei

    2013-01-01

    Spin properties and spectral variations of high mass X-ray binary 4U 2206+54 are studied with long-term hard X-ray monitoring observations by INTEGRAL. A long-period X-ray pulsar of P_spin\\sim 5558 s has been identified in 4U 2206+54. The spin evolution of the neutron star in 4U 2206+54 is detected with the INTEGRAL/IBIS data. From 2005 to 2011, the spin period of the neutron star in 4U 2206+54 varies from \\sim 5558 s to 5588 s. The average spin-down rate in the last 20 years is derived as \\sim 5\\times 10^{-7} s s^{-1}. 4U 2206+54 is a variable source with luminosities of \\sim 10^{35} - 10^{36} erg s^{-1} in the range of 3 -- 100 keV. Its spectrum can be described by an absorbed power-law model with exponential rolloff. The hydrogen column density and photon index show the anti-correlations with hard X-ray luminosity: low column density and small photon index at maximum of luminosity. This spectral variation pattern suggests that 4U 2206+54 would be a highly obscured binary system. Furthermore, the possible c...

  7. Airborne agent concentration analysis

    DOE Patents [OSTI]

    Gelbard, Fred

    2004-02-03

    A method and system for inferring airborne contaminant concentrations in rooms without contaminant sensors, based on data collected by contaminant sensors in other rooms of a building, using known airflow interconnectivity data. The method solves a least squares problem that minimizes the difference between measured and predicted contaminant sensor concentrations with respect to an unknown contaminant release time. Solutions are constrained to providing non-negative initial contaminant concentrations in all rooms. The method can be used to identify a near-optimal distribution of sensors within the building, when then number of available sensors is less than the total number of rooms. This is achieved by having a system-sensor matrix that is non-singular, and by selecting that distribution which yields the lowest condition number of all the distributions considered. The method can predict one or more contaminant initial release points from the collected data.

  8. Airborne Wind Turbine

    SciTech Connect (OSTI)

    2010-09-01

    Broad Funding Opportunity Announcement Project: Makani Power is developing an Airborne Wind Turbine (AWT) that eliminates 90% of the mass of a conventional wind turbine and accesses a stronger, more consistent wind at altitudes of near 1,000 feet. At these altitudes, 85% of the country can offer viable wind resources compared to only 15% accessible with current technology. Additionally, the Makani Power wing can be economically deployed in deep offshore waters, opening up a resource which is 4 times greater than the entire U.S. electrical generation capacity. Makani Power has demonstrated the core technology, including autonomous launch, land, and power generation with an 8 meter wingspan, 20 kW prototype. At commercial scale, Makani Power aims to develop a 600 kW, 28 meter wingspan product capable of delivering energy at an unsubsidized cost competitive with coal, the current benchmark for low-cost power.

  9. A Very High Spectral Resolution Study of Ground-State OH Masers in W3(OH)

    E-Print Network [OSTI]

    Vincent L. Fish; Walter F. Brisken; Loránt O. Sjouwerman

    2006-04-25

    We present VLBA observations of the ground-state hydroxyl masers in W3(OH) at 0.02 km s-1 spectral resolution. Over 250 masers are detected, including 56 Zeeman pairs. Lineshapes are predominantly Gaussian or combinations of several Gaussians, with normalized deviations typically of the same magnitude as in masers in other species. Typical FWHM maser linewidths are 0.15 to 0.38 km s-1 and are larger in the 1665 MHz transition than in the other three ground-state transitions. The satellite-line 1612 and 1720 MHz masers show no evidence of sigma^+/-2,3 components. The spatial positions of most masers are seen to vary across the line profile, with many spots showing clear, organized positional gradients. Equivalent line-of-sight velocity gradients in the plane of the sky typically range from 0.01 to 1 km s-1 AU-1 (i.e., positional gradients of 1 to 100 AU (km s-1)-1). Small velocity gradients in the 1667 MHz transition support theoretical predictions that 1667 MHz masers appear in regions with small velocity shifts along the amplification length. Deconvolved maser spot sizes appear to be larger in the line wings but do not support a spherical maser geometry.

  10. The far-infrared--submm spectral energy distribution of high-redshift quasars

    E-Print Network [OSTI]

    Robert S. Priddey; Richard G. McMahon

    2001-04-10

    We combine submm photometric data of z>4 quasars, to obtain a mean far-infrared (FIR) (rest-frame) spectral energy distribution (SED) of thermal emission from dust, parameterised by a single temperature (T) and power-law emissivity index (beta). Best-fit values are T=41+/-5K, beta=1.95+/-0.3. The redshift spread of this set of quasars is exploited to allow us to sample the SED at a greater number of rest wavelengths than is possible for a single object. This parameterisation is of use to any study that extrapolates from a flux at a single submm wavelength, for example to infer dust masses and FIR luminosities. We then interpret the submm component as arising from dust heated by star-formation in the quasar's host galaxy, and investigate a simple scheme of AGN--host coevolution, in which the timescale for formation of the host galaxy is c.0.5-1.0Gyr, with star formation proceeding at a constant rate c.1000Msol/yr. The luminous quasar phase occurs towards the end of the star-forming period, just before the galaxy's reservoir of cold gas is depleted. Given the youth of the Universe at z=4 (1.6Gyr), the coexistence of a massive black hole and a luminous starburst can be a powerful constraint on models of quasar host-galaxy formation.

  11. Airborne Volcanic Ash--A Global Threat to Aviation U.S. Department of the Interior

    E-Print Network [OSTI]

    Airborne Volcanic Ash--A Global Threat to Aviation U.S. Department of the Interior U.S. Geological on the aviation industry. Airborne volcanic ash can be a serious hazard to aviation even hundreds of miles from an eruption. Encounters with high-concentration ash clouds can diminish visibility, damage flight control

  12. Massively-parallel Spectral Element Algorithm Development for High Speed Flows 

    E-Print Network [OSTI]

    Camp, Joshua Lane

    2013-10-07

    struggle (an example of this being combustor flows). A relatively recent compromise between the stringent requirement of DNS and the reduced accuracy of RANS is large-eddy simulation, or LES. Although many variants exist, a common approach among LES models... million processes with a parallel efficiency of over 60% [10]. Using NEK5000, our group has simulated several gas turbine components using LES and DNS, including a high pressure turbine blade [14], low pressure turbine blade [15], and cold flow combustor...

  13. Signal processing for airborne bistatic radar 

    E-Print Network [OSTI]

    Ong, Kian P

    The major problem encountered by an airborne bistatic radar is the suppression of bistatic clutter. Unlike clutter echoes for a sidelooking airborne monostatic radar, bistatic clutter echoes are range dependent. Using ...

  14. High resolution FT-ICR mass spectral analysis of bio-oil and residual water soluble organics produced by hydrothermal liquefaction of the marine microalga Nannochloropsis salina

    SciTech Connect (OSTI)

    Sudasinghe, Nilusha; Dungan, Barry; Lammers, Peter; Albrecht, Karl O.; Elliott, Douglas C.; Hallen, Richard T.; Schaub, Tanner

    2014-03-01

    We report a detailed compositional characterization of a bio-crude oil and aqueous by-product from hydrothermal liquefaction of Nannochloropsis salina by direct infusion Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR MS) in both positive- and negative-ionization modes. The FT-ICR MS instrumentation approach facilitates direct assignment of elemental composition to >7000 resolved mass spectral peaks and three-dimensional mass spectral images for individual heteroatom classes highlight compositional diversity of the two samples and provide a baseline description of these materials. Aromatic nitrogen compounds and free fatty acids are predominant species observed in both the bio-oil and aqueous fraction. Residual organic compounds present in the aqueous fraction show distributions that are slightly lower in both molecular ring and/or double bond value and carbon number relative to those found in the bio-oil, albeit with a high degree of commonality between the two compositions.

  15. Airborne Data Processing and Analysis Software Package

    E-Print Network [OSTI]

    Delene, David J.

    Airborne Data Processing and Analysis Software Package David J. Delene1 1 Department of Atmospheric-9006 Correspondance Email: delene@aero.und.edu Software Article submitted to Earth Science Informatics on 28 December Measurement, Open Source Scientific Software, Airborne Measurements, Research Aircraft 1 #12;Abstract

  16. Measurement of high-energy (10–60 keV) x-ray spectral line widths with eV accuracy

    SciTech Connect (OSTI)

    Seely, J. F., E-mail: seelyjf@gmail.com; Feldman, U. [Artep Inc., 2922 Excelsior Springs Court, Ellicott City, Maryland 21042 (United States); Glover, J. L.; Hudson, L. T.; Ralchenko, Y.; Henins, Albert [National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States); Pereira, N. [Ecopulse Inc., P. O. Box 528, Springfield, Virginia 22152 (United States); Di Stefano, C. A.; Kuranz, C. C.; Drake, R. P. [University of Michigan, Ann Arbor, Michigan 48109 (United States); Chen, Hui; Williams, G. J.; Park, J. [Lawrence Livermore National Laboratory, Livermore, California 94551 (United States)

    2014-11-15

    A high resolution crystal spectrometer utilizing a crystal in transmission geometry has been developed and experimentally optimized to measure the widths of emission lines in the 10–60 keV energy range with eV accuracy. The spectrometer achieves high spectral resolution by utilizing crystal planes with small lattice spacings (down to 2d = 0.099 nm), a large crystal bending radius and Rowland circle diameter (965 mm), and an image plate detector with high spatial resolution (60 ?m in the case of the Fuji TR image plate). High resolution W L-shell and K-shell laboratory test spectra in the 10–60 keV range and Ho K-shell spectra near 47 keV recorded at the LLNL Titan laser facility are presented. The Ho K-shell spectra are the highest resolution hard x-ray spectra recorded from a solid target irradiated by a high-intensity laser.

  17. MSIV leakage airborne iodine transport

    SciTech Connect (OSTI)

    Cline, J.E. (Cline Associates Inc., Rockville, MD (United States))

    1993-01-01

    Gaseous iodine deposits on surfaces exposed to vapors. Basic chemical and physical principles predict this behavior, and several laboratory and in-plant measurements demonstrate the characteristic. An empirical model was developed that describes the deposition, resuspension, and transformation of airborne radioiodine molecular species as a stream containing these forms moves along its pathway. The model uses a data base of measured values of deposition and resuspension rates in its application and describes the conversion of the more reactive inorganic iodine species I[sub 2] to the less reactive organic species CH[sub 3]I as the iodine deposits and resuspends along the path. It also considers radioactive decay and chemical surface bonding during residence on surfaces. For the 8-day [sup 131]I, decay during the airborne portion of the transport is negligible. Verification of the model included measurement tests of long gaseous-activity sampling lines of different diameters, operated at different flow rates and stream temperatures. The model was applied to the streams at a boiling water reactor nuclear power plant to describe the transport through leaking main steam isolation valves (MSIVs), following a loss-of-coolant accident.

  18. Geophex Airborne Unmanned Survey System

    SciTech Connect (OSTI)

    Won, I.L.; Keiswetter, D.

    1995-12-31

    Ground-based surveys place personnel at risk due to the proximity of buried unexploded ordnance (UXO) items or by exposure to radioactive materials and hazardous chemicals. The purpose of this effort is to design, construct, and evaluate a portable, remotely-piloted, airborne, geophysical survey system. This non-intrusive system will provide stand-off capability to conduct surveys and detect buried objects, structures, and conditions of interest at hazardous locations. During a survey, the operators remain remote from, but within visual distance of, the site. The sensor system never contacts the Earth, but can be positioned near the ground so that weak geophysical anomalies can be detected. The Geophex Airborne Unmanned Survey System (GAUSS) is designed to detect and locate small-scale anomalies at hazardous sites using magnetic and electromagnetic survey techniques. The system consists of a remotely-piloted, radio-controlled, model helicopter (RCH) with flight computer, light-weight geophysical sensors, an electronic positioning system, a data telemetry system, and a computer base-station. The report describes GAUSS and its test results.

  19. Parametric Explosion Spectral Model

    SciTech Connect (OSTI)

    Ford, S R; Walter, W R

    2012-01-19

    Small underground nuclear explosions need to be confidently detected, identified, and characterized in regions of the world where they have never before occurred. We develop a parametric model of the nuclear explosion seismic source spectrum derived from regional phases that is compatible with earthquake-based geometrical spreading and attenuation. Earthquake spectra are fit with a generalized version of the Brune spectrum, which is a three-parameter model that describes the long-period level, corner-frequency, and spectral slope at high-frequencies. Explosion spectra can be fit with similar spectral models whose parameters are then correlated with near-source geology and containment conditions. We observe a correlation of high gas-porosity (low-strength) with increased spectral slope. The relationship between the parametric equations and the geologic and containment conditions will assist in our physical understanding of the nuclear explosion source.

  20. AIRBORNE, OPTICAL REMOTE SENSNG OF METHANE AND ETHANE FOR NATURAL GAS PIPELINE LEAK DETECTION

    SciTech Connect (OSTI)

    Jerry Myers

    2005-04-15

    Ophir Corporation was awarded a contract by the U. S. Department of Energy, National Energy Technology Laboratory under the Project Title ''Airborne, Optical Remote Sensing of Methane and Ethane for Natural Gas Pipeline Leak Detection'' on October 14, 2002. The scope of the work involved designing and developing an airborne, optical remote sensor capable of sensing methane and, if possible, ethane for the detection of natural gas pipeline leaks. Flight testing using a custom dual wavelength, high power fiber amplifier was initiated in February 2005. Ophir successfully demonstrated the airborne system, showing that it was capable of discerning small amounts of methane from a simulated pipeline leak. Leak rates as low as 150 standard cubic feet per hour (scf/h) were detected by the airborne sensor.

  1. Chemistry of airborne particles from metallurgical processing

    E-Print Network [OSTI]

    Jenkins, Neil Travis, 1973-

    2003-01-01

    Airborne particles fall into one of three size ranges. The nucleation range consists of nanoparticles created from vapor atom collisions. The decisive parameter for particle size and composition is the supercooling of the ...

  2. Principles for Sampling Airborne Radioactivity from Stacks

    SciTech Connect (OSTI)

    Glissmeyer, John A.

    2010-10-18

    This book chapter describes the special processes involved in sampling the airborne effluents from nuclear faciities. The title of the book is Radioactive Air Sampling Methods. The abstract for this chapter was cleared as PNNL-SA-45941.

  3. Airborne measured analytic signal for UXO detection

    SciTech Connect (OSTI)

    Gamey, T.J.; Holladay, J.S. [Aerodat Inc., Mississauga, Ontario (Canada); Mahler, R. [Industrieanlagen Betriebsgesellschaft, Deutschland (Australia)

    1997-10-01

    The Altmark Tank Training Range north of Haldensleben, Germany has been in operation since WWI. Weapons training and testing has included cavalry, cannon, small arms, rail guns, and tank battalions. Current plans are to convert the area to a fully digital combat training facility. Instead of using blank or dummy ordnance, hits will be registered with lasers and computers. Before this can happen, the 25,000 ha must be cleared of old debris. In support of this cleanup operation, Aerodat Inc., in conjunction with IABG of Germany, demonstrated a new high resolution magnetic survey technique involving the measurement of 3-component magnetic gradient data. The survey was conducted in May 1996, and covered 500 ha in two blocks. The nominal line spacing was 10 m, and the average sensor altitude was 7 m. The geologic column consisted of sands over a sedimentary basin. Topographic relief was generally flat with approximately 3 m rolling dunes and occasional man-made features such as fox holes, bunkers, tank traps and reviewing stands. Trees were sparse and short (2-3 metres) due to frequent burn off and tank activity. As such, this site was nearly ideal for low altitude airborne surveying.

  4. High-resolution grazing-incidence grating spectrometer for temperature measurements of low-Z ions emitting in the 100–300 Å spectral band

    SciTech Connect (OSTI)

    Widmann, K., E-mail: widmann1@llnl.gov; Beiersdorfer, P.; Magee, E. W. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Boyle, D. P.; Kaita, R.; Majeski, R. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)

    2014-11-15

    We have constructed a high-resolution grazing-incidence spectrometer designed for measuring the ion temperature of low-Z elements, such as Li{sup +} or Li{sup 2+}, which radiate near 199 Å and 135 Å, respectively. Based on measurements at the Livermore Electron Beam Ion Trap we have shown that the instrumental resolution is better than 48 mÅ at the 200 Å setting and better than 40 mÅ for the 135-Å range. Such a high spectral resolution corresponds to an instrumental limit for line-width based temperature measurements of about 45 eV for the 199 Å Li{sup +} and 65 eV for the 135 Å Li{sup 2+} lines. Recently obtained survey spectra from the Lithium Tokamak Experiment at the Princeton Plasma Physics Laboratory show the presence of these lithium emission lines and the expected core ion temperature of approximately 70 eV is sufficiently high to demonstrate the feasibility of utilizing our high-resolution spectrometer as an ion-temperature diagnostic.

  5. Effect of sampling height on the concentration of airborne fungal spores

    E-Print Network [OSTI]

    Levetin, Estelle

    and possible sources of air pollution.8 In addition, it is high enough to avoid vandalism and bothering aeroallergens. Airborne fungal spores are commonly collected from the outdoor air at the rooftop level of high respiration level (1.5 m above the ground) and at roof level (12 m height). Methods: Air samples were

  6. 572 OPTICS LETTERS / Vol. 25, No. 8 / April 15, 2000 Subhertz spectral fluctuations from high-density

    E-Print Network [OSTI]

    Snoke, David

    low-frequency fluctuations at high excitation density. These were also interpreted as critical of the indirect excitons shifts strongly with electric field because of the quantum-confined Stark effect to record movies of the luminescence spec- trum in real time. In this way we observed a dra- matic onset

  7. Micro-Electron Spin Resonance for Airborne Soot Measurement

    Broader source: Energy.gov [DOE]

    A real-time method for airborne soot concentration measurement using a miniaturized electron spin resonance sensor is presented.

  8. Sandia Multispectral Airborne Lidar for UAV Deployment

    SciTech Connect (OSTI)

    Daniels, J.W.; Hargis,Jr. P.J.; Henson, T.D.; Jordan, J.D.; Lang, A.R.; Schmitt, R.L.

    1998-10-23

    Sandia National Laboratories has initiated the development of an airborne system for W laser remote sensing measurements. System applications include the detection of effluents associated with the proliferation of weapons of mass destruction and the detection of biological weapon aerosols. This paper discusses the status of the conceptual design development and plans for both the airborne payload (pointing and tracking, laser transmitter, and telescope receiver) and the Altus unmanned aerospace vehicle platform. Hardware design constraints necessary to maintain system weight, power, and volume limitations of the flight platform are identified.

  9. Spectral Graph Theory

    E-Print Network [OSTI]

    *D. J. Kelleher

    2011-09-30

    Spectral Graph Theory. *D. J. Kelleher2. 2Department of Mathematics. University of Connecticut. UConn— SIGMA Seminar — Fall 2011. D. J. Kelleher. Spectral ...

  10. High Spectral and Spatial Resolution Observations of the PDR Emission in the NGC2023 Reflection Nebula with SOFIA and APEX

    E-Print Network [OSTI]

    Sandell, G; Guesten, R; Requena-Torres, M A; Riquelme, D; Okada, Y

    2015-01-01

    We have mapped the NGC 2023 reflection nebula in [CII] and CO(11--10) with the heterodyne receiver GREAT on SOFIA and obtained slightly smaller maps in 13CO(3--2), CO(3--2), CO(4--3), CO(6--5), and CO(7--6) with APEX in Chile. We use these data to probe the morphology, kinematics, and physical conditions of the C II region, which is ionized by FUV radiation from the B2 star HD37903. The [CII] emission traces an ellipsoidal shell-like region at a position angle of ~ -50 deg, and is surrounded by a hot molecular shell. In the southeast, where the C II region expands into a dense, clumpy molecular cloud ridge, we see narrow and strong line emission from high-J CO lines, which comes from a thin, hot molecular shell surrounding the [CII] emission. The [CII] lines are broader and show photo evaporating gas flowing into the C II region. Based on the strength of the [13CII] F=2--1 line, the [CII] line appears to be somewhat optically thick over most of the nebula with an optical depth of a few. We model the physical ...

  11. AMBER/VLTI high spectral resolution observations of the Br$\\gamma$ emitting region in HD 98922. A compact disc wind launched from the inner disc region

    E-Print Network [OSTI]

    Garatti, A Caratti o; Lopez, R Garcia; Kraus, S; Schertl, D; Grinin, V P; Weigelt, G; Hofmann, K -H; Massi, F; Lagarde, S; Vannier, M; Malbet, F

    2015-01-01

    We analyse the main physical parameters and the circumstellar environment of the young Herbig Be star HD 98922. We present AMBER/VLTI high spectral resolution (R =12000) interferometric observations across the Br$\\gamma$ line, accompanied by UVES high-resolution spectroscopy and SINFONI-AO assisted near-infrared integral field spectroscopic data. To interpret our observations, we develop a magneto-centrifugally driven disc-wind model. Our analysis of the UVES spectrum shows that HD 98922 is a young (~5x10^5 yr) Herbig Be star (SpT=B9V), located at a distance of 440(+60-50) pc, with a mass accretion rate of ~9+/-3x10^(-7) M_sun yr^(-1). SINFONI K-band AO-assisted imaging shows a spatially resolved circumstellar disc-like region (~140 AU in diameter) with asymmetric brightness distribution. Our AMBER/VLTI UT observations indicate that the Br$\\gamma$ emitting region (radius ~0.31+/-0.04 AU) is smaller than the continuum emitting region (inner dust radius ~0.7+/-0.2 AU), showing significant non-zero V-shaped diff...

  12. Preliminary calculations on direct heating of a containment atmosphere by airborne core debris

    SciTech Connect (OSTI)

    Pilch, M.; Tarbell, W.W.

    1986-07-01

    Direct heating of the containment atmosphere by airborne core debris may be a significant source of containment pressurization in those accident sequences where the primary system is still at high pressure when the RPV fails. Vigorous blowdown of the primary system may result in nearly complete relocation of core debris out of the reactor cavity and possibly into the containment atmosphere where the liberation of thermal and chemical energy can directly heat the atmosphere. Rate independent and rate dependent models are developed and exercised parametrically to quantify the possible magnitude and rate of containment pressurization from direct heating. The possible mitigative effects of airborne water and subcompartment heating are also investigated.

  13. Indoor airborne bacterial communities are influenced by ventilation, occupancy, and outdoor air source

    E-Print Network [OSTI]

    Bohannan, Brendan

    , is an energy-efficient way to simultaneously cool building mass and avoid overnight and weekend microbial an intensive temporal study of indoor airborne bacterial communities in a high-traffic university building associated with differing ventilation strategies relevant to modern building design. Our results indicate

  14. An Epi-Detected Coherent Anti-Stokes Raman Scattering (E-CARS) Microscope with High Spectral Resolution and High Sensitivity

    E-Print Network [OSTI]

    Xie, Xiaoliang Sunney

    LETTERS An Epi-Detected Coherent Anti-Stokes Raman Scattering (E-CARS) Microscope with High-detected coherent anti-Stokes Raman scattering (E-CARS) microscope that uses two synchronized picosecond pulse (CARS) microscopy provides a unique approach to imaging chemical and biological samples by using

  15. Radiometry High Spectral Resolution Fourier

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMassR&D100 Winners * Impacts on GlobalRachel2 Radiometer Characterization System

  16. AIRBORNE, OPTICAL REMOTE SENSING OF METHANE AND ETHANE FOR NATURAL GAS PIPLINE LEAK DETECTION

    SciTech Connect (OSTI)

    Jerry Myers

    2004-05-12

    Ophir Corporation was awarded a contract by the U. S. Department of Energy, National Energy Technology Laboratory under the Project Title ''Airborne, Optical Remote Sensing of Methane and Ethane for Natural Gas Pipeline Leak Detection'' on October 14, 2002. The third six-month technical report contains a summary of the progress made towards finalizing the design and assembling the airborne, remote methane and ethane sensor. The vendor has been chosen and is on contract to develop the light source with the appropriate linewidth and spectral shape to best utilize the Ophir gas correlation software. Ophir has expanded upon the target reflectance testing begun in the previous performance period by replacing the experimental receiving optics with the proposed airborne large aperture telescope, which is theoretically capable of capturing many times more signal return. The data gathered from these tests has shown the importance of optimizing the fiber optic receiving fiber to the receiving optic and has helped Ophir to optimize the design of the gas cells and narrowband optical filters. Finally, Ophir will discuss remaining project issues that may impact the success of the project.

  17. 1 Airborne SLAMJonghyuk KIM UAV Navigation: Airborne Inertial SLAM

    E-Print Network [OSTI]

    Kim, Jonghyuk "Jon"

    for such vehicles have been formulated in the past, the core sensing device has been an Inertial Measurement Unit (IMU). These units measure acceleration and rotation rates of a platform at high update rates, which and Inertial Measurement Units Inertial Navigation Aided Inertial Navigation Structure Inertial SLAM - EKF

  18. Analyzing Options for Airborne Emergency Wireless Communications

    SciTech Connect (OSTI)

    Michael Schmitt; Juan Deaton; Curt Papke; Shane Cherry

    2008-03-01

    In the event of large-scale natural or manmade catastrophic events, access to reliable and enduring commercial communication systems is critical. Hurricane Katrina provided a recent example of the need to ensure communications during a national emergency. To ensure that communication demands are met during these critical times, Idaho National Laboratory (INL) under the guidance of United States Strategic Command has studied infrastructure issues, concerns, and vulnerabilities associated with an airborne wireless communications capability. Such a capability could provide emergency wireless communications until public/commercial nodes can be systematically restored. This report focuses on the airborne cellular restoration concept; analyzing basic infrastructure requirements; identifying related infrastructure issues, concerns, and vulnerabilities and offers recommended solutions.

  19. MAPPING FELDSPARS WITH AIRBORNE HYPERSPECTRAL SEBASS IMAGERY

    E-Print Network [OSTI]

    OSU DEAN RILEY AERO / SPECTIR MARK VAN DER MEIJDE ITC-UT FREEK VAN DER MEER ITC-UT #12;MINERAL MODES://www.lpi.usra.edu/science/kirkland/Mesa/text.html Data courtesy Dr. Dean Riley, Aero.org APPLICATION TO AIRBORNE HYPERSPECTRAL IMAGE DATA AEROSPACE HECKER ITC-UT JOHN DILLES OSU DEAN RILEY AERO / SPECTIR MARK VAN DER MEIJDE ITC-UT FREEK VAN DER MEER ITC

  20. Airborne Tactical Free-Electron Laser

    SciTech Connect (OSTI)

    Roy Whitney; George Neil

    2007-02-01

    The goal of 100 kilowatts (kW) of directed energy from an airborne tactical platform has proved challenging due to the size and weight of most of the options that have been considered. However, recent advances in Free-Electron Lasers appear to offer a solution along with significant tactical advantages: a nearly unlimited magazine, time structures for periods from milliseconds to hours, radar like functionality, and the choice of the wavelength of light that best meets mission requirements. For an Airborne Tactical Free-Electron Laser (ATFEL) on a platforms such as a Lockheed C-130J-30 and airships, the two most challenging requirements, weight and size, can be met by generating the light at a higher harmonic, aggressively managing magnet weights, managing cryogenic heat loads using recent SRF R&D results, and using FEL super compact design concepts that greatly reduce the number of components. The initial R&D roadmap for achieving an ATFEL is provided in this paper. Performing this R&D is expected to further reduce the weight, size and power requirements for the FELs the Navy is currently developing for shipboard applications, as well as providing performance enhancements for the strategic airborne MW class FELs. The 100 kW ATFEL with its tactical advantages may prove sufficiently attractive for early advancement in the queue of deployed FELs.

  1. The Airborne Metagenome in an Indoor Urban Environment

    E-Print Network [OSTI]

    Tringe, Susannah

    2009-01-01

    independent approaches to microbes harvested from the air ofthat the indoor air microbes are not random transients fromhealth policies. Airborne microbes are often attached to

  2. ccpi-airborne_r2 | netl.doe.gov

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    COMMERCIAL SCALE DEMONSTRATION PROGRAM MUSTANG CLEAN ENERGY, LLC, a subsidiary of PEABODY ENERGY ST. LOUIS, MISSOURI PROJECT FACT SHEET Airborne Process(tm) Commercial Scale...

  3. Effects of particle size and velocity on burial depth of airborne particles in glass fiber filters

    SciTech Connect (OSTI)

    Higby, D.P.

    1984-11-01

    Air sampling for particulate radioactive material involves collecting airborne particles on a filter and then determining the amount of radioactivity collected per unit volume of air drawn through the filter. The amount of radioactivity collected is frequently determined by directly measuring the radiation emitted from the particles collected on the filter. Counting losses caused by the particle becoming buried in the filter matrix may cause concentrations of airborne particulate radioactive materials to be underestimated by as much as 50%. Furthermore, the dose calculation for inhaled radionuclides will also be affected. The present study was designed to evaluate the extent to which particle size and sampling velocity influence burial depth in glass-fiber filters. Aerosols of high-fired /sup 239/PuO/sub 2/ were collected at various sampling velocities on glass-fiber filters. The fraction of alpha counts lost due to burial was determined as the ratio of activity detected by direct alpha count to the quantity determined by photon spectrometry. The results show that burial of airborne particles collected on glass-fiber filters appears to be a weak function of sampling velocity and particle size. Counting losses ranged from 0 to 25%. A correction that assumes losses of 10 to 15% would ensure that the concentration of airborne alpha-emitting radionuclides would not be underestimated when glass-fiber filters are used. 32 references, 21 figures, 11 tables.

  4. A multivariate spatial interpolation of airborne -ray data using the geological constraints

    E-Print Network [OSTI]

    Roma "La Sapienza", Università di

    A multivariate spatial interpolation of airborne -ray data using the geological constraints Enrico: Multivariate analysis Airborne -ray spectrometry Collocated cokriging interpolator Elba Island Natural (Italy) obtained with a multivariate spatial interpolation of airborne -ray data using the constraints

  5. Multidimensional spectral load balancing

    SciTech Connect (OSTI)

    Hendrickson, B.; Leland, R.

    1993-01-01

    We describe an algorithm for the static load balancing of scientific computations that generalizes and improves upon spectral bisection. Through a novel use of multiple eigenvectors, our new spectral algorithm can divide a computation into 4 or 8 pieces at once. These multidimensional spectral partitioning algorithms generate balanced partitions that have lower communication overhead and are less expensive to compute than those produced by spectral bisection. In addition, they automatically work to minimize message contention on a hypercube or mesh architecture. These spectral partitions are further improved by a multidimensional generalization of the Kernighan-Lin graph partitioning algorithm. Results on several computational grids are given and compared with other popular methods.

  6. Airborne Electromagnetic Survey | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop IncIowaWisconsin: Energy ResourcesAir Quality Jump to: navigation,Airborne

  7. Automatic Extraction of Cartographic Information from Airborne Interferometric SAR Data

    E-Print Network [OSTI]

    Mayer, Helmut A.

    Automatic Extraction of Cartographic Information from Airborne Interferometric SAR Data Reinhold cartographic feature extraction by the airborne AeS--1 instrument is presented. We extract regions corresponding to cartographic features for the classes built--up area, forest, water and open area. Water

  8. Airborne Multisensor Pod System (AMPS) data management overview

    SciTech Connect (OSTI)

    Wiberg, J.D.; Blough, D.K.; Daugherty, W.R.; Hucks, J.A.; Gerhardstein, L.H.; Meitzler, W.D.; Melton, R.B.; Shoemaker, S.V.

    1994-09-01

    An overview of the Data Management Plan for the Airborne Multisensor Pod System (AMPS) pro-grain is provided in this document. The Pacific Northwest Laboratory (PNL) has been assigned the responsibility of data management for the program, which includes defining procedures for data management and data quality assessment. Data management is defined as the process of planning, acquiring, organizing, qualifying and disseminating data. The AMPS program was established by the U.S. Department of Energy (DOE), Office of Arms Control and Non-Proliferation (DOE/AN) and is integrated into the overall DOE AN-10.1 technology development program. Sensors used for collecting the data were developed under the on-site inspection, effluence analysis, and standoff sensor program, the AMPS program interacts with other technology programs of DOE/NN-20. This research will be conducted by both government and private industry. AMPS is a research and development program, and it is not intended for operational deployment, although the sensors and techniques developed could be used in follow-on operational systems. For a complete description of the AMPS program, see {open_quotes}Airborne Multisensor Pod System (AMPS) Program Plan{close_quotes}. The primary purpose of the AMPS is to collect high-quality multisensor data to be used in data fusion research to reduce interpretation problems associated with data overload and to derive better information than can be derived from any single sensor. To collect the data for the program, three wing-mounted pods containing instruments with sensors for collecting data will be flight certified on a U.S. Navy RP-3A aircraft. Secondary objectives of the AMPS program are sensor development and technology demonstration. Pod system integrators and instrument developers will be interested in the performance of their deployed sensors and their supporting data acquisition equipment.

  9. Asthmatic responses to airborne acid aerosols

    SciTech Connect (OSTI)

    Ostro, B.D.; Lipsett, M.J.; Wiener, M.B.; Selner, J.C. )

    1991-06-01

    Controlled exposure studies suggest that asthmatics may be more sensitive to the respiratory effects of acidic aerosols than individuals without asthma. This study investigates whether acidic aerosols and other air pollutants are associated with respiratory symptoms in free-living asthmatics. Daily concentrations of hydrogen ion (H+), nitric acid, fine particulates, sulfates and nitrates were obtained during an intensive air monitoring effort in Denver, Colorado, in the winter of 1987-88. A panel of 207 asthmatics recorded respiratory symptoms, frequency of medication use, and related information in daily diaries. We used a multiple regression time-series model to analyze which air pollutants, if any, were associated with health outcomes reported by study participants. Airborne H+ was found to be significantly associated with several indicators of asthma status, including moderate or severe cough and shortness of breath. Cough was also associated with fine particulates, and shortness of breath with sulfates. Incorporating the participants' time spent outside and exercise intensity into the daily measure of exposure strengthened the association between these pollutants and asthmatic symptoms. Nitric acid and nitrates were not significantly associated with any respiratory symptom analyzed. In this population of asthmatics, several outdoor air pollutants, particularly airborne acidity, were associated with daily respiratory symptoms.

  10. Spectral Operators of Matrices

    E-Print Network [OSTI]

    2014-01-10

    Jan 10, 2014 ... a thorough study on a new class of matrix valued functions, coined as spectral operators of ..... not self-adjoint. ...... 9 (1981) 1135–1151.

  11. Use of airborne laser scanning to characterise land degradation processes the Dead Sea as

    E-Print Network [OSTI]

    Marco, Shmuel "Shmulik"

    . Keywords: Airborne laser scanning, Geomorphology, Dead Sea, Land degradation, Channel incision, Sinkholes

  12. CALIOPE and TAISIR airborne experiment platform

    SciTech Connect (OSTI)

    Chocol, C.J.

    1994-07-01

    Between 1950 and 1970, scientific ballooning achieved many new objectives and made a substantial contribution to understanding near-earth and space environments. In 1986, the Lawrence Livermore National Laboratory (LLNL) began development of ballooning technology capable of addressing issues associated with precision tracking of ballistic missiles. In 1993, the Radar Ocean Imaging Project identified the need for a low altitude (1 km) airborne platform for its Radar system. These two technologies and experience base have been merged with the acquisition of government surplus Aerostats by Lawrence Livermore National Laboratory. The CALIOPE and TAISIR Programs can benefit directly from this technology by using the Aerostat as an experiment platform for measurements of the spill facility at NTS.

  13. Human Occupancy as a Source of Indoor Airborne Bacteria

    E-Print Network [OSTI]

    Hospodsky, Denina

    Exposure to specific airborne bacteria indoors is linked to infectious and noninfectious adverse health outcomes. However, the sources and origins of bacteria suspended in indoor air are not well understood. This study ...

  14. Epidemiology of Airborne Virulent Rhodococcus equi at Horse Breeding Farms 

    E-Print Network [OSTI]

    Kuskie, Kyle Ryan

    2012-02-14

    Rhodococcus equi causes severe pneumonia, resulting in disease and sometimes death of foals. Infection is thought to occur by inhalation of dust contaminated with virulent R equi. A recent study of 3 horse breeding farms in Ireland found airborne...

  15. Spectral diagonal ensemble Kalman filters

    E-Print Network [OSTI]

    Kasanický, Ivan; Vejmelka, Martin

    2015-01-01

    A new type of ensemble Kalman filter is developed, which is based on replacing the sample covariance in the analysis step by its diagonal in a spectral basis. It is proved that this technique improves the aproximation of the covariance when the covariance itself is diagonal in the spectral basis, as is the case, e.g., for a second-order stationary random field and the Fourier basis. The method is extended by wavelets to the case when the state variables are random fields, which are not spatially homogeneous. Efficient implementations by the fast Fourier transform (FFT) and discrete wavelet transform (DWT) are presented for several types of observations, including high-dimensional data given on a part of the domain, such as radar and satellite images. Computational experiments confirm that the method performs well on the Lorenz 96 problem and the shallow water equations with very small ensembles and over multiple analysis cycles.

  16. Airborne spread of foot-and-mouth disease - model intercomparison

    SciTech Connect (OSTI)

    Gloster, J; Jones, A; Redington, A; Burgin, L; Sorensen, J H; Turner, R; Dillon, M; Hullinger, P; Simpson, M; Astrup, P; Garner, G; Stewart, P; D'Amours, R; Sellers, R; Paton, D

    2008-09-04

    Foot-and-mouth disease is a highly infectious vesicular disease of cloven-hoofed animals caused by foot-and-mouth disease virus. It spreads by direct contact between animals, by animal products (milk, meat and semen), by mechanical transfer on people or fomites and by the airborne route - with the relative importance of each mechanism depending on the particular outbreak characteristics. Over the years a number of workers have developed or adapted atmospheric dispersion models to assess the risk of foot-and-mouth disease virus spread through the air. Six of these models were compared at a workshop hosted by the Institute for Animal Health/Met Office during 2008. A number of key issues emerged from the workshop and subsequent modelling work: (1) in general all of the models predicted similar directions for 'at risk' livestock with much of the remaining differences strongly related to differences in the meteorological data used; (2) determination of an accurate sequence of events is highly important, especially if the meteorological conditions vary substantially during the virus emission period; and (3) differences in assumptions made about virus release, environmental fate, and subsequent infection can substantially modify the size and location of the downwind risk area. Close relationships have now been established between participants, which in the event of an outbreak of disease could be readily activated to supply advice or modelling support.

  17. Column closure studies of lower tropospheric aerosol and water vapor during ACE-Asia using airborne Sun photometer and airborne in situ

    E-Print Network [OSTI]

    Sun photometer and airborne in situ and ship-based lidar measurements B. Schmid,1 D. A. Hegg,2 J. Wang (closure) between solar beam attenuation by aerosols and water vapor measured by airborne Sun photometry agreement with airborne Sun photometry in the marine boundary layer but is considerably lower in layers

  18. ARM Airborne Continuous carbon dioxide measurements

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Biraud, Sebastien

    2013-03-26

    The heart of the AOS CO2 Airborne Rack Mounted Analyzer System is the AOS Manifold. The AOS Manifold is a nickel coated aluminum analyzer and gas processor designed around two identical nickel-plated gas cells, one for reference gas and one for sample gas. The sample and reference cells are uniquely designed to provide optimal flushing efficiency. These cells are situated between a black-body radiation source and a photo-diode detection system. The AOS manifold also houses flow meters, pressure sensors and control valves. The exhaust from the analyzer flows into a buffer volume which allows for precise pressure control of the analyzer. The final piece of the analyzer is the demodulator board which is used to convert the DC signal generated by the analyzer into an AC response. The resulting output from the demodulator board is an averaged count of CO2 over a specified hertz cycle reported in volts and a corresponding temperature reading. The system computer is responsible for the input of commands and therefore works to control the unit functions such as flow rate, pressure, and valve control.The remainder of the system consists of compressors, reference gases, air drier, electrical cables, and the necessary connecting plumbing to provide a dry sample air stream and reference air streams to the AOS manifold.

  19. ARM Airborne Continuous carbon dioxide measurements

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Biraud, Sebastien

    The heart of the AOS CO2 Airborne Rack Mounted Analyzer System is the AOS Manifold. The AOS Manifold is a nickel coated aluminum analyzer and gas processor designed around two identical nickel-plated gas cells, one for reference gas and one for sample gas. The sample and reference cells are uniquely designed to provide optimal flushing efficiency. These cells are situated between a black-body radiation source and a photo-diode detection system. The AOS manifold also houses flow meters, pressure sensors and control valves. The exhaust from the analyzer flows into a buffer volume which allows for precise pressure control of the analyzer. The final piece of the analyzer is the demodulator board which is used to convert the DC signal generated by the analyzer into an AC response. The resulting output from the demodulator board is an averaged count of CO2 over a specified hertz cycle reported in volts and a corresponding temperature reading. The system computer is responsible for the input of commands and therefore works to control the unit functions such as flow rate, pressure, and valve control.The remainder of the system consists of compressors, reference gases, air drier, electrical cables, and the necessary connecting plumbing to provide a dry sample air stream and reference air streams to the AOS manifold.

  20. High-order accurate simulation of low-Mach laminar flow past two side-by-side cylinders using spectral difference method

    E-Print Network [OSTI]

    Jameson, Antony

    High-order accurate simulation of low-Mach laminar flow past two side-by-side cylinders using applications on simulating laminar flow past two side-by-side cylinders at various spacings. The high-by-side cylinders Investigations of the fluid flow and vortex dynamics about sim- ple configurations of two

  1. SIZE DISTRIBUTION AND RATE OF PRODUCTION OF AIRBORNE PARTICULATE MATTER GENERATED DURING METAL CUTTING

    SciTech Connect (OSTI)

    M.A. Ebadian, Ph.D.; S.K. Dua, Ph.D., C.H.P.; Hillol Guha, Ph.D.

    2001-01-01

    During deactivation and decommissioning activities, thermal cutting tools, such as plasma torch, laser, and gasoline torch, are used to cut metals. These activities generate fumes, smoke and particulates. These airborne species of matter, called aerosols, may be inhaled if suitable respiratory protection is not used. Inhalation of the airborne metallic aerosols has been reported to cause ill health effects, such as acute respiratory syndrome and chromosome damage in lymphocytes. In the nuclear industry, metals may be contaminated with radioactive materials. Cutting these metals, as in size reduction of gloveboxes and tanks, produces high concentrations of airborne transuranic particles. Particles of the respirable size range (size < 10 {micro}m) deposit in various compartments of the respiratory tract, the fraction and the site in the respiratory tract depending on the size of the particles. The dose delivered to the respiratory tract depends on the size distribution of the airborne particulates (aerosols) and their concentration and radioactivity/toxicity. The concentration of airborne particulate matter in an environment is dependent upon the rate of their production and the ventilation rate. Thus, measuring aerosol size distribution and generation rate is important for (1) the assessment of inhalation exposures of workers, (2) the selection of respiratory protection equipment, and (3) the design of appropriate filtration systems. Size distribution of the aerosols generated during cutting of different metals by plasma torch was measured. Cutting rates of different metals, rate of generation of respirable mass, as well as the fraction of the released kerf that become respirable were determined. This report presents results of these studies. Measurements of the particles generated during cutting of metal plates with a plasma arc torch revealed the presence of particles with mass median aerodynamic diameters of particles close to 0.2 {micro}m, arising from condensation of vaporized material and subsequent rapid formation of aggregates. Particles of larger size, resulting from ejection of melted material or fragments from the cutting zone, were also observed. This study presents data regarding the metal cutting rate, particle size distribution, and their generation rate, while using different cutting tools and metals. The study shows that respirable particles constitute only a small fraction of the released kerf.

  2. Aerosol plume transport and transformation in high spectral resolution lidar measurements and WRF-Flexpart simulations during the MILAGRO Field Campaign

    E-Print Network [OSTI]

    de Foy, B.

    The Mexico City Metropolitan Area (MCMA) experiences high loadings of atmospheric aerosols from anthropogenic sources, biomass burning and wind-blown dust. This paper uses a combination of measurements and numerical ...

  3. Airborne observations of methane emissions from rice cultivation in the Sacramento Valley of California

    E-Print Network [OSTI]

    Goldstein, Allen

    Airborne observations of methane emissions from rice cultivation in the Sacramento Valley 2012; accepted 7 October 2012; published 8 December 2012. [1] Airborne measurements of methane (CH4 is not accounted for in the CARB inventory. Citation: Peischl, J., et al. (2012), Airborne observations of methane

  4. Joint spatio-spectral based edge detection for multispectral infrared imagery.

    SciTech Connect (OSTI)

    Krishna, Sanjay; Hayat, Majeed M.; Bender, Steven C.; Sharma, Yagya D.; Jang, Woo-Yong; Paskalva, Biliana S.

    2010-06-01

    Image segmentation is one of the most important and difficult tasks in digital image processing. It represents a key stage of automated image analysis and interpretation. Segmentation algorithms for gray-scale images utilize basic properties of intensity values such as discontinuity and similarity. However, it is possible to enhance edge-detection capability by means of using spectral information provided by multispectral (MS) or hyperspectral (HS) imagery. In this paper we consider image segmentation algorithms for multispectral images with particular emphasis on detection of multi-color or multispectral edges. More specifically, we report on an algorithm for joint spatio-spectral (JSS) edge detection. By joint we mean simultaneous utilization of spatial and spectral characteristics of a given MS or HS image. The JSS-based edge-detection approach, termed Spectral Ratio Contrast (SRC) edge-detection algorithm, utilizes the novel concept of matching edge signatures. The edge signature represents a combination of spectral ratios calculated using bands that enhance the spectral contrast between the two materials. In conjunction with a spatial mask, the edge signature give rise to a multispectral operator that can be viewed as a three-dimensional extension of the mask. In the extended mask, the third (spectral) dimension of each hyper-pixel can be chosen independently. The SRC is verified using MS and HS imagery from a quantum-dot in a well infrared (IR) focal plane array, and the Airborne Hyperspectral Imager.

  5. Airborne flux measurements of Biogenic Isoprene over California

    SciTech Connect (OSTI)

    Misztal, P.; Karl, Thomas G.; Weber, Robin; Jonsson, H. H.; Guenther, Alex B.; Goldstein, Allen H.

    2014-10-10

    Biogenic Volatile Organic Compound (BVOC) fluxes were measured onboard the CIRPAS Twin Otter aircraft as part of the California Airborne BVOC Emission Research in Natural Ecosystem Transects (CABERNET) campaign during June 2011. The airborne virtual disjunct eddy covariance (AvDEC) approach used measurements from a PTR-MS and a wind radome probe to directly determine fluxes of isoprene, MVK+MAC, methanol, monoterpenes, and MBO over ~10,000-km of flight paths focusing on areas of California predicted to have the largest emissions of isoprene. The Fast Fourier Transform (FFT) approach was used to calculate fluxes over long transects of more than 15 km, most commonly between 50 and 150 km. The Continuous Wavelet Transformation (CWT) approach was used over the same transects to also calculate "instantaneous" fluxes with localization of both frequency and time independent of non-stationarities. Vertical flux divergence of isoprene is expected due to its relatively short lifetime and was measured directly using "racetrack" profiles at multiple altitudes. It was found to be linear and in the range 5% to 30% depending on the ratio of aircraft altitude to PBL height (z/zi). Fluxes were generally measured by flying consistently 1 at 400 m ±50 m (a.g.l.) altitude, and extrapolated to the surface according to the determined flux divergence. The wavelet-derived surface fluxes of isoprene averaged to 2 km spatial resolution showed good correspondence to Basal Emission Factor (BEF) landcover datasets used to drive biogenic VOC (BVOC) emission models. The surface flux of isoprene was close to zero over Central Valley crops and desert shrublands, but was very high (up to 15 mg m-2 h-1) above oak woodlands, with clear dependence of emissions on temperature and oak density. Isoprene concentrations of up to 8 ppb were observed at aircraft height on the hottest days and over the dominant source regions. While isoprene emissions from agricultural crop regions, shrublands, and coniferous forests were extremely low, high concentrations of methanol and monoterpenes were found above some of these regions. These observations demonstrate the ability to measure fluxes from specific sources by eddy covariance from an aircraft, and suggest the utility of measurements using fast response chemical sensors to constrain emission inventories and map out source distributions for a much broader array of trace gases than was observed in this study. This paper reports the first regional direct eddy covariance fluxes of isoprene. The emissions of VOCs measured from aircraft with 2 km spatial resolution can quantify the distribution of major sources providing the observations required for testing statewide emission inventories of these important trace gases. These measurements will be used in a future study to assess BVOC emission models and their driving variable datasets.

