National Library of Energy BETA

Sample records for acrf pyrgeometer blackbody

  1. Absolute cavity pyrgeometer

    DOE Patents [OSTI]

    Reda, Ibrahim

    2013-10-29

    Implementations of the present disclosure involve an apparatus and method to measure the long-wave irradiance of the atmosphere or long-wave source. The apparatus may involve a thermopile, a concentrator and temperature controller. The incoming long-wave irradiance may be reflected from the concentrator to a thermopile receiver located at the bottom of the concentrator to receive the reflected long-wave irradiance. In addition, the thermopile may be thermally connected to a temperature controller to control the device temperature. Through use of the apparatus, the long-wave irradiance of the atmosphere may be calculated from several measurements provided by the apparatus. In addition, the apparatus may provide an international standard of pyrgeometers' calibration that is traceable back to the International System of Units (SI) rather than to a blackbody atmospheric simulator.

  2. Calibrating Pyrgeometers Outdoors Independent from the Reference Value of the Atmospheric Longwave Irradiance

    SciTech Connect (OSTI)

    Reda, I.; Hickey, J. R.; Grobner, J.; Andreas, A.; Stoffel, T.

    2006-08-01

    In this article, we describe a method for the calibration of thermopile pyrgeometers in the absence of a reference for measurement of atmospheric longwave irradiance. This is referred to as the incoming longwave irradiance in this article. The method is based on an indoor calibration using a low-temperature blackbody source to obtain the calibration coefficients that determine the pyrgeometer's radiation characteristics. From these coefficients the outgoing irradiance of the pyrgeometer can be calculated. The pyrgeometer is then installed outdoors on an aluminum plate that is connected to a circulating temperature bath. By adjusting the temperature bath to the approximate value of the effective sky temperature, the pyrgeometer's body temperature is lowered changing the pyrgeometer's thermopile output. If the incoming longwave irradiance is stable, the slope of the outgoing irradiance versus the pyrgeometer's thermopile output is the outdoor net irradiance responsivity (RSnet), independent of the absolute value of the atmospheric longwave irradiance. The indoor calibration coefficients and the outdoor RSnet are then used in the pyrgeometer equation to calculate the incoming longwave irradiance. To evaluate this method, the calculated irradiance using the derived coefficients was compared to the irradiance measured using a pyrgeometer with direct traceability to the World Infrared Standard Group (WISG). This is maintained at the Physikalisch-Meteorologisches Observatorium Davos, World Radiation Center, Switzerland. Based on results from four pyrgeometers calibrations, this method suggests measurement agreement with the WISG to within +/- 3 W/m2 for all sky conditions.

  3. Introducing an Absolute Cavity Pyrgeometer for Improving the Atmospheric Longwave Irradiance Measurement (Presentation)

    SciTech Connect (OSTI)

    Reda, I.; Hansen, L.; Zeng, J.

    2012-08-01

    Advancing climate change research requires accurate and traceable measurement of the atmospheric longwave irradiance. Current measurement capabilities are limited to an estimated uncertainty of larger than +/- 4 W/m2 using the interim World Infrared Standard Group (WISG). WISG is traceable to the Systeme international d'unites (SI) through blackbody calibrations. An Absolute Cavity Pyrgeometer (ACP) is being developed to measure absolute outdoor longwave irradiance with traceability to SI using the temperature scale (ITS-90) and the sky as the reference source, instead of a blackbody. The ACP was designed by NREL and optically characterized by the National Institute of Standards and Technology (NIST). Under clear-sky and stable conditions, the responsivity of the ACP is determined by lowering the temperature of the cavity and calculating the rate of change of the thermopile output voltage versus the changing net irradiance. The absolute atmospheric longwave irradiance is then calculated with an uncertainty of +/- 3.96 W/m2 with traceability to SI. The measured irradiance by the ACP was compared with the irradiance measured by two pyrgeometers calibrated by the World Radiation Center with traceability to the WISG. A total of 408 readings was collected over three different clear nights. The calculated irradiance measured by the ACP was 1.5 W/m2 lower than that measured by the two pyrgeometers that are traceable to WISG. Further development and characterization of the ACP might contribute to the effort of improving the uncertainty and traceability of WISG to SI.

  4. Evaluation of Improved Pyrgeometer Calibration Method

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

    Improved Pyrgeometer Calibration Method I. Reda, P. A. Gotseff, T. L. Stoffel, and C. Webb National Renewable Energy Laboratory Golden, Colorado Abstract Broadband longwave (atmospheric) irradiance measurements are important for determining the earth's total energy balance. The Atmospheric Radiation Measurement (ARM) Program has deployed more than 50 pyrgeometers for measuring the upwelling and downwelling longwave irradiance as part of Solar Infrared Station (SIRS), SKYRAD, and GNDRAD

  5. Uncertainty Estimates for SIRS, SKYRAD, & GNDRAD Data and Reprocessing the Pyrgeometer Data (Presentation)

    SciTech Connect (OSTI)

    Reda, I.; Stoffel, T.; Habte, A.