  6. Spectral tailoring device

    DOE Patents [OSTI]

    Brager, H.R.; Schenter, R.E.; Carter, L.L.; Karnesky, R.A.

    1987-08-05

    A spectral tailoring device for altering the neutron energy spectra and flux of neutrons in a fast reactor thereby selectively to enhance or inhibit the transmutation rate of a target metrical to form a product isotope. Neutron moderators, neutron filters, neutron absorbers and neutron reflectors may be used as spectral tailoring devices. Depending on the intended use for the device, a member from each of these four classes of materials could be used singularly, or in combination, to provide a preferred neutron energy spectra and flux of the neutrons in the region of the target material. In one embodiment of the invention, an assembly is provided for enhancing the production of isotopes, such as cobalt 60 and gadolinium 153. In another embodiment of the invention, a spectral tailoring device is disposed adjacent a target material which comprises long lived or volatile fission products and the device is used to shift the neutron energy spectra and flux of neutrons in the region of the fission products to preferentially transmute them to produce a less volatile fission product inventory. 6 figs.

  7. Spectral signatures of penumbral transients

    SciTech Connect (OSTI)

    Reardon, K. [INAF-Osservatorio Astrofisico di Arcetri, I-50125 Firenze (Italy); Tritschler, A. [National Solar Observatory/Sacramento Peak, P.O. Box 62, Sunspot, NM 88349 (United States); Katsukawa, Y. [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan)

    2013-12-20

    In this work we investigate the properties of penumbral transients observed in the upper photospheric and chromospheric region above a sunspot penumbra using two-dimensional spectroscopic observations of the Ca II 854.21 nm line with a 5 s cadence. In our 30 minutes of observations, we identify several penumbral-micro jets (PMJs) with cotemporal observations from Dunn Solar Telescope/IBIS and Hinode/SOT. We find that the line profiles of these PMJ events show emission in the two wings of the line (±0.05 nm), but little modification of the line core. These are reminiscent of the line profiles of Ellerman bombs observed in plage and network regions. Furthermore, we find evidence that some PMJ events have a precursor phase starting 1 minute prior to the main brightening that might indicate initial heating of the plasma prior to an acoustic or bow shock event. With the IBIS data, we also find several other types of transient brightenings with timescales of less than 1 minute that are not clearly seen in the Hinode/SOT data. The spectral profiles and other characteristics of these events are significantly different from those of PMJs. The different appearances of all these transients are an indicator of the general complexity of the chromospheric magnetic field and underscore the highly dynamic behavior above sunspots. It also highlights the care that is needed in interpreting broadband filter images of chromospheric lines, which may conceal very different spectral profiles, and the underlying physical mechanisms at work.

  8. Steps towards Quality Improvement of Airborne Laser Scanner Data

    E-Print Network [OSTI]

    Vosselman, George

    , and forestry management. However, to guarantee this level of data quality the measurements must be as closeSteps towards Quality Improvement of Airborne Laser Scanner Data A Behan1 , H-G Maas2 and G for the acquisition of 2.5D data, mainly for use in topographic and mapping operations. In recent years, however

  9. Automatic Construction of Building Footprints from Airborne LIDAR Data

    E-Print Network [OSTI]

    Chen, Shu-Ching

    1 Automatic Construction of Building Footprints from Airborne LIDAR Data Keqi Zhang, Jianhua Yan. INTRODUCTION BUILDING footprints are one of the fundamental GIS data components that can be used to estimate, and estimation of building base elevation for flood insurance [2]. In addition, footprint data in combination

  10. Airborne lidar detection and characterization of internal waves in a

    E-Print Network [OSTI]

    Shaw, Joseph A.

    on the strength of the wind. This tends to create a layer of less dense water on top of the more dense water below of water with lower density at the surface. This layer is typically mixed with the water below. The airborne lidar detected a thin plankton layer at the bottom of the upper layer of the water

  11. Quality Assurance Program Plan for radionuclide airborne emissions monitoring

    SciTech Connect (OSTI)

    Vance, L.M.

    1993-07-01

    This Quality Assurance Program Plan (QAPP) describes the quality assurance requirements and responsibilities for radioactive airborne emissions measurements activities from regulated stacks are controlled at the Hanford Site. Detailed monitoring requirements apply to stacks exceeding 1% of the standard of 10 mrem annual effective dose equivalent to the maximally exposed individual from operations of the Hanford Site.

  12. EPLA: Energy-balancing Packets Scheduling for Airborne Relaying Networks

    E-Print Network [OSTI]

    New South Wales, University of

    of unmanned aerial vehicles (UAVs). We propose an energy-efficient relaying scheme which is able to overcomeEPLA: Energy-balancing Packets Scheduling for Airborne Relaying Networks Kai Li1 Wei Ni2 Xin Wang3 then schedules UAVs' forwarding with guaranteed success rates and balanced energy consumption. Such scheduling

  13. Evaluation of Mali, West Africa Airborne Measurements to Access the

    E-Print Network [OSTI]

    Delene, David J.

    Evaluation of Mali, West Africa Airborne Measurements to Access the Potential of Enhancing if cloud seeding in Mali could be beneficial.c ·Identify optimal seeding method for enhancing precipitation in the Mali region based on conceptual models. #12;Measurement Importance · The potential to enhancing

  14. Three Years of Airborne Measurements in Mali, West Africa

    E-Print Network [OSTI]

    Delene, David J.

    Three Years of Airborne Measurements in Mali, West Africa David Delene Department of Atmospheric of adapting operational programs from other locations to the Mali region. · Advance local scientific knowledge Measurement Objectives · Determine the variability of aerosol and cloud properties in Mali and how

  15. Evaluation of Mali, West Africa Airborne Measurements to Access the

    E-Print Network [OSTI]

    Delene, David J.

    Evaluation of Mali, West Africa Airborne Measurements to Access the Potential of Enhancing Determine if cloud seeding in Mali could be beneficial.b Help determine what is the optimal seeding method for enhancing precipitation in the Mali region. #12;Measurement Importance The potential to enhancing

  16. Measurement of airborne fission products in Chapel Hill, NC, USA from the Fukushima Dai-ichi reactor accident

    E-Print Network [OSTI]

    S. MacMullin; G. K. Giovanetti; M. P. Green; R. Henning; R. Holmes; K. Vorren; J. F. Wilkerson

    2012-10-03

    We present measurements of airborne fission products in Chapel Hill, NC, USA, from 62 days following the March 11, 2011, accident at the Fukushima Dai-ichi nuclear power plant. Airborne particle samples were collected daily in air filters and radio-assayed with two high-purity germanium (HPGe) detectors. The fission products I-131 and Cs-137 were measured with maximum activities of 4.2 +/- 0.6 mBq/m^3 and 0.42 +/- 0.07 mBq/m^3 respectively. Additional activity from I-131, I-132, Cs-134, Cs-136, Cs-137 and Te-132 were measured in the same air filters using a low-background HPGe detector at the Kimballton Underground Research Facility (KURF).

  17. Spectral utilization in thermophotovoltaic devices

    SciTech Connect (OSTI)

    Clevenger, M.B.; Murray, C.S.

    1997-12-31

    Multilayer assemblies of epitaxially-grown, III-V semiconductor materials are being investigated for use in thermophotovoltaic (TPV) energy conversion applications. It has been observed that thick, highly-doped semiconductor layers within cell architectures dominate the parasitic free-carrier absorption (FCA) of devices at wavelengths above the bandgap of the semiconductor material. In this work, the wavelength-dependent, free-carrier absorption of p- and n-type InGaAs layers grown epitaxially onto semi-insulating (SI) InP substrates has been measured and related to the total absorption of long-wavelength photons in thermophotovoltaic devices. The optical responses of the TPV cells are then used in the calculation of spectral utilization factors and device efficiencies.

  18. Motivation Two spectral preconditioners Recombination issue Using Spectral Information to Precondition

    E-Print Network [OSTI]

    1 Motivation Two spectral preconditioners Recombination issue Using Spectral Information #12;2 Motivation Two spectral preconditioners Recombination issue #12;3 Motivation Two spectral preconditioners Recombination issue Outline 1 Motivation 2 Two spectral preconditioners 3 Recombination issue #12

  19. Spatio-spectral image analysis using classical and neural algorithms

    SciTech Connect (OSTI)

    Roberts, S.; Gisler, G.R.; Theiler, J.

    1996-12-31

    Remote imaging at high spatial resolution has a number of environmental, industrial, and military applications. Analysis of high-resolution multi-spectral images usually involves either spectral analysis of single pixels in a multi- or hyper-spectral image or spatial analysis of multi-pixels in a panchromatic or monochromatic image. Although insufficient for some pattern recognition applications individually, the combination of spatial and spectral analytical techniques may allow the identification of more complex signatures that might not otherwise be manifested in the individual spatial or spectral domains. We report on some preliminary investigation of unsupervised classification methodologies (using both ``classical`` and ``neural`` algorithms) to identify potentially revealing features in these images. We apply dimension-reduction preprocessing to the images, duster, and compare the clusterings obtained by different algorithms. Our classification results are analyzed both visually and with a suite of objective, quantitative measures.

  20. Initial Results from an Automated High Spectral

    E-Print Network [OSTI]

    Eloranta, Edwin W.

    is provided to display system housekeeping data as well. We are also preparing web routines to process data same optics for maximum stability of transmit and receive optical axis. - Passive TR switch

  1. High Performance Nanostructured Spectrally Selective Coating

    Broader source: Energy.gov [DOE]

    This presentation was delivered at the SunShot Concentrating Solar Power (CSP) Program Review 2013, held April 23–25, 2013 near Phoenix, Arizona.

  2. Method of multivariate spectral analysis

    DOE Patents [OSTI]

    Keenan, Michael R.; Kotula, Paul G.

    2004-01-06

    A method of determining the properties of a sample from measured spectral data collected from the sample by performing a multivariate spectral analysis. The method can include: generating a two-dimensional matrix A containing measured spectral data; providing a weighted spectral data matrix D by performing a weighting operation on matrix A; factoring D into the product of two matrices, C and S.sup.T, by performing a constrained alternating least-squares analysis of D=CS.sup.T, where C is a concentration intensity matrix and S is a spectral shapes matrix; unweighting C and S by applying the inverse of the weighting used previously; and determining the properties of the sample by inspecting C and S. This method can be used to analyze X-ray spectral data generated by operating a Scanning Electron Microscope (SEM) with an attached Energy Dispersive Spectrometer (EDS).

  3. SPECTRALLY EFFICIENT MULTICARRIER SYSTEMS FOR FIBER-OPTIC TRANSMISSION

    E-Print Network [OSTI]

    Zhang, Yuanyuan

    2012-05-31

    The purpose of this research is to provide a comprehensive study of spectrally efficient multicarrier systems for fiber-optic transmission. Multicarrier optical systems partition a high-data rate digital signal in a wavelength channel into multiple...

  4. Spectral Properties of Galactic and Extragalactic Black Hole Candidates

    E-Print Network [OSTI]

    Sandip K. Chakrabarti

    1996-11-10

    We review current theoretical understanding of the spectral properties (low and high states, transition of states, quasi-periodic oscillations etc.) of the low mass as well as supermassive black hole candidates.

  5. A review of cermet-based spectrally selective solar absorbers

    E-Print Network [OSTI]

    Cao, Feng

    Spectrally selective solar absorbers harvest solar energy in the form of heat. Solar absorbers using cermet-based coatings demonstrate a high absorptance of the solar spectrum and a low emittance in the infrared (IR) regime. ...

  6. Spectral proper orthogonal decomposition

    E-Print Network [OSTI]

    Sieber, Moritz; Paschereit, Christian Oliver

    2015-01-01

    The identification of coherent structures from experimental or numerical data is an essential task when conducting research in fluid dynamics. This typically involves the construction of an empirical mode base that appropriately captures the dominant flow structures. The most prominent candidates are the energy-ranked proper orthogonal decomposition (POD) and the frequency ranked Fourier decomposition and dynamic mode decomposition (DMD). However, these methods fail when the relevant coherent structures occur at low energies or at multiple frequencies, which is often the case. To overcome the deficit of these "rigid" approaches, we propose a new method termed Spectral Proper Orthogonal Decomposition (SPOD). It is based on classical POD and it can be applied to spatially and temporally resolved data. The new method involves an additional temporal constraint that enables a clear separation of phenomena that occur at multiple frequencies and energies. SPOD allows for a continuous shifting from the energetically ...

  7. Compressive spectral method for the simulation of the water waves

    E-Print Network [OSTI]

    Cihan Bayindir

    2015-12-19

    In this paper an approach for decreasing the computational effort required for the spectral simulations of the water waves is introduced. Signals with majority of the components zero, are known as the sparse signals. Like majority of the signals in the nature it can be realized that water waves are sparse either in time or in the frequency domain. Using the sparsity property of the water waves in the time or in the frequency domain, the compressive sampling algorithm can be used as a tool for improving the performance of the spectral simulation of the water waves. The methodology offered in this paper depends on the idea of using a smaller number of spectral components compared to the classical spectral method with a high number of components. After performing the time integration with a smaller number of spectral components and using the compressive sampling technique, it is shown that the water wave field can be reconstructed with a significantly better efficiency compared to the classical spectral method with a high number of spectral components, especially for long time evolutions. For the sparse water wave model in the time domain the well-known solitary wave solutions of the Korteweg-deVries (KdV) equation is considered. For the sparse water wave model in the frequency domain the well-known Airy (linear) ocean waves with Jonswap spectrum is considered. Utilizing a spectral method, it is shown that by using a smaller number of spectral components compared to the classical spectral method with a high number of components, it is possible to simulate the sparse water waves with negligible error in accuracy and a great efficiency especially for large time evolutions.

  8. SPATIALLY-COHERENT NON-LINEAR DIMENSIONALITY REDUCTION AND SEGMENTATION OF HYPER-SPECTRAL IMAGES

    E-Print Network [OSTI]

    Minnesota, University of

    SPATIALLY-COHERENT NON-LINEAR DIMENSIONALITY REDUCTION AND SEGMENTATION OF HYPER-SPECTRAL IMAGES-Coherent Non-Linear Dimensionality Reduction and Segmentation of Hyper-Spectral Images Anish Mohan,1 Guillermo into account the non- linear nature of high dimensional hyper-spectral images, and projects onto a lower

  9. Low-Cost Spectral Sensor Development Description.

    SciTech Connect (OSTI)

    Armijo, Kenneth Miguel; Yellowhair, Julius

    2014-11-01

    Solar spectral data for all parts of the US is limited due in part to the high cost of commercial spectrometers. Solar spectral information is necessary for accurate photovoltaic (PV) performance forecasting, especially for large utility-scale PV installations. A low-cost solar spectral sensor would address the obstacles and needs. In this report, a novel low-cost, discrete- band sensor device, comprised of five narrow-band sensors, is described. The hardware is comprised of commercial-off-the-shelf components to keep the cost low. Data processing algorithms were developed and are being refined for robustness. PV module short-circuit current ( I sc ) prediction methods were developed based on interaction-terms regression methodology and spectrum reconstruction methodology for computing I sc . The results suggest the computed spectrum using the reconstruction method agreed well with the measured spectrum from the wide-band spectrometer (RMS error of 38.2 W/m 2 -nm). Further analysis of computed I sc found a close correspondence of 0.05 A RMS error. The goal is for ubiquitous adoption of the low-cost spectral sensor in solar PV and other applications such as weather forecasting.

  10. Covariance propagation in spectral indices

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Griffin, P. J.

    2015-01-09

    The dosimetry community has a history of using spectral indices to support neutron spectrum characterization and cross section validation efforts. An important aspect to this type of analysis is the proper consideration of the contribution of the spectrum uncertainty to the total uncertainty in calculated spectral indices (SIs). This study identifies deficiencies in the traditional treatment of the SI uncertainty, provides simple bounds to the spectral component in the SI uncertainty estimates, verifies that these estimates are reflected in actual applications, details a methodology that rigorously captures the spectral contribution to the uncertainty in the SI, and provides quantified examplesmore »that demonstrate the importance of the proper treatment the spectral contribution to the uncertainty in the SI.« less

  11. New Chemical Aerosol Characterization Methods- Examples Using Agricultural and Urban Airborne Particulate Matter 

    E-Print Network [OSTI]

    Zhou, Lijun

    2010-10-12

    This study explored different chemical characterization methods of agricultural and urban airborne particulate matter. Three different field campaigns are discussed. For the agricultural aerosols, measurement of the chemical ...

  12. ULTRAVIOLET RAMAN SPECTRAL SIGNATURE ACQUISITION: UV RAMAN SPECTRAL FINGERPRINTS.

    SciTech Connect (OSTI)

    SEDLACEK,III, A.J.FINFROCK,C.

    2002-09-01

    As a member of the science-support part of the ITT-lead LISA development program, BNL is tasked with the acquisition of UV Raman spectral fingerprints and associated scattering cross-sections for those chemicals-of-interest to the program's sponsor. In support of this role, the present report contains the first installment of UV Raman spectral fingerprint data on the initial subset of chemicals. Because of the unique nature associated with the acquisition of spectral fingerprints for use in spectral pattern matching algorithms (i.e., CLS, PLS, ANN) great care has been undertaken to maximize the signal-to-noise and to minimize unnecessary spectral subtractions, in an effort to provide the highest quality spectral fingerprints. This report is divided into 4 sections. The first is an Experimental section that outlines how the Raman spectra are performed. This is then followed by a section on Sample Handling. Following this, the spectral fingerprints are presented in the Results section where the data reduction process is outlined. Finally, a Photographs section is included.

  13. Inverse Spectral Problem Proof of Main Result

    E-Print Network [OSTI]

    Stanhope, Liz

    Inverse Spectral Problem Proof of Main Result Geodesics on Weighted Projective Spaces Zuoqin Wang of Main Result Inverse Spectral Geometry Main Result Inverse Spectral Geometry Manifold setting: (M, g Proof of Main Result Inverse Spectral Geometry Main Result Inverse Spectral Geometry Manifold setting

  14. The spectral irradiance traceability chain at PTB

    SciTech Connect (OSTI)

    Sperfeld, P.; Pape, S.; Nevas, S.

    2013-05-10

    Spectral irradiance is a fundamental radiometric unit. Its application to measurement results requires qualified traceability to basic units of the international system of units (Systeme international d'unites, SI). The Physikalisch-Technische Bundesanstalt (PTB) is amongst other national metrological institutes (NMIs) responsible for the realization, maintenance and dissemination of various radiometric and photometric units based on and traceable to national standards. The unit of spectral irradiance is realized and represented by a blackbody-radiator as the national primary standard of the PTB. Based on Planck's radiation law, the irradiance is calculated and realized for any wavelength taking into account the exact knowledge of the radiation temperature and the geometrical parameters. Using a double-monochromator-based spectroradiometer system, secondary standard lamps can be calibrated by direct comparison to the blackbody-radiator (substitution method). These secondary standard lamps are then used at the PTB to calibrate standard lamps of customers. The customers themselves use these so-called transfer standards to calibrate their working standard lamps. These working standards are then used to calibrate own spectroradiometers or sources. This rather complex calibration chain is a common procedural method that for the customers generally leads to satisfying measurement results on site. Nevertheless, the standard lamps in use have to fulfill highest requirements concerning stability and reproducibility. Only this allows achieving comparably low transfer measurement uncertainties, which occur at each calibration step. Thus, the PTB is constantly investigating the improvement and further development of transfer standards and measurement methods for various spectral regions. The realization and dissemination of the spectral irradiance using the blackbody-radiator at the PTB is accomplished with worldwide approved minimized measurement uncertainties confirmed by international intercomparisons among NMIs. Ultimately, the spectral irradiance can be realized with expanded measurement uncertainties of far less than 1 % over a wide spectral range. Thus, for customers with high demands on low measurement uncertainties, it is possible to calibrate their working standards directly against the blackbody-radiator, taking into account the higher necessary effort. In special cases it is possible to calibrate the customer's spectroradiometric facilities directly in front of the blackbody-radiator. In the context of the European Metrology Research Project Traceability for surface spectral solar ultraviolet radiation, the traceability chain will be improved and adapted.

  15. Analysis of mixing layer heights inferred from radiosonde, wind profiler, airborne lidar, airborne microwave temperature profiler, and in-situ aircraft data during the Texas 2000 air quality study in Houston, TX 

    E-Print Network [OSTI]

    Smith, Christina Lynn

    2005-08-29

    The mixing layer (ML) heights inferred from radiosondes, wind profilers, airborne lidar, airborne microwave temperature profiler (MTP), and in-situ aircraft data were compared during the Texas 2000 Air Quality Study in the Houston area...

  16. Method of photon spectral analysis

    DOE Patents [OSTI]

    Gehrke, Robert J. (Idaho Falls, ID); Putnam, Marie H. (Idaho Falls, ID); Killian, E. Wayne (Idaho Falls, ID); Helmer, Richard G. (Idaho Falls, ID); Kynaston, Ronnie L. (Blackfoot, ID); Goodwin, Scott G. (Idaho Falls, ID); Johnson, Larry O. (Pocatello, ID)

    1993-01-01

    A spectroscopic method to rapidly measure the presence of plutonium in soils, filters, smears, and glass waste forms by measuring the uranium L-shell x-ray emissions associated with the decay of plutonium. In addition, the technique can simultaneously acquire spectra of samples and automatically analyze them for the amount of americium and .gamma.-ray emitting activation and fission products present. The samples are counted with a large area, thin-window, n-type germanium spectrometer which is equally efficient for the detection of low-energy x-rays (10-2000 keV), as well as high-energy .gamma. rays (>1 MeV). A 8192- or 16,384 channel analyzer is used to acquire the entire photon spectrum at one time. A dual-energy, time-tagged pulser, that is injected into the test input of the preamplifier to monitor the energy scale, and detector resolution. The L x-ray portion of each spectrum is analyzed by a linear-least-squares spectral fitting technique. The .gamma.-ray portion of each spectrum is analyzed by a standard Ge .gamma.-ray analysis program. This method can be applied to any analysis involving x- and .gamma.-ray analysis in one spectrum and is especially useful when interferences in the x-ray region can be identified from the .gamma.-ray analysis and accommodated during the x-ray analysis.

  17. Method of photon spectral analysis

    DOE Patents [OSTI]

    Gehrke, R.J.; Putnam, M.H.; Killian, E.W.; Helmer, R.G.; Kynaston, R.L.; Goodwin, S.G.; Johnson, L.O.

    1993-04-27

    A spectroscopic method to rapidly measure the presence of plutonium in soils, filters, smears, and glass waste forms by measuring the uranium L-shell x-ray emissions associated with the decay of plutonium. In addition, the technique can simultaneously acquire spectra of samples and automatically analyze them for the amount of americium and [gamma]-ray emitting activation and fission products present. The samples are counted with a large area, thin-window, n-type germanium spectrometer which is equally efficient for the detection of low-energy x-rays (10-2,000 keV), as well as high-energy [gamma] rays (>1 MeV). A 8,192- or 16,384 channel analyzer is used to acquire the entire photon spectrum at one time. A dual-energy, time-tagged pulser, that is injected into the test input of the preamplifier to monitor the energy scale, and detector resolution. The L x-ray portion of each spectrum is analyzed by a linear-least-squares spectral fitting technique. The [gamma]-ray portion of each spectrum is analyzed by a standard Ge [gamma]-ray analysis program. This method can be applied to any analysis involving x- and [gamma]-ray analysis in one spectrum and is especially useful when interferences in the x-ray region can be identified from the [gamma]-ray analysis and accommodated during the x-ray analysis.

  18. On the regular slice spectral sequence

    E-Print Network [OSTI]

    Ullman, John Richard

    2013-01-01

    In this thesis, we analyze a variant of the slice spectral sequence of [HHR (or SSS) called the regular slice spectral sequence (or RSSS). This latter spectral sequence is defined using only the regular slice cells. We ...

  19. Prospecting by sampling and analysis of airborne particulates and gases

    DOE Patents [OSTI]

    Sehmel, G.A.

    1984-05-01

    A method is claimed for prospecting by sampling airborne particulates or gases at a ground position and recording wind direction values at the time of sampling. The samples are subsequently analyzed to determine the concentrations of a desired material or the ratios of the desired material to other identifiable materials in the collected samples. By comparing the measured concentrations or ratios to expected background data in the vicinity sampled, one can select recorded wind directions indicative of the upwind position of the land-based source of the desired material.

  20. ARM - Evaluation Product - Airborne Visible/Infrared Imaging Spectrometer

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Comments? WeDatastreamstps DocumentationAtlanticENA Contacts ENA Related Links(AVIRIS) ProductsAirborne

  1. Category:Airborne Gravity Survey | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION JEnvironmentalBowerbank,Cammack Village,8199089°, -86.3376761°AnadromousASHRAEAirborneAirborne

  2. Evaluation of Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) and Moderate Resolution Imaging Spectrometer

    E-Print Network [OSTI]

    Evaluation of Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) and Moderate Resolution the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) and the Moderate Resolution Imaging Spectrometer (MODIS). Key goals were to assess the nature of these relationships as they varied between sensors

  3. Non-contact thermoacoustic detection of embedded targets using airborne-capacitive micromachined ultrasonic transducers

    E-Print Network [OSTI]

    Khuri-Yakub, Butrus T. "Pierre"

    Non-contact thermoacoustic detection of embedded targets using airborne-capacitive micromachined to IP: 171.64.84.210 On: Thu, 26 Feb 2015 05:19:31 #12;Non-contact thermoacoustic detection of embedded provides permittivity contrast, and ultra- sensitive airborne-ultrasound detection measures thermoacoustic

  4. Airborne MAX-DOAS measurements over California: Testing the NASA OMI tropospheric NO2 product

    E-Print Network [OSTI]

    Airborne MAX-DOAS measurements over California: Testing the NASA OMI tropospheric NO2 product Hilke] Airborne Multi-AXis Differential Optical Absorption Spectroscopy (AMAX-DOAS) measurements of NO2 are compared to the NASA Ozone Monitoring Instrument (OMI) tropospheric vertical columns (data product v2

  5. Near-coastal surface water velocity field estimation using airborne remote sensing11

    E-Print Network [OSTI]

    Near-coastal surface water velocity field estimation using airborne remote sensing11 Tim J Malthus1. With airborne remote sensing, however, it is possible to determine synoptic changes in velocity fields because properties of successive remotely sensed images may be used to estimate velocity vectors associated

  6. Biomass and Bioenergy 31 (2007) 646655 Estimating biomass of individual pine trees using airborne lidar

    E-Print Network [OSTI]

    2007-01-01

    Biomass and Bioenergy 31 (2007) 646­655 Estimating biomass of individual pine trees using airborne biomass and bio-energy feedstocks. The overall goal of this study was to develop a method for assessing aboveground biomass and component biomass for individual trees using airborne lidar data in forest settings

  7. Spectral Measures for $Sp(2)$

    E-Print Network [OSTI]

    David E. Evans; Mathew Pugh

    2015-02-13

    Spectral measures provide invariants for braided subfactors via fusion modules. In this paper we study joint spectral measures associated to the compact connected rank two Lie group $SO(5)$ and its double cover the compact connected, simply-connected rank two Lie group $Sp(2)$, including the McKay graphs for the irreducible representations of $Sp(2)$ and $SO(5)$ and their maximal tori, and fusion modules associated to the $Sp(2)$ modular invariants.

  8. Analyses of in-situ airborne volcanic ash from the February 2000 eruption of Hekla Volcano, Iceland

    E-Print Network [OSTI]

    Ma, Chi

    Analyses of in-situ airborne volcanic ash from the February 2000 eruption of Hekla Volcano, Iceland-8 NASA research aircraft inadvertently flew into an airborne volcanic ash plume from the 26 February spectrophotometer analyses. These analyses confirm that the DC-8 encountered airborne volcanic ash from Hekla

  9. Estimated airborne release of plutonium from Atomics International's Nuclear Materials Development Facility in the Santa Susana site, California, as a result of postulated damage from severe wind and earthquake hazard

    SciTech Connect (OSTI)

    Mishima, J.; Ayer, J.E.

    1981-09-01

    The potential mass of airborne releases of plutonium (source term) that could result from wind and seismic damage is estimated for the Atomics International Company's Nuclear Materials Development Facility (NMDF) at the Santa Susana site in California. The postulated source terms will be useful as the basis for estimating the potential dose to the maximum exposed individual by inhalation and to the total population living within a prescribed radius of the site. The respirable fraction of airborne particles is thus the principal concern. The estimated source terms are based on the damage ratio, and the potential airborne releases if all enclosures suffer particular levels of damage. In an attempt to provide a realistic range of potential source terms that include most of the normal processing conditions, a best estimate bounded by upper and lower limits is provided. The range of source terms is calculated by combining a high best estimate and a low damage ratio, based on a fraction of enclosures suffering crush or perforation, with the airborne release from enclosures based upon an upper limit, average, and lower limit inventory of dispersible materials at risk. Two throughput levels are considered. The factors used to evaluate the fractional airborne release of materials and the exchange rates between enclosed and exterior atmospheres are discussed. The postulated damage and source terms are discussed for wind and earthquake hazard scenarios in order of their increasing severity.

  10. Hard and soft spectral states of ULXs

    E-Print Network [OSTI]

    Soria, Roberto

    2010-01-01

    I discuss some differences between the observed spectral states of ultraluminous X-ray sources (ULXs) and the canonical scheme of spectral states defined in Galactic black holes. The standard interpretation of ULXs with a curved spectrum, or a moderately steep power-law with soft excess and high-energy downturn, is that they are an extension of the very high state, up to luminosities ~ 1 to 3 L_{Edd}. Two competing models are Comptonization in a warm corona, and slim disk; I suggest bulk motion Comptonization in the radiatively-driven outflow as another possibility. The interpretation of ULXs with a hard power-law spectrum is more problematic. Some of them remain in that state over a large range of luminosities; others switch directly to a curved state without going through a canonical high/soft state. I suggest that those ULXs are in a high/hard state not seen in Galactic black holes; that state may overlap with the low/hard state at lower accretion rates, and extend all the way to Eddington accretion rates....

  11. EFFICIENT SPECTRAL-GALERKIN METHODS FOR FRACTIONAL ...

    E-Print Network [OSTI]

    2015-11-17

    EFFICIENT SPECTRAL-GALERKIN METHODS FOR FRACTIONAL PARTIAL. DIFFERENTIAL EQUATIONS WITH VARIABLE COEFFICIENTS. ZHIPING MAO†

  12. Initial assessment of an airborne Ku-band polarimetric SAR.

    SciTech Connect (OSTI)

    Raynal, Ann Marie; Doerry, Armin Walter

    2013-02-01

    Polarimetric synthetic aperture radar (SAR) has been used for a variety of dual-use research applications since the 1940's. By measuring the direction of the electric field vector from radar echoes, polarimetry may enhance an analyst's understanding of scattering effects for both earth monitoring and tactical surveillance missions. Polarimetry may provide insight into surface types, materials, or orientations for natural and man-made targets. Polarimetric measurements may also be used to enhance the contrast between scattering surfaces such as man-made objects and their surroundings. This report represents an initial assessment of the utility of, and applications for, polarimetric SAR at Ku-band for airborne or unmanned aerial systems.

  13. Method for measuring the size distribution of airborne rhinovirus

    SciTech Connect (OSTI)

    Russell, M.L.; Goth-Goldstein, R.; Apte, M.G.; Fisk, W.J.

    2002-01-01

    About 50% of viral-induced respiratory illnesses are caused by the human rhinovirus (HRV). Measurements of the concentrations and sizes of bioaerosols are critical for research on building characteristics, aerosol transport, and mitigation measures. We developed a quantitative reverse transcription-coupled polymerase chain reaction (RT-PCR) assay for HRV and verified that this assay detects HRV in nasal lavage samples. A quantitation standard was used to determine a detection limit of 5 fg of HRV RNA with a linear range over 1000-fold. To measure the size distribution of HRV aerosols, volunteers with a head cold spent two hours in a ventilated research chamber. Airborne particles from the chamber were collected using an Andersen Six-Stage Cascade Impactor. Each stage of the impactor was analyzed by quantitative RT-PCR for HRV. For the first two volunteers with confirmed HRV infection, but with mild symptoms, we were unable to detect HRV on any stage of the impactor.

  14. Apparatus and methods for monitoring the concentrations of hazardous airborne substances, especially lead

    DOE Patents [OSTI]

    Zaromb, Solomon

    2004-07-13

    Air is sampled at a rate in excess of 100 L/min, preferably at 200-300 L/min, so as to collect therefrom a substantial fraction, i.e., at least 20%, preferably 60-100%, of airborne particulates. A substance of interest (analyte), such as lead, is rapidly solubilized from the the collected particulates into a sample of liquid extractant, and the concentration of the analyte in the extractant sample is determined. The high-rate air sampling and particulate collection may be effected with a high-throughput filter cartridge or with a recently developed portable high-throughput liquid-absorption air sampler. Rapid solubilization of lead is achieved by a liquid extractant comprising 0.1-1 M of acetic acid or acetate, preferably at a pH of 5 or less and preferably with inclusion of 1-10% of hydrogen peroxide. Rapid determination of the lead content in the liquid extractant may be effected with a colorimetric or an electroanalytical analyzer.

  15. Compressive spectral method for the simulation of the water waves

    E-Print Network [OSTI]

    Bayindir, Cihan

    2015-01-01

    In this paper an approach for decreasing the computational effort required for the spectral simulations of the water waves is introduced. Signals with majority of the components zero, are known as the sparse signals. Like majority of the signals in the nature it can be realized that water waves are sparse either in time or in the frequency domain. Using the sparsity property of the water waves in the time or in the frequency domain, the compressive sampling algorithm can be used as a tool for improving the performance of the spectral simulation of the water waves. The methodology offered in this paper depends on the idea of using a smaller number of spectral components compared to the classical spectral method with a high number of components. After performing the time integration with a smaller number of spectral components and using the compressive sampling technique, it is shown that the water wave field can be reconstructed with a significantly better efficiency compared to the classical spectral method w...

  16. Methods for spectral image analysis by exploiting spatial simplicity

    DOE Patents [OSTI]

    Keenan, Michael R.

    2010-05-25

    Several full-spectrum imaging techniques have been introduced in recent years that promise to provide rapid and comprehensive chemical characterization of complex samples. One of the remaining obstacles to adopting these techniques for routine use is the difficulty of reducing the vast quantities of raw spectral data to meaningful chemical information. Multivariate factor analysis techniques, such as Principal Component Analysis and Alternating Least Squares-based Multivariate Curve Resolution, have proven effective for extracting the essential chemical information from high dimensional spectral image data sets into a limited number of components that describe the spectral characteristics and spatial distributions of the chemical species comprising the sample. There are many cases, however, in which those constraints are not effective and where alternative approaches may provide new analytical insights. For many cases of practical importance, imaged samples are "simple" in the sense that they consist of relatively discrete chemical phases. That is, at any given location, only one or a few of the chemical species comprising the entire sample have non-zero concentrations. The methods of spectral image analysis of the present invention exploit this simplicity in the spatial domain to make the resulting factor models more realistic. Therefore, more physically accurate and interpretable spectral and abundance components can be extracted from spectral images that have spatially simple structure.

  17. The spectral evolution of impulsive solar X-ray flares

    E-Print Network [OSTI]

    Paolo C. Grigis; Arnold O. Benz

    2004-07-20

    The time evolution of the spectral index and the non-thermal flux in 24 impulsive solar hard X-ray flares of GOES class M was studied in RHESSI observations. The high spectral resolution allows for a clean separation of thermal and non-thermal components in the 10-30 keV range, where most of the non-thermal photons are emitted. Spectral index and flux can thus be determined with much better accuracy than before. The spectral soft-hard-soft behavior in rise-peak-decay phases is discovered not only in the general flare development, but even more pronounced in subpeaks. An empirically found power-law dependence between the spectral index and the normalization of the non-thermal flux holds during the rise and decay phases of the emission peaks. It is still present in the combined set of all flares. We find an asymmetry in this dependence between rise and decay phases of the non-thermal emission. There is no delay between flux peak and spectral index minimum. The soft-hard-soft behavior appears to be an intrinsic signature of the elementary electron acceleration process.

  18. Methods for spectral image analysis by exploiting spatial simplicity

    DOE Patents [OSTI]

    Keenan, Michael R. (Albuquerque, NM)

    2010-11-23

    Several full-spectrum imaging techniques have been introduced in recent years that promise to provide rapid and comprehensive chemical characterization of complex samples. One of the remaining obstacles to adopting these techniques for routine use is the difficulty of reducing the vast quantities of raw spectral data to meaningful chemical information. Multivariate factor analysis techniques, such as Principal Component Analysis and Alternating Least Squares-based Multivariate Curve Resolution, have proven effective for extracting the essential chemical information from high dimensional spectral image data sets into a limited number of components that describe the spectral characteristics and spatial distributions of the chemical species comprising the sample. There are many cases, however, in which those constraints are not effective and where alternative approaches may provide new analytical insights. For many cases of practical importance, imaged samples are "simple" in the sense that they consist of relatively discrete chemical phases. That is, at any given location, only one or a few of the chemical species comprising the entire sample have non-zero concentrations. The methods of spectral image analysis of the present invention exploit this simplicity in the spatial domain to make the resulting factor models more realistic. Therefore, more physically accurate and interpretable spectral and abundance components can be extracted from spectral images that have spatially simple structure.

  19. POLYPHONIC INSTRUMENT RECOGNITION SPECTRAL CLUSTERING

    E-Print Network [OSTI]

    Tzanetakis, George

    POLYPHONIC INSTRUMENT RECOGNITION USING SPECTRAL CLUSTERING Luis Gustavo Martins Telecommunications]@uvic.ca ABSTRACT The identification of the instruments playing in a poly- phonic music signal is an important source separation and tim- bre classification of polyphonic, multi-instrumental music signals. The sound

  20. BEO Tram Spectral Data 2014

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Torn, Margaret; Serbin, Shawn

    Visible to near-infrared (350-1100nm) vegetation spectral reflectance data collected on the BEO automated tram measurement platform during the 2014 growing season. The spectra were collected using a PP Systems UniSpec-DC instrument and was processed to at-surface reflectance and interpolated to 1nm.

  1. BEO Tram Spectral Data 2014

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Torn, Margaret; Serbin, Shawn

    2015-06-10

    Visible to near-infrared (350-1100nm) vegetation spectral reflectance data collected on the BEO automated tram measurement platform during the 2014 growing season. The spectra were collected using a PP Systems UniSpec-DC instrument and was processed to at-surface reflectance and interpolated to 1nm.

  2. Spectral Modeling Hot Star Winds

    E-Print Network [OSTI]

    Cohen, David

    Spectral Modeling of X-Rays from Hot Star Winds Emma Wollman Advisor: David Cohen #12;Hot Stars ·· Short-livedShort-lived (~ 1-10 million yrs)(~ 1-10 million yrs) #12;Stellar Winds · Net momentum · More luminosity !"stronger wind · Mass-loss rate determines the fate of the star #12;X-ray Production

  3. ARM Climate Research Facility Spectral Surface Albedo Value-Added Product (VAP) Report

    SciTech Connect (OSTI)

    McFarlane, S; Gaustad, K; Long, C; Mlawer, E

    2011-07-15

    This document describes the input requirements, output data products, and methodology for the Spectral Surface Albedo (SURFSPECALB) value-added product (VAP). The SURFSPECALB VAP produces a best-estimate near-continuous high spectral resolution albedo data product using measurements from multifilter radiometers (MFRs). The VAP first identifies best estimates for the MFR downwelling and upwelling shortwave irradiance values, and then calculates narrowband spectral albedo from these best-estimate irradiance values. The methodology for finding the best-estimate values is based on a simple process of screening suspect data and backfilling screened and missing data with estimated values when possible. The resulting best-estimate MFR narrowband spectral albedos are used to determine a daily surface type (snow, 100% vegetation, partial vegetation, or 0% vegetation). For non-snow surfaces, a piecewise continuous function is used to estimate a high spectral resolution albedo at 1 min temporal and 10 cm-1 spectral resolution.

  4. Primer on Use of Multi-Spectral and Infra Red Imaging for On-Site Inspections

    SciTech Connect (OSTI)

    Henderson, J R

    2010-10-26

    The purpose of an On-Site Inspection (OSI) is to determine whether a nuclear explosion has occurred in violation of the Comprehensive Nuclear Test Ban Treaty (CTBT), and to gather information which might assist in identifying the violator (CTBT, Article IV, Paragraph 35) Multi-Spectral and Infra Red Imaging (MSIR) is allowed by the treaty to detect observables which might help reduce the search area and thus expedite an OSI and make it more effective. MSIR is permitted from airborne measurements, and at and below the surface to search for anomalies and artifacts (CTBT, Protocol, Part II, Paragraph 69b). The three broad types of anomalies and artifacts MSIR is expected to be capable of observing are surface disturbances (disturbed earth, plant stress or anomalous surface materials), human artifacts (man-made roads, buildings and features), and thermal anomalies. The purpose of this Primer is to provide technical information on MSIR relevant to its use for OSI. It is expected that this information may be used for general background information, to inform decisions about the selection and testing of MSIR equipment, to develop operational guidance for MSIR use during an OSI, and to support the development of a training program for OSI Inspectors. References are provided so readers can pursue a topic in more detail than the summary information provided here. The following chapters will provide more information on how MSIR can support an OSI (Section 2), a short summary what Multi-Spectral Imaging and Infra Red Imaging is (Section 3), guidance from the CTBT regarding the use of MSIR (Section 4), and a description of several nuclear explosion scenarios (Section 5) and consequent observables (Section 6). The remaining sections focus on practical aspects of using MSIR for an OSI, such as specification and selection of MSIR equipment, operational considerations for deployment of MISR equipment from an aircraft, and the conduct of field exercises to mature MSIR for an OSI. Finally, an appendix provides detail describing the magnitude and spatial extent of the surface shock expected from an underground nuclear explosion. If there is a seismic event or other data to suggest there has been a nuclear explosion in violation of the CTBT, an OSI may be conducted to determine whether a nuclear explosion has occurred and to gather information which may be useful in identifying the party responsible for conducting the explosion. The OSI must be conducted in the area where the event that triggered the inspection request occurred, and the inspected area must not exceed 1,000 square kilometers, or be more than 50 km on aside (CTBT Protocol, Part II, Paragraphs 2 and 3). One of the guiding principles for an inspection is that it be effective, minimally intrusive, timely, and cost-effective [Hawkins, Feb 1998]. In that context, MSIR is one of several technologies that can be used during an aircraft overflight to identify ground regions of high interest in a timely and cost-effective manner. This allows for an optimized inspection on the ground. The primary purpose for MSIR is to identify artifacts and anomalies that might be associated with a nuclear explosion, and to use the location of those artifacts and anomalies to reduce the search area that must be inspected from the ground. The MSIR measurements can have additional utility. The multi-spectral measurements of the ground can be used for terrain classification, which can aid in geological characterization of the Inspected Area. In conditions of where light smoke or haze is present, long-wave infrared imaging can provide better imaging of the ground than is possible with standard visible imagery.

  5. Multisensor Fusion of Ground-based and Airborne Remote Sensing Data for Crop Condition Assessment 

    E-Print Network [OSTI]

    Zhang, Huihui

    2012-02-14

    provide applicators with guidance equipment configurations that can result in herbicide savings and optimized applications in other crops. The main focus of this research was to apply sensor fusion technology to ground-based and airborne imagery data...

  6. Positioning in geophysics : applications to GPS seismology, airborne gravimetry, and the Dawn Spacecraft at Vesta

    E-Print Network [OSTI]

    Centinello, Frank Joseph, III

    2015-01-01

    This dissertation presents improvements made on position estimation techniques applied to seismology, airborne gravimetry and planetary gravity recovery. In Chapters 2 and 3, a smoothed ionospheric model computed using GPS ...

  7. Implementing technical transitions through schedule-based policy : insights from the Military's Airborne Tactical Network

    E-Print Network [OSTI]

    Rohrbach, Amanda K. (Amanda Kaye)

    2013-01-01

    Due to a need for congestion relief, as well as a projected increase in capacity constraints, the US Military's Airborne Tactical Network (ATN) is at the onset of a technical transition of their communication hardware and ...

  8. BNL-67857-AB AIRBORNE FORMALDEHYDE MEASUREMENT ON A NOAA WP-3 DURING THE 1999

    E-Print Network [OSTI]

    BNL-67857-AB AIRBORNE FORMALDEHYDE MEASUREMENT ON A NOAA WP-3 DURING THE 1999 SOS SUMMER FIELD, San Francisco, CA, Dec. 15-19, 2000. Atmospheric formaldehyde (HCHO) concentration was determined

  9. The metal content of airborne particles in Edinburgh: application to epidemiological research 

    E-Print Network [OSTI]

    Hibbs, L R; Beverland, Iain J; Heal, Mathew R; Agius, Raymond M; Elton, Robert A; Fowler, D; Cape, Neil

    2002-01-01

    Metals are putative causative agents in the association between ill health and exposure to airborne particles. We present preliminary results from an epidemiological study using exposure metrics of metal contained in ...

  10. Airborne release fractions/rates and respirable fractions for nonreactor nuclear facilities. Volume 2, Appendices

    SciTech Connect (OSTI)

    Not Available

    1994-12-01

    This document contains compiled data from the DOE Handbook on Airborne Release Fractions/Rates and Respirable Fractions for Nonreactor Nuclear facilities. Source data and example facilities utilized, such as the Plutonium Recovery Facility, are included.

  11. Using Airborne Sensing to Map Pools in Rivers

    E-Print Network [OSTI]

    Walker, Jeff

    Surveys ­ Advantages: Extensive coverages, low cost for existing products ­ Disadvantage: Low resolution-Spectral Line Scanner 1.0m pixels 1250m swath width Raster files #12;LIDAR 1m point spacing 600m swath width only Follow river Follow river where access possible 10-20 300-600 ·Possibility of automation ·Manual

  12. Spectral Emission of Moving Atom

    E-Print Network [OSTI]

    J. X. Zheng-Johansson

    2008-03-17

    A renewed analysis of the H.E. Ives and G.R. Stilwell's experiment on moving hydrogen canal rays (J. Opt. Soc. Am., 1938, v.28, 215) concludes that the spectral emission of a moving atom exhibits always a redshift which informs not the direction of the atom's motion. The conclusion is also evident from a simple energy relation: atomic spectral radiation is emitted as an orbiting electron consumes a portion of its internal energy on transiting to a lower-energy state which however has in a moving atom an additional energy gain; this results in a redshift in the emission frequency. Based on auxiliary experimental information and a scheme for de Broglie particle formation, we give a vigorous elucidation of the mechanism for deceleration radiation of atomic electron; the corresponding prediction of the redshift is in complete agreement with the Ives and Stilwell's experimental formula.

  13. AN EFFICIENT AND ACCURATE SPECTRAL METHOD FOR ...

    E-Print Network [OSTI]

    2009-01-20

    AN EFFICIENT AND ACCURATE SPECTRAL METHOD FOR. ACOUSTIC SCATTERING IN ELLIPTIC DOMAINS. QIRONG FANG†. JIE SHEN†. AND LI-

  14. Spectral averaging techniques for Jacobi matrices

    E-Print Network [OSTI]

    Rafael del Rio; Carmen Martinez; Hermann Schulz-Baldes

    2008-02-20

    Spectral averaging techniques for one-dimensional discrete Schroedinger operators are revisited and extended. In particular, simultaneous averaging over several parameters is discussed. Special focus is put on proving lower bounds on the density of the averaged spectral measures. These Wegner type estimates are used to analyze stability properties for the spectral types of Jacobi matrices under local perturbations.

  15. X-ray spectral states of microquasars

    E-Print Network [OSTI]

    Julien Malzac; Renaud Belmont

    2008-10-25

    We discuss the origin of the dramatically different X-ray spectral shapes observed in the Low Hard State (LHS: dominated by thermal comptonisation) and the High Soft State (HSS: dominated by the accretion disc thermal emission and non-thermal comptonisation in the corona). We present numerical simulations using a new code accounting for the so-called synchrotron boiler effect. These numerical simulations when compared to the data allow us to constrain the magnetic field and temperature of the hot protons in the corona. For the hard state of Cygnus X-1 we find a magnetic field below equipartition with radiation, suggesting that the corona is not powered through magnetic field dissipation (as assumed in most accretion disc corona models). On the other hand, our results also point toward proton temperatures that are substantially lower than typical temperatures of the ADAF models. Finally, we show that in both spectral states Comptonising plasma could be powered essentially through power-law acceleration of non-thermal electrons, which are then partly thermalised by the synchrotron and Coulomb boiler. This suggests that, contrary to current beliefs, the corona of the HSS and that of the LHS could be of very similar nature. The differences between the LHS and HSS coronal spectra would then be predominantly caused by the strong disc soft cooling emission which is present in the HSS and absent in the LHS.

  16. Measuring primordial anisotropic correlators with CMB spectral distortions

    E-Print Network [OSTI]

    Maresuke Shiraishi; Michele Liguori; Nicola Bartolo; Sabino Matarrese

    2015-10-04

    We show that inflationary models with broken rotational invariance generate testable off-diagonal signatures in the correlation between the $\\mu$-type distortion and temperature fluctuations of the cosmic microwave background. More precisely, scenarios with a quadrupolar bispectrum asymmetry, usually generated by fluctuations of primordial vector fields, produce a nonvanishing $\\mu$-$T$ correlation when $|\\ell_1-\\ell_2|=2$. Since spectral distortions are sensitive to primordial fluctuations up to very small scales, a cosmic variance limited spectral distortion experiment can detect such effects with a high signal-to-noise ratio.

  17. Airborne radioactive effluent study at the Savannah River Plant

    SciTech Connect (OSTI)

    Blanchard, R.L.; Broadway, J.A.; Sensintaffar, E.L.; Kirk, W.P.; Kahn, B.; Garrett, A.J.

    1984-07-01

    Under the Clean Air Act, Sections 112 and 122 as amended in 1977, the Office of Radiation Programs (OPR) of the United States Environmental Protection Agency is currently developing standards for radionuclides emitted to the air by several source categories. In order to confirm source-term measurements and pathway calculations for radiation exposures to humans offsite, the ORP performs field studies at selected facilities that emit radionuclides. This report describes the field study conducted at the Savannah River Plant (SRP), a laboratory operated by E.I. du Pont de Nemours and Company for the US Department of Energy. This purpose of the study at ARP was to verify reported airborne releases and resulting radiation doses from the facility. Measurements of radionuclide releases for brief periods were compared with measurements performed by SRP staff on split samples and with annual average releases reported by SRP for the same facilities. The dispersion model used by SRP staff to calculate radiation doses offsite was tested by brief environmental radioactivity measurements performed simultaneously with the release measurements, and by examining radioactivity levels in environmental samples. This report describes in detail all measurements made and data collected during the field study and presents the results obtained. 34 references, 18 figures, 49 tables.

  18. The Effect of Grain Size on Spectral Mixture Analysis of Snow-Covered Area from

    E-Print Network [OSTI]

    Dozier, Jeff

    The Effect of Grain Size on Spectral Mixture Analysis of Snow-Covered Area from AVIRIS Data Thomas to improve spectral mixture Results were verified with a high spatial resolution aerial analysis of snow of multiple snow endmembers. Snow reflectance of fraction under/overflow and residuals confirmed mix- in near

  19. EFFECTS OF CHANGING SPECTRAL RADIATION DISTRIBUTION ON THE PERFORMANCE OF PHOTODIODE PYRANOMETERS

    E-Print Network [OSTI]

    Oregon, University of

    , they are a fraction of the cost of a high quality solar monitoring sta- tion. The main weakness with the RSI of the LI-COR photodiode pyranometer is examined, using DNI spectral data from a PMOD Spectroradiometer Irradiometers. Similar methodol- ogy can be used to estimate the spectral effect on the per- formance of solar

  20. Vibrational Lifetimes and Spectral Shifts in Supercritical Fluids as a Function of Density: Experiments and Theory

    E-Print Network [OSTI]

    Fayer, Michael D.

    (CO2) as a function of density from low density (well below the critical density) to high densityVibrational Lifetimes and Spectral Shifts in Supercritical Fluids as a Function of Density Vibrational lifetime and spectral shift data for the asymmetric CO stretching mode of W(CO)6 in supercritical

  1. THE BATSE 5B GAMMA-RAY BURST SPECTRAL CATALOG

    SciTech Connect (OSTI)

    Goldstein, Adam; Preece, Robert D.; Briggs, Michael S.; Burgess, J. Michael [University of Alabama in Huntsville, 320 Sparkman Drive, Huntsville, AL 35899 (United States); Mallozzi, Robert S.; Fishman, Gerald J.; Kouveliotou, Chryssa [Space Science Office, VP62, NASA/Marshall Space Flight Center, Huntsville, AL 35812 (United States); Paciesas, William S. [Universities Space Research Association, 320 Sparkman Drive, Huntsville, AL 35805 (United States)

    2013-10-01

    We present systematic spectral analyses of gamma-ray bursts (GRBs) detected with the Burst and Transient Source Experiment (BATSE) on board the Compton Gamma-Ray Observatory during its entire nine years of operation. This catalog contains two types of spectra extracted from 2145 GRBs, and fitted with five different spectral models resulting in a compendium of over 19,000 spectra. The models were selected based on their empirical importance to the spectral shape of many GRBs, and the analysis performed was devised to be as thorough and objective as possible. We describe in detail our procedures and criteria for the analyses, and present the bulk results in the form of parameter distributions. This catalog should be considered an official product from the BATSE Science Team, and the data files containing the complete results are available from the High-Energy Astrophysics Science Archive Research Center (HEASARC)

  2. Chemical and isotopic properties and origin of coarse airborne particles collected by passive samplers in industrial, urban, and rural environments

    E-Print Network [OSTI]

    Short, Daniel

    Chemical and isotopic properties and origin of coarse airborne particles collected by passive vehicle and industrial emissions, coal combustion (e.g. cooking, heating, power plants) represents

  3. A new scoring function for top-down spectral deconvolution

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kou, Qiang; Wu, Si; Liu, Xiaowen

    2014-12-18

    Background: Top-down mass spectrometry plays an important role in intact protein identification and characterization. Top-down mass spectra are more complex than bottom-up mass spectra because they often contain many isotopomer envelopes from highly charged ions, which may overlap with one another. As a result, spectral deconvolution, which converts a complex top-down mass spectrum into a monoisotopic mass list, is a key step in top-down spectral interpretation. Results: In this paper, we propose a new scoring function, L-score, for evaluating isotopomer envelopes. By combining L-score with MS-Deconv, a new software tool, MS-Deconv+, was developed for top-down spectral deconvolution. Experimental results showedmore »that MS-Deconv+ outperformed existing software tools in top-down spectral deconvolution. Conclusions: L-score shows high discriminative ability in identification of isotopomer envelopes. Using L-score, MS-Deconv+ reports many correct monoisotopic masses missed by other software tools, which are valuable for proteoform identification and characterization.« less

  4. A new scoring function for top-down spectral deconvolution

    SciTech Connect (OSTI)

    Kou, Qiang [Indiana Univ.-Purdue Univ. Indianapolis, Indianapolis, IN (United States); Wu, Si [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Liu, Xiaowen [Indiana Univ. School of Medicine, Indianapolis, IN (United States)

    2014-12-18

    Background: Top-down mass spectrometry plays an important role in intact protein identification and characterization. Top-down mass spectra are more complex than bottom-up mass spectra because they often contain many isotopomer envelopes from highly charged ions, which may overlap with one another. As a result, spectral deconvolution, which converts a complex top-down mass spectrum into a monoisotopic mass list, is a key step in top-down spectral interpretation. Results: In this paper, we propose a new scoring function, L-score, for evaluating isotopomer envelopes. By combining L-score with MS-Deconv, a new software tool, MS-Deconv+, was developed for top-down spectral deconvolution. Experimental results showed that MS-Deconv+ outperformed existing software tools in top-down spectral deconvolution. Conclusions: L-score shows high discriminative ability in identification of isotopomer envelopes. Using L-score, MS-Deconv+ reports many correct monoisotopic masses missed by other software tools, which are valuable for proteoform identification and characterization.

  5. Hybrid least squares multivariate spectral analysis methods

    DOE Patents [OSTI]

    Haaland, David M.

    2004-03-23

    A set of hybrid least squares multivariate spectral analysis methods in which spectral shapes of components or effects not present in the original calibration step are added in a following prediction or calibration step to improve the accuracy of the estimation of the amount of the original components in the sampled mixture. The hybrid method herein means a combination of an initial calibration step with subsequent analysis by an inverse multivariate analysis method. A spectral shape herein means normally the spectral shape of a non-calibrated chemical component in the sample mixture but can also mean the spectral shapes of other sources of spectral variation, including temperature drift, shifts between spectrometers, spectrometer drift, etc. The shape can be continuous, discontinuous, or even discrete points illustrative of the particular effect.

  6. Hybrid least squares multivariate spectral analysis methods

    DOE Patents [OSTI]

    Haaland, David M. (Albuquerque, NM)

    2002-01-01

    A set of hybrid least squares multivariate spectral analysis methods in which spectral shapes of components or effects not present in the original calibration step are added in a following estimation or calibration step to improve the accuracy of the estimation of the amount of the original components in the sampled mixture. The "hybrid" method herein means a combination of an initial classical least squares analysis calibration step with subsequent analysis by an inverse multivariate analysis method. A "spectral shape" herein means normally the spectral shape of a non-calibrated chemical component in the sample mixture but can also mean the spectral shapes of other sources of spectral variation, including temperature drift, shifts between spectrometers, spectrometer drift, etc. The "shape" can be continuous, discontinuous, or even discrete points illustrative of the particular effect.

  7. *Corresponding author, E-mail: ndelucca@nd.edu The Airborne Aero-Optics Laboratory, Recent Data

    E-Print Network [OSTI]

    Gordeyev, Stanislav

    *Corresponding author, E-mail: ndelucca@nd.edu The Airborne Aero-Optics Laboratory, Recent Data, Notre Dame, IN USA 46556 ABSTRACT In this paper recent in-flight aero-optical measurements on the Airborne Aero-Optics Laboratory (AAOL) will be given. Instrumentation and experimental set

  8. Airborne Sun photometer measurements of aerosol optical depth and columnar water vapor during the Puerto Rico Dust Experiment and

    E-Print Network [OSTI]

    Christopher, Sundar A.

    Airborne Sun photometer measurements of aerosol optical depth and columnar water vapor during to within 0.004­0.030 with coincident data obtained with an AERONET Sun/ sky radiometer located on Cabras Dynamics: Remote sensing; KEYWORDS: PRIDE, airborne Sun photometer, aerosol optical depth, columnar water

  9. Higher-Order Spectral/HP Finite Element Technology for Structures and Fluid Flows 

    E-Print Network [OSTI]

    Vallala, Venkat Pradeep

    2013-06-20

    This study deals with the use of high-order spectral/hp approximation functions in the ?nite element models of various nonlinear boundary-value and initial-value problems arising in the ?elds of structural mechanics and ...

  10. Monolithically integrated near-infrared and mid-infrared detector array for spectral imaging

    E-Print Network [OSTI]

    Perera, A. G. Unil

    detector test results ensure the high quality of material suitable for near-infrared/QWIP dual-band focal. A CTIS records spatial and spectral information by imaging a scene through an optical relay system

  11. Holographic Quenches and Fermionic Spectral Functions

    E-Print Network [OSTI]

    N. Callebaut; B. Craps; F. Galli; D. C. Thompson; J. Vanhoof; J. Zaanen; Hongbao Zhang

    2014-11-04

    Using holographic methods we investigate the behaviour of fermionic spectral functions of strongly coupled 2+1 dimensional field theories as both temperature and chemical potential are quenched.

  12. Spectral Solar Radiation Data Base at NREL

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    *In September 1991 the Solar Energy Research Institute became the National Renewable Energy Laboratory. [Description taken from http://rredc.nrel.gov/solar/old_data/spectral/

  13. Pulsed mid-infrared radiation from spectral broadening in laser wakefield simulations

    SciTech Connect (OSTI)

    Zhu, W.; Palastro, J. P.; Antonsen, T. M. [IREAP, University of Maryland, College Park, Maryland 20740 (United States)] [IREAP, University of Maryland, College Park, Maryland 20740 (United States)

    2013-07-15

    Spectral red-shifting of high power laser pulses propagating through underdense plasma can be a source of ultrashort mid-infrared (MIR) radiation. During propagation, a high power laser pulse drives large amplitude plasma waves, depleting the pulse energy. At the same time, the large amplitude plasma wave provides a dynamic dielectric response that leads to spectral shifting. The loss of laser pulse energy and the approximate conservation of laser pulse action imply that spectral red-shifts accompany the depletion. In this paper, we investigate, through simulation, the parametric dependence of MIR generation on pulse energy, initial pulse duration, and plasma density.

  14. Regularized energy-dependent solar flare hard x-ray spectral index

    E-Print Network [OSTI]

    Eduard P. Kontar; Alexander L. MacKinnon

    2005-06-05

    The deduction from solar flare X-ray photon spectroscopic data of the energy dependent model-independent spectral index is considered as an inverse problem. Using the well developed regularization approach we analyze the energy dependency of spectral index for a high resolution energy spectrum provided by Ramaty High Energy Solar Spectroscopic Imager (RHESSI). The regularization technique produces much smoother derivatives while avoiding additional errors typical of finite differences. It is shown that observations imply a spectral index varying significantly with energy, in a way that also varies with time as the flare progresses. The implications of these findings are discussed in the solar flare context.

  15. Effluent monitoring Quality Assurance Project Plan for radioactive airborne emissions data. Revision 2

    SciTech Connect (OSTI)

    Frazier, T.P.

    1995-12-01

    This Quality Assurance Project Plan addresses the quality assurance requirements for compiling Hanford Site radioactive airborne emissions data. These data will be reported to the U.S. Environmental Protection Agency, the US Department of Energy, and the Washington State Department of Health. Effluent Monitoring performs compliance assessments on radioactive airborne sampling and monitoring systems. This Quality Assurance Project Plan is prepared in compliance with interim guidelines and specifications. Topics include: project description; project organization and management; quality assurance objectives; sampling procedures; sample custody; calibration procedures; analytical procedures; monitoring and reporting criteria; data reduction, verification, and reporting; internal quality control; performance and system audits; corrective actions; and quality assurance reports.

  16. Mon. Not. R. Astron. Soc. 000, 000--000 (0000) Printed 14 August 1997 (MN L A T E X style file v1.4) Spectral analysis of the high gravity extreme helium star

    E-Print Network [OSTI]

    :3; ffi 2000 = +06 21 46) was found to be hydrogen­deficient by Drilling during a spectroscopic survey of OB+ objects close to the Galactic plane (cf. Drilling 1980). The first high­resolution spectrum of LS that it was intermediate in effective temperature and surface gravity be­ tween the extreme helium stars (EHes) (Jeffery

  17. Energy Spectral Property in an Isolated CME-driven Shock

    E-Print Network [OSTI]

    Wang, Xin; Ding, Mingde; Wang, Na; Shan, Hao

    2015-01-01

    Observations from multiple spacecraft show that there are energy spectral "breaks" at 1-10MeV in some large CME-driven shocks. However, numerical models can hardly simulate this property due to high computational expense. The present paper focuses on analyzing these energy spectral "breaks" by Monte Carlo particle simulations of an isolated CME-driven shock. Taking the Dec 14 2006 CME-driven shock as an example, we investigate the formation of this energy spectral property. For this purpose, we apply different values for the scattering time in our isolated shock model to obtain the highest energy "tails", which can potentially exceed the "break" energy range. However, we have not found the highest energy "tails" beyond the "break" energy range, but instead find that the highest energy "tails" reach saturation near the range of energy at 5MeV. So, we believe that there exists an energy spectral "cut off" in an isolated shock. If there is no interaction with another shock, there would not be formation of the en...

  18. X-ray Spectral Properties of Gamma-Ray Bursts

    E-Print Network [OSTI]

    T. E. Strohmayer; E. E. Fenimore; T. Murakami; A. Yoshida

    1997-12-18

    We summarize the spectral characteristics of a sample of 22 bright gamma-ray bursts detected with the gamma-ray burst sensors aboard the satellite Ginga. This instrument employed a proportional and scintillation counter to provide sensitivity to photons in the 2 - 400 keV range, providing a unique opportunity to characterize the largely unexplored X-ray properties of gamma-ray bursts. The photon spectra of the Ginga bursts are well described by a low energy slope, a bend energy, and a high energy slope. In the energy range where they can be compared, this result is consistent with burst spectral analyses obtained from the BATSE experiment aboard the Compton Observatory. However, below 20 keV we find evidence for a positive spectral number index in approximately 40% of our burst sample, with some evidence for a strong rolloff at lower energies in a few events. There is a correlation (Pearson's r = -0.62) between the low energy slope and the bend energy. We find that the distribution of spectral bend energies extends below 10 keV. The observed ratio of energy emitted in the X-rays relative to the gamma-rays can be much larger than a few percent and, in fact, is sometimes larger than unity. The average for our sample is 24%.

  19. Source-dependent variation in hydroxyl radical production by airborne particulate matter

    SciTech Connect (OSTI)

    Marjan Alaghmand; Neil V. Blough [University of Maryland, College Park, MD (United States). Department of Chemistry and Biochemistry

    2007-04-01

    Epidemiological studies suggest exposure to airborne particles is responsible for a wide range of adverse health effects, potentially arising from particle-induced oxidative stress. A highly sensitive fluorescence method was employed to measure the production of hydroxyl radical by a broad range of particle types including urban dust, diesel particulate matter, coal fly ash, kaolinite, and silica. Little or no production of OH was observed in the absence of an added electron donor or H{sub 2}O{sub 2}. In the presence of a biological electron donor (NADPH, 3 mM), the rate of OH production (R{sub OH}) for 3 mg/mL of these particles varied from 23 nM s{sup -1} for diesel particulate matter (SRM 2975) to 0.20 nM s{sup -1} for coal fly ash (SRM 2689). No detectable OH was produced by kaolinite or silica. Hydroxyl radical formation was eliminated under anaerobic conditions and in the presence of catalase, indicating that O{sub 2} and H{sub 2}O{sub 2} are required for its generation. Partial inhibition of OH formation by superoxide dismutase (SOD) was also observed in some cases, suggesting that superoxide is also involved. The metal chelator deferoxamine mesylate (DFX) in most cases suppressed OH formation, but diethylenetriaminepentaacetic acid (DTPA) generally enhanced it, implicating metal ion reactions in OH generation as well. The dependence of R{sub OH} on NADPH concentration further implicates particle surface reactions in OH formation. To the authors' knowledge, these measurements provide the first quantitative estimate of ROH for a broad range of particle types. 49 refs., 6 figs., 1 tab.

  20. Spectral statistics for scaling quantum graphs

    E-Print Network [OSTI]

    Yu. Dabaghian

    2006-08-09

    The explicit solution to the spectral problem of quantum graphs is used to obtain the exact distributions of several spectral statistics, such as the oscillations of the quantum momentum eigenvalues around the average, $\\delta k_{n}=k_{n}-\\bar k_{n}$, and the nearest neighbor separations, $s_{n}=k_{n}-k_{n-1}$.

  1. The Airborne Aero-Optics Laboratory, AAOL Eric J. Jumpera1

    E-Print Network [OSTI]

    Gordeyev, Stanislav

    The Airborne Aero-Optics Laboratory, AAOL Eric J. Jumpera1 , Mike Zenka , Stanislav Gordeyeva Abstract This paper gives a background into aero-optics which is the effect that turbulent flow over discusses the magnitude of the detrimental effects that aero-optics has on optical system performance

  2. An Airborne Pod-mounted Dual Beam Interferometer Dragana Perkovic, Stephen J. Frasier, Russell Tessier

    E-Print Network [OSTI]

    Tessier, Russell

    of Massachusetts (UMass) to study ocean surface waves and currents in coastal regions. This airborne radar operates. Over several years, DBI was flown on a National Oceanic and Atmospheric Administration's WP-3D research aircraft in a number of successful missions collecting the data both over land and ocean. These deployments

  3. Flight Test Evaluation of a Prototype Optical Instrument for Airborne Sense-and-Avoid Applications

    E-Print Network [OSTI]

    Hornsey, Richard

    Flight Test Evaluation of a Prototype Optical Instrument for Airborne Sense-and-Avoid Applications sense-and-avoid instrument was constructed from low-cost commercial off-the- shelf components 205 and the Bell 206 (intruder aircraft) were fully instrumented to record position and orientation

  4. One-dimensional inversion of airborne electromagnetic data: application to oil sands exploration

    E-Print Network [OSTI]

    Farquharson, Colin G.

    One-dimensional inversion of airborne electromagnetic data: application to oil sands exploration, and Larry Mewhort. · Richard Kellett, formerly of Komex International. #12;Oil sands in Canada #12;Source: Mark Savage, "Oil Sands Characteristics - Geology," 9 April 2002 Wabasca Calgary Edmonton Cold Lake

  5. TOMOGRAPHIC RETRIEVAL OF CLOUD WATER DISTRIBUTIONS USING AN AIR-BORNE SCANNING MICROWAVE RADIOMETER

    E-Print Network [OSTI]

    TOMOGRAPHIC RETRIEVAL OF CLOUD WATER DISTRIBUTIONS USING AN AIR-BORNE SCANNING MICROWAVE RADIOMETER, for United States Government purposes. BNL-79834-2008-AB #12;ABSTRACT Microwave radiometers have been used, but neither the microwave technology nor the cloud models were mature enough for practical application

  6. Initial Attitude Estimation of Tactical Grade Inertial Measurement Unit for Airborne Environmental Camera

    E-Print Network [OSTI]

    Won, Chang-Hee

    1 Initial Attitude Estimation of Tactical Grade Inertial Measurement Unit for Airborne alignment depends on the inertial measurement unit's performance. In the case of the tactical grade inertial measurement unit, even though tilt angles can be estimated relatively accurately by using accelerometer

  7. DETECTION OF IMPULSE-LIKE AIRBORNE SOUND FOR DAMAGE IDENTIFICATION IN ROTOR BLADES OF WIND TURBINES

    E-Print Network [OSTI]

    Boyer, Edmond

    DETECTION OF IMPULSE-LIKE AIRBORNE SOUND FOR DAMAGE IDENTIFICATION IN ROTOR BLADES OF WIND TURBINES burdens of wind turbines. To detect damage of rotor blades, several research projects focus on an acoustic, rotor blade, wind turbine INTRODUCTION There are several publications of non destructive damage

  8. Statistical Issues in the Study of Air Pollution Involving Airborne Particulate Matter

    E-Print Network [OSTI]

    Washington at Seattle, University of

    Statistical Issues in the Study of Air Pollution Involving Airborne Particulate Matter Lawrence H which provides the Center's primary funding. #12;1 STATISTICAL ISSUES IN THE STUDY OF AIR POLLUTION.S. cities. This and other scientific and policy information formed the basis on which the U.S. Environmental

  9. Measurement of airborne radioactivity from the Fukushima reactor accident in Tokushima, Japan

    E-Print Network [OSTI]

    K. Fushimi; S. Nakayama; M. Sakama; Y. Sakaguchi

    2012-10-19

    The airborne radioactive isotopes from the Fukushima Daiichi nuclear plan t was measured in Tokushima, western Japan. The continuous monitoring has been carried out in Tokushima. From March 23, 2011 the fission product $^{131}$I was observed. The radioisotopes $^{134}$Cs and $^{137}$Cs were also observed in the beginning of April. However the densities were extremely smaller than the Japanese regulation of radioisotopes.

  10. Mali 2006/2007 Airborne Measurements (Mali 2006/2007 Mesures Aroportes)

    E-Print Network [OSTI]

    Delene, David J.

    Mali 2006/2007 Airborne Measurements (Mali 2006/2007 Mesures Aéroportées) #12;Measurement Objectives (Objectifs De Mesure) Determine if cloud seeding in Mali could be beneficial. (Déterminer si l'ensemencement des nuages au Mali pourrait être bénéfique.) Help determine what is the optimal seeding method

  11. Airborne thermal remote sensing for water temperature assessment in rivers and streams

    E-Print Network [OSTI]

    Brown, Sally

    ). Stream temperature monitoring presents challenges for water resource managers charged with the taskAirborne thermal remote sensing for water temperature assessment in rivers and streams Christian E are needed to assess spatial patterns of stream temperature at scales relevant to issues in water quality

  12. Computational Concerns in the Integration of Unmanned Airborne Systems into Controlled Airspace

    E-Print Network [OSTI]

    Johnson, Chris

    ], as well as EUROCONTROL's Spec-0102 on the Use of Military Unmanned Aerial Vehicles as Operational Air safeguards. Within the US military funding for Unmanned Airborne Vehicles (UAVs) development has increased London Olympics. A new generation of unmanned freight vehicles is being deployed to help the US military

  13. Apparatus and system for multivariate spectral analysis

    DOE Patents [OSTI]

    Keenan, Michael R. (Albuquerque, NM); Kotula, Paul G. (Albuquerque, NM)

    2003-06-24

    An apparatus and system for determining the properties of a sample from measured spectral data collected from the sample by performing a method of multivariate spectral analysis. The method can include: generating a two-dimensional matrix A containing measured spectral data; providing a weighted spectral data matrix D by performing a weighting operation on matrix A; factoring D into the product of two matrices, C and S.sup.T, by performing a constrained alternating least-squares analysis of D=CS.sup.T, where C is a concentration intensity matrix and S is a spectral shapes matrix; unweighting C and S by applying the inverse of the weighting used previously; and determining the properties of the sample by inspecting C and S. This method can be used by a spectrum analyzer to process X-ray spectral data generated by a spectral analysis system that can include a Scanning Electron Microscope (SEM) with an Energy Dispersive Detector and Pulse Height Analyzer.

  14. Augmented Classical Least Squares Multivariate Spectral Analysis

    DOE Patents [OSTI]

    Haaland, David M. (Albuquerque, NM); Melgaard, David K. (Albuquerque, NM)

    2005-01-11

    A method of multivariate spectral analysis, termed augmented classical least squares (ACLS), provides an improved CLS calibration model when unmodeled sources of spectral variation are contained in a calibration sample set. The ACLS methods use information derived from component or spectral residuals during the CLS calibration to provide an improved calibration-augmented CLS model. The ACLS methods are based on CLS so that they retain the qualitative benefits of CLS, yet they have the flexibility of PLS and other hybrid techniques in that they can define a prediction model even with unmodeled sources of spectral variation that are not explicitly included in the calibration model. The unmodeled sources of spectral variation may be unknown constituents, constituents with unknown concentrations, nonlinear responses, non-uniform and correlated errors, or other sources of spectral variation that are present in the calibration sample spectra. Also, since the various ACLS methods are based on CLS, they can incorporate the new prediction-augmented CLS (PACLS) method of updating the prediction model for new sources of spectral variation contained in the prediction sample set without having to return to the calibration process. The ACLS methods can also be applied to alternating least squares models. The ACLS methods can be applied to all types of multivariate data.

  15. Augmented Classical Least Squares Multivariate Spectral Analysis

    DOE Patents [OSTI]

    Haaland, David M. (Albuquerque, NM); Melgaard, David K. (Albuquerque, NM)

    2005-07-26

    A method of multivariate spectral analysis, termed augmented classical least squares (ACLS), provides an improved CLS calibration model when unmodeled sources of spectral variation are contained in a calibration sample set. The ACLS methods use information derived from component or spectral residuals during the CLS calibration to provide an improved calibration-augmented CLS model. The ACLS methods are based on CLS so that they retain the qualitative benefits of CLS, yet they have the flexibility of PLS and other hybrid techniques in that they can define a prediction model even with unmodeled sources of spectral variation that are not explicitly included in the calibration model. The unmodeled sources of spectral variation may be unknown constituents, constituents with unknown concentrations, nonlinear responses, non-uniform and correlated errors, or other sources of spectral variation that are present in the calibration sample spectra. Also, since the various ACLS methods are based on CLS, they can incorporate the new prediction-augmented CLS (PACLS) method of updating the prediction model for new sources of spectral variation contained in the prediction sample set without having to return to the calibration process. The ACLS methods can also be applied to alternating least squares models. The ACLS methods can be applied to all types of multivariate data.

  16. Augmented classical least squares multivariate spectral analysis

    DOE Patents [OSTI]

    Haaland, David M.; Melgaard, David K.

    2004-02-03

    A method of multivariate spectral analysis, termed augmented classical least squares (ACLS), provides an improved CLS calibration model when unmodeled sources of spectral variation are contained in a calibration sample set. The ACLS methods use information derived from component or spectral residuals during the CLS calibration to provide an improved calibration-augmented CLS model. The ACLS methods are based on CLS so that they retain the qualitative benefits of CLS, yet they have the flexibility of PLS and other hybrid techniques in that they can define a prediction model even with unmodeled sources of spectral variation that are not explicitly included in the calibration model. The unmodeled sources of spectral variation may be unknown constituents, constituents with unknown concentrations, nonlinear responses, non-uniform and correlated errors, or other sources of spectral variation that are present in the calibration sample spectra. Also, since the various ACLS methods are based on CLS, they can incorporate the new prediction-augmented CLS (PACLS) method of updating the prediction model for new sources of spectral variation contained in the prediction sample set without having to return to the calibration process. The ACLS methods can also be applied to alternating least squares models. The ACLS methods can be applied to all types of multivariate data.

  17. Warm absorbers in X-rays (WAX), a comprehensive high resolution grating spectral study of a sample of Seyfert galaxies: I. A global view and frequency of occurrence of warm absorbers

    E-Print Network [OSTI]

    Laha, Sibasish; Dewangan, Gulab C; Chakravorty, Susmita; Kembhavi, Ajit K

    2014-01-01

    We present results from a homogeneous analysis of the broadband 0.3-10 keV CCD resolution as well as of soft X-ray high-resolution grating spectra of a hard X-ray flux-limited sample of 26 Seyfert galaxies observed with XMM-Newton. Our goal is to characterise the warm absorber (WA) properties along the line-of-sight to the active nucleus. We significantly detect WAs in $65\\%$ of the sample sources. Our results are consistent with WAs being present in at least half of the Seyfert galaxies in the nearby Universe, in agreement with previous estimates . We find a gap in the distribution of the ionisation parameter in the range $0.5warm absorber flow is probably constituted by a clumpy distribution of discrete clouds rather than a continuous medium. The distribution of the WA column densities for the sources with broad Fe K$\\alpha$ lines are similar to those sources which do not have broadened emission l...

  18. Spectral Triples on Proper Etale Groupoids

    E-Print Network [OSTI]

    Antti J. Harju

    2014-12-15

    A proper etale Lie groupoid is modelled as a (noncommutative) spectral geometric space. The spectral triple is built on the algebra of smooth functions on the groupoid base which are invariant under the groupoid action. Stiefel-Whitney classes in Lie groupoid cohomology are introduced to measure the orientability of the tangent bundle and the obstruction to lift the tangent bundle to a spinor bundle. In the case of an orientable and spin Lie groupoid, an invariant spinor bundle and an invariant Dirac operator will be constructed. This data gives rise to a spectral triple. The algebraic orientability axiom in noncommutative geometry is reformulated to make it compatible with the geometric model.

  19. Method to analyze remotely sensed spectral data

    DOE Patents [OSTI]

    Stork, Christopher L. (Albuquerque, NM); Van Benthem, Mark H. (Middletown, DE)

    2009-02-17

    A fast and rigorous multivariate curve resolution (MCR) algorithm is applied to remotely sensed spectral data. The algorithm is applicable in the solar-reflective spectral region, comprising the visible to the shortwave infrared (ranging from approximately 0.4 to 2.5 .mu.m), midwave infrared, and thermal emission spectral region, comprising the thermal infrared (ranging from approximately 8 to 15 .mu.m). For example, employing minimal a priori knowledge, notably non-negativity constraints on the extracted endmember profiles and a constant abundance constraint for the atmospheric upwelling component, MCR can be used to successfully compensate thermal infrared hyperspectral images for atmospheric upwelling and, thereby, transmittance effects. Further, MCR can accurately estimate the relative spectral absorption coefficients and thermal contrast distribution of a gas plume component near the minimum detectable quantity.

  20. Online Spectral Clustering on Network Streams

    E-Print Network [OSTI]

    Jia, Yi

    2012-12-31

    Graph is an extremely useful representation of a wide variety of practical systems in data analysis. Recently, with the fast accumulation of stream data from various type of networks, significant research interests have arisen on spectral clustering...

  1. Efficient Spectral Methods for Transmission Eigenvalues and ...

    E-Print Network [OSTI]

    2014-03-24

    Mar 20, 2014 ... Efficient Spectral Methods for Transmission. Eigenvalues and Estimation of the Index of. Refraction. Jing An1,2,?, Jie Shen1,3. 1 School of ...

  2. arXiv:0801.2417v1[astro-ph]16Jan2008 RHESSI Spectral Fits of Swift GRBs

    E-Print Network [OSTI]

    California at Berkeley, University of

    The Reuven Ramaty High-Energy Solar Spectroscopic Imager (RHESSI) [1] is a dedi- cated solar observatory periodic modulation with the spin period. We perform spectral fitting in ISIS [4], a forward RHESSI counts for spectral analysis and produced acceptable joint fits. We selected analysis time

  3. XOP : a graphical user interface for spectral calculations and...

    Office of Scientific and Technical Information (OSTI)

    XOP : a graphical user interface for spectral calculations and x-ray optics utilities. Citation Details In-Document Search Title: XOP : a graphical user interface for spectral...

  4. Mass Correlation of Engine Emissions with Spectral Instruments...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Mass Correlation of Engine Emissions with Spectral Instruments Mass Correlation of Engine Emissions with Spectral Instruments 2004 Diesel Engine Emissions Reduction (DEER)...

  5. Webinar-Terrestrial Solar Spectral Modeling for Renewable Energy...

    Open Energy Info (EERE)

    Webinar-Terrestrial Solar Spectral Modeling for Renewable Energy: SMARTS Model Jump to: navigation, search Tool Summary Name: Webinar-Terrestrial Solar Spectral Modeling for...

  6. A fast-time study on increasing the capacity of continuous descent approaches through airborne precision spacing 

    E-Print Network [OSTI]

    Weitz, Lesley Anne

    2005-11-01

    Research Center (LaRC) in Hampton, Virginia, two parallel research efforts have focusedon terminal area research: one is Airborne Precision Spacing (APS), and the other is the Quiet Aircraft Technologies (QAT) project. The APS objective is to increase...

  7. Airborne and ground based measurements of volatile organic compounds using proton transfer reaction mass spectrometry in Texas and Mexico City 

    E-Print Network [OSTI]

    Fortner, Edward Charles

    2009-05-15

    Measurements of ambient volatile organic compounds (VOCs) by proton transfer reaction mass spectrometry (PTR-MS) are reported from recent airborne and surface based field campaigns. The Southeast Texas Tetroon Study (SETTS) ...

  8. Fuzzy logic approach to supervised segmentation of forest regions infested by Southern Pine Beetle using color airborne images 

    E-Print Network [OSTI]

    Ng, Kit-Tong

    1994-01-01

    Digital image processing technique and fuzzy logic approach are used to identify forest areas infested with Southern Pine Beetle, SPB, using normal color airborne imageries in this research. This research will be used as a front end of a larger...

  9. Method for the assessment of airborne off-target pesticide spray concentrations due to aircraft wing-tip vortex 

    E-Print Network [OSTI]

    Oliva, Sergio Eduardo

    2003-01-01

    The purpose of this thesis is to develop a method for assessing airborne concentrations caused by off-target pesticide drift. Concentrations are bounded by the worst credible circumstances within a normal aircraft pesticide spraying. It is assumed...

  10. An intercomparison of lidar-derived aerosol optical properties with airborne measurements near Tokyo during ACE-Asia

    E-Print Network [OSTI]

    Clarke, Antony

    and 6 km over Sagami Bay southwest of Tokyo. The C-130 observation package included a tracking Sun extinction coefficients (sa $ 0.03 kmÀ1 ) derived from the airborne tracking Sun photometer, in situ optical

  11. Multi-stage Robust Scheme for Citrus Identification from High Resolution Airborne Images

    E-Print Network [OSTI]

    Camps-Valls, Gustavo

    and the extensive information stored in a GIS database can also be used to aid in a visual or digital image accuracy demanded by institutions by means of combining automatic classification methods with visual/selection, pattern recognition, classification tree, support vector machine, neural networks. 1. INTRODUCTION Land

  12. Airborne radioactive material collection, measurement, and data storage for the Nuclear Science Center at Texas A&M University 

    E-Print Network [OSTI]

    Jones, Melody Louise

    1982-01-01

    AIRBORNE RADIOACTIVE MATERIAL COLLECTION, MEASUREMENT, AND DATA STORAGE FOR THE NUCLEAR SCIENCE CENTER AT TEXAS A&M UNIVERSITY A Thesis by MELODY LOUISE JONES Submitted to the Graduate College of Texas A&M University in partial fulfillment... of the requirement for the degree of MASTER OF SCIENCE August 1982 Major Subject: Nuclear Engineering AIRBORNE RADIOACTIVE MATERIAL COLLECTION& MEASUREMENT& AND DATA STORAGE FOR THE NUCLEAR SCIENCE CENTER AT TEXAS A&M UNIVERSITY A Thesis by MELODY LOUISE...

  13. Apparatus for real-time airborne particulate radionuclide collection and analysis

    DOE Patents [OSTI]

    Smart, John E. (West Richland, WA); Perkins, Richard W. (Richland, WA)

    2001-01-01

    An improved apparatus for collecting and analyzing an airborne particulate radionuclide having a filter mounted in a housing, the housing having an air inlet upstream of the filter and an air outlet downstream of the filter, wherein an air stream flows therethrough. The air inlet receives the air stream, the filter collects the airborne particulate radionuclide and permits a filtered air stream to pass through the air outlet. The improvement which permits real time counting is a gamma detecting germanium diode mounted downstream of the filter in the filtered air stream. The gamma detecting germanium diode is spaced apart from a downstream side of the filter a minimum distance for a substantially maximum counting detection while permitting substantially free air flow through the filter and uniform particulate radionuclide deposition on the filter.

  14. Solar spectral irradiance changes during cycle 24

    SciTech Connect (OSTI)

    Marchenko, S. V.; DeLand, M. T.

    2014-07-10

    We use solar spectra obtained by the Ozone Monitoring Instrument (OMI) on board the Aura satellite to detect and follow long-term (years) and short-term (weeks) changes in the solar spectral irradiance (SSI) in the 265-500 nm spectral range. During solar Cycle 24, in the relatively line-free regions the SSI changed by ?0.6% ± 0.2% around 265 nm. These changes gradually diminish to 0.15% ± 0.20% at 500 nm. All strong spectral lines and blends, with the notable exception of the upper Balmer lines, vary in unison with the solar 'continuum'. Besides the lines with strong chromospheric components, the most involved species include Fe I blends and all prominent CH, NH, and CN spectral bands. Following the general trend seen in the solar 'continuum', the variability of spectral lines also decreases toward longer wavelengths. The long-term solar cycle SSI changes are closely, to within the quoted 0.1%-0.2% uncertainties, matched by the appropriately adjusted short-term SSI variations derived from the 27 day rotational modulation cycles. This further strengthens and broadens the prevailing notion about the general scalability of the UV SSI variability to the emissivity changes in the Mg II 280 nm doublet on timescales from weeks to years. We also detect subtle deviations from this general rule: the prominent spectral lines and blends at ? ? 350 nm show slightly more pronounced 27 day SSI changes when compared to the long-term (years) trends. We merge the solar data from Cycle 21 with the current Cycle 24 OMI and GOME-2 observations and provide normalized SSI variations for the 170-795 nm spectral region.

  15. Device and method for accurately measuring concentrations of airborne transuranic isotopes

    DOE Patents [OSTI]

    McIsaac, C.V.; Killian, E.W.; Grafwallner, E.G.; Kynaston, R.L.; Johnson, L.O.; Randolph, P.D.

    1996-09-03

    An alpha continuous air monitor (CAM) with two silicon alpha detectors and three sample collection filters is described. This alpha CAM design provides continuous sampling and also measures the cumulative transuranic (TRU), i.e., plutonium and americium, activity on the filter, and thus provides a more accurate measurement of airborne TRU concentrations than can be accomplished using a single fixed sample collection filter and a single silicon alpha detector. 7 figs.

  16. Device and method for accurately measuring concentrations of airborne transuranic isotopes

    DOE Patents [OSTI]

    McIsaac, Charles V. (Idaho Falls, ID); Killian, E. Wayne (Idaho Falls, ID); Grafwallner, Ervin G. (Arco, ID); Kynaston, Ronnie L. (Blackfoot, ID); Johnson, Larry O. (Pocatello, ID); Randolph, Peter D. (Idaho Falls, ID)

    1996-01-01

    An alpha continuous air monitor (CAM) with two silicon alpha detectors and three sample collection filters is described. This alpha CAM design provides continuous sampling and also measures the cumulative transuranic (TRU), i.e., plutonium and americium, activity on the filter, and thus provides a more accurate measurement of airborne TRU concentrations than can be accomplished using a single fixed sample collection filter and a single silicon alpha detector.

  17. Geophex Airborne Unmanned Survey System (GAUSS). Topical report, October 1993--March 1995

    SciTech Connect (OSTI)

    1995-03-01

    The objectives of the project are to construct a geophysical sensor system based on a remotely operated model helicopter (ROH) and to evaluate the efficacy of the system for characterization of hazardous environmental sites. Geophex Airborne Unmanned Survey System (GAUSS) is a geophysical survey system that uses a ROH as the survey vehicle. We have selected the ROH because of its advantages over fixed wing and ground based vehicles. Lower air speed and superior maneuverability of the ROH make it better suited for geophysical surveys than a fixed wing model aircraft. The ROH can fly close to the ground, allowing detection of weak or subtle anomalies. Unlike ground based vehicles, the ROH can traverse difficult terrain while providing a stable sensor platform. ROH does not touch the ground during the course of a survey and is capable of functioning over water and surf zones. The ROH has been successfully used in the motion picture industry and by geology companies for payload bearing applications. The only constraint to use of the airborne system is that the ROH must remain visible to the pilot. Obstructed areas within a site can be characterized by relocating the base station to alternate positions. GAUSS consists of a ROH with radio controller, a data acquisition and processing (DAP) system, and lightweight digital sensor systems. The objective of our Phase I research was to develop a DAP and sensors suitable for ROH operation. We have constructed these subsystems and integrated them to produce an automated, hand-held geophysical surveying system, referred to as the ``pre-prototype``. We have performed test surveys with the pre-prototype to determine the functionality of the and DAP and sensor subsystems and their suitability for airborne application. The objective of the Phase II effort will be to modify the existing subsystems and integrate them into an airborne prototype. Efficacy of the prototype for geophysical survey of hazardous sites will then be determined.

  18. High-spectral-resolutionfluorescence light detection and rangingfor mesospheric sodium

    E-Print Network [OSTI]

    of the laser output can be monitored simultaneously during data acquisition with Doppler,Tehran, Iran. Received 12 October 1990. 0003-6935/92/122095-12$05.00/0. o 1992 Optical Society of America

  19. Optical Modulation and Detection Techniques for High-Spectral Efficiency

    E-Print Network [OSTI]

    Chien, Cheng-Chung

    2008-01-01

    an x optical spectrum analyzer with ~ 10 pm resolution. Fig.Agilent 86146B optical spectrum analyzer (OSA), operated inusing an optical spectrum analyzer with ~ 10 pm resolution.

  20. Spectral and High-Order Methods with Applications

    E-Print Network [OSTI]

    2006-08-28

    Suppose that our objective is to compute. P ...... plicated internal transition regions. ...... the energy contribution from the modes vik for i = 0,··· ,M ? N + k and vk,j.

  1. Cloud properties derived from the High Spectral Resolution Lidar during

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 OutreachProductswsicloudwsiclouddenDVA N C E D BGene NetworkNuclearDNP 20082 P r o j eCommittee offromandMPACE

  2. Gamma-analysis of airborne particulates sampled in Youzhno-Sakhalinsk town at March - April 2011

    E-Print Network [OSTI]

    Tertyshnik, E G; Andreev, F A; Artemyev, G B

    2012-01-01

    The experience of discovery of the radioactive products which have released into atmosphere of Sakhalin region from Fukushima Daiichi accident is presented. Sampling of airborne particulates and atmosphere fallout was carried out by means of the air ventilation set and horizontal gauze planchs, respectively. The HPGe detector was used for gamma analyses of the airborne samples. Since 23 March we confidently measured 131I in the airborne samples, after 03.04.2011 we also registered a rise of activity 137Cs and 134Cs. 132Te and 132I were discovered in ashen sample of the planch, which had exposed in Youzhno-Kurilk from 14 to 17 March. The effect of the pairs production when in the samples 208Tl presence, which emits gamma-quanta of 2615 keV, causes a rise in apparatus spectra of the peak corresponding to energy 1593 keV, which could be in error ascribed to 140La. It had been experimentally shown that the systematic reduction of 134Cs content in measuring samples due to effect of gamma - gamma coincidence did no...

  3. Gamma-analysis of airborne particulates sampled in Youzhno-Sakhalinsk town at March - April 2011

    E-Print Network [OSTI]

    E. G. Tertyshnik; V. P. Martynenko; F. A. Andreev; G. B. Artemyev

    2012-03-22

    The experience of discovery of the radioactive products which have released into atmosphere of Sakhalin region from Fukushima Daiichi accident is presented. Sampling of airborne particulates and atmosphere fallout was carried out by means of the air ventilation set and horizontal gauze planchs, respectively. The HPGe detector was used for gamma analyses of the airborne samples. Since 23 March we confidently measured 131I in the airborne samples, after 03.04.2011 we also registered a rise of activity 137Cs and 134Cs. 132Te and 132I were discovered in ashen sample of the planch, which had exposed in Youzhno-Kurilk from 14 to 17 March. The effect of the pairs production when in the samples 208Tl presence, which emits gamma-quanta of 2615 keV, causes a rise in apparatus spectra of the peak corresponding to energy 1593 keV, which could be in error ascribed to 140La. It had been experimentally shown that the systematic reduction of 134Cs content in measuring samples due to effect of gamma - gamma coincidence did not exceed 7 % (for the detector and geometry of the measurement used).

  4. AIRBORNE, OPTICAL REMOTE SENSING OF METHANE AND ETHANE FOR NATURAL GAS PIPELINE LEAK DETECTION

    SciTech Connect (OSTI)

    Jerry Myers

    2003-11-12

    Ophir Corporation was awarded a contract by the U. S. Department of Energy, National Energy Technology Laboratory under the Project Title ''Airborne, Optical Remote Sensing of Methane and Ethane for Natural Gas Pipeline Leak Detection'' on October 14, 2002. This second six-month technical report summarizes the progress made towards defining, designing, and developing the hardware and software segments of the airborne, optical remote methane and ethane sensor. The most challenging task to date has been to identify a vendor capable of designing and developing a light source with the appropriate output wavelength and power. This report will document the work that has been done to identify design requirements, and potential vendors for the light source. Significant progress has also been made in characterizing the amount of light return available from a remote target at various distances from the light source. A great deal of time has been spent conducting laboratory and long-optical path target reflectance measurements. This is important since it helps to establish the overall optical output requirements for the sensor. It also reduces the relative uncertainty and risk associated with developing a custom light source. The data gathered from the optical path testing has been translated to the airborne transceiver design in such areas as: fiber coupling, optical detector selection, gas filters, and software analysis. Ophir will next, summarize the design progress of the transceiver hardware and software development. Finally, Ophir will discuss remaining project issues that may impact the success of the project.

  5. Noise power spectral density of a fibre scattered-light interferometer with a semiconductor laser source

    SciTech Connect (OSTI)

    Alekseev, A E; Potapov, V T

    2013-10-31

    Spectral characteristics of the noise intensity fluctuations at the output of a scattered-light interferometer, caused by phase fluctuations of semiconductor laser radiation are considered. This kind of noise is one of the main factors limiting sensitivity of interferometric sensors. For the first time, to our knowledge, the expression is obtained for the average noise power spectral density at the interferometer output versus the degree of a light source coherence and length of the scattering segment. Also, the approximate expressions are considered which determine the power spectral density in the low-frequency range (up to 200 kHz) and in the limiting case of extended scattering segments. The expression obtained for the noise power spectral density agrees with experimental normalised power spectra with a high accuracy. (interferometry of radiation)

  6. Facility for spectral irradiance and radiance responsivity calibrations using uniform sources

    SciTech Connect (OSTI)

    Brown, Steven W.; Eppeldauer, George P.; Lykke, Keith R

    2006-11-10

    Detectors have historically been calibrated for spectral power responsivity at the National Institute of Standards and Technology by using a lamp-monochromator system to tune the wavelength of the excitation source. Silicon detectors can be calibrated in the visible spectral region with combined standard uncertainties at the 0.1% level. However,uncertainties increase dramatically when measuring an instrument's spectral irradiance or radiance responsivity. We describe what we believe to be a new laser-based facility for spectral irradiance and radiance responsivity calibrations using uniform sources (SIRCUS) that was developed to calibrate instruments directly in irradiance or radiance mode with uncertainties approaching or exceeding those available for spectral power responsivity calibrations. In SIRCUS, the emission from high-power, tunable lasers is introduced into an integrating sphere using optical fibers, producing uniform, quasi-Lambertian, high-radiant-flux sources. Reference standard irradiance detectors, calibrated directly against national primary standards for spectral power responsivity and aperture area measurement,are used to determine the irradiance at a reference plane. Knowing the measurement geometry, the source radiance can be readily determined as well. The radiometric properties of the SIRCUS source coupled with state-of-the-art transfer standard radiometers whose responsivities are directly traceable to primary national radiometric scales result in typical combined standard uncertainties in irradiance and radiance responsivity calibrations of less than 0.1%. The details of the facility and its effect on primary national radiometric scales are discussed.

  7. New H-band Stellar Spectral Libraries for the SDSS-III/APOGEE survey

    E-Print Network [OSTI]

    Zamora, O; Prieto, C Allende; Carrera, R; Koesterke, L; Edvardsson, B; Castelli, F; Plez, B; Bizyaev, D; Cunha, K; Perez, A E Garcia; Gustafsson, B; Holtzman, J A; Lawler, J E; Majewski, S R; Manchado, A; Meszaros, Sz; Shane, N; Shetrone, M; Smith, V V; Zasowski, G

    2015-01-01

    The Sloan Digital Sky Survey--III (SDSS--III) Apache Point Observatory Galactic Evolution Experiment (APOGEE) has obtained high resolution (R $\\sim$ 22,500), high signal-to-noise ($>$ 100) spectra in the H$-$band spectral region ($\\sim$1.5$-$1.7 $\\mu$m) for about 146,000 stars in the Milky Way galaxy. We have computed specific spectral libraries with effective temperature ($T\\rm{_{eff}}$) ranging from 3500 to 8000 K for the automated chemical analysis of the survey data. The spectral libraries, used to derive stellar parameters and abundances from the APOGEE spectra in the SDSS--III data release 12 (DR12), are based on ATLAS9 model atmospheres and the ASS$\\epsilon$T spectral synthesis code. We present a second set of stellar spectral libraries based on MARCS model atmospheres and the spectral synthesis code Turbospectrum. The ATLAS9/ASS$\\epsilon$T ($T\\rm{_{eff}}$ = 3500$-$8000 K) and MARCS/Turbospectrum ($T\\rm{_{eff}}$ = 3500$-$5500 K) grids of synthetic spectra cover a wide range of metallicity ($-$2.5 $\\leq...

  8. Information-efficient spectral imaging sensor

    DOE Patents [OSTI]

    Sweatt, William C. (Albuquerque, NM); Gentry, Stephen M. (Albuquerque, NM); Boye, Clinton A. (Albuquerque, NM); Grotbeck, Carter L. (Albuquerque, NM); Stallard, Brian R. (Albuquerque, NM); Descour, Michael R. (Tucson, AZ)

    2003-01-01

    A programmable optical filter for use in multispectral and hyperspectral imaging. The filter splits the light collected by an optical telescope into two channels for each of the pixels in a row in a scanned image, one channel to handle the positive elements of a spectral basis filter and one for the negative elements of the spectral basis filter. Each channel for each pixel disperses its light into n spectral bins, with the light in each bin being attenuated in accordance with the value of the associated positive or negative element of the spectral basis vector. The spectral basis vector is constructed so that its positive elements emphasize the presence of a target and its negative elements emphasize the presence of the constituents of the background of the imaged scene. The attenuated light in the channels is re-imaged onto separate detectors for each pixel and then the signals from the detectors are combined to give an indication of the presence or not of the target in each pixel of the scanned scene. This system provides for a very efficient optical determination of the presence of the target, as opposed to the very data intensive data manipulations that are required in conventional hyperspectral imaging systems.

  9. Infrared spectral properties of M giants

    E-Print Network [OSTI]

    Sloan, G C; Ramirez, R M; Kraemer, K E; Engelke, C W

    2015-01-01

    We observed a sample of 20 M giants with the Infrared Spectrograph on the Spitzer Space Telescope. Most show absorption structure at 6.6-6.8 um which we identify as water vapor, and in some cases, the absorption extends from 6.4 um into the SiO band at 7.5 um. Variable stars show stronger H2O absorption. While the strength of the SiO fundamental at 8 um increases monotonically from spectral class K0 to K5, the dependence on spectral class weakens in the M giants. As with previously studied samples, the M giants show considerable scatter in SiO band strength within a given spectral class. All of the stars in our sample also show OH band absorption, most noticeably in the 14-17 um region. The OH bands behave much like the SiO bands, increasing in strength in the K giants but showing weaker dependence on spectral class in the M giants, and with considerable scatter. An examination of the photometric properties reveals that the V-K color may be a better indicator of molecular band strength than the spectral class...

  10. Evaluation of airborne geophysical surveys for large-scale mapping of contaminated mine pools: draft final report

    SciTech Connect (OSTI)

    Geosciences Division, National Energy Technology Laboratory, US Department of Energy, Pittsburgh, PA; Hammack, R.W.

    2006-12-28

    Decades of underground coal mining has left about 5,000 square miles of abandoned mine workings that are rapidly filling with water. The water quality of mine pools is often poor; environmental regulatory agencies are concerned because water from mine pools could contaminate diminishing surface and groundwater supplies. Mine pools are also a threat to the safety of current mining operations. Conversely, mine pools are a large, untapped water resource that, with treatment, could be used for a variety of industrial purposes. Others have proposed using mine pools in conjunction with heat pumps as a source of heating and cooling for large industrial facilities. The management or use of mine pool water requires accurate maps of mine pools. West Virginia University has predicted the likely location and volume of mine pools in the Pittsburgh Coalbed using existing mine maps, structure contour maps, and measured mine pool elevations. Unfortunately, mine maps only reflect conditions at the time of mining, are not available for all mines, and do not always denote the maximum extent of mining. Since 1999, the National Energy Technology Laboratory (NETL) has been evaluating helicopter-borne, electromagnetic sensing technologies for the detection and mapping of mine pools. Frequency domain electromagnetic sensors are able to detect shallow mine pools (depth < 50 m) if there is sufficient contrast between the conductance of the mine pool and the conductance of the overburden. The mine pools (conductors) most confidently detected by this technology are overlain by thick, resistive sandstone layers. In 2003, a helicopter time domain electromagnetic sensor was applied to mined areas in southwestern Virginia in an attempt to increase the depth of mine pool detection. This study failed because the mine pool targets were thin and not very conductive. Also, large areas of the surveys were degraded or made unusable by excessive amounts of cultural electromagnetic noise that obscured the subtle mine pool anomalies. However, post-survey modeling suggested that thicker, more conductive mine pools might be detected at a more suitable location. The current study sought to identify the best time domain electromagnetic sensor for detecting mine pools and to test it in an area where the mine pools are thicker and more conductive that those in southwestern Virginia. After a careful comparison of all airborne time domain electromagnetic sensors (including both helicopter and fixed-wing systems), the SkyTEM system from Denmark was determined to be the best technology for this application. Whereas most airborne time domain electromagnetic systems were developed to find large, deep, highly conductive mineral deposits, the SkyTEM system is designed for groundwater exploration studies, an application similar to mine pool detection.

  11. Fast spectral source integration in black hole perturbation calculations

    E-Print Network [OSTI]

    Seth Hopper; Erik Forseth; Thomas Osburn; Charles R. Evans

    2015-06-15

    This paper presents a new technique for achieving spectral accuracy and fast computational performance in a class of black hole perturbation and gravitational self-force calculations involving extreme mass ratios and generic orbits. Called \\emph{spectral source integration} (SSI), this method should see widespread future use in problems that entail (i) point-particle description of the small compact object, (ii) frequency domain decomposition, and (iii) use of the background eccentric geodesic motion. Frequency domain approaches are widely used in both perturbation theory flux-balance calculations and in local gravitational self-force calculations. Recent self-force calculations in Lorenz gauge, using the frequency domain and method of extended homogeneous solutions, have been able to accurately reach eccentricities as high as $e \\simeq 0.7$. We show here SSI successfully applied to Lorenz gauge. In a double precision Lorenz gauge code, SSI enhances the accuracy of results and makes a factor of three improvement in the overall speed. The primary initial application of SSI--for us its \\emph{raison d'\\^{e}tre}--is in an arbitrary precision \\emph{Mathematica} code that computes perturbations of eccentric orbits in the Regge-Wheeler gauge to extraordinarily high accuracy (e.g., 200 decimal places). These high accuracy eccentric orbit calculations would not be possible without the exponential convergence of SSI. We believe the method will extend to work for inspirals on Kerr, and will be the subject of a later publication. SSI borrows concepts from discrete-time signal processing and is used to calculate the mode normalization coefficients in perturbation theory via sums over modest numbers of points around an orbit. A variant of the idea is used to obtain spectral accuracy in solution of the geodesic orbital motion.

  12. Airborne coastal current survey system for difficult to access areas 

    E-Print Network [OSTI]

    Pollock, Cheryl Elaine

    1994-01-01

    . Because the meter is not deployed at a stationary location, the use of only one current meter is required, and insitu deployment problems with scour or burying are alleviated. To demonstrate the capabilities of the system, data obtained under high-energy...

  13. Classical least squares multivariate spectral analysis

    DOE Patents [OSTI]

    Haaland, David M. (Albuquerque, NM)

    2002-01-01

    An improved classical least squares multivariate spectral analysis method that adds spectral shapes describing non-calibrated components and system effects (other than baseline corrections) present in the analyzed mixture to the prediction phase of the method. These improvements decrease or eliminate many of the restrictions to the CLS-type methods and greatly extend their capabilities, accuracy, and precision. One new application of PACLS includes the ability to accurately predict unknown sample concentrations when new unmodeled spectral components are present in the unknown samples. Other applications of PACLS include the incorporation of spectrometer drift into the quantitative multivariate model and the maintenance of a calibration on a drifting spectrometer. Finally, the ability of PACLS to transfer a multivariate model between spectrometers is demonstrated.

  14. Investigating the Spectral Anomaly with Different Reactor Antineutrino Experiments

    E-Print Network [OSTI]

    Christian Buck; Antoine P. Collin; Julia Haser; Manfred Lindner

    2015-12-21

    The spectral shape of reactor antineutrinos measured in recent experiments shows anomalies in the neutrino flux predictions. New precision measurements of the reactor neutrino spectra as well as more complete input in nuclear data bases are needed to resolve the observed discrepancies between flux models and experimental results. We combine experiments at reactors which are highly enriched in ${}^{235}$U with commercial reactors with typically lower enrichment to gain new insights into the origin of the anomalous neutrino spectrum. As an example, we discuss the option of a direct comparison of the measured shape in the currently running Double Chooz near detector and the upcoming Stereo experiment.

  15. Representations of spectral coordinates in FITS

    E-Print Network [OSTI]

    E. W. Greisen; M. R. Calabretta; F. G. Valdes; S. L. Allen

    2005-10-07

    Greisen & Calabretta describe a generalized method for specifying the coordinates of FITS data samples. Following that general method, Calabretta & Greisen describe detailed conventions for defining celestial coordinates as they are projected onto a two-dimensional plane. The present paper extends the discussion to the spectral coordinates of wavelength, frequency, and velocity. World coordinate functions are defined for spectral axes sampled linearly in wavelength, frequency, or velocity, linearly in the logarithm of wavelength or frequency, as projected by ideal dispersing elements, and as specified by a lookup table.

  16. Spectral properties of magnetic chain graphs

    E-Print Network [OSTI]

    Pavel Exner; Stepan Manko

    2015-07-02

    We discuss spectral properties of a charged quantum particle confined to a chain graph consisting of an infinite array of rings under influence of a magnetic field assuming a $\\delta$-coupling at the points where the rings touch. We start with the situation when the system has a translational symmetry and analyze spectral consequences of perturbations of various kind, such as a local change of the magnetic field, of the coupling constant, or of a ring circumference. A particular attention is paid to weak perturbations, both local and periodic; for the latter we prove a version of Saxon-Hutner conjecture.

  17. Inflation models, spectral index and observational constraints

    E-Print Network [OSTI]

    Laura Covi

    2000-03-30

    We have evaluated the observational constraints on the spectral index $n$, in the context of a $\\Lambda$CDM model. For $n$ scale-independent, as predicted by most models of inflation, present data require $n\\simeq 1.0 \\pm 0.1$ at the 2-$\\sigma$ level. We have also studied the two-parameter scale-dependent spectral index, predicted by running-mass inflation models. Present data allow significant variation of $n$ in this case, within the theoretically preferred region of parameter space.

  18. Multi Spectral Pushbroom Imaging Radiometer (MPIR) for remote sensing cloud studies

    SciTech Connect (OSTI)

    Phipps, G.S.; Grotbeck, C.L.

    1995-10-01

    A Multi Spectral Pushbroom Imaging Radiometer (MPIR) has been developed as are relatively inexpensive ({approximately}$IM/copy), well-calibrated,imaging radiometer for aircraft studies of cloud properties. The instrument is designed to fly on an Unmanned Aerospace Vehicle (UAV) platform at altitudes from the surface up to 20 km. MPIR is being developed to support the Unmanned Aerospace Vehicle portion of the Department of Energy`s Atmospheric Radiation Measurements program (ARM/UAV). Radiation-cloud interactions are the dominant uncertainty in the current General Circulation Models used for atmospheric climate studies. Reduction of this uncertainty is a top scientific priority of the US Global Change Research Program and the ARM program. While the DOE`s ARM program measures a num-ber of parameters from the ground-based Clouds and Radiation Testbed sites, it was recognized from the outset that other key parameters are best measured by sustained airborne data taking. These measurements are critical in our understanding of global change issues as well as for improved atmospheric and near space weather forecasting applications.

  19. Soft X-ray spectral variability of AM Herculis

    E-Print Network [OSTI]

    K. Beuermann; E. El Kholy; K. Reinsch

    2008-02-19

    Polars (AM Herculis binaries) are a prominent class of bright soft X-ray sources, many of which were discovered with ROSAT. We present a homogenous analysis of all the pointed ROSAT PSPC observations of polars subdivided into two papers that discuss the prototype polar AM Her in detail and summarize the class properties of all other polars. We derive the high-state soft X-ray flux and short-term spectral variability of AM Her using a new detector response matrix and a confirmed flux calibration of the ROSAT PSPC below 0.28 keV. The best-fit mean single-blackbody temperature and integrated bright-phase energy flux of AM Her in its April 1991 high state are 27.2 +/- 1.0 eV and (2.6 +/- 0.6) x 10^-9 erg cm^-2s^-1, respectively. The total blackbody flux of a multi-temperature model that fits both the soft X-ray and the fluctuating far-ultraviolet components is Fbb = (4.5 +/- 1.5) x 10^-9 erg cm^-2s^-1. The total accretion luminosity at a distance of 80 pc, Lbb = (2.1 +/- 0.7) x 10^33 erg s-1, implies an accretion rate of Mdot = (2.4 +/- 0.8) x 10^-10 Msun yr^-1 for an 0.78 Msun white dwarf. The soft X-ray flux displays significant variability on time scales down to 200 ms. Correlated spectral and count-rate variations are seen in flares on time scales down to 1 s, demonstrating the heating and cooling associated with individual accretion events. Our spectral and temporal analysis provides direct evidence for the blobby accretion model and suggests a connection between the soft X-ray and the fluctuating far-ultraviolet components.

  20. The Effect of Magnetic Turbulence Energy Spectral

    E-Print Network [OSTI]

    Ng, Chung-Sang

    The Effect of Magnetic Turbulence Energy Spectral Scaling on the Heating of the Solar Wind C. S. Ng), Kraichnan (1965) #12;Solar wind turbulence model The steady state solar wind turbulence model developed wind with uniform speed Vsw 1D (radial position r) Turbulence characterized by two fields

  1. Spectral Image Utility Prediction Marcus S. Stefanou

    E-Print Network [OSTI]

    Kerekes, John

    using the constrained energy minimization matched filter detector. The result of our initial work-distributions. The target models come from a library of target materials and are assumed to be multivariate Gaussian longer term objective is to build on this initial result by developing a more general spectral image

  2. Spectral Hardening of Large Solar Flares

    E-Print Network [OSTI]

    Paolo C. Grigis; Arnold O. Benz

    2008-05-01

    RHESSI observations are used to quantitatively study the hard X-ray evolution in 5 large solar flares selected for spectral hardening in the course of the event. The X-ray bremsstrahlung emission from non-thermal electrons is characterized by two spectroscopically distinct phases: impulsive and gradual. The impulsive phase usually consists of several emission spikes following a soft-hard-soft spectral pattern, whereas the gradual stage manifests itself as spectral hardening while the flux slowly decreases. Both the soft-hard-soft (impulsive) phase and the hardening (gradual) phase are well described by piecewise linear dependence of the photon spectral index on the logarithm of the hard X-ray flux. The different linear parts of this relation correspond to different rise and decay phases of emission spikes. The temporal evolution of the spectra is compared with the configuration and motion of the hard X-ray sources in RHESSI images. These observations reveal that the two stages of electron acceleration causing these two different behaviors are closely related in space and time. The transition between the impulsive and gradual phase is found to be smooth and progressive rather than abrupt. This suggests that they arise because of a slow change in a common accelerator rather than being caused by two independent and distinct acceleration processes. We propose that the hardening during the decay phase is caused by continuing particle acceleration with longer trapping in the accelerator before escape.

  3. A Stabilised Nodal Spectral Element Method for Fully Nonlinear Water Waves

    E-Print Network [OSTI]

    Engsig-Karup, Allan Peter; Bigoni, Daniele

    2015-01-01

    We present an arbitrary-order spectral element method for general-purpose simulation of non-overturning water waves, described by fully nonlinear potential theory. The method can be viewed as a high-order extension of the classical finite element method proposed by Cai et al (1998) \\cite{CaiEtAl1998}, although the numerical implementation differs greatly. Features of the proposed spectral element method include: nodal Lagrange basis functions, a general quadrature-free approach and gradient recovery using global $L^2$ projections. The quartic nonlinear terms present in the Zakharov form of the free surface conditions can cause severe aliasing problems and consequently numerical instability for marginally resolved or very steep waves. We show how the scheme can be stabilised through a combination of over-integration of the Galerkin projections and a mild spectral filtering on a per element basis. This effectively removes any aliasing driven instabilities while retaining the high-order accuracy of the numerical...

  4. Hard X-Ray Imaging of Individual Spectral Components in Solar Flares

    E-Print Network [OSTI]

    Caspi, Amir; McTiernan, James M; Krucker, Säm

    2015-01-01

    We present a new analytical technique, combining Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) high-resolution imaging and spectroscopic observations, to visualize solar flare emission as a function of spectral component (e.g., isothermal temperature) rather than energy. This computationally inexpensive technique is applicable to all spatially-invariant spectral forms and is useful for visualizing spectroscopically-determined individual sources and placing them in context, e.g., comparing multiple isothermal sources with nonthermal emission locations. For example, while extreme ultraviolet images can usually be closely identified with narrow temperature ranges, due to the emission being primarily from spectral lines of specific ion species, X-ray images are dominated by continuum emission and therefore have a broad temperature response, making it difficult to identify sources of specific temperatures regardless of the energy band of the image. We combine RHESSI calibrated X-ray visibilities wi...

  5. Direct probe of spectral inhomogeneity reveals synthetic tunability of single-nanocrystal spectral linewidths

    E-Print Network [OSTI]

    Cui, Jian

    The spectral linewidth of an ensemble of fluorescent emitters is dictated by the combination of single-emitter linewidths and sample inhomogeneity. For semiconductor nanocrystals, efforts to tune ensemble linewidths for ...

  6. AIRBORNE, OPTICAL REMOTE SENSING OF METHANE AND ETHANE FOR NATURAL GAS PIPELINE LEAK DETECTION

    SciTech Connect (OSTI)

    Jerry Myers

    2003-05-13

    Ophir Corporation was awarded a contract by the U. S. Department of Energy, National Energy Technology Laboratory under the Project Title ''Airborne, Optical Remote Sensing of Methane and Ethane for Natural Gas Pipeline Leak Detection'' on October 14, 2002. This six-month technical report summarizes the progress for each of the proposed tasks, discusses project concerns, and outlines near-term goals. Ophir has completed a data survey of two major natural gas pipeline companies on the design requirements for an airborne, optical remote sensor. The results of this survey are disclosed in this report. A substantial amount of time was spent on modeling the expected optical signal at the receiver at different absorption wavelengths, and determining the impact of noise sources such as solar background, signal shot noise, and electronic noise on methane and ethane gas detection. Based upon the signal to noise modeling and industry input, Ophir finalized the design requirements for the airborne sensor, and released the critical sensor light source design requirements to qualified vendors. Responses from the vendors indicated that the light source was not commercially available, and will require a research and development effort to produce. Three vendors have responded positively with proposed design solutions. Ophir has decided to conduct short path optical laboratory experiments to verify the existence of methane and absorption at the specified wavelength, prior to proceeding with the light source selection. Techniques to eliminate common mode noise were also evaluated during the laboratory tests. Finally, Ophir has included a summary of the potential concerns for project success and has established future goals.

  7. Solubility Classification of Airborne Uranium Products from LWR-Fuel Plants

    SciTech Connect (OSTI)

    kalkwarf, D. R.

    1980-08-01

    Airborne dust samples were obtained from various locations within plants manufacturing fuel elements for light-water reactors, and the dissolution rates of uranium from these samples into simulated lung fluid at 37°C were measured. These measurements were used to classify the solubilities of the samples in terms of the lung clearance model proposed by the International Commission on Radiological Protection. Similar evaluations were performed for samples of pure uranium compounds expected as components in plant dust. The variation in solubility classifications of dust encountered along the fuel production lines is described and correlated with the process chemistry and the solubility classifications of the pure uranium compounds.

  8. ARM Airborne Carbon Measurements VI (ARM-ACME V) Science Plan

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room News Publications Traditional Knowledge Kiosks Barrow, Alaska TropicalStorms7 ARM Airborne

  9. Airborne concentrations of asbestos in 71 school buildings

    SciTech Connect (OSTI)

    Corn, M.; Crump, K.; Farrar, D.B.; Lee, R.J.; McFee, D.R. (Johns Hopkins Univ., Baltimore, MD (USA))

    1991-02-01

    A total of 473 air samples from 71 schools scheduled for abatement (328 indoor static samples, 51 personal samples, and 94 outdoor samples) were analyzed by transmission electron microscopy techniques. Six measures of asbestos-in-air concentration were considered: (1) total asbestos structures per cubic centimeter: (2) chrysotile structures per cubic centimeter; (3) amphibole structures per cubic centimeter; (4) structures per cubic centimeter at least 0.5 micron long and at least five times wide; (5) structures per cubic centimeter at least 5 microns long; and (6) structures per cubic centimeter at least 5 microns long and at least 0.2 micron wide. The average concentration of chrysotile structures in indoor air samples was 0.017 structures/cm{sup 3}; the average concentration of amphibole structures was 0.0015 structure/cm{sup 3}. Ninety-five percent of structures found were chrysotile. The average concentrations of all structures were significantly higher indoors than outdoors (P less than 0.001). The average concentration of structures more than 5 microns long indoors was 0.00023 structure/cm{sup 3}. None of the following factors were significantly correlated with asbestos concentrations in air: type of asbestos-containing materials (ACM) present, condition of ACM, accessibility of ACM to students, whether ACM were covered, air flow, or whether sweeping was noted during sample collection. In addition, asbestos-in-air concentrations were not significantly different in different types of schools (high, intermediate or elementary) or in schools constructed in different time periods. Lastly, there was no correlation between the mineral type of asbestos found in the air and the type found in samples of bulk material.

  10. Comparison of Water Vapor Measurements by Airborne Sun Photometer and Diode Laser Hygrometer on the NASA DC-8

    SciTech Connect (OSTI)

    Livingston, J. M.; Schmid, Beat; Russell, P. B.; Podolske, James R.; Redemann, Jens; Diskin, G. S.

    2008-10-29

    In January-February 2003 the 14-channel NASA Ames Airborne Tracking Sunphotometer 30 (AATS) and the NASA Langley/Ames Diode Laser Hygrometer (DLH) were flown on the NASA DC-8 aircraft. AATS measured column water vapor on the aircraft-to-sun path, while DLH measured local water vapor in the free stream between the aircraft fuselage and an outboard engine cowling. The AATS and DLH measurements were compared for two DC-8 vertical profiles by differentiating the AATS column measurement and/or integrating the DLH local measurement over the altitude range of each profile (7.7-10 km and 1.2-12.5 km). These comparisons extend, for the first time, tests of AATS water vapor retrievals to altitudes >~6 km and column contents <0.1 g cm-2. To our knowledge this is the first time suborbital spectroscopic water vapor measurements using the 940-nm band have been tested in conditions so high and dry. For both profiles layer water vapor (LWV) from AATS and DLH were highly correlated, with r2 0.998, rms difference 7.2% and bias (AATS minus DLH) 0.9%. For water vapor densities AATS and DLH had r2 0.968, rms difference 27.6%, and bias (AATS minus DLH) -4.2%. These results compare favorably with previous comparisons of AATS water vapor to in situ results for altitudes <~6 km, columns ~0.1 to 5 g cm-2 and densities ~0.1 to 17 g m-3.

  11. Spatio-spectral characteristics of parametric down-conversion in waveguide arrays

    E-Print Network [OSTI]

    Regina Kruse; Fabian Katzschmann; Andreas Christ; Andreas Schreiber; Sarah Wilhelm; Kaisa Laiho; Aurél Gábris; Craig S. Hamilton; Igor Jex; Christine Silberhorn

    2013-08-27

    High dimensional quantum states are of fundamental interest for quantum information processing. They give access to large Hilbert spaces and, in turn, enable the encoding of quantum information on multiple modes. One method to create such quantum states is parametric down-conversion (PDC) in waveguide arrays (WGAs) which allows for the creation of highly entangled photon-pairs in controlled, easily accessible spatial modes, with unique spectral properties. In this paper we examine both theoretically and experimentally the PDC process in a lithium niobate WGA. We measure the spatial and spectral properties of the emitted photon-pairs, revealing strong correlations between spectral and spatial degrees of freedom of the created photons. Our measurements show that, in contrast to prior theoretical approaches, spectrally dependent coupling effects have to be taken into account in the theory of PDC in WGAs. To interpret the results, we developed a theoretical model specifically taking into account spectrally dependent coupling effects, which further enables us to explore the capabilities and limitations for engineering the spatial correlations of the generated quantum states.

  12. Tonopah Test Range Air Monitoring: CY2012 Meteorological, Radiological, and Airborne Particulate Observations

    SciTech Connect (OSTI)

    Mizell, Steve A; Nikolich, George; Shadel, Craig; McCurdy, Greg; Miller, Julianne J

    2013-07-01

    In 1963, the Atomic Energy Commission (AEC), predecessor to the US Department of Energy (DOE), implemented Operation Roller Coaster on the Tonopah Test Range (TTR) and an adjacent area of the Nevada Test and Training Range (NTTR) (formerly the Nellis Air Force Range (NAFR)). Operation Roller Coaster consisted of four tests in which chemical explosions were detonated in the presence of nuclear devices to assess the dispersal of radionuclides and evaluate the effectiveness of storage structures to contain the ejected radionuclides. These tests resulted in dispersal of plutonium over the ground surface downwind of the test ground zero. Three tests, Clean Slate 1, 2, and 3, were conducted on the TTR in Cactus Flat; the fourth, Double Tracks, was conducted in Stonewall Flat on the NTTR. DOE is working to clean up and close all four sites. Substantial cleaned up has been accomplished at Double Tracks and Clean Slate 1. Cleanup of Clean Slate 2 and 3 is on the DOE planning horizon for some time in the next several years. The Desert Research Institute installed two monitoring stations, number 400 at the Sandia National Laboratories Range Operations Center and number 401 at Clean Slate 3, in 2008 and a third monitoring station, number 402 at Clean Slate 1, in 2011 to measure radiological, meteorological, and dust conditions. The primary objectives of the data collection and analysis effort are to (1) monitor the concentration of radiological parameters in dust particles suspended in air, (2) determine whether winds are re-distributing radionuclides or contaminated soil material, (3) evaluate the controlling meteorological conditions if wind transport is occurring, and (4) measure ancillary radiological, meteorological, and environmental parameters that might provide insight to the above assessments. The following observations are based on data collected during CY2012. The mean annual concentration of gross alpha and gross beta is highest at Station 400 and lowest at Station 401. This difference may be the result of using filter media at Station 400 with a smaller pore size than the media used at the other two stations. Average annual gamma exposure at Station 401 is slightly greater than at Station 400 and 402. Average annual gamma exposure at all three TTR stations are in the upper range to slightly higher than values reported for the CEMP stations surrounding the TTR. At higher wind speeds, the saltation counts are greater at Station 401 than at Station 402 while the suspended particulate concentrations are greater at Station 402 than at Statin 401. Although these observations seem counterintuitive, they are likely the result of differences in the soil material present at the two sites. Station 401 is located on an interfluve elevated above two adjacent drainage channels where the soil surface is likely to be composed of coarser material. Station 402 is located in finer sediments at the playa edge and is also subject to dust from a dirt road only 500 m to the north. During prolonged high wind events, suspended dust concentrations at Station 401 peaked with the initial winds then decreased whereas dust concentrations at Station 402 peaked with each peak in the wind speed. This likely reflects a limited PM10 source that is quickly expended at Station 401 relative to an abundant PM10 source at Station 402. In CY2013, to facilitate comparisons between radiological analyses of collected dust, the filter media at all three stations will be standardized. In addition, a sequence of samples will be collected at Station 400 using both types of filter media to enable development of a mathematical relationship between the results derived from the two filter types. Additionally, having acquired approximately four years of observations at Stations 400 and 401 and a year of observations at Station 402, a period-of-record analysis of the radiological and airborne dust conditions will be undertaken.

  13. Spectral problems of optical waveguides and quantum graphs 

    E-Print Network [OSTI]

    Ong, Beng Seong

    2006-10-30

    In this dissertation, we consider some spectral problems of optical waveguide and quantum graph theories. We study spectral problems that arise when considerating optical waveguides in photonic band-gap (PBG) materials. Specifically, we address...

  14. Wave spectral energy variability in the northeast Peter D. Bromirski

    E-Print Network [OSTI]

    Bromirski, Peter D.

    Wave spectral energy variability in the northeast Pacific Peter D. Bromirski Integrative January 2005; published 8 March 2005. [1] The dominant characteristics of wave energy variability] s wave spectral energy components are considered separately. Empirical orthogonal function (EOF) analyses

  15. Spectral Change of Hadrons and Chiral Symmetry

    E-Print Network [OSTI]

    Tetsuo Hatsuda

    2001-04-16

    After a brief summary of the QCD phase structure with light quarks, we discuss two recent developments on in-medium hadrons. First topic is the sigma-meson which is a fluctuation of the chiral order parameter \\bar{q}q. Although sigma is at best a broad resonance in the vacuum, it may suffer a substantial red-shift and show a characteristic spectral enhancement at the 2 m_{pi} threshold at finite temperature and baryon density. Possible experimental signatures of this phenomenon are also discussed. Another topic is the first principle lattice QCD calculation of the hadronic spectral functions using the maximum entropy method (MEM). The basic idea and a successful example of MEM are presented. Possible applications of MEM to study the in-medium hadrons in lattice QCD simulations are discussed.

  16. Laser stabilization using spectral hole burning

    E-Print Network [OSTI]

    L. Rippe; B. Julsgaard; A. Walther; S. Kröll

    2006-11-05

    We have frequency stabilized a Coherent CR699-21 dye laser to a transient spectral hole on the 606 nm transition in Pr^{+3}:Y_2SiO_5. A frequency stability of 1 kHz has been obtained on the 10 microsecond timescale together with a long-term frequency drift below 1 kHz/s. RF magnetic fields are used to repopulate the hyperfine levels allowing us to control the dynamics of the spectral hole. A detailed theory of the atomic response to laser frequency errors has been developed which allows us to design and optimize the laser stabilization feedback loop, and specifically we give a stability criterion that must be fulfilled in order to obtain very low drift rates. The laser stability is sufficient for performing quantum gate experiments in Pr^{+3}:Y_2SiO_5.

  17. Fiberoptic probe and system for spectral measurements

    DOE Patents [OSTI]

    Dai, S.; Young, J.P.

    1998-10-13

    A fused fiberoptic probe, a system, method and embodiments thereof for conducting spectral measurements are disclosed. The fused fiberoptic probe comprises a probe tip having a specific geometrical configuration, an exciting optical fiber and at least one collection optical fiber fused within a housing, preferably silica. The specific geometrical configurations in which the probe tip can be shaped include a slanted probe tip with an angle greater than 0{degree}, an inverted cone-shaped probe tip, and a lens head. 12 figs.

  18. Conditionally Convergent Spectral Sequences Contents Introduction

    E-Print Network [OSTI]

    that depend on data internal to the spectral sequence, they lead to satisfactory. convergence and .... For the higher terms, we de ne for all integers s and all r 1: Z. s. r = k 1 (Im[i (r 1) : A .... this is the convergence problem, and is the subject of Part II. Morphisms of .... Otherwise, although it is clear that knowledge of the groups.

  19. EFFICIENT SPECTRAL-GALERKIN METHODS III: POLAR AND ...

    E-Print Network [OSTI]

    1999-10-21

    EFFICIENT SPECTRAL-GALERKIN METHODS III: POLAR AND CYLINDRICAL GEOMETRIES. ?. JIE SHEN†. SIAM J. SCI. COMPUT. c 1997 Society for ...

  20. Spectral resolution in hyperbolic orbifolds, quantum chaos, and cosmology

    E-Print Network [OSTI]

    H. Then

    2007-12-28

    We present a few subjects from physics that have one in common: the spectral resolution of the Laplacian.

  1. Noise Reduction and Increased VAD Accuracy Using Spectral Subtraction

    E-Print Network [OSTI]

    Brown III, Donald R.

    algorithm. The more accurate VAD after the first spectral subtraction is then used to reprocess the original

  2. Black Hole Spectral States and Physical Connections

    E-Print Network [OSTI]

    John A. Tomsick

    2005-09-06

    The dramatic changes seen in the X-ray spectral and timing properties of accreting black hole candidates (BHCs) provide important clues about the accretion and jet formation processes that occur in these systems. Dividing the different source behaviors into spectral states provides a framework for studying BHCs. To date, there have been three main classification schemes with Luminosity-based, Component-based, or Transition-based criteria. The canonical, Luminosity-based criteria and physical models that are based on this concept do not provide clear explanations for several phenomena, including hysteresis of spectral states and the presence of jets. I discuss the re-definitions of states, focusing on an application of the Component-based states to more than 400 RXTE observations of the recurrent BHC 4U 1630-47. We compare the X-ray properties for the recent 2002-2004 outburst to those of an earlier (1998) outburst, during which radio jets were observed. The results suggest a connection between hysteresis of states and major jet ejections, and it is possible that both of these are related to the evolution of the inner radius of the optically thick accretion disk.

  3. High field, high efficiency terahertz pulse generation by optical rectification

    E-Print Network [OSTI]

    Huang, Wenqian Ronny

    2014-01-01

    The great difficulty of producing high intensity radiation in the terahertz (THz) spectral region by conventional electronics has stimulated interest in development of sources based on photonics. Optical rectification in ...

  4. Pseudo-spectral 3D simulations of streamers with adaptively refined grids

    E-Print Network [OSTI]

    Ebert, Ute

    -ionization. The electric field created by the space charges is solved self-consistently. The code assumes that the streamer of multiprocessor machines, a pseudo-spectral method (applying discrete Fourier transform forth and back at each of electrical breakdown in large volumes is the streamer: under a high enough electric field an accumulation

  5. Spectral Label Fusion Christian Wachinger1,2

    E-Print Network [OSTI]

    Golland, Polina

    off. The segmentation with spectral label fusion, which fuses image and label information, leadsSpectral Label Fusion Christian Wachinger1,2 and Polina Golland1 1 Computer Science and Artificial a new segmentation approach that combines the strengths of label fusion and spectral clustering

  6. Emergency Response Equipment and Related Training: Airborne Radiological Computer System (Model II)

    SciTech Connect (OSTI)

    David P. Colton

    2007-02-28

    The materials included in the Airborne Radiological Computer System, Model-II (ARCS-II) were assembled with several considerations in mind. First, the system was designed to measure and record the airborne gamma radiation levels and the corresponding latitude and longitude coordinates, and to provide a first overview look of the extent and severity of an accident's impact. Second, the portable system had to be light enough and durable enough that it could be mounted in an aircraft, ground vehicle, or watercraft. Third, the system must control the collection and storage of the data, as well as provide a real-time display of the data collection results to the operator. The notebook computer and color graphics printer components of the system would only be used for analyzing and plotting the data. In essence, the provided equipment is composed of an acquisition system and an analysis system. The data can be transferred from the acquisition system to the analysis system at the end of the data collection or at some other agreeable time.

  7. Health physics manual of good practices for the prompt detection of airborne plutonium in the workplace

    SciTech Connect (OSTI)

    Not Available

    1988-07-01

    This manual provides guidance to US Department of Energy (DOE) facilities on the prompt detection of airborne plutonium in the workplace. Information is first given to aid in detection systems that will function effectively in various workplaces. Steps in designing a system are covered: its general requirements, the plotting of workplace sources of plutonium, and methods of determining workplace airflow patterns. Guidance is provided on the proper numbers and locations of probe sites, the orientation of probes for representative sampling, and the mixture of stationary and portable probes. Recommendations for delivery in sampling systems include examination of particle loss and self-absorption problems, methods of eliminating air leakage in the system, and optimization of decontamination capabilities. System flow rate, requirements in a collection medium, burial loss and pressure drop, and prudent frequency of renewing the collection medium are among air sampling considerations covered. After a discussion of controlling airflow and of vacuum sources and system backups, the checkpoints to ensure system reliability are listed. The manual then discusses instrument specifications that provide correct airborne plutonium concentrations and reliably activate alarms. Focusing on the interrelationship of all components, essential factors in instrument reliability are addressed: the regulatory lower limit of detection and performance specifications of detectors and filters, maintenance and calibration requirements, and features of commonly used plutonium air-sampling instruments. Finally, the manual advises on establishing a documentation program to archive and evaluate the performance of a plutonium air-sampling program.

  8. Pulsar Emission above the Spectral Break - A Stacked Approach

    E-Print Network [OSTI]

    McCann, Andrew

    2015-01-01

    NASA's Fermi space telescope has provided us with a bountiful new population of gamma-ray sources following its discovery of 150 new gamma-ray pulsars. One common feature exhibited by all of these pulsars is the form of their spectral energy distribution, which can be described by a power law followed by a spectral break occurring between $\\sim$1 and $\\sim$8 GeV. The common wisdom is that the break is followed by an exponential cut-off driven by radiation/reaction-limited curvature emission. The discovery of pulsed gamma rays from the Crab pulsar, the only pulsar so far detected at very high energies (E$>$100GeV), contradicts this "cutoff" picture. Here we present a new stacked analysis with an average of 4.2 years of data on 115 pulsars published in the 2nd LAT catalog of pulsars. This analysis is sensitive to low-level $\\sim$100 GeV emission which cannot be resolved in individual pulsars but can be detected from an ensemble.

  9. Spectral statistics in noninteracting many-particle systems

    SciTech Connect (OSTI)

    Munoz, L.; Relano, A.; Retamosa, J. [Departamento de Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid, E-28040 Madrid (Spain); Faleiro, E. [Departamento de Fisica Aplicada, E.U.I.T. Industrial, Universidad Politecnica de Madrid, E-28012 Madrid (Spain); Molina, R.A. [Max-Planck-Institut fuer Physik Komplexer Systeme, Noethnitzer Strasse 38, D-01187 Dresden (Germany)

    2006-03-15

    It is widely accepted that the statistical properties of energy level spectra provide an essential characterization of quantum chaos. Indeed, the spectral fluctuations of many different systems like quantum billiards, atoms, or atomic nuclei have been studied. However, noninteracting many-body systems have received little attention, since it is assumed that they must exhibit Poisson-like fluctuations. Apart from a heuristic argument of Bloch, there are neither systematic numerical calculations nor a rigorous derivation of this fact. Here we present a rigorous study of the spectral fluctuations of noninteracting identical particles moving freely in a mean field emphasizing the evolution with the number of particles N as well as with the energy. Our results are conclusive. For N{>=}2 the spectra of these systems exhibit Poisson fluctuations provided that we consider sufficiently high excitation energies. Nevertheless, when the mean field is chaotic there exists a critical energy scale L{sub c}; beyond this scale, the fluctuations deviate from the Poisson statistics as a reminiscence of the statistical properties of the mean field.

  10. Spectral Energy Distributions of Gamma-ray Blazars

    E-Print Network [OSTI]

    Laura Maraschi; Giovanni Fossati

    1996-12-09

    Average Spectral Energy Distributions (SED) for different subgroups of blazars are derived from available homogeneous (but small) data sets, including the gamma-ray band. Comparing Flat Spectrum Radio Quasars (FSRQ) with BL Lacs extracted from radio (RBL) or X-ray surveys (XBL) remarkable differences and similarities are apparent: i) in all cases the overall SED from radio to gamma-rays shows two peaks; ii) the first and second peak fall in different frequency ranges for different objects, with a tendency for the most luminous objects to peak at lower frequencies; iii) the ratio between the two peak frequencies seems to be constant, while the luminosity ratio between the high and low frequency component increases from XBL to RBL and FSRQ. The variability properties, (amplitude and frequency dependence) are similar in different objects if referred to their respective peak frequencies. Finally, comparing spectral snapshots obtained at different epochs, the intensities of the two components at frequencies close and above their respective peaks seem to be correlated. The relevance of these properties for theoretical models is briefly discussed.

  11. PICK-UP ION DISTRIBUTIONS AND THEIR INFLUENCE ON ENERGETIC NEUTRAL ATOM SPECTRAL CURVATURE

    SciTech Connect (OSTI)

    Livadiotis, G.; McComas, D. J.; Randol, B. M.; Schwadron, N. A.; Dayeh, M. A.; Funsten, H. O.; Moebius, E. S.; Zank, G. P.; Frisch, P. C.

    2012-05-20

    This paper focuses on the analysis and significance of the spectral curvature of energetic neutral atoms (ENAs) detected by the Interstellar Boundary Explorer. The flux versus energy spectrum is analytically expressed in terms of the source proton distributions, namely: (1) the solar wind kappa distribution of protons and (2) the coexisting filled spherical shell distribution of pick-up ions (PUIs). The influence of PUIs on the spectral index and curvature is modeled and investigated in detail. It is analytically shown that (1) the PUI speed upper limit is restricted by the Earthward PUI velocity vector, (2) the PUI distribution causes a positive spectral curvature, and (3) the exact expressions of the spectral index and curvature can be used to extract information about the governing parameters of the parent proton distributions. The sky maps of the spectral curvature reveal a possible band-like configuration of positive spectral curvature that is missing in the original flux sky maps. This band can be roughly separated into the north/south polar regions and two ecliptic meridional 'columns' located around the ecliptic longitudes {approx}5 Degree-Sign and {approx}150 Degree-Sign . The geometric locus between the two cones with noseward axis, and apertures {approx}60 Degree-Sign and {approx}120 Degree-Sign , configures the band-like region of (1) the positive curvature and (2) the maximum values of PUI distribution. Indeed, the observed curvature band is highly correlated with PUI distributions, and is possibly caused by the influence of PUIs on bending the spectrum from linear (log-log scale) to concave upward, thus increasing its spectral curvature.

  12. Tailoring laser pulses with spectral and fluence constraints using optimal control theory

    E-Print Network [OSTI]

    J. Werschnik; E. K. U. Gross

    2005-04-21

    Within the framework of optimal control theory we develop a simple iterative scheme to determine optimal laser pulses with spectral and fluence constraints. The algorithm is applied to a one-dimensional asymmetric double well where the control target is to transfer a particle from the ground state, located in the left well, to the first excited state, located in the right well. Extremely high occupations of the first excited state are obtained for a variety of spectral and/or energetic constraints. Even for the extreme case where no resonance frequency is allowed in the pulse the algorithm achieves an occupation of almost 100%.

  13. Testing the Accuracy and Stability of Spectral Methods in Numerical Relativity

    E-Print Network [OSTI]

    Michael Boyle; Lee Lindblom; Harald Pfeiffer; Mark Scheel; Lawrence E. Kidder

    2007-10-02

    The accuracy and stability of the Caltech-Cornell pseudospectral code is evaluated using the KST representation of the Einstein evolution equations. The basic "Mexico City Tests" widely adopted by the numerical relativity community are adapted here for codes based on spectral methods. Exponential convergence of the spectral code is established, apparently limited only by numerical roundoff error. A general expression for the growth of errors due to finite machine precision is derived, and it is shown that this limit is achieved here for the linear plane-wave test. All of these tests are found to be stable, except for simulations of high amplitude gauge waves with nontrivial shift.

  14. Dissemination and Presentation of High Resolution Air Pollution Data from Mobile Sensor Nodes

    E-Print Network [OSTI]

    Koutsoukos, Xenofon D.

    Dissemination and Presentation of High Resolution Air Pollution Data from Mobile Sensor Nodes method of air pollution monitoring in the United States includes sampling airborne pollutants hourly. Since pollution is highly location de- pendent, there is insufficient data to accurately evaluate air

  15. What happens to the Upsilon and eta_b in the quark-gluon plasma? Bottomonium spectral functions from lattice QCD

    E-Print Network [OSTI]

    Gert Aarts; Chris Allton; Seyong Kim; Maria Paola Lombardo; Mehmet B. Oktay; Sinead M. Ryan; D. K. Sinclair; Jon-Ivar Skullerud

    2011-11-21

    We study bottomonium spectral functions in the quark-gluon plasma in the Upsilon and eta_b channels, using lattice QCD simulations with two flavours of light quark on highly anisotropic lattices. The bottom quark is treated with nonrelativistic QCD (NRQCD). In the temperature range we consider, 0.42 MEM), used to construct the spectral functions, are discussed in some detail.

  16. Semiclassical Analysis of Spectral Singularities and Their Applications in Optics

    E-Print Network [OSTI]

    Ali Mostafazadeh

    2011-05-23

    Motivated by possible applications of spectral singularities in optics, we develop a semiclassical method of computing spectral singularities. We use this method to examine the spectral singularities of a planar slab gain medium whose gain coefficient varies due to the exponential decay of the intensity of pumping beam inside the medium. For both singly- and doubly-pumped samples, we obtain universal upper bounds on the decay constant beyond which no lasing occurs. Furthermore, we show that the dependence of the wavelength of the spectral singularities on the value of the decay constant is extremely mild. This is an indication of the stability of optical spectral singularities.

  17. The Spectral Backbone of Excitation Transport in Ultra-Cold Rydberg Gases

    E-Print Network [OSTI]

    Scholak, Torsten; Buchleitner, Andreas

    2014-01-01

    The spectral structure underlying excitonic energy transfer in ultra-cold Rydberg gases is studied numerically, in the framework of random matrix theory, and via self-consistent diagrammatic techniques. Rydberg gases are made up of randomly distributed, highly polarizable atoms that interact via strong dipolar forces. Dynamics in such a system is fundamentally different from cases in which the interactions are of short range, and is ultimately determined by the spectral and eigenvector structure. In the energy levels' spacing statistics, we find evidence for a critical energy that separates delocalized eigenstates from states that are localized at pairs or clusters of atoms separated by less than the typical nearest-neighbor distance. We argue that the dipole blockade effect in Rydberg gases can be leveraged to manipulate this transition across a wide range: As the blockade radius increases, the relative weight of localized states is reduced. At the same time, the spectral statistics -- in particular, the den...

  18. Spectral structures and their generation mechanisms for solar radio type-I bursts

    SciTech Connect (OSTI)

    Iwai, K. [Nobeyama Solar Radio Observatory, National Astronomical Observatory of Japan, Nobeyama, Nagano 384-1305 (Japan); Miyoshi, Y.; Masuda, S. [Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya, Aichi 464-8601 (Japan); Tsuchiya, F.; Morioka, A.; Misawa, H., E-mail: kazumasa.iwai@nao.ac.jp [Planetary Plasma and Atmospheric Research Center, Tohoku University, Sendai, Miyagi 980-8578 (Japan)

    2014-07-01

    The fine spectral structures of solar radio type-I bursts were observed by the solar radio telescope AMATERAS. The spectral characteristics, such as the peak flux, duration, and bandwidth, of the individual burst elements were satisfactorily detected by the highly resolved spectral data of AMATERAS with the burst detection algorithm that is improved in this study. The peak flux of the type-I bursts followed a power-law distribution with a spectral index of 2.9-3.3, whereas their duration and bandwidth were distributed more exponentially. There were almost no correlations between the peak flux, duration, and bandwidth. That means there was no similarity in the shapes of the burst spectral structures. We defined the growth rate of a burst as the ratio between its peak flux and duration. There was a strong correlation between the growth rate and peak flux. These results suggest that the free energy of type-I bursts that is originally generated by nonthermal electrons is modulated in the subsequent stages of the generation of nonthermal electrons, such as plasma wave generation, radio wave emissions, and propagation. The variation of the timescale of the growth rate is significantly larger than that of the coronal environments. These results can be explained by the situation wherein the source region may have the inhomogeneity of an ambient plasma environment, such as the boundary of open and closed field lines, and the superposition of entire emitted bursts was observed by the spectrometer.

  19. Use of land surface remotely sensed satellite and airborne data for environmental exposure assessment in cancer research

    E-Print Network [OSTI]

    cancer and environmental contaminants, focusing primarily on agricultural chemical exposure assessmentUse of land surface remotely sensed satellite and airborne data for environmental exposure assessment in cancer research SUSAN K. MAXWELLa , JAYMIE R. MELIKERb AND PIERRE GOOVAERTSc a U.S. Geological

  20. Ambient Airborne Solids Concentrations Including Volcanic Ash at Hanford, Washington Sampling Sites Subsequent to the Mount St. Helens Eruption

    SciTech Connect (OSTI)

    Sehmel, G.A.

    1982-12-20

    A major eruption of Mount St. Helens occurred on May 18, 1980. Subsequently, airborne solid concentrations were measured as a function of time at two sites within the southern edge of the fallout plume about 211 km east of Mount St. Helens. This ash was a source for investigating area-wide resuspension. Rain had a variable effect on decreasing airborne concentrations from resuspension. From 0.5 to 1.5 cm of rain were required to significantly reduce airborne solid concentrations through July. For a more aged resuspension source in September, a rain of 2.0 cm had a negligible effect. A monthly average threshold-wind speed for resuspension was defined as 3.6 m/s. For monthly-average wind speeds less than the threshold wind speed, monthly-average airborne concentrations tended to decrease with time. A decrease was recorded between September and October. For this 4-month time period, the half-life was on the order of 50 days, corresponding to a weathering rate of 5.1 year/sup -1/.

  1. A comparison of cloud top heights computed from airborne lidar and MAS radiance data using CO2 slicing

    E-Print Network [OSTI]

    Baum, Bryan A.

    A comparison of cloud top heights computed from airborne lidar and MAS radiance data using CO2]. Other studies have compared CO2- slicing cloud heights with those computed from lidar data [Smith in assessing the accuracy of the CO2-slicing cloud height algorithm. Infrared measurements of upwelling

  2. Spectral variability of GX 339-4 in a hard-to-soft state transition

    E-Print Network [OSTI]

    M. Del Santo; J. Malzac; E. Jourdain; T. Belloni; P. Ubertini

    2008-07-07

    We report on INTEGRAL observations of the bright black-hole transient GX 339-4 performed during the period August-September 2004. Our data cover three different spectral states, namely Hard/Intermediate State, Soft/Intermediate State and High/Soft State. We investigate the spectral variability of the source across the different spectral states. The hard X-ray spectrum becomes softer during the HIMS-to-SIMS transition, but it hardens when reaching the HSS state. A principal component analysis demonstrates that most of the variability occurs through two independent modes: a pivoting of the spectrum around 6 keV (responsible for 75% of the variance) and an intensity variation of the hard component (responsible for 21%). The pivoting is interpreted as due to changes in the soft cooling photon flux entering the corona, the second mode as fluctuations of the heating rate in the corona. Our spectral analysis of the spectra of GX 339-4 shows a high energy excess with respect to pure thermal Comptonisation models in the HIMS: a non-thermal power-law component seems to be requested by data. In all spectral states joint IBIS, SPI and JEM-X data are well represented by hybrid thermal/non-thermal Comptonisation (EQPAIR). The spectral evolution seems to be predominantly driven by a reduction of the ratio of the electron heating rate to the soft cooling photon flux in the corona, l_h/l_s. The inferred accretion disc soft thermal emission increases by about two orders of magnitude, while the Comptonised luminosity decreases by at most a factor of 3. This confirms that the softening we observed is due to a major increase in the flux of soft cooling photons in the corona associated with a modest reduction of the electron heating rate.

  3. Spectral and Polarization Properties of Photospheric Emission From Stratified Jets

    E-Print Network [OSTI]

    Ito, Hirotaka; Matsumoto, Jin; Lee, Shiu-Hang; Tolstov, Alexey; Mao, Jirong; Dainotti, Maria; Mizuta, Akira

    2015-01-01

    We explore the spectral and polarization properties of photospheric emissions from stratified jets in which multiple components, separated by a sharp velocity shear regions, are distributed in lateral direction. Propagation of thermal photons injected at high optical depth region are calculated until they escape from the photosphere. It is found that presence of the lateral structure within the jet leads to non-thermal feature of the spectra and significant polarization signal in the resulting emission. The deviation from thermal spectra as well as the polarization degree tends to be enhanced as the velocity gradient in the shear region increases. In particular, we show that emissions from multi-component jet can reproduce the typical observed spectra of gamma-ray bursts (GRBs) irrespective to the position of the observer when a velocity shear region is closely spaced in various lateral ($\\theta$) positions. The degree of polarization associated in the emission is significant (> few%) at wide range of observe...

  4. Spectral breaks of Alfvenic turbulence in a collisionless plasma

    E-Print Network [OSTI]

    Boldyrev, Stanislav; Xia, Qian; Zhdankin, Vladimir

    2015-01-01

    Recent observations reveal that magnetic turbulence in the nearly colisionless solar wind plasma extends to scales smaller than the plasma microscales, such as ion gyroradius and ion inertial length. Measured breaks in the spectra of magnetic and density fluctuations at high frequencies are thought to be related to the transition from large-scale hydromagnetic to small-scale kinetic turbulence. The scales of such transitions and the responsible physical mechanisms are not well understood however. In the present work we emphasize the crucial role of the plasma parameters in the transition to kinetic turbulence, such as the ion and electron plasma beta, the electron to ion temperature ratio, the degree of obliquity of turbulent fluctuations. We then propose an explanation for the spectral breaks reported in recent observations.

  5. Jets, Disks and Spectral States of Black Holes

    E-Print Network [OSTI]

    Sandip K. Chakrabarti

    2000-12-29

    We show that outflow rates in jets directly depend on the spectral states of black holes. In particular, in soft states, when the Comptonized electrons are cold, outflow rate is close to zero. In hard states, outflow could be steady, but the rate may be very small -- only a few percent of the inflow. In the intermediate states, on the other hand, the outflow rate is the highest -- roughly thirty percent of the inflow. In this case, piled up matter below the sonic surface of the outflow could become optically thick and radiative processes could periodically cool the outflow and produce very interesting effects including transitions between burst (high-count or On) and quiescence (low-count or Off) states such as those observed in GRS 1915+105.

  6. Spectral statistics of nearly unidirectional quantum graphs

    E-Print Network [OSTI]

    Maram Akila; Boris Gutkin

    2015-08-19

    The energy levels of a quantum graph with time reversal symmetry and unidirectional classical dynamics are doubly degenerate and obey the spectral statistics of the Gaussian Unitary Ensemble. These degeneracies, however, are lifted when the unidirectionality is broken in one of the graph's vertices by a singular perturbation. Based on a Random Matrix model we derive an analytic expression for the nearest neighbour distribution between energy levels of such systems. As we demonstrate the result agrees excellently with the actual statistics for graphs with a uniform distribution of eigenfunctions. Yet, it exhibits quite substantial deviations for classes of graphs which show strong scarring.

  7. Modelling spectral emission from fusion plasmas

    SciTech Connect (OSTI)

    Summers, H. P.; Badnell, N. R.; Foster, A. R.; Giunta, A.; Guzman, F.; Menchero, L.; Nicholas, C. H.; O'Mullane, M. G.; Whiteford, A. D.; Meigs, A.; Contributors, JET-EFDA [Department of Physics, University of Strathclyde, Glasgow G4 0NG (United Kingdom); Smithsonian Astrophysical Observatory, Cambridge, MA 02138 (United States); Department of Physics, University of Strathclyde, Glasgow G4 0NG (United Kingdom); Association EURATOM-CCFE Culham Science Centre, Abingdon, OX14 3DB (United Kingdom); JET-EFDA, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom)

    2012-05-25

    The paper is a tribute to Nicol Peacock and has a focus on interests and developments at Culham Laboratory from {approx} 1970 when Nicol led the UKAEA spectroscopy team. The paper charts a little of the evolution of these models and their data through the seventies and eighties on into this century at Culham. The paper concludes with the state of efforts to enable easy, universal access to spectral analysis across the scope of Culham activity, of which it is hoped Nicol would approve.

  8. Spectrally Enhanced Lighting | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:Financing Tool FitsProjectDataSecretaryDepartment7 Annual2 Special Report:405-01Tools » Spectrally

  9. Infrared Spectroscopy of Explosives Residues: Measurement Techniques and Spectral Analysis

    SciTech Connect (OSTI)

    Phillips, Mark C.; Bernacki, Bruce E.

    2015-03-11

    Infrared laser spectroscopy of explosives is a promising technique for standoff and non-contact detection applications. However, the interpretation of spectra obtained in typical standoff measurement configurations presents numerous challenges. Understanding the variability in observed spectra from explosives residues and particles is crucial for design and implementation of detection algorithms with high detection confidence and low false alarm probability. We discuss a series of infrared spectroscopic techniques applied toward measuring and interpreting the reflectance spectra obtained from explosives particles and residues. These techniques utilize the high spectral radiance, broad tuning range, rapid wavelength tuning, high scan reproducibility, and low noise of an external cavity quantum cascade laser (ECQCL) system developed at Pacific Northwest National Laboratory. The ECQCL source permits measurements in configurations which would be either impractical or overly time-consuming with broadband, incoherent infrared sources, and enables a combination of rapid measurement speed and high detection sensitivity. The spectroscopic methods employed include standoff hyperspectral reflectance imaging, quantitative measurements of diffuse reflectance spectra, reflection-absorption infrared spectroscopy, microscopic imaging and spectroscopy, and nano-scale imaging and spectroscopy. Measurements of explosives particles and residues reveal important factors affecting observed reflectance spectra, including measurement geometry, substrate on which the explosives are deposited, and morphological effects such as particle shape, size, orientation, and crystal structure.

  10. MOJAVE: Monitoring of jets in active galactic nuclei with VLBA experiments. XI. Spectral distributions

    SciTech Connect (OSTI)

    Hovatta, Talvikki; Aller, Margo F.; Aller, Hugh D.; Clausen-Brown, Eric; Kovalev, Yuri Y.; Pushkarev, Alexander B.; Savolainen, Tuomas; Homan, Daniel C.; Lister, Matthew L.

    2014-06-01

    We have obtained milliarcsecond-scale spectral index distributions for a sample of 190 extragalactic radio jets through the Monitoring of Jets in Active Galactic Nuclei with the VLBA Experiments (MOJAVE) project. The sources were observed in 2006 at 8.1, 8.4, 12.1, and 15.4 GHz, and we have determined spectral index maps between 8.1 and 15.4 GHz to study the four-frequency spectrum in individual jet features. We have performed detailed simulations to study the effects of image alignment and (u, v)-plane coverage on the spectral index maps to verify our results. We use the spectral index maps to study the spectral index evolution along the jet and determine the spectral distributions in different locations of the jets. The core spectral indices are on average flat with a mean value of +0.22 ± 0.03 for the sample, while the jet spectrum is in general steep with a mean index of –1.04 ± 0.03. A simple power-law fit is often inadequate for the core regions, as expected if the cores are partially self-absorbed. The overall jet spectrum steepens at a rate of about –0.001 to –0.004 per deprojected parsec when moving further out from the core with flat spectrum radio quasars having significantly steeper spectra (mean –1.09 ± 0.04) than the BL Lac objects (mean –0.80 ± 0.05). However, the spectrum in both types of objects flattens on average by ?0.2 at the locations of the jet components indicating particle acceleration or density enhancements along the jet. The mean spectral index at the component locations of –0.81 ± 0.02 corresponds to a power-law index of ?2.6 for the electron energy distribution. We find a significant trend that jet components with linear polarization parallel to the jet (magnetic field perpendicular to the jet) have flatter spectra, as expected for transverse shocks. Compared to quasars, BL Lacs have more jet components with perpendicular magnetic field alignment, which may explain their generally flatter spectra. The overall steepening of the spectra with distance can be explained with radiative losses if the jets are collimating or with the evolution of the high-energy cutoff in the electron spectrum if the jets are conical. This interpretation is supported by a significant correlation with the age of the component and the spectral index, with older components having steeper spectra.

  11. Hyper-spectral scanner design and analysis

    SciTech Connect (OSTI)

    Canavan, G.; Moses, J.; Smith, R.

    1996-06-01

    This is the final report of a two-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). An earlier project produced rough designs for key components of a compact hyper-spectral sensor for environmental and ecological measurements. Such sensors could be deployed on unmanned vehicles, aircraft, or satellites for measurements important to agriculture, the environment, and ecologies. This represents an important advance in remote sensing. Motorola invited us to propose an add-on, proof-of-principle sensor for their Comet satellite, whose primary mission is to demonstrate a channel of the IRIDIUM satellite communications system. Our project converted the preliminary designs from the previous effort into final designs for the telescope, camera, computer and interfaces that constitute the hyper-spectral scanning sensor. The work concentrated on design, fabrication, preliminary integration, and testing of the electronic circuit boards for the computer, data compression board, and interface board for the camera-computer and computer-modulator (transmitter) interfaces.

  12. An overview of airborne radioactive emissions at Los Alamos National Laboratory

    SciTech Connect (OSTI)

    Guevara, F.A.; Dvorak, R.F.

    1987-01-01

    Strict control is essential over any emissions of radioactivity in the ventilation exhaust from facilities where radioactive materials may become airborne. At Los Alamos National Laboratory there are 87 stacks exhausting ventilation air to the environment from operations with a potential for radioactive emissions. These stacks cover the diverse operations at all Laboratory facilities where radioactive materials are handled and require continuous sampling/monitoring to detect levels of contamination. An overview is presented of the operations, associated ventilation exhaust cleanup systems, and analysis of the emissions. In keeping with the as-low-as-reasonably-achievable concept, emissions of radionuclides are reduced whenever practicable. A specific example describing the reduction of emissions from the linear accelerator beam stop area at the Los Alamos Meson Physics Facility during 1985 by a factor of 8 over previous emissions is presented.

  13. Quality Assurance Project Plan for radioactive airborne emissions data compilation and reporting

    SciTech Connect (OSTI)

    Burris, S.A.; Thomas, S.P.

    1994-02-01

    This Quality Assurance Project Plan addresses the quality assurance requirements for compiling data from radioactie aiborne emissions. These data will be reported to the US Environmental Protection Agency, the US Department of Energy, and the Washington State Department of Health. Hanford Site radioactive airborne emissions are reported to the US Environmental Protection Agency in compliance with Title 40, Protection of the Environment, Code of Federal Regulations, Part 61, ``National Emissions Standards for Hazardous Air Pollutants , ``Subpart H, ``National Emissions Standards for Emissions of Radionuclides Other Than Radon From Department of Energy Facilities`` (EPA 1989a). Reporting to US Department of Energy is performed in compliance with requirements of US Department of Energy Order 5400.1, General Environmental Protection Program (DOE 1988a).

  14. THE 2011 JUNE 23 STELLAR OCCULTATION BY PLUTO: AIRBORNE AND GROUND OBSERVATIONS

    SciTech Connect (OSTI)

    Person, M. J.; Bosh, A. S.; Levine, S. E.; Gulbis, A. A. S.; Zangari, A. M.; Zuluaga, C. A.; Sallum, S. [Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139-4307 (United States); Dunham, E. W.; Collins, P.; Bida, T.; Bright, L. [Lowell Observatory, Flagstaff, AZ (United States); Pasachoff, J. M.; Babcock, B. A.; Pandey, S.; Amrhein, D. [Williams College-Hopkins Observatory, Williamstown, MA (United States); Tholen, D. J. [Institute for Astronomy, University of Hawaii, Manoa, HI (United States); Taylor, B. [Boston University, Boston, MA (United States); Wolf, J.; Pfueller, E. [Deutsches SOFIA Institut, Universitaet Stuttgart, Pfaffenwaldring 29, D-70569 Stuttgart (Germany); Meyer, A., E-mail: mjperson@mit.edu [SOFIA Science Center, NASA Ames Research Center, MS 211-1, Moffett Field, CA 94035 (United States); and others

    2013-10-01

    On 2011 June 23, stellar occultations by both Pluto (this work) and Charon (future analysis) were observed from numerous ground stations as well as the Stratospheric Observatory for Infrared Astronomy (SOFIA). This first airborne occultation observation since 1995 with the Kuiper Airborne Observatory resulted in the best occultation chords recorded for the event, in three visible wavelength bands. The data obtained from SOFIA are combined with chords obtained from the ground at the IRTF, the U.S. Naval Observatory Flagstaff Station, and Leeward Community College to give the detailed state of the Pluto-Charon system at the time of the event with a focus on Pluto's atmosphere. The data show a return to the distinct upper and lower atmospheric regions with a knee or kink in the light curve separating them as was observed in 1988, rather than the smoothly transitioning bowl-shaped light curves of recent years. The upper atmosphere is analyzed by fitting a model to all of the light curves, resulting in a half-light radius of 1288 {+-} 1 km. The lower atmosphere is analyzed using two different methods to provide results under the differing assumptions of particulate haze and a strong thermal gradient as causes for the lower atmospheric diminution of flux. These results are compared with those from past occultations to provide a picture of Pluto's evolving atmosphere. Regardless of which lower atmospheric structure is assumed, results indicate that this part of the atmosphere evolves on short timescales with results changing the light curve structures between 1988 and 2006, and then reverting these changes in 2011 though at significantly higher pressures. Throughout these changes, the upper atmosphere remains remarkably stable in structure, again except for the overall pressure changes. No evidence of onset of atmospheric collapse predicted by frost migration models is seen, and the atmosphere appears to be remaining at a stable pressure level, suggesting it should persist at this full level through New Horizon's flyby in 2015.

  15. Geophex Airborne Unmanned Survey System (GAUSS). Topical report, October 1993--September 1996

    SciTech Connect (OSTI)

    1998-12-31

    This document is a Final Technical Report that describes the results of the Geophex Airborne Unmanned Survey System (GAUSS) research project. The objectives were to construct a geophysical data acquisition system that uses a remotely operated unmanned aerial vehicle (UAV) and to evaluate its effectiveness for characterization of hazardous environmental sites. The GAUSS is a data acquisition system that mitigates the potential risk to personnel during geophysical characterization of hazardous or radioactive sites. The fundamental basis of the GAUSS is as follows: (1) an unmanned survey vehicle carries geophysical sensors into a hazardous location, (2) the pilot remains outside the hazardous site and operates the vehicle using radio control, (3) geophysical measurements and their spatial locations are processed by an automated data-acquisition system which displays data on an off-site monitor in real-time, and (4) the pilot uses the display to direct the survey vehicle for complete site coverage. The objective of our Phase I research was to develop a data acquisition and processing (DAP) subsystem and geophysical sensors suitable for UAV deployment. We integrated these two subsystems to produce an automated, hand-held geophysical surveying system. The objective of the Phase II effort was to modify the subsystems and integrate them into an airborne prototype. The completed GAUSS DAP system consists of a UAV platform, a laser tracking and ranging subsystem, a telemetry subsystem, light-weight geophysical sensors, a base-station computer (BC), and custom-written survey control software (SCS). We have utilized off-the-shelf commercial products, where possible, to reduce cost and design time.

  16. Radio morphology and spectral analysis of cD galaxies in rich and poor galaxy clusters

    E-Print Network [OSTI]

    S. Giacintucci; T. Venturi; M. Murgia; D. Dallacasa; R. Athreya; S. Bardelli; P. Mazzotta; D. J. Saikia

    2007-08-31

    We present a radio morphological study and spectral analysis for a sample of 13 cD galaxies in rich and poor clusters of galaxies.} Our study is based on new high sensitivity Giant Metrewave Radio Telescope (GMRT) observations at 1.28 GHz, 610 MHz and 235 MHz, and on archival data. From a statistical sample of cluster cD galaxies we selected those sources with little information available in the literature and promising for the detection of aged radio emission. Beyond the high sensitivity images for all 13 radio galaxies, we present also a detailed spectral analysis for 7 of them. We found a variety of morphologies and linear sizes, as typical for radio galaxies in the radio power range sampled here (low to intermediate power radio galaxies). The spectral analysis shows that 10/13 radio galaxies have steep radio spectrum, with spectral index $\\alpha \\ge 1$. In general, the radiative ages and growth velocities are consistent with previous findings that the evolution of radio galaxies at the cluster centres is affected by the dense external medium (i.e. low growth velocities and old ages. We suggest that the dominant galaxies in A 2622 and MKW 03s are dying radio sources, which at present are not fed by nuclear activity. On the other hand, the spectacular source at the centre of A 2372 might be a very interesting example of restarted radio galaxy. For this source we estimated a life cycle of the order of 10$^6$ yr.

  17. Graph Based Models for Unsupervised High Dimensional Data Clustering and Network Analysis

    E-Print Network [OSTI]

    Hu, Huiyi

    2015-01-01

    hight-dimensional datasets, in particular hyper-spectralhyper- spectral imagery segmentation and general high-dimensionalhyper-spectral data, where u 0 (n i ) represents the d-dimensional

  18. Periodic Schrödinger operators with local defects and spectral pollution

    E-Print Network [OSTI]

    Eric Cancès; Virginie Ehrlacher; Yvon Maday

    2011-11-16

    This article deals with the numerical calculation of eigenvalues of perturbed periodic Schr\\"odinger operators located in spectral gaps. Such operators are encountered in the modeling of the electronic structure of crystals with local defects, and of photonic crystals. The usual finite element Galerkin approximation is known to give rise to spectral pollution. In this article, we give a precise description of the corresponding spurious states. We then prove that the supercell model does not produce spectral pollution. Lastly, we extend results by Lewin and S\\'er\\'e on some no-pollution criteria. In particular, we prove that using approximate spectral projectors enables one to eliminate spectral pollution in a given spectral gap of the reference periodic Sch\\"odinger operator.

  19. Simulation framework for spatio-spectral anomalous change detection

    SciTech Connect (OSTI)

    Theiler, James P; Harvey, Neal R; Porter, Reid B; Wohlberg, Brendt E

    2009-01-01

    The authors describe the development of a simulation framework for anomalous change detection that considers both the spatial and spectral aspects of the imagery. A purely spectral framework has previously been introduced, but the extension to spatio-spectral requires attention to a variety of new issues, and requires more careful modeling of the anomalous changes. Using this extended framework, they evaluate the utility of spatial image processing operators to enhance change detection sensitivity in (simulated) remote sensing imagery.

  20. IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS, VOL. 14, NO. 1, JANUARY/FEBRUARY 2008 217 Spectral Self-Interference Fluorescence Microscopy

    E-Print Network [OSTI]

    resolution, we de- scribe and demonstrate a high-NA 4Pi microscopy system that per- forms spectral self of the Engineering Research Centers Program, in part by the Air Force Office of Scientific Research un- der Grant

  1. Consequences of Flooding on Spectral Statistics

    E-Print Network [OSTI]

    Torsten Rudolf; Normann Mertig; Steffen Löck; Arnd Bäcker

    2012-04-05

    We study spectral statistics in systems with a mixed phase space, in which regions of regular and chaotic motion coexist. Increasing their density of states, we observe a transition of the level-spacing distribution P(s) from Berry-Robnik to Wigner statistics, although the underlying classical phase-space structure and the effective Planck constant remain unchanged. This transition is induced by flooding, i.e., the disappearance of regular states due to increasing regular-to-chaotic couplings. We account for this effect by a flooding-improved Berry-Robnik distribution, in which an effectively reduced size of the regular island enters. To additionally describe power-law level repulsion at small spacings, we extend this prediction by explicitly considering the tunneling couplings between regular and chaotic states. This results in a flooding- and tunneling-improved Berry-Robnik distribution which is in excellent agreement with numerical data.

  2. Efficient spectral-Galerkin method II. direct solvers for second

    E-Print Network [OSTI]

    1, pp. 74–87, Junuary 1995. 006. Efficient Spectral-Galerkin Method II. Direct Solvers of Second and Fourth Order Equations by Using Chebyshev Polynomials

  3. efficient spectral-galerkin methods iv. spherical geometries

    E-Print Network [OSTI]

    1999-10-21

    EFFICIENT SPECTRAL-GALERKIN METHODS IV. SPHERICAL GEOMETRIES. ?. JIE SHEN†. SIAM J. SCI. COMPUT. c 1999 Society for Industrial and Applied ...

  4. Preliminary Results from Two Spectral-Geobotanical Surveys over...

    Open Energy Info (EERE)

    has included (1) vegetal spectral data, andor (2) biogeochemical data, andor (3) soil geochemical data. The initial results for the Cove Fort Sulphurdale geothermal area...

  5. Spectral Characteristic Evolution: A New Algorithm for Gravitational Wave Propagation

    E-Print Network [OSTI]

    Casey J. Handmer; Béla Szilágyi

    2014-09-24

    We present a spectral algorithm for solving the full nonlinear vacuum Einstein field equations in the Bondi framework. Developed within the Spectral Einstein Code (SpEC), we demonstrate spectral characteristic evolution as a technical precursor to Cauchy Characteristic Extraction (CCE), a rigorous method for obtaining gauge-invariant gravitational waveforms from existing and future astrophysical simulations. We demonstrate the new algorithm's stability, convergence, and agreement with existing evolution methods. We explain how an innovative spectral approach enables a two orders of magnitude improvement in computational efficiency.

  6. Optimal Spectral-Galerkin Methods Using Generalized Jacobi ...

    E-Print Network [OSTI]

    2006-01-07

    Dec 1, 2004 ... We extend the definition of the classical Jacobi polynomials ... KEY WORDS: Generalized Jacobi polynomials; spectral-Galerkin method;.

  7. A Fourier-spectral-element method for transmission eigenvalue

    E-Print Network [OSTI]

    2013-04-22

    Abstract. We develop an efficient spectral-element method for computing the transmission eigenvalues in two-dimensional radially stratified media. Our method.

  8. A time-series study of the health effects of water-soluble and total-extractable metal content of airborne particulate matter 

    E-Print Network [OSTI]

    Heal, Mathew R; Elton, Robert A; Hibbs, Leon R; Agius, Raymond M; Beverland, Iain J

    2009-01-01

    Objectives: To assess whether adverse acute cardiopulmonary health outcomes are associated with concentration of trace metals in airborne particulate matter. Methods: Daily PM10 and PM2.5 was collected for one year in ...

  9. ''A far more formidable task'': the 101st Airborne Division's pacification of Thua Thien Province, Republic of Vietnam, 1968-1972 

    E-Print Network [OSTI]

    Werkheiser, Edwin Brooks, II

    2006-10-30

    This thesis seeks to identify, describe, and analyze the tactics used by the 101st Airborne Division in the pacification of the Republic of Vietnam's Thua Thien province from 1968 to 1972. Despite the larger calamity of ...

  10. Aerosol Properties from Multi-spectral and Multi-angular Aircraft 4STAR Observations: Expected Advantages and Challenges

    SciTech Connect (OSTI)

    Kassianov, Evgueni I.; Flynn, Connor J.; Redemann, Jens; Schmid, Beat; Russell, P. B.; Sinyuk, Alexander

    2012-11-01

    The airborne Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research (4STAR) is developed to retrieve aerosol microphysical and optical properties from multi-angular and multi-spectral measurements of sky radiance and direct-beam sun transmittance. The necessarily compact design of the 4STAR may cause noticeable apparent enhancement of sky radiance at small scattering angles. We assess the sensitivity of expected 4STAR-based aerosol retrieval to such enhancement by applying the operational AERONET retrieval code and constructed synthetic 4STARlike data. Also, we assess the sensitivity of the broadband fluxes and the direct aerosol radiative forcing to uncertainties in aerosol retrievals associated with the sky radiance enhancement. Our sensitivity study results suggest that the 4STARbased aerosol retrieval has limitations in obtaining detailed information on particle size distribution and scattering phase function. However, these limitations have small impact on the retrieved bulk optical parameters, such as the asymmetry factor (up to 4%, or ±0.02) and single-scattering albedo (up to 2%, or ±0.02), and the calculated direct aerosol radiative forcing (up to 6%, or 2 Wm-2).

  11. A comparative study of collection efficiencies using 0.80 and 1.2 micrometer pore size filters in evaluating airborne asbestos dust 

    E-Print Network [OSTI]

    Holt, Grady Lynn

    1974-01-01

    A COMPARATIVE STUDY OF COLLECTION EFFICIENCIES USING O. RO AND 1. 2 MICROMETER PORE SIZE FILTERS IN EVALUATING AIRBORNE ASBESTOS DUST A Thesis by GRADY LYNN HOLT Submitted to the Graduate College of' Texas A&M University in partial... fulfillment of the requirement for the degree of MASTER OF SCIENCE August 1974. Major Subject: Industrial Hygiene A COMPARATIVE . TUDY OF COLLECTION EFFICIENCIES USING O. BO AND 1. 2 MICROMETER PORE SIZE FILTERS IN EVALUATING AIRBORNE ASBESTOS DUST A...

  12. Spatial variations in the spectral index of polarized synchrotron emission in the 9 yr WMAP sky maps

    SciTech Connect (OSTI)

    Fuskeland, U.; Eriksen, H. K.; Næss, S. K. [Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029 Blindern, NO-0315 Oslo (Norway); Wehus, I. K., E-mail: unnif@astro.uio.no, E-mail: h.k.k.eriksen@astro.uio.no, E-mail: s.k.nass@astro.uio.no, E-mail: i.k.wehus@fys.uio.no [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States)

    2014-08-01

    We estimate the spectral index, ?, of polarized synchrotron emission as observed in the 9 yr Wilkinson Microwave Anisotropy Probe sky maps using two methods, linear regression ({sup T}-T plot{sup )} and maximum likelihood. We partition the sky into 24 disjoint sky regions and evaluate the spectral index for all polarization angles between 0° and 85° in steps of 5°. Averaging over polarization angles, we derive a mean spectral index of ?{sup all-sky} = –2.99 ± 0.01 in the frequency range of 23-33 GHz. We find that the synchrotron spectral index steepens by 0.14 from low to high Galactic latitudes, in agreement with previous studies, with mean spectral indices of ?{sup plane} = –2.98 ± 0.01 and ?{sup high-lat} = –3.12 ± 0.04. In addition, we find a significant longitudinal variation along the Galactic plane with a steeper spectral index toward the Galactic center and anticenter than toward the Galactic spiral arms. This can be well modeled by an offset sinusoidal, ?(l) = –2.85 + 0.17sin (2l – 90°). Finally, we study synchrotron emission in the BICEP2 field, in an attempt to understand whether the claimed detection of large-scale B-mode polarization could be explained in terms of synchrotron contamination. Adopting a spectral index of ? = –3.12, typical for high Galactic latitudes, we find that the most likely bias corresponds to about 2% of the reported signal (r = 0.003). The flattest index allowed by the data in this region is ? = –2.5, and under the assumption of a straight power-law frequency spectrum, we find that synchrotron emission can account for at most 20% of the reported BICEP2 signal.

  13. Large Blue Spectral Isocurvature Spectral Index Signals Time-Dependent Mass

    E-Print Network [OSTI]

    Chung, Daniel J H

    2015-01-01

    We show that if a spectator linear isocurvature dark matter field degree of freedom has a constant mass through its entire evolution history, the maximum measurable isocurvature spectral index that is consistent with the current tensor-to-scalar ratio bound is about 2.4, even if experiments can be sensitive to a $10^{-6}$ contamination of the predominantly adiabatic power spectrum with an isocurvature power spectrum at the shortest observable length scales. Hence, any foreseeable future measurement of a blue isocurvature spectral index larger than about 2.4 may provide nontrivial evidence for dynamical degrees of freedom with time-dependent masses during inflation. The bound is not sensitive to the details of the reheating scenario and can be made mildly smaller if the tensor-to-scalar ratio is better constrained in the future.

  14. Large Blue Spectral Isocurvature Spectral Index Signals Time-Dependent Mass

    E-Print Network [OSTI]

    Daniel J. H. Chung

    2015-09-19

    We show that if a spectator linear isocurvature dark matter field degree of freedom has a constant mass through its entire evolution history, the maximum measurable isocurvature spectral index that is consistent with the current tensor-to-scalar ratio bound is about 2.4, even if experiments can be sensitive to a $10^{-6}$ contamination of the predominantly adiabatic power spectrum with an isocurvature power spectrum at the shortest observable length scales. Hence, any foreseeable future measurement of a blue isocurvature spectral index larger than about 2.4 may provide nontrivial evidence for dynamical degrees of freedom with time-dependent masses during inflation. The bound is not sensitive to the details of the reheating scenario and can be made mildly smaller if the tensor-to-scalar ratio is better constrained in the future.

  15. The National Airborne Field Experiment Data Sets Walker J.P. 1

    E-Print Network [OSTI]

    Walker, Jeff

    -band Multibeam Radiometer (PLMR), a thermal imager, full-wave transform lidar, tri-spectral scanner and digital Carolina, United States 16. Department of Primary Industries, Australia 17. NSW Department of Environment's water, energy, and carbon cycles. Moreover, soil moisture knowledge is critical in weather and climate

  16. NASA Airborne AVIRIS and DCS Remote Sensing of Coral Reefs Liane Guild a,

    E-Print Network [OSTI]

    Gilbes, Fernando

    , 2000; Hochberg et al., 2003). Research has shown that spectral distinction of reef bottom types (i Bertholda b Foundation of CSU Monterey Bay, NASA Ames Research Center, Moffett Field, CA 94035, USA, PR 00681, USA ­ roy@cacique.uprm.edu d Center for Hemispherical Cooperation in Research and Education

  17. Assessment of Unabated Facility Emission Potentials for Evaluating Airborne Radionuclide Monitoring Requirements at Pacific Northwest National Laboratory - 1999

    SciTech Connect (OSTI)

    DL Edwards; KD Shields; MJ Sula; MY Ballinger

    1999-09-28

    Assessments were performed to evaluate compliance with the airborne radionuclide emission monitoring requirements in the National Emission Standards for Hazardous Air Pollutants (NESHAP--US Code of Federal Regulations, Title 40 Part 61, Subpart H). In these assessments, potential unabated offsite doses were evaluated for emission locations at facilities owned by the US Department of Energy and operated by Pacific Northwest National Laboratory (Pacific Northwest) on the Hanford Site. Two of the facilities evaluated, 325 Building Radiochemical Processing Laboratory, and 331 Building Life Sciences Laboratory met state and federal criteria for continuous sampling of airborne radionuclide emissions. One other building, the 3720 Environmental Sciences Laboratory, was recognized as being in transition with the potential for meeting the continuous sampling criteria.

  18. Metallicities of M Dwarf Planet Hosts from Spectral Synthesis

    E-Print Network [OSTI]

    Jacob L. Bean; G. Fritz Benedict; Michael Endl

    2006-11-02

    We present the first spectroscopic metallicities of three M dwarfs with known or candidate planetary mass companions. We have analyzed high resolution, high signal-to-noise spectra of these stars which we obtained at McDonald Observatory. Our analysis technique is based on spectral synthesis of atomic and molecular features using recently revised cool-star model atmospheres and spectrum synthesis code. The technique has been shown to yield results consistent with the analyses of solar-type stars and allows measurements of M dwarf [M/H] values to 0.12 dex precision. From our analysis, we find [M/H] = -0.12, -0.32, and -0.33 for GJ 876, GJ 436, and GJ 581 respectively. These three M dwarf planet hosts have sub-solar metallicities, a surprising departure from the trend observed in FGK-type stars. This study is the first part of our ongoing work to determine the metallicities of the M dwarfs included in the McDonald Observatory planet search program.

  19. Nonlinear Power Spectral Densities for the Harmonic Oscillator

    E-Print Network [OSTI]

    B. D. Hauer; J. Maciejko; J. P. Davis

    2015-06-13

    In this paper, we discuss a general procedure by which nonlinear power spectral densities (PSDs) of the harmonic oscillator can be calculated in both the quantum and classical regimes. We begin with an introduction of the damped and undamped classical harmonic oscillator, followed by an overview of the quantum mechanical description of this system. A brief review of both the classical and quantum autocorrelation functions (ACFs) and PSDs follow. We then introduce a general method by which the kth-order PSD for the harmonic oscillator can be calculated, where $k$ is any positive integer. This formulation is verified by first reproducing the known results for the $k = 1$ case of the linear PSD. It is then extended to calculate the second-order PSD, useful in the field of quantum measurement, corresponding to the $k = 2$ case of the generalized method. In this process, damping is included into each of the quantum linear and quadratic PSDs, producing realistic models for the PSDs found in experiment. These quantum PSDs are shown to obey the correspondence principle by matching with what was calculated for their classical counterparts in the high temperature, high-Q limit. Finally, we demonstrate that our results can be reproduced using the fluctuation-dissipation theorem, providing an independent check of our resultant PSDs.

  20. Helical mode interactions and spectral transfer processes in magnetohydrodynamic turbulence

    E-Print Network [OSTI]

    Moritz F. Linkmann; Arjun Berera; Mairi E. McKay; Julia Jäger

    2015-08-22

    Spectral transfer processes in magnetohydrodynamic (MHD) turbulence are investigated analytically by decomposition of the velocity and magnetic fields in Fourier space into helical modes. Steady solutions of the dynamical system which governs the evolution of the helical modes are determined, and a stability analysis of these solutions is carried out. The interpretation of the analysis is that unstable solutions lead to energy transfer between the interacting modes while stable solutions do not. From this, a dependence of possible interscale energy and helicity transfers on the helicities of the interacting modes is derived. As expected from the inverse cascade of magnetic helicity in 3D MHD turbulence, mode interactions with like helicities lead to transfer of energy and magnetic helicity to smaller wavenumbers. However, some interactions of modes with unlike helicities also contribute to an inverse energy transfer. As such, an inverse energy cascade for nonhelical magnetic fields is shown to be possible. Furthermore, it is found that high values of the cross-helicity may have an asymmetric effect on forward and reverse transfer of energy, where forward transfer is more quenched in regions of high cross-helicity than reverse transfer. This conforms with recent observations of solar wind turbulence. For specific helical interactions the relation to dynamo action is established.

  1. Helical mode interactions and spectral transfer processes in magnetohydrodynamic turbulence

    E-Print Network [OSTI]

    Moritz F. Linkmann; Arjun Berera; Mairi E. McKay; Julia Jäger

    2015-09-01

    Spectral transfer processes in magnetohydrodynamic (MHD) turbulence are investigated analytically by decomposition of the velocity and magnetic fields in Fourier space into helical modes. Steady solutions of the dynamical system which governs the evolution of the helical modes are determined, and a stability analysis of these solutions is carried out. The interpretation of the analysis is that unstable solutions lead to energy transfer between the interacting modes while stable solutions do not. From this, a dependence of possible interscale energy and helicity transfers on the helicities of the interacting modes is derived. As expected from the inverse cascade of magnetic helicity in 3D MHD turbulence, mode interactions with like helicities lead to transfer of energy and magnetic helicity to smaller wavenumbers. However, some interactions of modes with unlike helicities also contribute to an inverse energy transfer. As such, an inverse energy cascade for nonhelical magnetic fields is shown to be possible. Furthermore, it is found that high values of the cross-helicity may have an asymmetric effect on forward and reverse transfer of energy, where forward transfer is more quenched in regions of high cross-helicity than reverse transfer. This conforms with recent observations of solar wind turbulence. For specific helical interactions the relation to dynamo action is established.

  2. THE FERMI GBM GAMMA-RAY BURST SPECTRAL CATALOG: FOUR YEARS OF DATA

    SciTech Connect (OSTI)

    Gruber, David; Von Ahlefeld, Victoria Weller; Diehl, Roland; Greiner, Jochen; Von Kienlin, Andreas [Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse 1, D-85748 Garching (Germany); Goldstein, Adam; Bhat, P. Narayana; Briggs, Michael S.; Connaughton, Valerie [University of Alabama in Huntsville, 320 Sparkman Drive, Huntsville, AL 35805 (United States); Bissaldi, Elisabetta [Istituto Nazionale di Fisica Nucleare, Sezione di Trieste, I-34127 Trieste (Italy); Byrne, Dave; Fitzpatrick, Gerard; Foley, Suzanne [School of Physics, University College Dublin, Belfield, Stillorgan Road, Dublin 4 (Ireland); Cleveland, William H. [Universities Space Research Association, 320 Sparkman Drive, Huntsville, AL 35805 (United States); Fishman, Gerald J.; Kouveliotou, Chryssa [Space Science Office, VP62, NASA/Marshall Space Flight Center, Huntsville, AL 35812 (United States); Gibby, Melissa; Giles, Misty M. [Jacobs Technology, Inc., Huntsville, AL (United States); Guiriec, Sylvain [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Van der Horst, Alexander J. [Astronomical Institute, University of Amsterdam, Science Park 904, 1098 XH Amsterdam (Netherlands); and others

    2014-03-01

    In this catalog we present the updated set of spectral analyses of gamma-ray bursts (GRBs) detected by the Fermi Gamma-Ray Burst Monitor during its first four years of operation. It contains two types of spectra, time-integrated spectral fits and spectral fits at the brightest time bin, from 943 triggered GRBs. Four different spectral models were fitted to the data, resulting in a compendium of more than 7500 spectra. The analysis was performed similarly but not identically to Goldstein et al. All 487 GRBs from the first two years have been re-fitted using the same methodology as that of the 456 GRBs in years three and four. We describe, in detail, our procedure and criteria for the analysis and present the results in the form of parameter distributions both for the observer-frame and rest-frame quantities. The data files containing the complete results are available from the High-Energy Astrophysics Science Archive Research Center.

  3. The Spectral Backbone of Excitation Transport in Ultra-Cold Rydberg Gases

    E-Print Network [OSTI]

    Torsten Scholak; Thomas Wellens; Andreas Buchleitner

    2014-11-26

    The spectral structure underlying excitonic energy transfer in ultra-cold Rydberg gases is studied numerically, in the framework of random matrix theory, and via self-consistent diagrammatic techniques. Rydberg gases are made up of randomly distributed, highly polarizable atoms that interact via strong dipolar forces. Dynamics in such a system is fundamentally different from cases in which the interactions are of short range, and is ultimately determined by the spectral and eigenvector structure. In the energy levels' spacing statistics, we find evidence for a critical energy that separates delocalized eigenstates from states that are localized at pairs or clusters of atoms separated by less than the typical nearest-neighbor distance. We argue that the dipole blockade effect in Rydberg gases can be leveraged to manipulate this transition across a wide range: As the blockade radius increases, the relative weight of localized states is reduced. At the same time, the spectral statistics -- in particular, the density of states and the nearest neighbor level spacing statistics -- exhibits a transition from approximately a 1-stable L\\'evy to a Gaussian orthogonal ensemble. Deviations from random matrix statistics are shown to stem from correlations between interatomic interaction strengths that lead to an asymmetry of the spectral density and profoundly affect localization properties. We discuss approximations to the self-consistent Matsubara-Toyozawa locator expansion that incorporate these effects.

  4. Hidden Markov model approach to spectral analysis for hyperspectral imagery

    E-Print Network [OSTI]

    Du, Jenny (Qian)

    divergence (HMMID), is derived to characterize spectral properties. To evaluate the performance of this new). The experimental results show that the HMMID per- forms better than the other three measures in characterizing characterization; spectral information divergence. Paper 990515 received Dec. 27, 1999; revised manuscript received

  5. Investigation into Spectral Parameters as they Impact CPV Module Performance

    SciTech Connect (OSTI)

    Muller, M.; Marion, B.; Kurtz, S.; Rodriguez, J.

    2011-03-01

    The CPV industry is well aware that performance of triple junction cells depends on spectral conditions but there is a lack of data quantifying this spectral dependence at the module level. This paper explores the impact of precipitable water vapor, aerosol optical depth (AOD), and optical air mass on multiple CPV module technologies on-sun in Golden, CO.

  6. Seeing red in cyclic stratigraphy: Spectral noise estimation for astrochronology

    E-Print Network [OSTI]

    Meyers, Stephen R.

    Seeing red in cyclic stratigraphy: Spectral noise estimation for astrochronology Stephen R. Meyers1.8% confidence level). Citation: Meyers, S. R. (2012), Seeing red in cyclic stratigraphy: Spectral noise is the time increment, rn is the red noise sequence, 0 r

  7. On Gravity, Torsion and the Spectral Action Principle

    E-Print Network [OSTI]

    Frank Pfaeffle; Christoph A. Stephan

    2011-06-03

    We consider compact Riemannian spin manifolds without boundary equipped with orthogonal connections. We investigate the induced Dirac operators and the associated commutative spectral triples. In case of dimension four and totally anti-symmetric torsion we compute the Chamseddine-Connes spectral action, deduce the equations of motions and discuss critical points.

  8. Custom Spectral Shaping for EMI Reduction in Electronic Ballasts

    E-Print Network [OSTI]

    waveforms, resulting in the elimination of power spectral density (PSD) distortion and reduced peak currents power and light color, increase lifetime and realize smaller and lighter ballasts. With such a source used extensively to reduce EMI in power supplies [1-10]. The power spectral density (PSD) is spread

  9. Spectral phase encoded time spread optical code division multiple

    E-Print Network [OSTI]

    Yoo, S. J. Ben

    -CDMA, efficient and compact W-CDMA chip develop- ment allowed rapid market-driven transition from the conventionalSpectral phase encoded time spread optical code division multiple access technology for next and summarize the progress of the spectral phase encoded time spreading (SPECTS) optical code division multiple

  10. SPECTRAL SOLAR IRRADIANCE AND ITS ENTROPIC EFFECT ON EARTH'S CLIMATE

    E-Print Network [OSTI]

    SPECTRAL SOLAR IRRADIANCE AND ITS ENTROPIC EFFECT ON EARTH'S CLIMATE Wei Wu1 , Yangang Liu1 of the spectral solar irradiance (SSI) at the top of the Earth's atmosphere by the Solar Radiation and Climate the total solar irradiance (TSI) at the top of the Earth's atmosphere (TOA) varies little (only about 0

  11. Collecting Light with Telescopes Two Fundamentally Different Spectral Mechanisms

    E-Print Network [OSTI]

    Shirley, Yancy

    ;Observing problems due to Earth's atmosphere 1. Light Pollution #12;Star viewed with ground-based telescope. · Location/technology can help overcome light pollution and turbulence. · Nothing short of going to space canCollecting Light with Telescopes #12;Two Fundamentally Different Spectral Mechanisms Spectral lines

  12. Spectral Cascade and Energy Dissipation in Kinetic Alfven Wave Turbulence

    E-Print Network [OSTI]

    Lin, Zhihong

    Spectral Cascade and Energy Dissipation in Kinetic Alfv´en Wave Turbulence Xi Cheng, Zhihong Lin energy sources at large spatial scales. The energy of these non- linearly interacting Alfven waves. 2000). The wave-particle energy exchange rates of these channels depend on the spectral properties near

  13. Optimized Field Sampling and Monitoring of Airborne Hazardous Transport Plumes; A Geostatistical Simulation Approach

    SciTech Connect (OSTI)

    Chen, DI-WEN

    2001-11-21

    Airborne hazardous plumes inadvertently released during nuclear/chemical/biological incidents are mostly of unknown composition and concentration until measurements are taken of post-accident ground concentrations from plume-ground deposition of constituents. Unfortunately, measurements often are days post-incident and rely on hazardous manned air-vehicle measurements. Before this happens, computational plume migration models are the only source of information on the plume characteristics, constituents, concentrations, directions of travel, ground deposition, etc. A mobile ''lighter than air'' (LTA) system is being developed at Oak Ridge National Laboratory that will be part of the first response in emergency conditions. These interactive and remote unmanned air vehicles will carry light-weight detectors and weather instrumentation to measure the conditions during and after plume release. This requires a cooperative computationally organized, GPS-controlled set of LTA's that self-coordinate around the objectives in an emergency situation in restricted time frames. A critical step before an optimum and cost-effective field sampling and monitoring program proceeds is the collection of data that provides statistically significant information, collected in a reliable and expeditious manner. Efficient aerial arrangements of the detectors taking the data (for active airborne release conditions) are necessary for plume identification, computational 3-dimensional reconstruction, and source distribution functions. This report describes the application of stochastic or geostatistical simulations to delineate the plume for guiding subsequent sampling and monitoring designs. A case study is presented of building digital plume images, based on existing ''hard'' experimental data and ''soft'' preliminary transport modeling results of Prairie Grass Trials Site. Markov Bayes Simulation, a coupled Bayesian/geostatistical methodology, quantitatively combines soft information regarding contaminant location with hard experimental results. Soft information is used to build an initial conceptual image of where contamination is likely to be. As experimental data are collected and analyzed, indicator kriging is used to update the initial conceptual image. The sequential Gaussian simulation is then practiced to make a comparison between the two simulations. Simulated annealing is served as a postprocessor to improve the result of Markov Bayes simulation or sequential Gaussian simulation.

  14. 2D radiative modelling of He I spectral lines formed in solar prominences

    E-Print Network [OSTI]

    L. Leger; F. Paletou

    2008-07-11

    We present preliminary results of 2D radiative modelling of He I lines in solar prominences, using a new numerical code developed by us (Leger, Chevallier and Paletou 2007). It treats self-consistently the radiation transfer and the non-LTE statistical equilibrium of H and, in a second stage, the one of He using a detailed atomic model. Preliminary comparisons with new visible plus near-infrared observations made at high spectral resolution with THeMIS are very satisfactory.

  15. Direct Characterization of Airborne Particles Associated with Arsenic-rich Mine Tailings: Particle Size Mineralogy and Texture

    SciTech Connect (OSTI)

    M Corriveau; H Jamieson; M Parsons; J Campbell; A Lanzirotti

    2011-12-31

    Windblown and vehicle-raised dust from unvegetated mine tailings can be a human health risk. Airborne particles from As-rich abandoned Au mine tailings from Nova Scotia, Canada have been characterized in terms of particle size, As concentration, As oxidation state, mineral species and texture. Samples were collected in seven aerodynamically fractionated size ranges (0.5-16 {micro}m) using a cascade impactor deployed at three tailings fields. All three sites are used for recreational activities and off-road vehicles were racing on the tailings at two mines during sample collection. Total concentrations of As in the <8 {micro}m fraction varied from 65 to 1040 ng/m{sup 3} of air as measured by proton-induced X-ray emission (PIXE) analysis. The same samples were analysed by synchrotron-based microfocused X-ray absorption near-edge spectroscopy ({micro}XANES) and X-ray diffraction ({micro}XRD) and found to contain multiple As-bearing mineral species, including Fe-As weathering products. The As species present in the dust were similar to those observed in the near-surface tailings. The action of vehicles on the tailings surface may disaggregate material cemented with Fe arsenate and contribute additional fine-grained As-rich particles to airborne dust. Results from this study can be used to help assess the potential human health risks associated with exposure to airborne particles from mine tailings.

  16. Quantum Graphs: Applications to Quantum Chaos and Universal Spectral Statistics

    E-Print Network [OSTI]

    Sven Gnutzmann; Uzy Smilansky

    2006-12-15

    During the last years quantum graphs have become a paradigm of quantum chaos with applications from spectral statistics to chaotic scattering and wave function statistics. In the first part of this review we give a detailed introduction to the spectral theory of quantum graphs and discuss exact trace formulae for the spectrum and the quantum-to-classical correspondence. The second part of this review is devoted to the spectral statistics of quantum graphs as an application to quantum chaos. Especially, we summarise recent developments on the spectral statistics of generic large quantum graphs based on two approaches: the periodic-orbit approach and the supersymmetry approach. The latter provides a condition and a proof for universal spectral statistics as predicted by random-matrix theory.

  17. Quantitative Analysis of Spectral Impacts on Silicon Photodiode Radiometers

    SciTech Connect (OSTI)

    Myers, D. R.

    2011-01-01

    Inexpensive broadband pyranometers with silicon photodiode detectors have a non-uniform spectral response over the spectral range of 300-1100 nm. The response region includes only about 70% to 75% of the total energy in the terrestrial solar spectral distribution from 300 nm to 4000 nm. The solar spectrum constantly changes with solar position and atmospheric conditions. Relative spectral distributions of diffuse hemispherical irradiance sky radiation and total global hemispherical irradiance are drastically different. This analysis convolves a typical photodiode response with SMARTS 2.9.5 spectral model spectra for different sites and atmospheric conditions. Differences in solar component spectra lead to differences on the order of 2% in global hemispherical and 5% or more in diffuse hemispherical irradiances from silicon radiometers. The result is that errors of more than 7% can occur in the computation of direct normal irradiance from global hemispherical irradiance and diffuse hemispherical irradiance using these radiometers.

  18. Quantitative Analysis of Spectral Impacts on Silicon Photodiode Radiometers: Preprint

    SciTech Connect (OSTI)

    Myers, D. R.

    2011-04-01

    Inexpensive broadband pyranometers with silicon photodiode detectors have a non-uniform spectral response over the spectral range of 300-1100 nm. The response region includes only about 70% to 75% of the total energy in the terrestrial solar spectral distribution from 300 nm to 4000 nm. The solar spectrum constantly changes with solar position and atmospheric conditions. Relative spectral distributions of diffuse hemispherical irradiance sky radiation and total global hemispherical irradiance are drastically different. This analysis convolves a typical photodiode response with SMARTS 2.9.5 spectral model spectra for different sites and atmospheric conditions. Differences in solar component spectra lead to differences on the order of 2% in global hemispherical and 5% or more in diffuse hemispherical irradiances from silicon radiometers. The result is that errors of more than 7% can occur in the computation of direct normal irradiance from global hemispherical irradiance and diffuse hemispherical irradiance using these radiometers.

  19. Multitemporal spectral analysis for cheatgrass (Bromus tectorum) classification.

    SciTech Connect (OSTI)

    Singh, Nagendra; Glenn, Nancy F

    2009-07-01

    Operational satellite remote sensing data can provide the temporal repeatability necessary to capture phenological differences among species. This study develops a multitemporal stacking method coupled with spectral analysis for extracting information from Landsat imagery to provide species-level information. Temporal stacking can, in an approximate mathematical sense, effectively increase the 'spectral' resolution of the system by adding spectral bands of several multitemporal images. As a demonstration, multitemporal linear spectral unmixing is used to successfully delineate cheatgrass (Bromus tectorum) from soil and surrounding vegetation (77% overall accuracy). This invasive plant is an ideal target for exploring multitemporal methods because of its phenological differences with other vegetation in early spring and, to a lesser degree, in late summer. The techniques developed in this work are directly applicable for other targets with temporally unique spectral differences.

  20. Spectral analysis of Fermi-LAT blazars above 50 GeV

    E-Print Network [OSTI]

    Domínguez, Alberto

    2015-01-01

    We present an analysis of the intrinsic (unattenuated by the extragalactic background light, EBL) power-law spectral indices of 128 extragalactic sources detected up to z~2 with the Fermi-Large Area Telescope (LAT) at very high energies (VHEs, E>50 GeV). The median of the intrinsic index distribution is 2.20 (versus 2.54 for the observed distribution). We also analyze the observed spectral breaks (i.e., the difference between the VHE and high energy, HE, 100 MeVspectral indices). The LAT has now provided a large sample of sources detected both at VHE and HE with comparable exposure that allows us to test models of extragalactic gamma-ray photon propagation. We find that our data are compatible with simulations that include intrinsic blazar curvature and EBL attenuation. There is also no evidence of evolution with redshift of the physics that drives the photon emission in high-frequency synchrotron peak (HSP) blazars. This makes HSP blazars excellent probes of the EBL.

  1. Temporal and spectral properties of quantum light

    E-Print Network [OSTI]

    Birgit Stiller; Ulrich Seyfarth; Gerd Leuchs

    2014-11-26

    The modes of the electromagnetic field are solutions of Maxwell's equations taking into account the material boundary conditions. The field modes of classical optics - properly normalized - are also the mode functions of quantum optics. Quantum physics adds that the excitation within each mode is quantized in close analogy to the harmonic oscillator. A complete set of mode functions forms a basis with which any new modes can be reconstructed. In full generality each electromagnetic mode function in the four dimensional space-time is mathematically equivalent to a harmonic oscillator. The quantization of the electromagnetic field defines the excitation per mode and the correlation between modes. In classical optics there can be oscillations and stochastic fluctuations of amplitude, phase, polarization et cetera. In quantum optics there are in addition uncertain quantum field components, quantum correlations and quantized energies. Here, we present selected topics from classical to quantum optics. We start in the second chapter with the classical optics description of a light field and its spectral densities, their measurement and their interpretation. In the third chapter the quantum properties of a single light mode are reviewed as well as ways to measure these quantum properties. Gaussian states of a light mode are emphasized, i. e. states for which the Wigner function has a two dimensional Gaussian shape. The fourth chapter will be concerned with more than one mode presenting a unifying approach to quadratic Hamiltonians including phase conjugation which is related to time reversal.

  2. Skyrmions, Spectral Flow and Parity Doubles

    E-Print Network [OSTI]

    A. P. Balachandran; S. Vaidya

    1998-03-15

    It is well-known that the winding number of the Skyrmion can be identified as the baryon number. We show in this paper that this result can also be established using the Atiyah-Singer index theorem and spectral flow arguments. We argue that this proof suggests that there are light quarks moving in the field of the Skyrmion. We then show that if these light degrees of freedom are averaged out, the low energy excitations of the Skyrmion are in fact spinorial. A natural consequence of our approach is the prediction of a $(1/2)^{-}$ state and its excitations in addition to the nucleon and delta. Using the recent numerical evidence for the existence of Skyrmions with discrete spatial symmetries, we further suggest that the the low energy spectrum of many light nuclei may possess a parity doublet structure arising from a subtle topological interaction between the slow Skyrmion and the fast quarks. We also present tentative experimental evidence supporting our arguments.

  3. On gigahertz spectral turnovers in pulsars

    E-Print Network [OSTI]

    Rajwade, Kaustubh; Anderson, Loren D

    2015-01-01

    Pulsars are known to emit non-thermal radio emission that is generally a power-law function of frequency. In some cases, a turnover is seen at frequencies around 100~MHz. Kijak et al. have reported the presence of a new class of ''Gigahertz Peaked Spectrum'' (GPS) pulsars that show spectral turnovers at frequencies around 1 GHz. We apply a model based on free-free thermal absorption to explain these turnovers in terms of surrounding material such as the dense environments found in HII regions, Pulsar Wind Nebulae (PWNe), or in cold, partially ionized molecular clouds. We show that the turnover frequency depends on the electron temperature of the environment close to the pulsar, as well as the emission measure along the line of sight. We fitted this model to the radio fluxes of known GPS pulsars and show that it can replicate the GHz turnover. From the thermal absorption model, we demonstrate that normal pulsars would exhibit a GPS-like behaviour if they were in a dense environment. We discuss the application ...

  4. Spatial Spectral Estimation forSpatial Spectral Estimation for Reactor Modeling and ControlReactor Modeling and Control

    E-Print Network [OSTI]

    Scarrott, Carl

    in Magnox nuclear reactors l Establish safe operating limits l Issues: ­ Subset of measurements ­ ControlSpatial Spectral Estimation forSpatial Spectral Estimation for Reactor Modeling and ControlReactor Modeling and Control Carl Scarrott Granville Tunnicliffe-Wilson Lancaster University, UK c

  5. Quality assurance project plan for the radionuclide airborne emissions for the Plutonium Finishing Plant

    SciTech Connect (OSTI)

    Kristofzski, J.G.; Alison, D.

    1992-04-01

    The information provided in this document meets the quality assurance (QA) requirements for the National Emission Standards for Hazardous Air Pollutants'' (NESHAP) (EPA 1989a) radionuclide airborne emissions control program in accordance with the regulation's referenced stack monitoring method (i.e. Method 114) for the Plutonium Finishing Plant (PFP). At the Hanford Site, the operations personnel have primary responsibility for implementing the continuous radionuclide emission measurements in conformance with NESHAP. Continuous measurement is used to describe continuous sampling of the effluent stream withdrawn and subjected to radiochemical analysis, and monitoring of radionuclide particulate emissions for administrative control. This Quality Assurance Project Plan (QAPjP) fully describes these PFP- implemented activities and the associated QA program as required by the NESHAP. The information is provided in the format specified in QAMS/005, Interim Guidelines and Specifications for Preparing Quality Assurance Project Plans (EPA 1983a). This QAPjP describes the QA program for only those activities that are the responsibility of the PFP: operation, calibration, and maintenance of the sampling systems. The QA requirements for laboratory services, data compilation, and data reporting are beyond the scope of this QAPjP.

  6. Quality assurance project plan for the radionuclide airborne emissions for the Plutonium Finishing Plant

    SciTech Connect (OSTI)

    Kristofzski, J.G.; Alison, D.

    1992-04-01

    The information provided in this document meets the quality assurance (QA) requirements for the ``National Emission Standards for Hazardous Air Pollutants`` (NESHAP) (EPA 1989a) radionuclide airborne emissions control program in accordance with the regulation`s referenced stack monitoring method (i.e. Method 114) for the Plutonium Finishing Plant (PFP). At the Hanford Site, the operations personnel have primary responsibility for implementing the continuous radionuclide emission measurements in conformance with NESHAP. Continuous measurement is used to describe continuous sampling of the effluent stream withdrawn and subjected to radiochemical analysis, and monitoring of radionuclide particulate emissions for administrative control. This Quality Assurance Project Plan (QAPjP) fully describes these PFP- implemented activities and the associated QA program as required by the NESHAP. The information is provided in the format specified in QAMS/005, Interim Guidelines and Specifications for Preparing Quality Assurance Project Plans (EPA 1983a). This QAPjP describes the QA program for only those activities that are the responsibility of the PFP: operation, calibration, and maintenance of the sampling systems. The QA requirements for laboratory services, data compilation, and data reporting are beyond the scope of this QAPjP.

  7. Mapping swamp timothy (Cripsis schenoides) seed productivity using spectral values and vegetation indices in managed wetlands

    SciTech Connect (OSTI)

    Rahilly, P.J.A.; Li, D.; Guo, Q.; Zhu, J.; Ortega, R.; Quinn, N.W.T.; Harmon, T.C.

    2010-01-15

    This work examines the potential to predict the seed productivity of a key wetland plant species using spectral reflectance values and spectral vegetation indices. Specifically, the seed productivity of swamp timothy (Cripsis schenoides) was investigated in two wetland ponds, managed for waterfowl habitat, in California's San Joaquin Valley. Spectral reflectance values were obtained and associated spectral vegetation indices (SVI) calculated from two sets of high resolution aerial images (May 11, 2006 and June 9, 2006) and were compared to the collected vegetation data. Vegetation data were collected and analyzed from 156 plots for total aboveground biomass, total aboveground swamp timothy biomass, and total swamp timothy seed biomass. The SVI investigated included the Simple Ratio (SR), Normalized Difference Vegetation Index (NDVI), Soil Adjusted Vegetation Index (SAVI), Transformed Soil Adjusted Vegetation Index (TSAVI), Modified Soil Adjusted Vegetation Index (MSAVI), and Global Environment Monitoring Index (GEMI). We evaluated the correlation of the various SVI with in situ vegetation measurements for linear, quadratic, exponential and power functions. In all cases, the June image provided better predictive capacity relative to May, a result that underscores the importance of timing imagery to coincide with more favorable vegetation maturity. The north pond with the June image using SR and the exponential function (R{sup 2}=0.603) proved to be the best predictor of swamp timothy seed productivity. The June image for the south pond was less predictive, with TSAVI and the exponential function providing the best correlation (R{sup 2}=0.448). This result was attributed to insufficient vegetal cover in the south pond (or a higher percentage of bare soil) due to poor drainage conditions which resulted in a delay in swamp timothy germination. The results of this work suggest that spectral reflectance can be used to estimate seed productivity in managed seasonal wetlands.

  8. The Spectra of T Dwarfs I: Near-Infrared Data and Spectral Classification

    E-Print Network [OSTI]

    Adam J. Burgasser; J. Davy Kirkpatrick; Michael E. Brown; I. Neill Reid; Adam Burrows; James Liebert; Keith Matthews; John E. Gizis; Conard C. Dahn; David G. Monet; Roc M. Cutri; Michael F. Skrutskie

    2001-08-28

    We present near-infrared spectra for a sample of T dwarfs, including eleven new discoveries made using the Two Micron All Sky Survey. These objects are distinguished from warmer (L-type) brown dwarfs by the presence of methane absorption bands in the 1--2.5 $\\micron$ spectral region. A first attempt at a near-infrared classification scheme for T dwarfs is made, based on the strengths of CH$_4$ and H$_2$O bands and the shapes of the 1.25, 1.6, and 2.1 $\\micron$ flux peaks. Subtypes T1 V through T8 V are defined, and spectral indices useful for classification are presented. The subclasses appear to follow a decreasing T$_{eff}$ scale, based on the evolution of CH$_4$ and H$_2$O bands and the properties of L and T dwarfs with known distances. However, we speculate that this scale is not linear with spectral type for cool dwarfs, due to the settling of dust layers below the photosphere and subsequent rapid evolution of spectral morphology around T$_{eff}$ $\\sim$ 1300--1500 K. Similarities in near-infrared colors and continuity of spectral features suggest that the gap between the latest L dwarfs and earliest T dwarfs has been nearly bridged. This argument is strengthened by the possible role of CH$_4$ as a minor absorber shaping the K-band spectra of the latest L dwarfs. Finally, we discuss one peculiar T dwarf, 2MASS 0937+2931, which has very blue near-infrared colors (J-K$_s$ = $-0.89\\pm$0.24) due to suppression of the 2.1 $\\micron$ peak. The feature is likely caused by enhanced collision-induced H$_2$ absorption in a high pressure or low metallicity photosphere.

  9. A GPU PARALLELIZED SPECTRAL METHOD FOR ELLIPTIC ...

    E-Print Network [OSTI]

    2013-04-29

    10 percent of them are now powered by NVIDIA Tesla GPUs (cf. [4]). Thanks to the high core density and the wide vector width SIMD architecture, using GPGPU

  10. Detailed comparisons of airborne formaldehyde measurements with box models during the 2006 INTEX-B and MILAGRO campaigns: potential evidence for significant impacts of unmeasured and multi-generation volatile organic carbon compounds

    E-Print Network [OSTI]

    2011-01-01

    Summertime ambient formaldehyde in five U.S. metropolitanin Redistributing Formaldehyde to the Upper Troposphere Overoxidation in airborne formaldehyde measurements during

  11. Compact high-quality CdSe/CdS core/shell nanocrystals with narrow emission linewidths and suppressed blinking

    E-Print Network [OSTI]

    Chen, Ou

    High particle uniformity, high photoluminescence quantum yields, narrow and symmetric emission spectral lineshapes and minimal single-dot emission intermittency (known as blinking) have been recognized as universal ...

  12. Spectral ellipsometry of a nanodiamond composite

    SciTech Connect (OSTI)

    Yastrebov, S. G. Gordeev, S. K.; Garriga, M.; Alonso, I. A.; Ivanov-Omskii, V. I.

    2006-07-15

    Optical properties of a nanodiamond composite were analyzed by methods of spectral ellipsometry in the range of photon energies 1.4-5 eV, which are characteristic of {pi}-{pi}* transitions in amorphous carbon. The nanocomposite was synthesized by molding nanodiamond powder with subsequent binding of diamond nanoparticles by pyrocarbon formed as a result of the heterogeneous chemical reaction of methane decomposition. The dispersion curves of the imaginary and real parts of the dielectric function were reconstructed. It is shown that the imaginary part of the dielectric function can be represented as the sum of two components generated by the two types of {pi}-{pi}* optical transitions. The maximum contribution of the transitions of the first and second types manifests itself at energies of 2.6 and 5.6 eV, respectively, which correspond to peaks in optical density at 2.9 and 6.11 eV. It was established that the main specific features of the normalized optical density of the nanodiamond composite almost coincide with those for poly(para-phenylenevinylene). It was found that the energy of a {sigma} + {pi} plasmon of the pyrocarbon component of the nanodiamond composite is 24.2 eV. On the basis on this value, the pyrocarbon density matrix was estimated to be 2 g/cm{sup 3}. Within the concepts of optimum filling of an elementary volume by carbon atoms in an amorphous material with such a density, the allotropic composition of the pyrocarbon matrix was restored.

  13. Spectral analysis of Kepler SPB and Beta Cep candidate stars

    E-Print Network [OSTI]

    Lehmann, H; Semaan, T; Gutiérrez, J; Smalley, B; Briquet, M; Shulyak, D; Tsymbal, V; de Cat, P

    2010-01-01

    We determine the fundamental parameters of SPB and Beta Cep candidate stars observed by the Kepler satellite mission and estimate the expected types of non-radial pulsators by comparing newly obtained high-resolution spectra with synthetic spectra computed on a grid of stellar parameters assuming LTE and check for NLTE effects for the hottest stars. For comparison, we determine Teff independently from fitting the spectral energy distribution of the stars obtained from the available photometry. We determine Teff, log(g), micro-turbulent velocity, vsin(i), metallicity, and elemental abundance for 14 of the 16 candidate stars, two of the stars are spectroscopic binaries. No significant influence of NLTE effects on the results could be found. For hot stars, we find systematic deviations of the determined effective temperatures from those given in the Kepler Input Catalogue. The deviations are confirmed by the results obtained from ground-based photometry. Five stars show reduced metallicity, two stars are He-stro...

  14. Observed Variability of the Solar Mg II h Spectral Line

    E-Print Network [OSTI]

    Schmit, Donald; De Pontieu, Bart; McIntosh, Scott; Leenaarts, Jorrit; Carlsson, Mats

    2015-01-01

    The Mg II h&k doublet are two of the primary spectral lines observed by the Sun-pointing Interface Region Imaging Spectrograph (IRIS). These lines are tracers of the magnetic and thermal environment that spans from the photosphere to the upper chromosphere. We use a double gaussian model to fit the Mg II h profile for a full-Sun mosaic dataset taken 24-Aug-2014. We use the ensemble of high-quality profile fits to conduct a statistical study on the variability of the line profile as it relates the magnetic structure, dynamics, and center-to-limb viewing angle. The average internetwork profile contains a deeply reversed core and is weakly asymmetric at h2. In the internetwork, we find a strong correlation between h3 wavelength and profile asymmetry as well h1 width and h2 width. The average reversal depth of the h3 core is inversely related to the magnetic field. Plage and sunspots exhibit many profiles which do not contain a reversal. These profiles also occur infrequently in the internetwork. We see indic...

  15. Maximum Entropy Analysis of the Spectral Functions in Lattice QCD

    E-Print Network [OSTI]

    M. Asakawa; T. Hatsuda; Y. Nakahara

    2001-02-26

    First principle calculation of the QCD spectral functions (SPFs) based on the lattice QCD simulations is reviewed. Special emphasis is placed on the Bayesian inference theory and the Maximum Entropy Method (MEM), which is a useful tool to extract SPFs from the imaginary-time correlation functions numerically obtained by the Monte Carlo method. Three important aspects of MEM are (i) it does not require a priori assumptions or parametrizations of SPFs, (ii) for given data, a unique solution is obtained if it exists, and (iii) the statistical significance of the solution can be quantitatively analyzed. The ability of MEM is explicitly demonstrated by using mock data as well as lattice QCD data. When applied to lattice data, MEM correctly reproduces the low-energy resonances and shows the existence of high-energy continuum in hadronic correlation functions. This opens up various possibilities for studying hadronic properties in QCD beyond the conventional way of analyzing the lattice data. Future problems to be studied by MEM in lattice QCD are also summarized.

  16. Spectral Formation in X-Ray Pulsar Accretion Columns

    E-Print Network [OSTI]

    Peter A. Becker; Michael T. Wolff

    2005-03-03

    We present the first self-consistent model for the dynamics and the radiative transfer occurring in bright X-ray pulsar accretion columns, with a special focus on the role of the shock in energizing the emerging X-rays. The pressure inside the accretion column of a luminous X-ray pulsar is dominated by the photons, and consequently the equations describing the coupled radiative-dynamical structure must be solved simultaneously. Spectral formation in these sources is therefore a complex, nonlinear phenomenon. We obtain the analytical solution for the Green's function describing the upscattering of monochromatic radiation injected into the column from the thermal mound located near the base of the flow. The Green's function is convolved with a Planck distribution to model the X-ray spectrum resulting from the reprocessing of blackbody photons produced in the thermal mound. These photons diffuse through the infalling gas and eventually escape out the walls of the column, forming the observed X-ray spectrum. We show that the resulting column-integrated, phase-averaged spectrum has a power-law shape at high energies and a blackbody shape at low energies, in agreement with the observational data for many X-ray pulsars.

  17. Spectral and polarization properties of photospheric emission from stratified jets

    SciTech Connect (OSTI)

    Ito, Hirotaka; Nagataki, Shigehiro; Matsumoto, Jin; Lee, Shiu-Hang; Tolstov, Alexey; Mao, Jirong; Dainotti, Maria; Mizuta, Akira

    2014-07-10

    We explore the spectral and polarization properties of photospheric emissions from stratified jets in which multiple components, separated by sharp velocity shear regions, are distributed in lateral directions. Propagation of thermal photons injected at a high optical depth region are calculated until they escape from the photosphere. It is found that the presence of the lateral structure within the jet leads to the nonthermal feature of the spectra and significant polarization signal in the resulting emission. The deviation from thermal spectra, as well as the polarization degree, tends to be enhanced as the velocity gradient in the shear region increases. In particular, we show that emissions from multicomponent jet can reproduce the typical observed spectra of gamma-ray bursts irrespective of the position of the observer when a velocity shear region is closely spaced in various lateral (?) positions. The degree of polarization associated with the emission is significant (>few percent) at a wide range of observer angles and can be higher than 30%.

  18. Indoor and Outdoor Spectroradiometer Intercomparison for Spectral Irradiance Measurement

    SciTech Connect (OSTI)

    Habte, A.; Andreas, A.; Ottoson, L.; Gueymard, C.; Fedor, G.; Fowler, S.; Peterson, J.; Naranen, R.; Kobashi, T.; Akiyama, A.; Takagi, S.

    2014-05-01

    This report details the global spectral irradiance intercomparison using spectroradiometers that was organized by the National Renewable Energy Laboratory's Solar Radiation Research Laboratory. The intercomparison was performed both indoors and outdoors on September 17, 2013. Five laboratories participated in the intercomparison using 10 spectroradiometers, and a coordinated measurement setup and a common platform were employed to compare spectral irradiances under both indoor and outdoor conditions. The intercomparison aimed to understand the performance of the different spectroradiometers and to share knowledge in making spectral irradiance measurements. This intercomparison was the first of its kind in the United States.

  19. Spectral indices in Eddington-inspired Born-Infeld inflation

    E-Print Network [OSTI]

    Inyong Cho; Jinn-Ouk Gong

    2015-06-23

    We investigate the scalar and the tensor spectral indices of the quadratic inflation model in Eddington-inspired Born-Infeld (EiBI) gravity. We find the EiBI corrections to the spectral indices are of second and first order in the slow-roll approximation for the scalar and the tensor perturbations respectively. This is very promising since the quadratic inflation model in general relativity provides a very nice fit for the spectral indices. Together with the suppression of the tensor-to-scalar ratio EiBI inflation is well along with the observational data.

  20. IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 20, NO. 6, NOVEMBER 2005 1499 Custom Spectral Shaping for EMI Reduction in

    E-Print Network [OSTI]

    IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 20, NO. 6, NOVEMBER 2005 1499 Custom Spectral Shaping), electronic ballast, frequency modulation (FM), resonant inverter, spread spectrum. I. INTRODUCTION HIGH-FREQUENCY (HF) ac sources are used in a va- riety of applications, including electronic ballasts where HF

  1. SPECTRAL SLOPE VARIATION AT PROTON SCALES FROM FAST TO SLOW SOLAR WIND

    SciTech Connect (OSTI)

    Bruno, R.; Trenchi, L.; Telloni, D.

    2014-09-20

    We investigated the behavior of the spectral slope of interplanetary magnetic field fluctuations at proton scales for selected high-resolution time intervals from the WIND and MESSENGER spacecraft at 1 AU and 0.56 AU, respectively. The analysis was performed within the profile of high-speed streams, moving from fast to slow wind regions. The spectral slope showed a large variability between –3.75 and –1.75 and a robust tendency for this parameter to be steeper within the trailing edge, where the speed is higher, and to be flatter within the subsequent slower wind, following a gradual transition between these two states. The value of the spectral index seems to depend firmly on the power associated with the fluctuations within the inertial range; the higher the power, the steeper the slope. Our results support previous analyses suggesting that there must be some response of the dissipation mechanism to the level of the energy transfer rate along the inertial range.

  2. Analysis of hyper-spectral data derived from an imaging Fourier transform: A statistical perspective

    SciTech Connect (OSTI)

    Sengupta, S.K.; Clark, G.A.; Fields, D.J.

    1996-01-10

    Fourier transform spectrometers (FTS) using optical sensors are increasingly being used in various branches of science. Typically, a FTS generates a three-dimensional data cube with two spatial dimensions and one frequency/wavelength dimension. The number of frequency dimensions in such data cubes is generally very large, often in the hundreds, making data analytical procedures extremely complex. In the present report, the problem is viewed from a statistical perspective. A set of procedures based on the high degree of inter-channel correlation structure often present in such hyper-spectral data, has been identified and applied to an example data set of dimension 100 x 128 x 128 comprising 128 spectral bands. It is shown that in this case, the special eigen-structure of the correlation matrix has allowed the authors to extract just a few linear combinations of the channels (the significant principal vectors) that effectively contain almost all of the spectral information contained in the data set analyzed. This in turn, enables them to segment the objects in the given spatial frame using, in a parsimonious yet highly effective way, most of the information contained in the data set.

  3. Spectral characteristics of Mrk 501 during the 2012 and 2014 flaring states

    E-Print Network [OSTI]

    Cologna, Gabriele; Mohamed, Mahmoud; Rieger, Frank; Romoli, Carlo; Taylor, Andrew; Wagner, Stefan J; Wierzcholska, Alicja; Jacholkowska, Agnieszka; Kurtanidze, Omar

    2015-01-01

    Observations at Very High Energies (VHE, E > 100 GeV) of the BL Lac object Mrk 501 taken with the High Energy Stereoscopic System (H.E.S.S.) in four distinct periods between 2004 and 2014 are presented, with focus on the 2012 and 2014 flaring states. The source is detected with high significance above $\\sim$ 2 TeV in $\\sim$ 13.1 h livetime. The observations comprise low flux states and strong flaring events, which in 2014 show a flux level comparable to the 1997 historical maximum. Such high flux states enable spectral variability and flux variability studies down to a timescale of four minutes in the 2-20 TeV energy range. During the 2014 flare, the source is clearly detected in each of these bins. The intrinsic spectrum is well described by a power law of index $\\Gamma=2.15\\pm0.06$ and does not show curvature in this energy range. Flux dependent spectral analyses show a clear harder-when-brighter behaviour. The high flux levels and the high sensitivity of H.E.S.S. allow studies in the unprecedented combinat...

  4. Spectral SP: A New Approach to Mapping Reservoir Flow and Permeability...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Spectral SP: A New Approach to Mapping Reservoir Flow and Permeability Spectral SP: A New Approach to Mapping Reservoir Flow and Permeability Spectral SP: A New Approach to Mapping...

  5. Development of the Ultrashort Pulse Nonlinear Optical Microscopy Spectral Imaging System 

    E-Print Network [OSTI]

    Lee, Anthony Chien-der

    2012-10-19

    by broadband sub-10-fs pulses. This dissertation will discuss the development of two spectral imaging systems using the principles of nonlinear optical microscopy for pixel-by-pixel spectral segmentation of multiple fluorescent spectra. The first spectral...

  6. A new hybrid spectral similarity measure for discrimination of Vigna species

    E-Print Network [OSTI]

    Kumar, M Naresh; Prasad, K S Vara; Kamala, V; Ramana, K V; Dwivedi, R S; Roy, P S

    2015-01-01

    The reflectance spectrum of the species in a hyperspectral data can be modelled as an n-dimensional vector. The spectral angle mapper computes the angle between the vectors which is used to discriminate the species. The spectral information divergence models the data as a probability distribution so that the spectral variability between the bands can be extracted using the stochastic measures. The hybrid approach of spectral angle mapper and spectral information divergence is found to be better discriminator than spectral angle mapper or spectral information divergence alone. The spectral correlation angle is computed as a cosine of the angle of the Pearsonian correlation coefficient between the vectors. The spectral correlation angle is a better measure than the spectral angle mapper as it considers only standardized values of the vectors rather than the absolute values of the vector. In the present paper a new hybrid measure is proposed which is based on the spectral correlation angle and the spectral infor...

  7. Monotonically convergent optimal control theory of quantum systems with spectral constraints on the control field

    E-Print Network [OSTI]

    M. Lapert; R. Tehini; G. Turinici; D. Sugny

    2009-06-05

    We propose a new monotonically convergent algorithm which can enforce spectral constraints on the control field (and extends to arbitrary filters). The procedure differs from standard algorithms in that at each iteration the control field is taken as a linear combination of the control field (computed by the standard algorithm) and the filtered field. The parameter of the linear combination is chosen to respect the monotonic behavior of the algorithm and to be as close to the filtered field as possible. We test the efficiency of this method on molecular alignment. Using band-pass filters, we show how to select particular rotational transitions to reach high alignment efficiency. We also consider spectral constraints corresponding to experimental conditions using pulse shaping techniques. We determine an optimal solution that could be implemented experimentally with this technique.

  8. Spectral Lags of Gamma-Ray Bursts from Primordial Black Hole (PBH) Evaporations

    E-Print Network [OSTI]

    T. N. Ukwatta; J. H. MacGibbon; W. C. Parke; K. S. Dhuga; A. Eskandarian; N. Gehrels; L. Maximon; D. C. Morris

    2009-08-14

    Primordial Black Holes (PBHs), which may have been created in the early Universe, are predicted to be detectable by their Hawking radiation. PBHs with an initial mass of 5.0 * 10^14 g should be expiring today with a burst of high energy particles. Evaporating PBHs in the solar neighborhood are candidate Gamma-Ray Bursts (GRBs) progenitors. We propose spectral lag, which is the temporal delay between the high energy photon pulse and the low energy photon pulse, as a possible method to detect PBH evaporation events with the Fermi Gamma-ray Space Telescope Observatory.

  9. Unified Accretion Disk Models Around Black Holes and Neutron Stars and Their Spectral Properties

    E-Print Network [OSTI]

    Sandip K. Chakrabarti

    1996-11-10

    We review the current understanding of accretion flows around compact objects with a special emphasis on advective disks. We discuss the influence of the centrifugal pressure supported high density region around compact objects (where shocks may also form) on the emitted spectra. We show that the stationary and non-stationary spectral properties (such as, low and high states, transition of states, quasi-periodic oscillations, quiescent and rising phases of X-ray novae, etc.) of both low mass and supermassive black hole candidates could be satisfactorily explained within the framework of the analytical solution of the advective disks without invoking any ad hoc components such as Compton clouds or magnetic corona.

  10. Accurate atmospheric parameters at moderate resolution using spectral indices: Preliminary application to the marvels survey

    SciTech Connect (OSTI)

    Ghezzi, Luan; Da Costa, Luiz N.; Maia, Marcio A. G.; Ogando, Ricardo L. C.; Dutra-Ferreira, Letícia; Lorenzo-Oliveira, Diego; Porto de Mello, Gustavo F.; Santiago, Basílio X.; De Lee, Nathan; Lee, Brian L.; Ge, Jian; Wisniewski, John P.; González Hernández, Jonay I.; Stassun, Keivan G.; Cargile, Phillip; Pepper, Joshua; Fleming, Scott W.; Schneider, Donald P.; Mahadevan, Suvrath; Wang, Ji; and others

    2014-12-01

    Studies of Galactic chemical, and dynamical evolution in the solar neighborhood depend on the availability of precise atmospheric parameters (effective temperature T {sub eff}, metallicity [Fe/H], and surface gravity log g) for solar-type stars. Many large-scale spectroscopic surveys operate at low to moderate spectral resolution for efficiency in observing large samples, which makes the stellar characterization difficult due to the high degree of blending of spectral features. Therefore, most surveys employ spectral synthesis, which is a powerful technique, but relies heavily on the completeness and accuracy of atomic line databases and can yield possibly correlated atmospheric parameters. In this work, we use an alternative method based on spectral indices to determine the atmospheric parameters of a sample of nearby FGK dwarfs and subgiants observed by the MARVELS survey at moderate resolving power (R ? 12,000). To avoid a time-consuming manual analysis, we have developed three codes to automatically normalize the observed spectra, measure the equivalent widths of the indices, and, through a comparison of those with values calculated with predetermined calibrations, estimate the atmospheric parameters of the stars. The calibrations were derived using a sample of 309 stars with precise stellar parameters obtained from the analysis of high-resolution FEROS spectra, permitting the low-resolution equivalent widths to be directly related to the stellar parameters. A validation test of the method was conducted with a sample of 30 MARVELS targets that also have reliable atmospheric parameters derived from the high-resolution spectra and spectroscopic analysis based on the excitation and ionization equilibria method. Our approach was able to recover the parameters within 80 K for T {sub eff}, 0.05 dex for [Fe/H], and 0.15 dex for log g, values that are lower than or equal to the typical external uncertainties found between different high-resolution analyses. An additional test was performed with a subsample of 138 stars from the ELODIE stellar library, and the literature atmospheric parameters were recovered within 125 K for T {sub eff}, 0.10 dex for [Fe/H], and 0.29 dex for log g. These precisions are consistent with or better than those provided by the pipelines of surveys operating with similar resolutions. These results show that the spectral indices are a competitive tool to characterize stars with intermediate resolution spectra.

  11. Direct Experimental Determination of Spectral Densities of Molecular Complexes

    E-Print Network [OSTI]

    Leonardo A. Pachon; Paul Brumer

    2014-10-15

    Determining the spectral density of a molecular system immersed in a proteomic scaffold and in contact to a solvent is a fundamental challenge in the coarse-grained description of, e.g., electron and energy transfer dynamics. Once the spectral density is characterized, all the time scales are captured and no artificial separation between fast and slow processes need be invoked. Based on the fluorescence Stokes shift function, we utilize a simple and robust strategy to extract the spectral density of a number of molecular complexes from available experimental data. Specifically, we show that experimental data for dye molecules in several solvents, amino acid proteins in water, and some photochemical systems (e.g., rhodopsin and green fluorescence proteins), are well described by a three-parameter family of sub-Ohmic spectral densities that are characterized by a fast initial Gaussian-like decay followed by a slow algebraic-like decay rate at long times.

  12. Goodwillie calculus and algebras over a spectral operad

    E-Print Network [OSTI]

    Pereira, Luis Alexandre Meira Fernandes Alves

    2013-01-01

    The overall goal of this thesis is to apply the theory of Goodwillie calculus to the category Algo of algebras over a spectral operad. Its first part generalizes many of the original results of Goodwillie in [14] so that ...

  13. Direct experimental determination of spectral densities of molecular complexes

    SciTech Connect (OSTI)

    Pachón, Leonardo A.; Brumer, Paul

    2014-11-07

    Determining the spectral density of a molecular system immersed in a proteomic scaffold and in contact to a solvent is a fundamental challenge in the coarse-grained description of, e.g., electron and energy transfer dynamics. Once the spectral density is characterized, all the time scales are captured and no artificial separation between fast and slow processes need to be invoked. Based on the fluorescence Stokes shift function, we utilize a simple and robust strategy to extract the spectral density of a number of molecular complexes from available experimental data. Specifically, we show that experimental data for dye molecules in several solvents, amino acid proteins in water, and some photochemical systems (e.g., rhodopsin and green fluorescence proteins), are well described by a three-parameter family of sub-Ohmic spectral densities that are characterized by a fast initial Gaussian-like decay followed by a slow algebraic-like decay rate at long times.

  14. Spectral Clustering Gene Ontology Terms to Group Genes by Function

    E-Print Network [OSTI]

    Zell, Andreas

    Spectral Clustering Gene Ontology Terms to Group Genes by Function Nora Speer, Christian Spieth­12, 2005. c Springer-Verlag Berlin Heidelberg 2005 #12;2 N. Speer, C. Spieth, and A. Zell part-of is-a GO

  15. Moments of $?$ meson spectral functions in vacuum and nuclear matter

    E-Print Network [OSTI]

    Philipp Gubler; Wolfram Weise

    2015-07-14

    Moments of the $\\phi$ meson spectral function in vacuum and in nuclear matter are analyzed, combining a model based on chiral SU(3) effective field theory (with kaonic degrees of freedom) and finite-energy QCD sum rules. For the vacuum we show that the spectral density is strongly constrained by a recent accurate measurement of the $e^+ e^- \\to K^+ K^-$ cross section. In nuclear matter the $\\phi$ spectrum is modified by interactions of the decay kaons with the surrounding nuclear medium, leading to a significant broadening and an asymmetric deformation of the $\\phi$ meson peak. We demonstrate that both in vacuum and nuclear matter, the first two moments of the spectral function are compatible with finite-energy QCD sum rules. A brief discussion of the next-higher spectral moment involving strange four-quark condensates is also presented.

  16. An improved spectral graph partitioning algorithm for mapping parallel computations

    SciTech Connect (OSTI)

    Hendrickson, B.; Leland, R.

    1992-09-01

    Efficient use of a distributed memory parallel computer requires that the computational load be balanced across processors in a way that minimizes interprocessor communication. We present a new domain mapping algorithm that extends recent work in which ideas from spectral graph theory have been applied to this problem. Our generalization of spectral graph bisection involves a novel use of multiple eigenvectors to allow for division of a computation into four or eight parts at each stage of a recursive decomposition. The resulting method is suitable for scientific computations like irregular finite elements or differences performed on hypercube or mesh architecture machines. Experimental results confirm that the new method provides better decompositions arrived at more economically and robustly than with previous spectral methods. We have also improved upon the known spectral lower bound for graph bisection.

  17. Efficient Spectral-Galerkin Method and Analysis for Elliptic PDEs ...

    E-Print Network [OSTI]

    2015-11-22

    ... use the coercivity of the bilinear form and polynomial approximation theory to derive ...... Ammari, H., Bao, G., Wood, A.W.: Analysis of the electromagnetic scattering ... Quarteroni, A., Zang, T.A.: Spectral Methods: Fundamentals in Single Do-.

  18. APPROXIMATING SPECTRAL INVARIANTS OF HARPER OPERATORS ON GRAPHS II

    E-Print Network [OSTI]

    Schick, Thomas

    APPROXIMATING SPECTRAL INVARIANTS OF HARPER OPERATORS ON GRAPHS II VARGHESE MATHAI, THOMAS SCHICK;2 VARGHESE MATHAI, THOMAS SCHICK, AND STUART YATES subset E+ of these edges in which each combinatorial edge

  19. A Spectral-Scanning Magnetic Resonance Imaging (MRI) Integrated System

    E-Print Network [OSTI]

    Hajimiri, Ali

    , detection time, spectral resolution, and the spatial resolution (relative to the sample size) equivalent that the electromotive force (emf) voltage induced in the coils of the MR system, )(tE , is describe by [ ] -= V n d

  20. COLLOQUIUM: Seismic Imaging and Inversion Based on Spectral-Element...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    February 6, 2013, 4:15pm to 5:30pm Colloquia MBG Auditorium COLLOQUIUM: Seismic Imaging and Inversion Based on Spectral-Element and Adjoint Methods Professor Jeroen Tromp Princeton...

  1. Real-Time Airborne Gamma-Ray Background Estimation Using NASVD with MLE and Radiation Transport for Calibration

    SciTech Connect (OSTI)

    Kulisek, Jonathan A.; Schweppe, John E.; Stave, Sean C.; Bernacki, Bruce E.; Jordan, David V.; Stewart, Trevor N.; Seifert, Carolyn E.; Kernan, Warnick J.

    2015-06-01

    Helicopter-mounted gamma-ray detectors can provide law enforcement officials the means to quickly and accurately detect, identify, and locate radiological threats over a wide geographical area. The ability to accurately distinguish radiological threat-generated gamma-ray signatures from background gamma radiation in real time is essential in order to realize this potential. This problem is non-trivial, especially in urban environments for which the background may change very rapidly during flight. This exacerbates the challenge of estimating background due to the poor counting statistics inherent in real-time airborne gamma-ray spectroscopy measurements. To address this, we have developed a new technique for real-time estimation of background gamma radiation from aerial measurements. This method is built upon on the noise-adjusted singular value decomposition (NASVD) technique that was previously developed for estimating the potassium (K), uranium (U), and thorium (T) concentrations in soil post-flight. The method can be calibrated using K, U, and T spectra determined from radiation transport simulations along with basis functions, which may be determined empirically by applying maximum likelihood estimation (MLE) to previously measured airborne gamma-ray spectra. The method was applied to both measured and simulated airborne gamma-ray spectra, with and without man-made radiological source injections. Compared to schemes based on simple averaging, this technique was less sensitive to background contamination from the injected man-made sources and may be particularly useful when the gamma-ray background frequently changes during the course of the flight.

  2. Spectral analysis of a class of Schroedinger operators exhibiting a parameter-dependent spectral transition

    E-Print Network [OSTI]

    Diana Barseghyan; Pavel Exner; Andrii Khrabustovskyi; Milos Tater

    2015-10-31

    We analyze two-dimensional Schr\\"odinger operators with the potential $|xy|^p - \\lambda (x^2+y^2)^{p/(p+2)}$ where $p\\ge 1$ and $\\lambda\\ge 0$, which exhibit an abrupt change of its spectral properties at a critical value of the coupling constant $\\lambda$. We show that in the supercritical case the spectrum covers the whole real axis. In contrast, for $\\lambda$ below the critical value the spectrum is purely discrete and we establish a Lieb-Thirring-type bound on its moments. In the critical case the essential spectrum covers the positive halfline while the negative spectrum can be only discrete, we demonstrate numerically the existence of a ground state eigenvalue.

  3. Assessment of Unabated Facility Emission Potentials for Evaluating Airborne Radionuclide Monitoring Requirements at Pacific Northwest National Laboratory - 2007

    SciTech Connect (OSTI)

    Ballinger, Marcel Y.; Barfuss, Brad C.; Gervais, Todd L.

    2008-01-01

    Assessments were performed to evaluate compliance with the airborne radionuclide emission monitoring requirements in the National Emission Standards for Hazardous Air Pollutants (NESHAP – U.S. Code of Federal Regulations, Title 40, Part 61, Subpart H) and Washington Administrative Code (WAC) 246-247: Radiation Protection – Air Emissions. In these NESHAP assessments, potential unabated offsite doses were evaluated for emission locations at buildings that are part of the consolidated laboratory campus of the Pacific Northwest National Laboratory. This report describes the inventory-based methods and provides the results for the NESHAP assessment performed in 2007.

  4. Assessment of Unabated Facility Emission Potentials for Evaluating Airborne Radionuclide Monitoring Requirements at Pacific Northwest National Laboratory - 2001

    SciTech Connect (OSTI)

    Ballinger, Marcel Y.; Sula, Monte J.; Gervais, Todd L.; Shields, Keith D.; Edwards, Daniel R.

    2001-09-28

    Assessments were performed to evaluate compliance with the airborne radionuclide emission monitoring requirements in the National Emission Standards for Hazardous Air Pollutants (NESHAP - U.S. Code of Federal Regulations, Title 40 Part 61, Subpart H) and Washington Administrative Code (WAC) 246-247: Radiation Protection - Air Emissions. In these assessments, potential unabated offsite doses were evaluated for emission locations at facilities owned by the U.S. Department of Energy and operated by Pacific Northwest National Laboratory (PNNL) on the Hanford Site. This report describes the inventory-based methods, and provides the results, for the assessment performed in 2001.

  5. Assessment of Unabated Facility Emission Potentials for Evaluating Airborne Radionuclide Monitoring Requirements at Pacific Northwest National Laboratory - 2003

    SciTech Connect (OSTI)

    Ballinger, Marcel Y.; Sula, Monte J.; Gervais, Todd L.; Edwards, Daniel L.

    2003-12-05

    Assessments were performed to evaluate compliance with the airborne radionuclide emission monitoring requirements in the National Emission Standards for Hazardous Air Pollutants (NESHAP - U.S. Code of Federal Regulations, Title 40, Part 61, Subpart H) and Washington Administrative Code (WAC) 246-247: Radiation Protection - Air Emissions. In these assessments, potential unabated offsite doses were evaluated for emission locations at facilities owned by the U.S. Department of Energy and operated by Pacific Northwest National Laboratory (PNNL) on the Hanford Site. This report describes the inventory-based methods and provides the results for the assessment performed in 2003.

  6. Assessment of Unabated Facility Emission Potentials for Evaluating Airborne Radionuclide Monitoring Requirements at Pacific Northwest National Laboratory - 2010

    SciTech Connect (OSTI)

    Ballinger, Marcel Y.; Gervais, Todd L.; Barnett, J. M.

    2011-05-13

    Assessments were performed to evaluate compliance with the airborne radionuclide emission monitoring requirements in the National Emission Standards for Hazardous Air Pollutants ([NESHAP]; U.S. Code of Federal Regulations, Title 40, Part 61, Subpart H) and Washington Administrative Code 246-247: Radiation Protection - Air Emissions. In these NESHAP assessments, potential unabated off-site doses were evaluated for emission locations at buildings that are part of the consolidated laboratory campus of the Pacific Northwest National Laboratory. This report describes the inventory-based methods and provides the results for the NESHAP assessment performed in 2010.

  7. Spectral sensitization of nanocrystalline solar cells

    DOE Patents [OSTI]

    Spitler, Mark T. (Concord, MA); Ehret, Anne (Malden, MA); Stuhl, Louis S. (Bedford, MA)

    2002-01-01

    This invention relates to dye sensitized polycrystalline photoelectrochemical solar cells for use in energy transduction from light to electricity. It concerns the utility of highly absorbing organic chromophores as sensitizers in such cells and the degree to which they may be utilized alone and in combination to produce an efficient photoelectrochemical cell, e.g., a regenerative solar cell.

  8. Magnetorefractive effect in manganites with a colossal magnetoresistance in the visible spectral region

    SciTech Connect (OSTI)

    Sukhorukov, Yu. P., E-mail: suhorukov@imp.uran.ru; Telegin, A. V. [Russian Academy of Sciences, Institute of Metal Physics, Ural Branch (Russian Federation); Granovsky, A. B., E-mail: granov@magn.ru; Gan'shina, E. A. [Moscow State University, Faculty of Physics (Russian Federation); Zhukov, A.; Gonzalez, J. [Universidad del Pais Vasco (UPV)/Euskal Herriko Unibertsitatea (EHU), Departamento de Fisica de Materiales, Facultad de Quimica (Spain); Herranz, G. [Institut de Ciencia de Materials de Barcelona (ICMAB)-CSIC (Spain); Caicedo, J. M. [Universidad del Pais Vasco (UPV)/Euskal Herriko Unibertsitatea (EHU), Departamento de Fisica de Materiales, Facultad de Quimica (Spain); Yurasov, A. N. [Moscow State Institute of Radio-Engineering, Electronics, and Automation (Technical University) (Russian Federation); Bessonov, V. D. [Russian Academy of Sciences, Institute of Metal Physics, Ural Branch (Russian Federation); Kaul', A. R.; Gorbenko, O. Yu.; Korsakov, I. E. [Moscow State University, Faculty of Physics (Russian Federation)

    2012-01-15

    The magnetotransmission, magnetoreflection, and magnetoresistance of the La{sub 0.7}Ca{sub 0.3}MnO{sub 3} and La{sub 0.9}Ag{sub 0.1}MnO{sub 3} epitaxial films have been investigated. It has been found that the films exhibit a significant magnetorefractive effect in the case of reflection and transmission of light in the fundamental absorption region both in the vicinity of the Curie temperature and at low temperatures. It has been shown that the magnetorefractive effect in the infrared spectral region of the manganites is determined by a high-frequency response to magnetoresistance, whereas the magnetorefractive effect in the visible spectral region of these materials is associated with a change in the electronic structure in response to a magnetic field, which, in turn, leads to a change in the electron density of states, the probability of interband optical transitions, and the shift of light absorption bands. The obtained values of the magnetotransmittance and magnetoreflectance in the visible spectral region are less than those observed in the infrared region of the spectrum, but they are several times greater than the linear magneto-optical effects. As a result, the magnetorefractive effect, which is a nongyrotropic phenomenon, makes it possible to avoid the use of light analyzers and polarizers in optical circuits.

  9. Statistical properties of multi-epoch spectral variability of SDSS stripe 82 quasars

    SciTech Connect (OSTI)

    Kokubo, Mitsuru; Morokuma, Tomoki; Minezaki, Takeo; Doi, Mamoru [Institute of Astronomy, School of Science, University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo 181-0015 (Japan); Kawaguchi, Toshihiro [Department of Physics and Information Science, Yamaguchi University, Yamaguchi, Yamaguchi 753-8512 (Japan); Sameshima, Hiroaki [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Sagamihara, Kanagawa 252-5210 (Japan); Koshida, Shintaro, E-mail: mkokubo@ioa.s.u-tokyo.ac.jp [Center of Astro Engineering and Department of Electrical Engineering, Pontificia Universidad Catolica de Chile, Av. Vicuña Mackenna 4860, Santiago (Chile)

    2014-03-01

    We investigate the UV-optical (longward of Ly? 1216 Å) spectral variability of nearly 9000 quasars (0 < z < 4) using multi-epoch photometric data within the SDSS Stripe 82 region. The regression slope in the flux-flux space of a quasar light curve directly measures the color of the flux difference spectrum, then the spectral shape of the flux difference spectra can be derived by taking a careful look at the redshift dependence of the regression slopes. First, we confirm that the observed quasar spectrum becomes bluer when the quasar becomes brighter. We infer the spectral index of the composite difference spectrum as ?{sub ?}{sup dif}?+1/3 (in the form of f{sub ?}??{sup ?{sub ?}}), which is significantly bluer than that of the composite spectrum ?{sub ?}{sup com}??0.5. We also show that the continuum variability cannot be explained by accretion disk models with varying mass accretion rates. Second, we examine the effects of broad emission line variability on the color-redshift space. The variability of the 'Small Blue Bump' is extensively discussed. We show that the low-ionization lines of Mg II and Fe II are less variable compared to Balmer emission lines and high-ionization lines, and the Balmer continuum is the dominant variable source around ?3000 Å. These results are compared with previous studies, and the physical mechanisms of the variability of the continuum and emission lines are discussed.

  10. Nonlinear Legendre Spectral Finite Elements for Wind Turbine Blade Dynamics: Preprint

    SciTech Connect (OSTI)

    Wang, Q.; Sprague, M. A.; Jonkman, J.; Johnson, N.

    2014-01-01

    This paper presents a numerical implementation and examination of new wind turbine blade finite element model based on Geometrically Exact Beam Theory (GEBT) and a high-order spectral finite element method. The displacement-based GEBT is presented, which includes the coupling effects that exist in composite structures and geometric nonlinearity. Legendre spectral finite elements (LSFEs) are high-order finite elements with nodes located at the Gauss-Legendre-Lobatto points. LSFEs can be an order of magnitude more efficient that low-order finite elements for a given accuracy level. Interpolation of the three-dimensional rotation, a major technical barrier in large-deformation simulation, is discussed in the context of LSFEs. It is shown, by numerical example, that the high-order LSFEs, where weak forms are evaluated with nodal quadrature, do not suffer from a drawback that exists in low-order finite elements where the tangent-stiffness matrix is calculated at the Gauss points. Finally, the new LSFE code is implemented in the new FAST Modularization Framework for dynamic simulation of highly flexible composite-material wind turbine blades. The framework allows for fully interactive simulations of turbine blades in operating conditions. Numerical examples showing validation and LSFE performance will be provided in the final paper.

  11. Spectral properties of electrons in fractal nanowires

    E-Print Network [OSTI]

    Alberto Hernando; Miroslav Sulc; Jiri Vanicek

    2015-03-26

    In view of promising applications of fractal nanostructures, we analyze the spectra of quantum particles in the Sierpinski carpet and study the non-correlated electron gas in this geometry. We show that the spectrum exhibits scale invariance with almost arbitrary spacing between energy levels, including large energy gaps at high energies. These features disappear in the analogous random fractal---where Anderson localization dominates---and in the regular lattice of equally sized holes---where only two length scales are present. The fractal structure amplifies microscopic effects, resulting in the presence of quantum behavior of the electron gas even at high temperatures. Our results demonstrate the potential of fractal nanostructures to improve the light-matter interaction at any frequency, with possible applications, e.g., in the development of solar cells with a wide absorption spectrum, artificial photosynthesis, or nanometamaterials with tailored Fermi levels and band gaps, operating in a wide range of frequencies, and with extended operating temperature range.

  12. Spectral problems in open quantum chaos

    E-Print Network [OSTI]

    Stéphane Nonnenmacher

    2011-11-03

    This review article will present some recent results and methods in the study of 1-particle quantum or wave scattering systems, in the semiclassical/high frequency limit, in cases where the corresponding classical/ray dynamics is chaotic. We will focus on the distribution of quantum resonances, and the structure of the corresponding metastable states. Our study includes the toy model of open quantum maps, as well as the recent quantum monodromy operator method.

  13. Spectral problems in open quantum chaos

    E-Print Network [OSTI]

    Nonnenmacher, Stéphane

    2011-01-01

    This review article will present some recent results and methods in the study of 1-particle quantum or wave scattering systems, in the semiclassical/high frequency limit, in cases where the corresponding classical/ray dynamics is chaotic. We will focus on the distribution of quantum resonances, and the structure of the corresponding metastable states. Our study includes the toy model of open quantum maps, as well as the recent quantum monodromy operator method.

  14. Profiled spectral lines generated in the field of Kerr superspinars

    SciTech Connect (OSTI)

    Schee, Jan; Stuchlík, Zdenek E-mail: zdenek.stuchlik@fpf.slu.cz

    2013-04-01

    String Theory suggests existence of primordial Kerr superspinars, extremely compact objects with external spacetime described by the Kerr naked singularity geometry. The primordial Kerr superspinars have to be converted to a near-extreme black hole due to accretion, but they could survive to the era of highly redshifted quasars. We study the shape of the profiled spectral lines generated by radiating rings or the innermost parts of Keplerian discs orbiting the Kerr superspinars. Influence of the superspinar surface location on the profiled lines is also considered. We demonstrate strong difference of the character of the profiled lines generated by radiating rings for all values of the superspinar spin and all values of the inclination angles of the observer when compared to those generated in the field of Kerr black holes. For small and mediate inclination angles there are large quantitative differences in the extension and position of the lines. For large inclination angles even strong qualitative difference appears as the profiled lines have a clear doubled character. The smaller, redshifted region of the profiled line is related to the photons reaching the regions near the superspinar surface. Strong differences are obtained also for profiled lines generated by the innermost parts of Keplerian discs especially in the shape of the line. The influence of the superspinar surface location is reflected in the intermediate parts of the the profiled lines. The line profiles can give a clear signature of the presence of a Kerr superspinar and in principle enable estimates of its surface location since the signatures of the superspinar surface location are of different character as those corresponding to the presence of the black hole horizon.

  15. Atlas of Atomic Spectral Lines of Neptunium Emitted by Inductively Coupled Plasma

    SciTech Connect (OSTI)

    DeKalb, E.L. and Edelson, M. C.

    1987-08-01

    Optical emission spectra from high-purity Np-237 were generated with a glovebox-enclosed inductively coupled plasma (ICP) source. Spectra covering the 230-700 nm wavelength range are presented along with general commentary on the methodology used in collecting the data. The Ames Laboratory Nuclear Safeguards and Security Program has been charged with the task of developing optical spectroscopic methods to analyze the composition of spent nuclear fuels. Such materials are highly radioactive even after prolonged 'cooling' and are chemically complex. Neptunium (Np) is a highly toxic by-product of nuclear power generation and is found, in low abundance, in spent nuclear fuels. This atlas of the optical emission spectrum of Np, as produced by an inductively coupled plasma (ICP) spectroscopic source, is part of a general survey of the ICP emission spectra of the actinide elements. The ICP emission spectrum of the actinides originates almost exclusively from the electronic relaxation of excited, singly ionized species. Spectral data on the Np ion emission spectrum (i.e., the Np II spectrum) have been reported by Tomkins and Fred [1] and Haaland [2]. Tomkins and Fred excited the Np II spectrum with a Cu spark discharge and identified 114 Np lines in the 265.5 - 436.3 nm spectral range. Haaland, who corrected some spectral line misidentifications in the work of Tomkins and Fred, utilized an enclosed Au spark discharge to excite the Np II spectrum and reported 203 Np lines within the 265.4 - 461.0 nm wavelength range.

  16. Resolution of the spectral technique in kinetic modeling

    SciTech Connect (OSTI)

    Kuo, Chaincy; Reutter, Bryan W.; Huesman, Ronald H.

    2001-02-17

    Physiologic systems can be represented by compartmental models which describe the uptake of radio-labeled tracers from blood to tissue and their subsequent washout. Arterial and venous time-activity curves from isolated heart experiments are analyzed using spectral analysis, in which the impulse response function is represented by a sum of decaying exponentials. Resolution and uniqueness tests are conducted by synthesizing isolated heart data with predefined compartmental models, adding noise, and applying the spectral analysis technique. Venous time-activity curves are generated by convolving a typical arterial input function with the predefined spectrum. The coefficients of a set of decaying exponential basis functions are determined using a non-negative least squares algorithm, and results are compared with the predefined spectrum. The uniqueness of spectral method solutions is investigated by computing model covariance matrices, using error propagation and prior knowledge of noise distributions. Coupling between model parameters is illustrated with correlation matrices.

  17. Spectral characterization of a frequency comb based on cascaded quadratic nonlinearities inside an optical parametric oscillator

    E-Print Network [OSTI]

    Ulvila, Ville; Halonen, Lauri; Vainio, Markku

    2015-01-01

    We present an experimental study of optical frequency comb generation based on cascaded quadratic nonlinearities inside a continuous-wave-pumped optical parametric oscillator. We demonstrate comb states which produce narrow-linewidth intermode beat note signals, and we verify the mode spacing uniformity of the comb at the Hz level. We also show that spectral quality of the comb can be improved by modulating the parametric gain at a frequency that corresponds to the comb mode spacing. We have reached a high average output power of over 4 W in the near-infrared region, at ~2 {\\mu}m.

  18. Scattering of an ultrashort electromagnetic radiation pulse by an atom in a broad spectral range

    SciTech Connect (OSTI)

    Astapenko, V. A., E-mail: astval@mail.ru [Moscow Institute of Physics and Technology (Russian Federation)

    2011-02-15

    The scattering of an ultrashort electromagnetic pulse by atomic particles is described using a consistent quantum-mechanical approach taking into account excitation of a target and nondipole electromagnetic interaction, which is valid in a broad spectral range. This approach is applied to the scattering of single- and few-cycle pulses by a multielectron atom and a hydrogen atom. Scattering spectra are obtained for ultrashort pulses of different durations. The relative contribution of 'elastic' scattering of a single-cycle pulse by a hydrogen atom is studied in the high-frequency limit as a function of the carrier frequency and scattering angle.

  19. The Flight Spectral Response of the ACIS Instrument

    E-Print Network [OSTI]

    Paul P. Plucinsky; Norbert S. Schulz; Herman L. Marshall; Catherine E. Grant; George Chartas; Divas Sanwal; Marcus A. Teter; Alexey A. Vikhlinin; Richard J. Edgar; Michael W. Wise; Glenn E. Allen; Shanil N. Virani; Joseph M. DePasquale; Michael T. Raley

    2002-09-24

    We discuss the flight calibration of the spectral response of the Advanced CCD Imaging Spectrometer (ACIS) on-board the Chandra X-ray Observatory (CXO). The spectral resolution and sensitivity of the ACIS instrument have both been evolving over the course of the mission. The spectral resolution of the frontside-illuminated (FI) CCDs changed dramatically in the first month of the mission due to radiation damage. Since that time, the spectral resolution of the FI CCDs and the backside-illuminated (BI) CCDs have evolved gradually with time. We demonstrate the efficacy of charge-transfer inefficiency (CTI) correction algorithms which recover some of the lost performance. The detection efficiency of the ACIS instrument has been declining throughout the mission, presumably due to a layer of contamination building up on the filter and/or CCDs. We present a characterization of the energy dependence of the excess absorption and demonstrate software which models the time dependence of the absorption from energies of 0.4 keV and up. The spectral redistribution function and the detection efficiency are well-characterized at energies from 1.5 to 8.0 keV. The calibration at energies below 1.5 keV is challenging because of the lack of strong lines in the calibration source and also because of the inherent non-linear dependence with energy of the CTI and the absorption by the contamination layer. We have been using data from celestial sources with relatively simple spectra to determine the quality of the calibration below 1.5 keV. The analysis of these observations demonstrate that the CTI correction recovers a significant fraction of the spectral resolution of the FI CCDs and the models of the time-dependent absorption result in consistent measurements of the flux at low energies for data from a BI (S3) CCD.

  20. Fourier-Based Spectral Analysis with Adaptive Resolution

    E-Print Network [OSTI]

    Andrey Khilko

    2008-06-04

    Despite being the most popular methods of data analysis, Fourier-based techniques suffer from the problem of static resolution that is currently believed to be a fundamental limitation of the Fourier Transform. Although alternative solutions overcome this limitation, none provide the simplicity, versatility, and convenience of the Fourier analysis. The lack of convenience often prevents these alternatives from replacing classical spectral methods - even in applications that suffer from the limitation of static resolution. This work demonstrates that, contrary to the generally accepted belief, the Fourier Transform can be generalized to the case of adaptive resolution. The generalized transform provides backward compatibility with classical spectral techniques and introduces minimal computational overhead.

  1. SPECTRAL AMPLITUDE AND PHASE EVOLUTION IN PETAWATT LASER PULSES

    SciTech Connect (OSTI)

    Filip, C V

    2010-11-22

    The influence of the active gain medium on the spectral amplitude and phase of amplified pulses in a CPA system is studied. Results from a 10-PW example based on Nd-doped mixed glasses are presented. In conclusion, this study shows that, by using spectral shaping and gain saturation in a mixed-glass amplifier, it is possible to produce 124 fs, 1.4 kJ laser pulses. One detrimental effect, the pulse distortion due to resonant amplification medium, has been investigated and its magnitude as well as its compensation calculated.

  2. High-gravity central stars

    E-Print Network [OSTI]

    Thomas Rauch

    2006-07-11

    NLTE spectral analyses of high-gravity central stars by means of state-of-the-art model atmosphere techniques provide information about the precursor AGB stars. The hydrogen-deficient post-AGB stars allow investigations on the intershell matter which is apparently exhibited at the stellar surface. We summarize recent results from imaging, spectroscopy, and spectropolarimetry.

  3. Tellus 000, 000000 (0000) Printed 14 March 2009 (Tellus LATEX style file v2.2) Modeling the Atmospheric Airborne Fraction in a Simple Carbon

    E-Print Network [OSTI]

    Khatiwala, Samar

    of anthropogenic CO2 emissions remaining in the atmosphere, known as the air- borne fraction (AF), has remained as the "airborne fraction", AF, defined as the ratio of the annual increase of atmospheric CO2 to total emissions atmospheric CO2 levels and hence climate are often justified on this basis. On the other hand, recent

  4. The probability of laser caused ocular injury to the aircrew of undetected aircraft violating the exclusion zone about the airborne aura LIDAR.

    SciTech Connect (OSTI)

    Augustoni, Arnold L.

    2006-12-01

    The probability of a laser caused ocular injury, to the aircrew of an undetected aircraft entering the exclusion zone about the AURA LIDAR airborne platform with the possible violation of the Laser Hazard Zone boundary, was investigated and quantified for risk analysis and management.

  5. Spectral and morphological analysis of the remnant of supernova 1987A with ALMA and ATCA

    SciTech Connect (OSTI)

    Zanardo, Giovanna; Staveley-Smith, Lister [International Centre for Radio Astronomy Research (ICRAR), M468, University of Western Australia, Crawley, WA 6009 (Australia); Indebetouw, Remy; Chevalier, Roger A. [Department of Astronomy, University of Virginia, P.O. Box 400325, Charlottesville, VA 22904 (United States); Matsuura, Mikako; Barlow, Michael J. [Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom); Gaensler, Bryan M. [Australian Research Council, Centre of Excellence for All-sky Astrophysics (CAASTRO) (Australia); Fransson, Claes; Lundqvist, Peter [Department of Astronomy, Oskar Klein Center, Stockholm University, AlbaNova, SE-106 91 Stockholm (Sweden); Manchester, Richard N. [CSIRO Astronomy and Space Science, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710 (Australia); Baes, Maarten [Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281 S9, B-9000 Gent (Belgium); Kamenetzky, Julia R. [Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721-0065 (United States); Laki?evi?, Maša [Institute for the Environment, Physical Sciences and Applied Mathematics, Lennard-Jones Laboratories, Keele University, Staffordshire ST5 5BG (United Kingdom); Marcaide, Jon M. [Departamento de Astronomía, Universidad de Valencia, C/Dr. Moliner 50, E-46100 Burjassot (Spain); Martí-Vidal, Ivan [Department of Earth and Space Sciences, Chalmers University of Technology, Onsala Space Observatory, SE-439 92 Onsala (Sweden); Meixner, Margaret [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Ng, C.-Y. [Department of Physics, University of Hong Kong, Pokfulam Road, Hong Kong (China); Park, Sangwook, E-mail: giovanna.zanardo@gmail.com [Department of Physics, University of Texas at Arlington, 108 Science Hall, Box 19059, Arlington, TX 76019 (United States); and others

    2014-12-01

    We present a comprehensive spectral and morphological analysis of the remnant of supernova (SN) 1987A with the Australia Telescope Compact Array (ATCA) and the Atacama Large Millimeter/submillimeter Array (ALMA). The non-thermal and thermal components of the radio emission are investigated in images from 94 to 672 GHz (? 3.2 mm to 450 ?m), with the assistance of a high-resolution 44 GHz synchrotron template from the ATCA, and a dust template from ALMA observations at 672 GHz. An analysis of the emission distribution over the equatorial ring in images from 44 to 345 GHz highlights a gradual decrease of the east-to-west asymmetry ratio with frequency. We attribute this to the shorter synchrotron lifetime at high frequencies. Across the transition from radio to far infrared, both the synchrotron/dust-subtracted images and the spectral energy distribution (SED) suggest additional emission beside the main synchrotron component (S {sub ?}??{sup –0.73}) and the thermal component originating from dust grains at T ? 22 K. This excess could be due to free-free flux or emission from grains of colder dust. However, a second flat-spectrum synchrotron component appears to better fit the SED, implying that the emission could be attributed to a pulsar wind nebula (PWN). The residual emission is mainly localized west of the SN site, as the spectral analysis yields –0.4 ? ? ? –0.1 across the western regions, with ? ? 0 around the central region. If there is a PWN in the remnant interior, these data suggest that the pulsar may be offset westward from the SN position.

  6. ENERGY-DEPENDENT POWER SPECTRAL STATES AND ORIGIN OF APERIODIC VARIABILITY IN BLACK HOLE BINARIES

    SciTech Connect (OSTI)

    Yu Wenfei; Zhang Wenda, E-mail: wenfei@shao.ac.cn [Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan Road, Shanghai 200030 (China)

    2013-06-20

    We found that the black hole candidate MAXI J1659-152 showed distinct power spectra, i.e., power-law noise (PLN) versus band-limited noise (BLN) plus quasi-periodic oscillations (QPOs) below and above about 2 keV, respectively, in observations with Swift and the Rossi X-ray Timing Explorer during the 2010 outburst, indicating a high energy cutoff of the PLN and a low energy cutoff of the BLN and QPOs around 2 keV. The emergence of the PLN and the fading of the BLN and QPOs initially took place below 2 keV when the source entered the hard intermediate state and settled in the soft state three weeks later. The evolution was accompanied by the emergence of the disk spectral component and decreases in the amplitudes of variability in the soft and hard X-ray bands. Our results indicate that the PLN is associated with an optically thick disk in both hard and intermediate states, and the power spectral state is independent of the X-ray energy spectral state in a broadband view. We suggest that in the hard or intermediate state, the BLN and QPOs emerge from the innermost hot flow subjected to Comptonization, while the PLN originates from the optically thick disk farther out. The energy cutoffs of the PLN and the BLN or QPOs then follow the temperature of the seed photons from the inner edge of the optically thick disk, while the high frequency cutoff of the PLN follows the orbital frequency of the inner edge of the optically thick disk as well.

  7. A Digital Low Dispersion Spectral Library Covering the 3500-7500AA Region Using the SAAO Radcliffe 1.9m Telescope's Cassegrain Spectrograph

    E-Print Network [OSTI]

    James, David

    2013-01-01

    We have created a digital spectral library, using low resolution optical spectra, of photometric and spectral standard stars. The data were acquired using the Cassegrain Spectrograph installed on the 1.9m Radcliffe telescope at the South African Astronomical Observatory. The library consists of optical wavelength (~ 3500-7500AA) spectra for main sequence and giant stars encompassing those most commonly observed in the Galaxy, namely the late-B, A-, F-, G-, K-, and early- to mid-M stars. We intend that our standard star spectra will be especially useful for spectral classification of stars in the field and Galactic clusters alike, and will have high pedagogic value when included into representative Introductory Astronomy or Stellar Astronomy curricula for undergraduate astronomy major and minor programs. We exploit the spectral library in order to derive spectral types for seventy-six optically and X-ray selected members of the young open cluster NGC 6475. Comparison of spectral-type, optical and infrared phot...

  8. PIXE-quantified AXSIA : elemental mapping by multivariate spectral analysis.

    SciTech Connect (OSTI)

    Doyle, Barney Lee; Antolak, Arlyn J. (Sandia National Labs, Livermore, CA); Campbell, J. L. (University of Guelph, Guelph, ON, Canada); Ryan, C. G. (CSIRO Exploration and Mining Bayview Road, Clayton VIC, Australia); Provencio, Paula Polyak; Barrett, Keith E. (Primecore Systems, Albuquerque, NM,); Kotula, Paul Gabriel

    2005-07-01

    Automated, nonbiased, multivariate statistical analysis techniques are useful for converting very large amounts of data into a smaller, more manageable number of chemical components (spectra and images) that are needed to describe the measurement. We report the first use of the multivariate spectral analysis program AXSIA (Automated eXpert Spectral Image Analysis) developed at Sandia National Laboratories to quantitatively analyze micro-PIXE data maps. AXSIA implements a multivariate curve resolution technique that reduces the spectral image data sets into a limited number of physically realizable and easily interpretable components (including both spectra and images). We show that the principal component spectra can be further analyzed using conventional PIXE programs to convert the weighting images into quantitative concentration maps. A common elemental data set has been analyzed using three different PIXE analysis codes and the results compared to the cases when each of these codes is used to separately analyze the associated AXSIA principal component spectral data. We find that these comparisons are in good quantitative agreement with each other.

  9. Noise Suppression and Spectral Decomposition for State-Dependent Noise

    E-Print Network [OSTI]

    Arnold, Elizabeth A.

    Noise Suppression and Spectral Decomposition for State-Dependent Noise in the Presence been shown that the observed noise amplitude of an intrinsically noisy system may be reduced by causing noise reduction in terms of the low-frequency end of the spectrum as well as the integrated spectrum

  10. Spectral Analysis and Connectivity of Porous Microstructures in Bone

    E-Print Network [OSTI]

    Golden, Kenneth M.

    that quantifies brine connectivity and its thermal evolution can also help assess the impact of osteoporosis on trabecular structure. Central to our approach is the spectral measure of a composite material, which contains, in dense cortical bone the pores can be sparse and disconnected, yet exhibit increasing volume fraction

  11. Spectral estimation on a sphere in geophysics and cosmology

    E-Print Network [OSTI]

    F. A. Dahlen; Frederik J Simons

    2007-05-22

    We address the problem of estimating the spherical-harmonic power spectrum of a statistically isotropic scalar signal from noise-contaminated data on a region of the unit sphere. Three different methods of spectral estimation are considered: (i) the spherical analogue of the one-dimensional (1-D) periodogram, (ii) the maximum likelihood method, and (iii) a spherical analogue of the 1-D multitaper method. The periodogram exhibits strong spectral leakage, especially for small regions of area $A\\ll 4\\pi$, and is generally unsuitable for spherical spectral analysis applications, just as it is in 1-D. The maximum likelihood method is particularly useful in the case of nearly-whole-sphere coverage, $A\\approx 4\\pi$, and has been widely used in cosmology to estimate the spectrum of the cosmic microwave background radiation from spacecraft observations. The spherical multitaper method affords easy control over the fundamental trade-off between spectral resolution and variance, and is easily implemented regardless of the region size, requiring neither non-linear iteration nor large-scale matrix inversion. As a result, the method is ideally suited for most applications in geophysics, geodesy or planetary science, where the objective is to obtain a spatially localized estimate of the spectrum of a signal from noisy data within a pre-selected and typically small region.

  12. VALIDATION OF SPECTRAL UNMIXING METHODS USING PHOTOMETRY AND TOPOGRAPHY INFORMATION

    E-Print Network [OSTI]

    Plaza, Antonio J.

    VALIDATION OF SPECTRAL UNMIXING METHODS USING PHOTOMETRY AND TOPOGRAPHY INFORMATION Rubén Marrero1 topography and photometry of the scene. The validation of the different methods and deconvolution processes topography and most importantly photometry are precisely known. On the other hand better distribution maps

  13. A spectral graph based approach to analyze hyperspectral data

    E-Print Network [OSTI]

    Bertozzi, Andrea L.

    A spectral graph based approach to analyze hyperspectral data Blake Hunter Department of Mathematics, UCLA 520 Portola Plaza Los Angeles, CA 90095 Email: blakehunter@math.ucla.edu Yifei Lou Department of Mathematics, UCLA 520 Portola Plaza Los Angeles, CA 90095 Email: bertozzi

  14. GIS and Spectral Soil Laboratory Key faculty member: Sabine Grunwald

    E-Print Network [OSTI]

    Ma, Lena

    GIS and Spectral Soil Laboratory Key faculty member: Sabine Grunwald Contact: Soil and Water information systems (GIS), geostatistical and statistical methods, space-time landscape modeling, remote laboratory. Available software include: MS Office Suite; MS SQL database; ArcGIS Suite (ESRI) including

  15. Vector spectral functions and transport properties in quenched QCD

    E-Print Network [OSTI]

    Heng-Tong Ding; Olaf Kaczmarek; Florian Meyer

    2014-12-18

    We present new results on the reconstruction of mesonic spectral functions for three temperatures $1.1T_c$, $1.2T_c$ and $1.4T_c$ in quenched QCD. Making use of non-perturbatively improved clover Wilson valence quarks allows for a clean extrapolation of correlator data to the continuum limit. For the case of vanishing momentum the spectral function is obtained by fitting the data to a well motivated ansatz, using the full covariance matrix of the continuum extrapolated data in the fit. We found that vector correlation function is almost temperature independent in the current temperature window. The electrical conductivity of the hot medium, related to the origin of the vector spectral function at zero momentum, is computed from the resulting parameters at all three temperatures, leading to an estimate of $0.2C_{em}\\lesssim \\sigma/T\\lesssim0.4C_{em}$. The dilepton rates resulting from the obtained spectral functions show no significant temperature dependence.

  16. Spectral Discrimination between Quarry Blasts and Earthquakes in Southern California

    E-Print Network [OSTI]

    Shearer, Peter

    Short Note Spectral Discrimination between Quarry Blasts and Earthquakes in Southern California, with the goal of developing methods to discriminate between these events. We process the spectra using reliable explosion discriminant than the S-to-P am- plitude ratio and works for about 90% of the events

  17. Typesetting spectral sequences in LATEX with Tilman Bauer

    E-Print Network [OSTI]

    Bauer, Tilman

    The present package, sseq, facilitates the typesetting of mathematical objects called spectral sequence charts circles or boxes, digits etc.), possibly decorated with labels, and between any two such symbols may or may not be a connection--e. g., a line, an arrow, or some curved line. The sseq package is built

  18. Surface temperature and spectral measurements at Santiaguito lava dome, Guatemala

    E-Print Network [OSTI]

    Rose, William I.

    Surface temperature and spectral measurements at Santiaguito lava dome, Guatemala Steve T. M, Michigan Technological University, Houghton, Michigan, USA Otoniel Matias INSIVUMEH, Guatemala City, Guatemala Received 4 June 2004; revised 23 July 2004; accepted 20 September 2004; published 13 October 2004

  19. SPECTRAL SOLAR IRRADIANCE AND ITS ENTROPIC EFFECT ON EARTH'S CLIMATE

    E-Print Network [OSTI]

    comparison with a conventional approach by using a blackbody Sun's brightness temperature exhibits Experiment (SORCE) satellite are used to examine the magnitude and spectral distribution of the Earth radiation received at the top of the atmosphere (TOA) is the same as that radiated at the Sun's surface

  20. THE INFRARED TELESCOPE FACILITY (IRTF) SPECTRAL LIBRARY: COOL STARS

    SciTech Connect (OSTI)

    Rayner, John T.; Cushing, Michael C.; Vacca, William D. E-mail: michael.cushing@gmail.com

    2009-12-01

    We present a 0.8-5 {mu}m spectral library of 210 cool stars observed at a resolving power of R {identical_to} {lambda}/{delta}{lambda} {approx} 2000 with the medium-resolution infrared spectrograph, SpeX, at the 3.0 m NASA Infrared Telescope Facility (IRTF) on Mauna Kea, Hawaii. The stars have well-established MK spectral classifications and are mostly restricted to near-solar metallicities. The sample not only contains the F, G, K, and M spectral types with luminosity classes between I and V, but also includes some AGB, carbon, and S stars. In contrast to some other spectral libraries, the continuum shape of the spectra is measured and preserved in the data reduction process. The spectra are absolutely flux calibrated using the Two Micron All Sky Survey photometry. Potential uses of the library include studying the physics of cool stars, classifying and studying embedded young clusters and optically obscured regions of the Galaxy, evolutionary population synthesis to study unresolved stellar populations in optically obscured regions of galaxies and synthetic photometry. The library is available in digital form from the IRTF Web site.

  1. SPECTRAL PROBLEMS FOR OPERATORS WITH CROSSED MAGNETIC AND ELECTRIC FIELDS

    E-Print Network [OSTI]

    Petkov, Vesselin

    SPECTRAL PROBLEMS FOR OPERATORS WITH CROSSED MAGNETIC AND ELECTRIC FIELDS MOUEZ DIMASSI Consider the two-dimensional Schr¨odinger operator with homogeneous magnetic and electric fields H = H and > 0 are proportional to the strength of the homogeneous magnetic and electric fields and V (x, y

  2. A spectral comparison of (379) Huenna and its satellite

    E-Print Network [OSTI]

    DeMeo, Francesca E.

    We present near-infrared spectral measurements of Themis family Asteroid (379) Huenna (D ? 98 km) and its 6 km satellite using SpeX on the NASA IRTF. The companion was farther than 1.5? from the primary at the time of ...

  3. Measuring absolute infrared spectral radiance with correlated photons: new arrangements

    E-Print Network [OSTI]

    Migdall, Alan

    metrologia Measuring absolute infrared spectral radiance with correlated photons: new arrangements radiance using correlated photons are presented. The method has the remarkable feature that it allows be measured using correlated photons [1-4]. That work outlined some of the useful features of the method. One

  4. University of Alberta A MULTI-SPECTRAL DECIMATION SCHEME FOR

    E-Print Network [OSTI]

    Roberts, Malcolm

    University of Alberta A MULTI-SPECTRAL DECIMATION SCHEME FOR TURBULENCE SIMULATIONS by Malcolm Ian and Statistical Sciences c Malcolm Ian William Roberts Fall, 2006 Edmonton, Alberta Permission is hereby granted to the University of Alberta Libraries to reproduce single #12;copies of this thesis and to lend or sell such copies

  5. Kernel spectral clustering for predicting maintenance of industrial machines

    E-Print Network [OSTI]

    status, but the operations are labor inten- sive and prone to human errors. Condition-based maintenance monitoring of machine parts leads to reliable and accurate lifetime predictions, and maintenance operationsKernel spectral clustering for predicting maintenance of industrial machines Rocco Langone1, Carlos

  6. Spectral characteristics of single and coupled microresonator lasers comprising a

    E-Print Network [OSTI]

    Cunningham, Brian

    Spectral characteristics of single and coupled microresonator lasers comprising a replica-molded introduced defect (2 section removed) have been examined with respect to the output spectrum, pump energy of intentionally introduced defects or coupled arrays of resonators to control the characteristics of microla- sers

  7. Buccal Spectral Markers for Lung Cancer Risk Stratification

    E-Print Network [OSTI]

    Hartline, Jason D.

    Buccal Spectral Markers for Lung Cancer Risk Stratification Andrew J. Radosevich1 *, Nikhil N, United States of America Abstract Lung cancer remains the leading cause of cancer deaths in the US with .150,000 deaths per year. In order to more effectively reduce lung cancer mortality, more sophisticated

  8. Wavelet Approach for Operational Gamma Spectral Peak Detection - Preliminary Assessment

    SciTech Connect (OSTI)

    ,

    2012-02-01

    Gamma spectroscopy for radionuclide identifications typically involves locating spectral peaks and matching the spectral peaks with known nuclides in the knowledge base or database. Wavelet analysis, due to its ability for fitting localized features, offers the potential for automatic detection of spectral peaks. Past studies of wavelet technologies for gamma spectra analysis essentially focused on direct fitting of raw gamma spectra. Although most of those studies demonstrated the potentials of peak detection using wavelets, they often failed to produce new benefits to operational adaptations for radiological surveys. This work presents a different approach with the operational objective being to detect only the nuclides that do not exist in the environment (anomalous nuclides). With this operational objective, the raw-count spectrum collected by a detector is first converted to a count-rate spectrum and is then followed by background subtraction prior to wavelet analysis. The experimental results suggest that this preprocess is independent of detector type and background radiation, and is capable of improving the peak detection rates using wavelets. This process broadens the doors for a practical adaptation of wavelet technologies for gamma spectral surveying devices.

  9. Running of scalar spectral index in multi-field inflation

    E-Print Network [OSTI]

    Jinn-Ouk Gong

    2015-05-20

    We compute the running of the scalar spectral index in general multi-field slow-roll inflation. By incorporating explicit momentum dependence at the moment of horizon crossing, we can find the running straightforwardly. At the same time, we can distinguish the contributions from the quasi de Sitter background and the super-horizon evolution of the field fluctuations.

  10. Arrival time and magnitude of airborne fission products from the Fukushima, Japan, reactor incident as measured in Seattle, WA, USA

    E-Print Network [OSTI]

    J. Diaz Leon; D. A. Jaffe; J. Kaspar; A. Knecht; M. L. Miller; R. G. H. Robertson; A. G. Schubert

    2011-08-23

    We report results of air monitoring started due to the recent natural catastrophe on 11 March 2011 in Japan and the severe ensuing damage to the Fukushima Dai-ichi nuclear reactor complex. On 17-18 March 2011, we registered the first arrival of the airborne fission products 131-I, 132-I, 132-Te, 134-Cs, and 137-Cs in Seattle, WA, USA, by identifying their characteristic gamma rays using a germanium detector. We measured the evolution of the activities over a period of 23 days at the end of which the activities had mostly fallen below our detection limit. The highest detected activity amounted to 4.4 +/- 1.3 mBq/m^3 of 131-I on 19-20 March.

  11. A Constant Spectral Index for Sagittarius A* During Infrared/X-ray Intensity Variations

    E-Print Network [OSTI]

    S. D. Hornstein; K. Matthews; A. M. Ghez; J. R. Lu; M. Morris; E. E. Becklin; M. Rafelski; F. K. Baganoff

    2007-06-12

    We report the first time-series of broadband infrared (IR) color measurements of Sgr A*, the variable emission source associated with the supermassive black hole at the Galactic Center. Using the laser and natural guide star AO systems on the Keck II telescope, we imaged Sgr A* in multiple near-infrared broadband filters with a typical cycle time of ~3 min during 4 observing runs (2005-2006), two of which were simultaneous with Chandra X-ray measurements. In spite of the large range of dereddened flux densities for Sgr A* (2-30 mJy), all of our near-IR measurements are consistent with a constant spectral index of alpha = -0.6+-0.2. Furthermore, this value is consistent with the spectral indices observed at X-ray wavelengths during nearly all outbursts; which is consistent with the synchrotron self-Compton model for the production of the X-ray emission. During the coordinated observations, one IR outburst occurs 1 GeV is generated, and it is this high-energy tail that gives rise to the X-ray outbursts. One possible explanation for this type of variation is from the turbulence induced by a magnetorotational instability, in which the outer scale length of the turbulence varies and changes the high-energy cutoff.

  12. Spectrally resolved detection of sodium in the atmosphere of HD189733b with the HARPS spectrograph

    E-Print Network [OSTI]

    Wyttenbach, A; Lovis, C; Udry, S; Pepe, F

    2015-01-01

    Atmospheric properties of exoplanets can be constrained with transit spectroscopy. The signature of atomic sodium NaI, known to be present above the clouds, is a powerful probe of the upper atmosphere, where it can be best detected and characterized at high spectral resolution. Our goal is to obtain a high-resolution transit spectrum of HD189733b in the region around the resonance doublet of NaI at 589 nm, to characterize the absorption signature previously detected from space at low resolution. We analyze archival transit data of HD189733b obtained with the HARPS spectrograph. We retrieve the transit spectrum and light curve of the planet, implementing corrections for telluric contamination and planetary orbital motion. We spectrally resolve the NaI D doublet and measure line contrasts of $0.64\\pm0.07\\%$ (D2) and $0.40\\pm0.07\\%$ (D1) and FWHMs of $0.52\\pm0.08~\\AA$. This corresponds to a detection at the 10-$\\sigma$ level of excess of absorption of $0.32\\pm0.03\\%$ in a passband of $2\\times0.75\\ \\AA$ centered ...

  13. A STATISTICAL STUDY OF SPECTRAL HARDENING IN SOLAR FLARES AND RELATED SOLAR ENERGETIC PARTICLE EVENTS

    SciTech Connect (OSTI)

    Grayson, James A.; Krucker, Saem [Space Sciences Laboratory, University of California, Berkeley, CA 94720-7450 (United States); Lin, R. P., E-mail: jgrayson@berkeley.ed, E-mail: krucker@ssl.berkeley.ed, E-mail: rlin@ssl.berkeley.ed [Also at Department of Physics, University of California, Berkeley, CA 94720-7300 (United States)

    2009-12-20

    Using hard X-ray observations from the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI), we investigate the reliability of spectral hardening during solar flares as an indicator of related solar energetic particle (SEP) events at Earth. All RHESSI data are analyzed, from 2002 February through the end of Solar Cycle 23, thereby expanding upon recent work on a smaller sample of flares. Previous investigations have found very high success when associating soft-hard-harder (SHH) spectral behavior with energetic proton events, and confirmation of this link would suggest a correlation between electron acceleration in solar flares and SEPs seen in interplanetary space. In agreement with these past findings, we find that of 37 magnetically well-connected flares (W30-W90), 12 of 18 flares with SHH behavior produced SEP events and none of 19 flares without SHH behavior produced SEPs. This demonstrates a statistically significant dependence of SHH and SEP observations, a link that is unexplained in the standard scenario of SEP acceleration at the shock front of coronal mass ejections and encourages further investigation of the mechanisms which could be responsible.

  14. Unmanned airborne vehicle (UAV): Flight testing and evaluation of two-channel E-field very low frequency (VLF) instrument

    SciTech Connect (OSTI)

    1998-12-01

    Using VLF frequencies, transmitted by the Navy`s network, for airborne remote sensing of the earth`s electrical, magnetic characteristics was first considered by the United States Geological Survey (USGS) around the mid 1970s. The first VLF system was designed and developed by the USGS for installation and operation on a single engine, fixed wing aircraft used by the Branch of Geophysics for geophysical surveying. The system consisted of five channels. Two E-field channels with sensors consisting of a fixed vertical loaded dipole antenna with pre-amp mounted on top of the fuselage and a gyro stabilized horizontal loaded dipole antenna with pre-amp mounted on a tail boom. The three channel magnetic sensor consisted of three orthogonal coils mounted on the same gyro stabilized platform as the horizontal E-field antenna. The main features of the VLF receiver were: narrow band-width frequency selection using crystal filters, phase shifters for zeroing out system phase variances, phase-lock loops for generating real and quadrature gates, and synchronous detectors for generating real and quadrature outputs. In the mid 1990s the Branch of Geophysics designed and developed a two-channel E-field ground portable VLF system. The system was built using state-of-the-art circuit components and new concepts in circuit architecture. Small size, light weight, low power, durability, and reliability were key considerations in the design of the instrument. The primary purpose of the instrument was for collecting VLF data during ground surveys over small grid areas. Later the system was modified for installation on a Unmanned Airborne Vehicle (UAV). A series of three field trips were made to Easton, Maryland for testing and evaluating the system performance.

  15. Analyzing source apportioned methane in northern California during Discover-AQ-CA using airborne measurements and model simulations

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Johnson, Matthew S.; Yates, Emma L.; Iraci, Laura T.; Loewenstein, Max; Tadi?, Jovan M.; Wecht, Kevin J.; Jeong, Seongeun; Fischer, Marc L.

    2014-12-01

    This study analyzes source apportioned methane (CH4) emissions and atmospheric mixing ratios in northern California during the Discover-AQ-CA field campaign using airborne measurement data and model simulations. Source apportioned CH4 emissions from the Emissions Database for Global Atmospheric Research (EDGAR) version 4.2 were applied in the 3-D chemical transport model GEOS-Chem and analyzed using airborne measurements taken as part of the Alpha Jet Atmospheric eXperiment over the San Francisco Bay Area (SFBA) and northern San Joaquin Valley (SJV). During the time period of the Discover-AQ-CA field campaign EDGAR inventory CH4 emissions were ~5.30 Gg day –1 (Gg = 1.0 ×more »109 g) (equating to ~1.90 × 103 Gg yr–1) for all of California. According to EDGAR, the SFBA and northern SJV region contributes ~30% of total CH4 emissions from California. Source apportionment analysis during this study shows that CH4 mixing ratios over this area of northern California are largely influenced by global emissions from wetlands and local/global emissions from gas and oil production and distribution, waste treatment processes, and livestock management. Model simulations, using EDGAR emissions, suggest that the model under-estimates CH4 mixing ratios in northern California (average normalized mean bias (NMB) = –5.2% and linear regression slope = 0.20). The largest negative biases in the model were calculated on days when large amounts of CH4 were measured over local emission sources and atmospheric CH4 mixing ratios reached values >2.5 parts per million. Sensitivity emission studies conducted during this research suggest that local emissions of CH4 from livestock management processes are likely the primary source of the negative model bias. These results indicate that a variety, and larger quantity, of measurement data needs to be obtained and additional research is necessary to better quantify source apportioned CH4 emissions in California.« less

  16. A Framework for HI Spectral Source Finding Using Distributed-Memory Supercomputing

    E-Print Network [OSTI]

    Westerlund, Stefan

    2014-01-01

    The latest generation of radio astronomy interferometers will conduct all sky surveys with data products consisting of petabytes of spectral line data. Traditional approaches to identifying and parameterising the astrophysical sources within this data will not scale to datasets of this magnitude, since the performance of workstations will not keep up with the real-time generation of data. For this reason, it is necessary to employ high performance computing systems consisting of a large number of processors connected by a high-bandwidth network. In order to make use of such supercomputers substantial modifications must be made to serial source finding code. To ease the transition, this work presents the Scalable Source Finder Framework, a framework providing storage access, networking communication and data composition functionality, which can support a wide range of source finding algorithms provided they can be applied to subsets of the entire image. Additionally, the Parallel Gaussian Source Finder was imp...

  17. Non-parametric Image Registration of Airborne LiDAR, Hyperspectral and Photographic Imagery of Wooded Landscapes

    E-Print Network [OSTI]

    Lee, Juheon; Cai, Xiaohao; Schönlieb, Carola-Bibiane; Coomes, David A.

    2015-06-02

    spectrometers measure solar energy reflected off the Earth’s surface within a swath of land. Hyper- spectral data were gathered using the AISA Eagle and AISA Hawk sensors (Specim Ltd., Finland), which are pushbroom sen- sors with 255 and 256 spectral bands... | obtained by using established methods NCC, MI, NGF, SURF, as well as our NGF-Curv method. The results of registration methods are denoted by TNCCreg , T MI reg , T NGF reg , T SURF reg , and TNGF-Curvreg , respectively, in these panels; yellow circle...

  18. Tonopah Test Range Air Monitoring: CY2013 Meteorological, Radiological, and Airborne Particulate Observations

    SciTech Connect (OSTI)

    Mizell, Steve A; Nikolich, George; Shadel, Craig; McCurdy, Greg; Etyemezian, Vicken; Miller, Julianne J

    2014-10-01

    In 1963, the U.S. Department of Energy (DOE) (formerly the Atomic Energy Commission [AEC]), implemented Operation Roller Coaster on the Tonopah Test Range (TTR) and an adjacent area of the Nevada Test and Training Range (NTTR) (formerly the Nellis Air Force Range). This test resulted in radionuclide-contaminated soils at Clean Slate I, II, and III. This report documents observations made during on-going monitoring of radiological, meteorological, and dust conditions at stations installed adjacent to Clean Slate I and Clean Slate III and at the TTR Range Operations Control center. The primary objective of the monitoring effort is to determine if winds blowing across the Clean Slate sites are transporting particles of radionuclide-contaminated soils beyond both the physical and administrative boundaries of the sites. Results for the calendar year (CY) 2013 monitoring include: (1) the gross alpha and gross beta values from the monitoring stations are approximately equivalent to the highest values observed during the CY2012 reporting at the surrounding Community Environmental Monitoring Program (CEMP) stations (this was the latest documented data available at the time of this writing); (2) only naturally occurring radionuclides were identified in the gamma spectral analyses; (3) the ambient gamma radiation measurements indicate that the average annual gamma exposure is similar at all three monitoring stations and periodic intervals of increased gamma values appear to be associated with storm fronts passing through the area; and (4) the concentrations of both resuspended dust and saltated sand particles generally increase with increasing wind speed. However, differences in the observed dust concentrations are likely due to differences in the soil characteristics immediately adjacent to the monitoring stations. Neither the resuspended particulate radiological analyses nor the ambient gamma radiation measurements suggest wind transport of radionuclide-contaminated soils.

  19. Collective coordinates for nuclear spectral densities in energy transfer and femtosecond spectroscopy of molecular aggregates

    E-Print Network [OSTI]

    Mukamel, Shaul

    Collective coordinates for nuclear spectral densities in energy transfer and femtosecond collective nuclear coordinates necessary to represent a given set of spectral densities is obtained coordinates phase space. The signatures of excitonic and nuclear motions in ultrafast fluorescence

  20. Hadronic Spectral Functions above the QCD Phase Transition

    E-Print Network [OSTI]

    M. Asakawa; T. Hatsuda; Y. Nakahara

    2002-08-27

    We extract the spectral functions in the scalar, pseudo-scalar, vector, and axial vector channels above the deconfinement phase transition temperature (Tc) using the maximum entropy method (MEM). We use anisotropic lattices, 32^3 * 32, 40, 54, 72, 80, and 96 (corresponding to T = 2.3 Tc --> 0.8 Tc), with the renormalized anisotropy xi = 4.0 to have enough temporal data points to carry out the MEM analysis. Our result suggests that the spectral functions continue to possess non-trivial structures even above Tc and in addition that there is a qualitative change in the state of the deconfined matter between 1.5 Tc and 2 Tc.

  1. Information-Efficient Spectral Imaging Sensor With Tdi

    DOE Patents [OSTI]

    Rienstra, Jeffrey L. (Albuquerque, NM); Gentry, Stephen M. (Albuquerque, NM); Sweatt, William C. (Albuquerque, NM)

    2004-01-13

    A programmable optical filter for use in multispectral and hyperspectral imaging employing variable gain time delay and integrate arrays. A telescope focuses an image of a scene onto at least one TDI array that is covered by a multispectral filter that passes separate bandwidths of light onto the rows in the TDI array. The variable gain feature of the TDI array allows individual rows of pixels to be attenuated individually. The attenuations are functions of the magnitudes of the positive and negative components of a spectral basis vector. The spectral basis vector is constructed so that its positive elements emphasize the presence of a target and its negative elements emphasize the presence of the constituents of the background of the imaged scene. This system provides for a very efficient determination of the presence of the target, as opposed to the very data intensive data manipulations that are required in conventional hyperspectral imaging systems.

  2. Soliton communication lines based on spectrally efficient modulation formats

    SciTech Connect (OSTI)

    Yushko, O V; Redyuk, A A

    2014-06-30

    We report the results of mathematical modelling of optical-signal propagation in soliton fibre-optic communication lines (FOCLs) based on spectrally efficient signal modulation formats. We have studied the influence of spontaneous emission noise, nonlinear distortions and FOCL length on the data transmission quality. We have compared the characteristics of a received optical signal for soliton and conventional dispersion compensating FOCLs. It is shown that in the presence of strong nonlinearity long-haul soliton FOCLs provide a higher data transmission performance, as well as allow higher order modulation formats to be used as compared to conventional communication lines. In the context of a coherent data transmission, soliton FOCLs allow the use of phase modulation with many levels, thereby increasing the spectral efficiency of the communication line. (optical communication lines)

  3. Synthesis of the Beryllium 3131A Spectral Region

    E-Print Network [OSTI]

    Johanna F. Ashwell; R. D. Jeffries; B. Smalley

    2005-09-19

    The Beryllium spectral region of the Sun, Procyon and 4 stars in the open cluster NGC6633 up to Teff = 7500K have been synthesised using ATLAS9 model atmospheres and the MOOG spectral synthesis program. The line list used for these syntheses has been modified from the ATLAS9 line list to improve the quality of the fits in light of the improved opacities in the new version of the MOOG code. Significant changes have been made to the Mn I line at ATLAS9 wavelength 3131.037A and an OH line has been added at 3131.358A. In addition there are a number of minor changes to gf-values throughout the synthesised region thus improving the fit for the spectra across the temperature range considerably.

  4. Spectral Type and Radial Velocity Variations in Three SRC Variables

    E-Print Network [OSTI]

    Moncrieff, Kathleen E; Short, C Ian; Bennett, Philip D; Balam, David D; Griffin, Roger F

    2011-01-01

    SRC variables are M supergiants, precursors to Type II supernovae, that vary in brightness with moderately regular periods of order 100-1000 days. Although identified as pulsating stars that obey their own period-luminosity relation, few have been examined in enough detail to follow the temperature and spectral changes that they undergo during their long cycles. The present study examines such changes for several SRC variables revealed by CCD spectra obtained at the Dominion Astrophysical Observatory (DAO) during 2005-2009, as well as by archival spectra from the DAO (and elsewhere) for some stars from the 1960s to 1980s, and Cambridge radial velocity spectrometer measures for Betelgeuse. Described here is our classification procedure and information on the spectral type and radial velocity changes in three of the stars. The results provide insights into the pulsation mechanism in M supergiants.

  5. Charmonium correlators and spectral functions at finite temperature

    SciTech Connect (OSTI)

    Ding,H.T.; Kaczmarek, O.; Karsch, F.; Satz, H.

    2008-09-01

    We present an operational approach to address the in-medium behavior of charmonium and analyze the reliability of maximum entropy method (MEM). We study the dependences of the ratio of correlators to the reconstructed one and the free one on the resonance's width and the continuum's threshold. Furthermore, we discuss the issue of the default model dependence of the spectral function obtained from MEM.

  6. BROADBAND SPECTRAL INVESTIGATIONS OF SGR J1550-5418 BURSTS

    SciTech Connect (OSTI)

    Lin Lin; Goegues, Ersin; Kaneko, Yuki [Faculty of Engineering and Natural Sciences, Sabanc Latin-Small-Letter-Dotless-I University, Orhanl Latin-Small-Letter-Dotless-I Tuzla, Istanbul 34956 (Turkey); Baring, Matthew G. [Department of Physics and Astronomy, Rice University, MS-108, P.O. Box 1892, Houston, TX 77251 (United States); Granot, Jonathan [Racah Institute of Physics, Hebrew University, Jerusalem 91904 (Israel); Kouveliotou, Chryssa [Space Science Office, VP62, NASA/Marshall Space Flight Center, Huntsville, AL 35812 (United States); Van der Horst, Alexander; Watts, Anna L. [Astronomical Institute 'Anton Pannekoek', University of Amsterdam, Postbus 94249, 1090 GE Amsterdam (Netherlands); Gruber, David; Von Kienlin, Andreas [Max-Planck-Institut fuer extraterrestrische Physik, Postfach 1312, D-85748 Garching bei Mnchen (Germany); Younes, George [USRA, National Space Science and Technology Center, 320 Sparkman Drive, Huntsville, AL 35805 (United States); Gehrels, Neil, E-mail: linlin@sabanciuniv.edu [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

    2012-09-01

    We present the results of our broadband spectral analysis of 42 SGR J1550-5418 bursts simultaneously detected with the Swift/X-ray Telescope (XRT) and the Fermi/Gamma-ray Burst Monitor (GBM), during the 2009 January active episode of the source. The unique spectral and temporal capabilities of the XRT windowed timing mode have allowed us to extend the GBM spectral coverage for these events down to the X-ray domain (0.5-10 keV). Our earlier analysis of the GBM data found that the SGR J1550-5418 burst spectra were described equally well with either a Comptonized model or with two blackbody functions; the two models were statistically indistinguishable. Our new broadband (0.5-200 keV) spectral fits show that, on average, the burst spectra are better described with two blackbody functions than with the Comptonized model. Thus, our joint XRT-GBM analysis clearly shows for the first time that the SGR J1550-5418 burst spectra might naturally be expected to exhibit a more truly thermalized character, such as a two-blackbody or even a multi-blackbody signal. Using the Swift and RXTE timing ephemeris for SGR J1550-5418 we construct the distribution of the XRT burst counts with spin phase and find that it is not correlated with the persistent X-ray emission pulse phase from SGR J1550-5418. These results indicate that the burst emitting sites on the neutron star need not to be co-located with hot spots emitting the bulk of the persistent X-ray emission. Finally, we show that there is a significant pulse phase dependence of the XRT burst counts, likely demonstrating that the surface magnetic field of SGR J1550-5418 is not uniform over the emission zones, since it is anticipated that regions with stronger surface magnetic field could trigger bursts more efficiently.

  7. Energy efficient residential new construction: market transformation. Spectral selective glass. Final project report

    SciTech Connect (OSTI)

    Hammon, Robert

    2000-12-18

    This final report describes the following tasks associated with this project: cost and availability of spectrally selective glass (SSG); window labeling problem and field verification of glass; availability of SSG replacement glass and tempered glass; HVAC load reduction due to spectrally selective glass; and comsumer appreciation of spectrally selective glass. Also included in the report are four attachments: builder and HVAC subcontractor presentation, sample advertisements, spectrally selective glass demonstration model, and invitation to SCE Glass mini trade-show.

  8. Cosmic variance of the spectral index from mode coupling

    SciTech Connect (OSTI)

    Bramante, Joseph; Kumar, Jason [Department of Physics and Astronomy, University of Hawaii, 2505 Correa Rd., Honolulu HI (United States); Nelson, Elliot; Shandera, Sarah, E-mail: bramante@hawaii.edu, E-mail: jkumar@hawaii.edu, E-mail: eln121@psu.edu, E-mail: shandera@gravity.psu.edu [Institute for Gravitation and the Cosmos, The Pennsylvania State University, University Park, PA 16802 (United States)

    2013-11-01

    We demonstrate that local, scale-dependent non-Gaussianity can generate cosmic variance uncertainty in the observed spectral index of primordial curvature perturbations. In a universe much larger than our current Hubble volume, locally unobservable long wavelength modes can induce a scale-dependence in the power spectrum of typical subvolumes, so that the observed spectral index varies at a cosmologically significant level (|?n{sub s}| ? O(0.04)). Similarly, we show that the observed bispectrum can have an induced scale dependence that varies about the global shape. If tensor modes are coupled to long wavelength modes of a second field, the locally observed tensor power and spectral index can also vary. All of these effects, which can be introduced in models where the observed non-Gaussianity is consistent with bounds from the Planck satellite, loosen the constraints that observations place on the parameters of theories of inflation with mode coupling. We suggest observational constraints that future measurements could aim for to close this window of cosmic variance uncertainty.

  9. Innovative static spectropolarimeter concept for wide spectral ranges: tolerancing study

    E-Print Network [OSTI]

    Pertenais, Martin; Parès, Laurent; Petit, Pascal

    2015-01-01

    Developing an efficient and robust polarimeter for wide spectral ranges and space applications is a main issue in many projects. As part of the UVMag consortium created to develop UV facilities in space (e.g. the Arago mission proposed to ESA), we are studying an innovative concept of polarimeter that is robust, simple, and efficient on a wide spectral range. The idea, based on the article by Sparks et al. (2012), is to use polarization scramblers to create a spatial modulation of the polarization. Along the height of the wedges of the scramblers, the thickness of the birefringent material crossed by the light, and thus the retardance, vary continuously. This variation creates an intensity modulation of the light related to the entrance polarization state. Analyzing this modulation with a linear polarizer, and dispersing the light spectrally in the orthogonal spatial direction, enables the measurement of the full Stokes vector over the entire spectrum. This determination is performed with a single-shot measur...

  10. Vector Meson Spectral Functions in a Coarse-Graining Approach

    E-Print Network [OSTI]

    Stephan Endres; Hendrik van Hees; Janus Weil; Marcus Bleicher

    2015-03-26

    Dilepton production in heavy-ion collisions at top SPS energy is investigated within a coarse-graining approach that combines an underlying microscopic evolution of the nuclear reaction with the application of medium-modified spectral functions. Extracting local energy and baryon density for a grid of small space-time cells and going to each cell's rest frame enables to determine local temperature and chemical potential by application of an equation of state. This allows for the calculation of thermal dilepton emission. We apply and compare two different spectral functions for the $\\rho$: A hadronic many-body calculation and an approach that uses empirical scattering amplitudes. Quantitatively good agreement of the model calculations with the data from the NA60 collaboration is achieved for both spectral functions, but in detail the hadronic many-body approach leads to a better description, especially of the broadening around the pole mass of the $\\rho$ and for the low-mass excess. We further show that the presence of a pion chemical potential significantly influences the dilepton yield.

  11. On the detection of spectral ripples from the Recombination Epoch

    E-Print Network [OSTI]

    Rao, Mayuri Sathyanarayana; Shankar, N Udaya; Chluba, Jens

    2015-01-01

    Photons emitted during the epochs of Hydrogen ($500 \\lesssim z \\lesssim 1600$) and Helium recombination ($1600 \\lesssim z \\lesssim 3500$ for HeII $\\rightarrow$ HeI, $5000 \\lesssim z \\lesssim 8000$ for HeIII $\\rightarrow$ HeII) are predicted to appear as broad, weak spectral distortions of the Cosmic Microwave Background. We present a feasibility study for a ground-based experimental detection of these recombination lines, which would provide an observational constraint on the thermal ionization history of the Universe, uniquely probing astrophysical cosmology beyond the last scattering surface. We find that an octave band in the 2--6 GHz window is optimal for such an experiment, both maximizing signal-to-noise ratio and including sufficient line spectral structure. At these frequencies the predicted signal appears as an additive quasi-sinusoidal component with amplitude about $8$ nK that is embedded in a sky spectrum some nine orders of magnitude brighter. We discuss an algorithm to detect these tiny spectral...

  12. Scalar spectral measures associated with an operator-fractal

    SciTech Connect (OSTI)

    Jorgensen, Palle E. T., E-mail: jorgen@math.uiowa.edu [Department of Mathematics, The University of Iowa, Iowa City, Iowa 52242-1419 (United States)] [Department of Mathematics, The University of Iowa, Iowa City, Iowa 52242-1419 (United States); Kornelson, Keri A., E-mail: kkornelson@ou.edu [Department of Mathematics, The University of Oklahoma, Norman, Oklahoma 73019-0315 (United States); Shuman, Karen L. [Department of Mathematics and Statistics, Grinnell College, Grinnell, Iowa 50112-1690 (United States)] [Department of Mathematics and Statistics, Grinnell College, Grinnell, Iowa 50112-1690 (United States)

    2014-02-15

    We study a spectral-theoretic model on a Hilbert space L{sup 2}(?) where ? is a fixed Cantor measure. In addition to ?, we also consider an independent scaling operator U acting in L{sup 2}(?). To make our model concrete, we focus on explicit formulas: We take ? to be the Bernoulli infinite-convolution measure corresponding to scale number 1/4 . We then define the unitary operator U in L{sup 2}(?) from a scale-by-5 operation. The spectral-theoretic and geometric properties we have previously established for U are as follows: (i) U acts as an ergodic operator; (ii) the action of U is not spatial; and finally, (iii) U is fractal in the sense that it is unitarily equivalent to a countable infinite direct sum of (twisted) copies of itself. In this paper, we prove new results about the projection-valued measures and scalar spectral measures associated to U and its constituent parts. Our techniques make use of the representations of the Cuntz algebra O{sub 2} on L{sup 2}(?)

  13. Spectral solar irradiance before and during a Harmattan dust spell

    SciTech Connect (OSTI)

    Adeyefa, Z.D. [Federal Univ. of Technology, Akure (Nigeria)] [Federal Univ. of Technology, Akure (Nigeria); Holmgren, B. [Uppsala Univ. (Sweden)] [Uppsala Univ. (Sweden)

    1996-09-01

    Measurements of the ground-level spectral distributions of the direct, diffuse and global solar irradiance between 300 and 1100 nm were made at Akure (7.15{degree}N, 5.5{degree}E), Nigeria, in December 1991 before and during a Harmattan dust spell employing a spectroradiometer (LICOR LI-1800) with 6 nm resolution. The direct spectral solar irradiance which was initially reduced before the dust storm was further attenuated by about 50% after the spell. Estimated values of the Angstrom turbidity coefficient {beta} indicated an increase of about 146% of this parameter while the Angstrom wavelength-exponent {alpha} decreased by about 65% within the 2-day study period. The spectral diffuse-to-direct and diffuse-to-global ratios suggest that the main cause of the significant reduction in solar irradiance at the surface was the scattering by the aerosol which led to an increase in the diffuse component. The global irradiance though reduced, was less sensitive to changing Harmattan conditions. It is recommended that solar energy devices that use radiation from Sun and sky be used under fluctuating Harmattan conditions. There are some deviations from the Angstrom formula under very turbid Harmattan conditions which could be explained by the relative increase of the particle sizes. 31 refs., 12 figs., 3 tabs.

  14. Electron Acceleration in Solar Flares: Theory of Spectral Evolution

    E-Print Network [OSTI]

    Paolo C. Grigis; Arnold O. Benz

    2006-08-14

    Context: Stochastic acceleration is thought to be a key mechanism in the energization of solar flare electrons. Aims: We study whether stochastic acceleration can reproduce the observed soft-hard-soft evolution of the spectral features of the hard X-ray emitted by suprathermal electron. We pay special attention to the effects of particle trapping and escape. Methods: The Fokker-Planck equation for the electron distribution is integrated numerically using the coefficients derived by Miller et al. for transit-time damping acceleration. The electron spectra are then converted to photon spectra for comparison with RHESSI observation of looptop sources. Results: The presence of particle escape softens the model spectra computed in the stochastic acceleration framework. The ratio between the efficiency of trapping and acceleration controls the spectral evolution which follows a soft-hard-soft pattern. Furthermore, a pivot point (that is, a common crossing point of the accelerated particle spectra at different times) is found at around 10 keV. It can be brought into agreement with the observed value of 20 keV by enhanced trapping through an electric potential. Conclusions: The model proposed here accounts for the key features observed in the spectral evolution of hard X-ray emission from looptop sources.

  15. A Fourier-spectral element algorithm for thermal convection in rotating axisymmetric containers

    E-Print Network [OSTI]

    Fournier, Alexandre

    A Fourier-spectral element algorithm for thermal convection in rotating axisymmetric containers Abstract We present a Fourier-spectral element approach for modeling thermal convection in a rotating, Spectral Methods for Axisymmetric Domains, Gauthier-Villars, Paris, 1999], a Fourier expansion of the field

  16. Accepted Applied Optics, May 2001 Thermal Infrared Spectral Band Detection Limits for

    E-Print Network [OSTI]

    Kirkland, Laurel

    for in the remotely sensed spectral data base. Second, since the spectral shape varies with particle size, weathering kirkland@lpi.usra.edu. K. Herr is with The Aerospace Corporation, Los Angeles, California, 90009. J; revised manuscript received 3 April 2001. examined detection limits based on spectral signature mapping

  17. Spectral properties of the post-merger gravitational-wave signal from binary neutron stars

    E-Print Network [OSTI]

    Kentaro Takami; Luciano Rezzolla; Luca Baiotti

    2015-03-06

    Extending previous work by a number of authors, we have recently presented a new approach in which the detection of gravitational waves from merging neutron star binaries can be used to determine the equation of state of matter at nuclear density and hence the structure of neutron stars. In particular, after performing a large number of numerical-relativity simulations of binaries with nuclear equations of state, we have found that the post-merger emission is characterized by two distinct and robust spectral features. While the high-frequency peak was already shown to be associated with the oscillations of the hypermassive neutron star produced by the merger and to depend on the equation of state, we have highlighted that the low-frequency peak is related to the merger process and to the total compactness of the stars in the binary. This relation is essentially universal and provides a powerful tool to set tight constraints on the equation of state. We here provide additional information on the extensive analysis performed, illustrating the methods used, the tests considered, as well as the robustness of the results. We also discuss additional relations that can be deduced when exploring the data and how these correlate with various properties of the binary. Finally, we present a simple mechanical toy model that explains the main spectral features of the post-merger signal and can even reproduce analytically the complex waveforms emitted right after the merger.

  18. New Positron Spectral Features from Supersymmetric Dark Matter - a Way to Explain the PAMELA Data?

    E-Print Network [OSTI]

    Lars Bergstrom; Torsten Bringmann; Joakim Edsjo

    2008-11-13

    The space-borne antimatter experiment PAMELA has recently reported a surprising rise in the positron to electron ratio at high energies. It has also recently been found that electromagnetic radiative corrections in some cases may boost the gamma-ray yield from supersymmetric dark matter annihilations in the galactic halo by up to three or four orders of magnitude, providing distinct spectral signatures for indirect dark matter searches to look for. Here, we investigate whether the same type of corrections can also lead to sizeable enhancements in the positron yield. We find that this is indeed the case, albeit for a smaller region of parameter space than for gamma rays; selecting models with a small mass difference between the neutralino and sleptons, like in the stau coannihilation region in mSUGRA, the effect becomes more pronounced. The resulting, rather hard positron spectrum with a relatively sharp cutoff may potentially fit the rising positron ratio measured by the PAMELA satellite. To do so, however, very large "boost factors" have to be invoked that are not expected in current models of halo structure. If the predicted cutoff would also be confirmed by later PAMELA data or upcoming experiments, one could either assume non-thermal production in the early universe or non-standard halo formation to explain such a spectral feature as an effect of dark matter annihilation. At the end of the paper, we briefly comment on the impact of radiative corrections on other annihilation channels, in particular antiprotons and neutrinos.

  19. New positron spectral features from supersymmetric dark matter: A way to explain the PAMELA data?

    SciTech Connect (OSTI)

    Bergstroem, Lars; Bringmann, Torsten; Edsjoe, Joakim

    2008-11-15

    The space-borne antimatter experiment PAMELA has recently reported a surprising rise in the positron to electron ratio at high energies. It has also recently been found that electromagnetic radiative corrections in some cases may boost the gamma-ray yield from supersymmetric dark-matter annihilations in the galactic halo by up to 3 or 4 orders of magnitude, providing distinct spectral signatures for indirect dark matter searches to look for. Here, we investigate whether the same type of corrections can also lead to sizeable enhancements in the positron yield. We find that this is indeed the case, albeit for a smaller region of parameter space than for gamma rays; selecting models with a small mass difference between the neutralino and sleptons, like in the stau-coannihilation region in mSUGRA, the effect becomes more pronounced. The resulting, rather hard positron spectrum with a relatively sharp cutoff may potentially fit the rising positron ratio measured by the PAMELA satellite. To do so, however, very large 'boost factors' have to be invoked that are not expected in current models of halo structure. If the predicted cutoff would also be confirmed by later PAMELA data or upcoming experiments, one could either assume nonthermal production in the early universe or nonstandard halo formation to explain such a spectral feature as an effect of dark-matter annihilation. At the end of the paper, we briefly comment on the impact of radiative corrections on other annihilation channels, in particular, antiprotons and neutrinos.

  20. Spectral Study of the Galactic Ridge X-ray Emission with Suzaku

    E-Print Network [OSTI]

    Ebisawa, Ken; Tanaka, Yasuo; Koyama, Katsuji; Ezoe, Yuichiro; Bamba, Aya; Kokubun, Motohide; Hyodo, Yoshiaki; Tsujimoto, Masahiro; Takahashi, Hiromitsu

    2007-01-01

    We have observed a typical Galactic plane field at (l,b) = (28.46d, -0.20d) with Suzaku for 100 ksec to carry out a precise spectral study of the Galactic Ridge X-ray Emission (GRXE). The field is known to be devoid of X-ray point sources brighter than ~2 x 10^{-13} ergs s^{-1} cm^{-2} (2--10 keV), and already deeply observed with Chandra. Thanks to the low and stable background and high spectral resolution of Suzaku, we were able to resolve, for the first time, three narrow iron K-emission lines from low-ionized (6.41 keV), helium-like (6.67 keV), and hydrogenic ions (7.00 keV) in the GRXE spectrum. These line features constrain the GRXE emission mechanisms: The cosmic-ray ion charge exchange model or the non-equilibrium ionization plasma model are unlikely, since they require either broad emission lines or lines at intermediate ionization states. Collisional ionization equilibrium plasma is the likely origin for the 6.67 keV and 7.00 keV lines, while origin of the 6.41 keV line, which is due to fluorescence...

  1. Multi-Spectral imaging of vegetation for detecting CO2 leaking from underground

    SciTech Connect (OSTI)

    Rouse, J.H.; Shaw, J.A.; Lawrence, R.L.; Lewicki, J.L.; Dobeck, L.M.; Repasky, K.S.; Spangler, L.H.

    2010-06-01

    Practical geologic CO{sub 2} sequestration will require long-term monitoring for detection of possible leakage back into the atmosphere. One potential monitoring method is multi-spectral imaging of vegetation reflectance to detect leakage through CO{sub 2}-induced plant stress. A multi-spectral imaging system was used to simultaneously record green, red, and near-infrared (NIR) images with a real-time reflectance calibration from a 3-m tall platform, viewing vegetation near shallow subsurface CO{sub 2} releases during summers 2007 and 2008 at the Zero Emissions Research and Technology field site in Bozeman, Montana. Regression analysis of the band reflectances and the Normalized Difference Vegetation Index with time shows significant correlation with distance from the CO{sub 2} well, indicating the viability of this method to monitor for CO{sub 2} leakage. The 2007 data show rapid plant vigor degradation at high CO{sub 2} levels next to the well and slight nourishment at lower, but above-background CO{sub 2} concentrations. Results from the second year also show that the stress response of vegetation is strongly linked to the CO{sub 2} sink-source relationship and vegetation density. The data also show short-term effects of rain and hail. The real-time calibrated imaging system successfully obtained data in an autonomous mode during all sky and daytime illumination conditions.

  2. Note: Spectral motional Stark effect diagnostic for measurement of magnetic fields below 0.3 T

    SciTech Connect (OSTI)

    Lizunov, A.; Donin, A. [Budker Institute of Nuclear Physics, 630090 Novosibirsk (Russian Federation) [Budker Institute of Nuclear Physics, 630090 Novosibirsk (Russian Federation); Novosibirsk State University, 630090 Novosibirsk (Russian Federation); Savkin, V. [Budker Institute of Nuclear Physics, 630090 Novosibirsk (Russian Federation)] [Budker Institute of Nuclear Physics, 630090 Novosibirsk (Russian Federation)

    2013-08-15

    The paper reports on development of the spectral motional Stark effect (MSE) diagnostic in the midplane of the gas dynamic trap (GDT) linear system for magnetic confinement of anisotropic hot-ion plasma. The axially symmetric GDT vacuum magnetic field has a minimum value in the midplane, which varies from 0.2 to 0.35 T in different regimes of operation. Buildup of 15 keV ion population generates a diamagnetic reduction of magnetic field in the plasma core of up to 30% in the maximum density region, as measured by the existing eight-line MSE diagnostic. Commissioning of the midplane MSE provided first direct measurements of diamagnetic modifications in the minimum magnetic field GDT section, a necessary complement to the understanding of equilibrium and self-organization of high-? plasmas in GDT. Making use of the stable short-pulse diagnostic beam and calibration of the apparent spectral width of beam emission lines allow for the measurement of the plasma magnetic field of 0.29 ± 0.007 T with the integration time of 200 ?s.

  3. Short time scale thermal mechanical shock wave propagation in high performance microelectronic packaging configuration 

    E-Print Network [OSTI]

    Nagaraj, Mahavir

    2004-11-15

    The generalized theory of thermoelasticity was employed to characterize the coupled thermal and mechanical wave propagation in high performance microelectronic packages. Application of a Gaussian heat source of spectral profile similar to high...

  4. Analyzing source apportioned methane in northern California during Discover-AQ-CA using airborne measurements and model simulations

    SciTech Connect (OSTI)

    Johnson, Matthew S.; Yates, Emma L.; Iraci, Laura T.; Loewenstein, Max; Tadi?, Jovan M.; Wecht, Kevin J.; Jeong, Seongeun; Fischer, Marc L.

    2014-12-01

    This study analyzes source apportioned methane (CH4) emissions and atmospheric mixing ratios in northern California during the Discover-AQ-CA field campaign using airborne measurement data and model simulations. Source apportioned CH4 emissions from the Emissions Database for Global Atmospheric Research (EDGAR) version 4.2 were applied in the 3-D chemical transport model GEOS-Chem and analyzed using airborne measurements taken as part of the Alpha Jet Atmospheric eXperiment over the San Francisco Bay Area (SFBA) and northern San Joaquin Valley (SJV). During the time period of the Discover-AQ-CA field campaign EDGAR inventory CH4 emissions were ~5.30 Gg day –1 (Gg = 1.0 × 109 g) (equating to ~1.90 × 103 Gg yr–1) for all of California. According to EDGAR, the SFBA and northern SJV region contributes ~30% of total CH4 emissions from California. Source apportionment analysis during this study shows that CH4 mixing ratios over this area of northern California are largely influenced by global emissions from wetlands and local/global emissions from gas and oil production and distribution, waste treatment processes, and livestock management. Model simulations, using EDGAR emissions, suggest that the model under-estimates CH4 mixing ratios in northern California (average normalized mean bias (NMB) = –5.2% and linear regression slope = 0.20). The largest negative biases in the model were calculated on days when large amounts of CH4 were measured over local emission sources and atmospheric CH4 mixing ratios reached values >2.5 parts per million. Sensitivity emission studies conducted during this research suggest that local emissions of CH4 from livestock management processes are likely the primary source of the negative model bias. These results indicate that a variety, and larger quantity, of measurement data needs to be obtained and additional research is necessary to better quantify source apportioned CH4 emissions in California.

  5. Optical trapping and rotation of airborne absorbing particles with a single focused laser beam

    SciTech Connect (OSTI)

    Lin, Jinda; Li, Yong-qing, E-mail: liy@ecu.edu [Department of Physics, East Carolina University, Greenville, North Carolina 27858-4353 (United States)] [Department of Physics, East Carolina University, Greenville, North Carolina 27858-4353 (United States)

    2014-03-10

    We measure the periodic circular motion of single absorbing aerosol particles that are optically trapped with a single focused Gaussian beam and rotate around the laser propagation direction. The scattered light from the trapped particle is observed to be directional and change periodically at 0.4–20?kHz. The instantaneous positions of the moving particle within a rotation period are measured by a high-speed imaging technique using a charge coupled device camera and a repetitively pulsed light-emitting diode illumination. The centripetal acceleration of the trapped particle as high as ?20 times the gravitational acceleration is observed and is attributed to the photophoretic forces.

  6. Bistatic receiver model for airborne lidar returns incident on an imaging array from underwater objects

    E-Print Network [OSTI]

    Singer, Andrew C

    returns from the surrounding water medium and ocean bottom. Our results provide a generalization ocean lidar return, obtained by a CCD array. © 2002 Optical Society of America OCIS codes: 010.3640, 030 a laser to generate a short, high-powered pulse of light. The transmitted laser beam can penetrate the air

  7. A glacier inventory for South Tyrol, Italy, based on airborne laser-scanner data

    E-Print Network [OSTI]

    Kerschner, Hanns

    and equilibrium- line altitude. A reduction of 32% was observed in glacier area from 1983 to 2006. Volume change-skiing resorts, mountaineering), for agriculture (irrigation) and for the production of hydropower). Guidelines of applications (Arnold and others, 2006). The method is characterized by a high degree of automation, in terms

  8. Spectral calibration in the mid-infrared: Challenges and solutions

    SciTech Connect (OSTI)

    Sloan, G. C. [Cornell University, Center for Radiophysics and Space Research, Ithaca, NY 14853-6801 (United States); Herter, T. L.; Houck, J. R. [Cornell University, Astronomy Department, Ithaca, NY 14853-6801 (United States); Charmandaris, V. [Department of Physics and ITCP, University of Crete, GR-71003, Heraklion (Greece); Sheth, K. [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903 (United States); Burgdorf, M., E-mail: sloan@isc.astro.cornell.edu [HE Space Operations, Flughafenallee 24, D-28199 Bremen (Germany)

    2015-01-01

    We present spectra obtained with the Infrared Spectrograph on the Spitzer Space Telescope of 33 K giants and 20 A dwarfs to assess their suitability as spectrophotometric standard stars. The K giants confirm previous findings that the strength of the SiO absorption band at 8 ?m increases for both later optical spectral classes and redder (B–V){sub 0} colors, but with considerable scatter. For K giants, the synthetic spectra underpredict the strengths of the molecular bands from SiO and OH. For these reasons, the assumed true spectra for K giants should be based on the assumption that molecular band strengths in the infrared can be predicted accurately from neither optical spectral class or color nor synthetric spectra. The OH bands in K giants grow stronger with cooler stellar temperatures, and they are stronger than predicted by synthetic spectra. As a group, A dwarfs are better behaved and more predictable than the K giants, but they are more likely to show red excesses from debris disks. No suitable A dwarfs were located in parts of the sky continuously observable from Spitzer, and with previous means of estimating the true spectra of K giants ruled out, it was necessary to use models of A dwarfs to calibrate spectra of K giants from observed spectral ratios of the two groups and then use the calibrated K giants as standards for the full database of infrared spectra from Spitzer. We also describe a lingering artifact that affects the spectra of faint blue sources at 24 ?m.

  9. Hamiltonian spectral invariants, symplectic spinors and Frobenius structures I

    E-Print Network [OSTI]

    Andreas Klein

    2015-08-26

    This is the first of two articles aiming to introduce symplectic spinors into the field of symplectic topology and the subject of Frobenius structures. After exhibiting a (tentative) axiomating setting for Frobenius structures resp. 'Higgs pairs' in the context of symplectic spinors, we present immediate observations concerning a local Schroedinger equation, the first structure connection and the existence of 'spectrum', its topological interpretation and its connection to 'formality' which are valid for the case of standard Frobenius structures. We give a classification of the irreducibles and the indecomposables of the latter in terms of certain $U(n)$-reductions of the $G$-extension of the metaplectic frame bundle and a certain connection on it, where $G$ is the semi-direct product of the metaplectic group and the Heisenberg group, while the indecomposable case involves in addition the combinatorial structure of the eigenstates of the $n$-dimensional harmonic oscillator. In the second part, we associate an irreducible Frobenius structure to any Hamiltonian diffeomorphism $\\Phi$ on a cotangent bundle $T^*M$. The spectral Lagrangian in $T^*(T^*M)$ associated to this Frobenius structure intersects the zero-section $T^*M$ exactly at the fixed points of $\\Phi$. We give lower bounds for the number of fixed points of $\\Phi$ by defining a $C^*$-valued function on $T^*\\tilde M$ defined by matrix coeficients of the Heisenberg group acting on spinors, where $\\tilde M$ is a certain 'complexification' of $M$, whose critical points are in bijection to the fixed points of $\\Phi$ resp. to the intersection of the spectral Lagrangian with the zero section $T^*\\tilde M$. We discuss how to define spectral invariants in the sense of Viterbo and Oh by lifting the above function to a real-valued function on an appropriate cyclic covering of $T^*\\tilde M$ and using minimax-methods for 'half-infinite' chains.

  10. Spectral Modeling of SNe Ia Near Maximum Light: Probing the Characteristics of Hydro Models

    E-Print Network [OSTI]

    E. Baron; S. Bongard; David Branch; Peter H. Hauschildt

    2006-03-03

    We have performed detailed NLTE spectral synthesis modeling of 2 types of 1-D hydro models: the very highly parameterized deflagration model W7, and two delayed detonation models. We find that overall both models do about equally well at fitting well observed SNe Ia near to maximum light. However, the Si II 6150 feature of W7 is systematically too fast, whereas for the delayed detonation models it is also somewhat too fast, but significantly better than that of W7. We find that a parameterized mixed model does the best job of reproducing the Si II 6150 line near maximum light and we study the differences in the models that lead to better fits to normal SNe Ia. We discuss what is required of a hydro model to fit the spectra of observed SNe Ia near maximum light.

  11. Single-Beam Coherent Raman Spectroscopy and Microscopy via Spectral Notch Shaping

    E-Print Network [OSTI]

    Katz, Ori; Grinvald, Eran; Silberberg, Yaron

    2010-01-01

    Raman spectroscopy is one of the key techniques in the study of vibrational modes and molecular structures. In Coherent Anti-Stokes Raman Scattering (CARS) spectroscopy, a molecular vibrational spectrum is resolved via the third-order nonlinear interaction of pump, Stokes and probe photons, typically using a complex experimental setup with multiple beams and laser sources. Although CARS has become a widespread technique for label-free chemical imaging and detection of contaminants, its multi-source, multi-beam experimental implementation is challenging. In this work we present a simple and easily implementable scheme for performing single-beam CARS spectroscopy and microscopy using a single femtosecond pulse, shaped by a tunable narrowband notch filter. As a substitute for multiple sources, the single broadband pulse simultaneously provides the pump, Stokes and probe photons, exciting a broad band of vibrational levels. High spectroscopic resolution is obtained by utilizing a tunable spectral notch, shaped wi...

  12. Spectral Features of Magnetic Fluctuations at Proton Scales from Fast to Slow Solar Wind

    E-Print Network [OSTI]

    Bruno, R

    2015-01-01

    This Letter investigates the spectral characteristics of the interplanetary magnetic field fluctuations at proton scales during several time intervals chosen along the speed profile of a fast stream. The character of the fluctuations within the first frequency decade, beyond the high frequency break located between the fluid and the kinetic regime, strongly depends on the type of wind. While the fast wind shows a clear signature of both right handed and left handed polarized fluctuations, possibly associated with KAW and Ion-Cyclotron waves, respectively, the rarefaction region, where the wind speed and the Alfv\\'{e}nicity of low frequency fluctuations decrease, shows a rapid disappearance of the ion-cyclotron signature followed by a more gradual disappearance of the KAWs. Moreover, also the power associated to perpendicular and parallel fluctuations experiences a rapid depletion, keeping, however, the power anisotropy in favour of the perpendicular spectrum.

  13. Spectral Linewidth Narrowing and Tunable Two-Color Laser Operation of Two Diode Laser Arrays

    SciTech Connect (OSTI)

    Liu, Bo [ORNL; Braiman, Yehuda [ORNL

    2012-01-01

    We propose and implement a common external cavity to narrow spectral linewidth of two broad-area laser diode arrays (LDAs) and align their center wavelengths. The locked center wavelength of two LDAs can be tuned in the range of {approx}10 nm by tuning the tilted angle of the diffraction grating. The output beams of two LDAs are spatially overlapped through the polarization beam splitter of the common external cavity, and the total output power equals the power of two LDAs. The center wavelength of each LDA can be independently tuned by shifting the corresponding fast-axis collimation lens. As a result, the high-power two-color LDA operation is demonstrated with the tunable wavelength difference of up to 2 nm ({approx}1 THz).

  14. Final Report DE-EE0005380: Assessment of Offshore Wind Farm Effects on Sea Surface, Subsurface and Airborne Electronic Systems

    SciTech Connect (OSTI)

    Ling, Hao; Hamilton, Mark F.; Bhalla, Rajan; Brown, Walter E.; Hay, Todd A.; Whitelonis, Nicholas J.; Yang, Shang-Te; Naqvi, Aale R.

    2013-09-30

    Offshore wind energy is a valuable resource that can provide a significant boost to the US renewable energy portfolio. A current constraint to the development of offshore wind farms is the potential for interference to be caused by large wind farms on existing electronic and acoustical equipment such as radar and sonar systems for surveillance, navigation and communications. The US Department of Energy funded this study as an objective assessment of possible interference to various types of equipment operating in the marine environment where offshore wind farms could be installed. The objective of this project was to conduct a baseline evaluation of electromagnetic and acoustical challenges to sea surface, subsurface and airborne electronic systems presented by offshore wind farms. To accomplish this goal, the following tasks were carried out: (1) survey electronic systems that can potentially be impacted by large offshore wind farms, and identify impact assessment studies and research and development activities both within and outside the US, (2) engage key stakeholders to identify their possible concerns and operating requirements, (3) conduct first-principle modeling on the interactions of electromagnetic signals with, and the radiation of underwater acoustic signals from, offshore wind farms to evaluate the effect of such interactions on electronic systems, and (4) provide impact assessments, recommend mitigation methods, prioritize future research directions, and disseminate project findings. This report provides a detailed description of the methodologies used to carry out the study, key findings of the study, and a list of recommendations derived based the findings.

  15. Thermal, chemical and spectral equilibration in heavy-ion collisions

    E-Print Network [OSTI]

    Gábor András Almási; György Wolf

    2014-07-08

    We have considered the equilibration in a relativistic heavy ion collision using our transport model. We applied periodic boundary conditions to close the system in a box. We found that the thermal equilibration takes place in the first 20-40 fm/c which time is comparable to the duration of a heavy ion collision. The chemical equilibration is a much slower process and the system does not equilibrate in a heavy ion collision. We have also shown that the mass spectra of broad resonances immediately follows their in-medium spectral functions.

  16. Spectral regularisation: induced gravity and the onset of inflation

    SciTech Connect (OSTI)

    Kurkov, Max A.; Sakellariadou, Mairi E-mail: mairi.sakellariadou@kcl.ac.uk

    2014-01-01

    Using spectral regularisation, we compute the Weyl anomaly and express the anomaly generating functional of the quantum effective action through a collective scalar degree of freedom of all quantum vacuum fluctuations. Such a formulation allows us to describe induced gravity on an equal footing with the anomaly-induced effective action, in a self-consistent way. We then show that requiring stability of the cosmological constant under loop quantum corrections, Sakharov's induced gravity and Starobinsky's anomaly-induced inflation are either both present or both absent, depending on the particle content of the theory.

  17. Smearing of Observables and Spectral Measures on Quantum Structures

    E-Print Network [OSTI]

    Anatolij Dvure?enskij

    2012-04-29

    An observable on a quantum structure is any $\\sigma$-homomorphism of quantum structures from the Borel $\\sigma$-algebra of the real line into the quantum structure which is in our case a monotone $\\sigma$-complete effect algebras with the Riesz Decomposition Property. We show that every observable is a smearing of a sharp observable which takes values from a Boolean $\\sigma$-subalgebra of the effect algebra, and we prove that for every element of the effect algebra there is its spectral measure.

  18. Noncommutative geometry, Grand Symmetry and twisted spectral triple

    E-Print Network [OSTI]

    Agostino Devastato

    2015-03-09

    In the noncommutative geometry approach to the standard model we discuss the possibility to derive the extra scalar field sv- initially suggested by particle physicist to stabilize the electroweak vacuum - from a "grand algebra" that contains the usual standard model algebra. We introduce the Connes-Moscovici twisted spectral triples for the Grand Symmetry model, to cure a technical problem, that is the appearance, together with the field sv, of unbounded vectorial terms. The twist makes these terms bounded, and also permits to understand the breaking making the computation of the Higgs mass compatible with the 126 GeV experimental value.

  19. Spectral Structure of Electron Antineutrinos from Nuclear Reactors

    E-Print Network [OSTI]

    D. A. Dwyer; T. J. Langford

    2014-07-04

    Recent measurements of the positron energy spectrum obtained from inverse beta decay interactions of reactor electron antineutrinos show an excess in the 4 to 6 MeV region relative to current predictions. First-principle calculations of fission and beta decay processes within a typical pressurized water reactor core identify prominent fission daughter isotopes as a possible origin for this excess. These calculations also predict percent-level substructure in the antineutrino spectrum due to Coulomb effects in beta decay. Precise measurement of this substructure can constrain nuclear reactor physics. The substructure can be a systematic uncertainty for measurements utilizing the detailed spectral shape.

  20. Spectral triples from bimodule connections and Chern connections

    E-Print Network [OSTI]

    Edwin Beggs; Shahn Majid

    2015-09-03

    We give a geometrical construction of Connes spectral triples or noncommutative Dirac operators $D$ starting with a bimodule connection on the proposed spinor bundle. The theory is applied to the example of $M_2(\\Bbb C)$, and also applies to the standard $q$-sphere and the $q$-disk with the right classical limit and all properties holding except for $\\mathcal J$ now being a twisted isometry. We also describe a noncommutative Chern construction from holomorphic bundles which in the $q$-sphere case provides the relevant bimodule connection.