    2014-03-01

    The National Renewable Energy Laboratory (NREL) and the Atmospheric Radiation Measurement (ARM) Climate Research Facility work together in providing data from strategically located in situ measurement observatories around the world. Both work together in improving and developing new technologies that assist in acquiring high quality radiometric data. In this presentation we summarize the uncertainty estimates of the ARM data collected at the ARM Solar Infrared Radiation Station (SIRS), Sky Radiometers on Stand for Downwelling Radiation (SKYRAD), and Ground Radiometers on Stand for Upwelling Radiation (GNDRAD), which ultimately improve the existing radiometric data. Three studies are also included to show the difference between calibrating pyrgeometers (e.g., Eppley PIR) using the manufacturer blackbody versus the interim World Infrared Standard Group (WISG), a pyrgeometer aging study, and the sampling rate effect of correcting historical data.

  6. AC/RF Superconductivity

    SciTech Connect (OSTI)

    Ciovati, Gianluigi

    2015-02-01

    This contribution provides a brief introduction to AC/RF superconductivity, with an emphasis on application to accelerators. The topics covered include the surface impedance of normal conductors and superconductors, the residual resistance, the field dependence of the surface resistance, and the superheating field.

  7. Introducing an Absolute Cavity Pyrgeometer (ACP) for Improving the Atmospheric Longwave Irradiance Measurement (Poster)

    SciTech Connect (OSTI)

    Reda, I.; Stoffel, T.

    2012-03-01

    Advancing climate change research requires accurate and traceable measurement of the atmospheric longwave irradiance. Current measurement capabilities are limited to an estimated uncertainty of larger than +/- 4 W/m2 using the interim World Infrared Standard Group (WISG). WISG is traceable to the Systeme international d'unites (SI) through blackbody calibrations. An Absolute Cavity Pyrgeometer (ACP) is being developed to measure absolute outdoor longwave irradiance with traceability to SI using the temperature scale (ITS-90) and the sky as the reference source, instead of a blackbody. The ACP was designed by NREL and optically characterized by the National Institute of Standards and Technology (NIST). Under clear-sky and stable conditions, the responsivity of the ACP is determined by lowering the temperature of the cavity and calculating the rate of change of the thermopile output voltage versus the changing net irradiance. The absolute atmospheric longwave irradiance is then calculated with an uncertainty of +/- 3.96 W/m2 with traceability to SI. The measured irradiance by the ACP was compared with the irradiance measured by two pyrgeometers calibrated by the World Radiation Center with traceability to the WISG.

  8. AMIE (ACRF MJO Investigation Experiment)

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

    AMIE (ACRF MJO Investigation Experiment) Planning Meeting AMIE Science Steering Committee Chuck Long, Tony DelGenio, Bill Gustafson, Bob Houze, Mike Jensen, Steve Klein, Ruby...

  9. Microsoft PowerPoint - ARM_pyrgeometer.ppt

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

    Pyrgeometer Calibrations & Field Measurements Information Regarding the Data Restriction Notice Tom Stoffel 7 December 2005 ARM-05-111 2 Outline * Why the need for longwave data restriction? - Important Considerations and the 12 Wm -2 longwave results problem * What ARM data are effected? - List of station-dates * Can the data be adjusted? - Using available 20-sec data samples * How is ARM addressing pyrgeometer calibration? - In search of a measurement reference * References * Acronyms *

  10. ACRF Newsletter_May_FINAL

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

    CHANGE STUDIES FOR TEACHERS AND STUDENTS The Department of Energy's Atmospheric Radiation Measurement (ARM) Climate Research Facility supports education and outreach efforts for communities and schools located near its sites. The mission of the Education and Outreach Program is to promote basic science education and community awareness of climate change research by focusing on three goals: student enrichment, teacher support, and community outreach. http://education.arm.gov/ ACRF Education and

  11. MEASURING TEMPORAL PHOTON BUNCHING IN BLACKBODY RADIATION

    SciTech Connect (OSTI)

    Tan, P. K.; Poh, H. S.; Kurtsiefer, C.; Yeo, G. H.; Chan, A. H. E-mail: phyck@nus.edu.sg

    2014-07-01

    Light from thermal blackbody radiators such as stars exhibits photon bunching behavior at sufficiently short timescales. However, with available detector bandwidths, this bunching signal is difficult to observe directly. We present an experimental technique to increase the photon bunching signal in blackbody radiation via spectral filtering of the light source. Our measurements reveal strong temporal photon bunching from blackbody radiation, including the Sun. This technique allows for an absolute measurement of the photon bunching signature g {sup (2)}(0), and thereby a direct statement on the statistical nature of a light source. Such filtering techniques may help revive the interest in intensity interferometry as a tool in astronomy.

  12. ACRF Ingest Software Status: New, Current, and Future - June 2008

    SciTech Connect (OSTI)

    AS Koontz; S Choudhury; BD Ermold; NN Keck; KL Gaustad; RC Perez

    2008-06-01

    The purpose of this report is to provide status of the ingest software used to process instrument data for the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF). The report is divided into 4 sections: (1) for news about ingests currently under development, (2) for current production ingests, (3) for future ingest development plans, and (4) for information on retired ingests. Please note that datastreams beginning in “xxx” indicate cases where ingests run at multiple ACRF sites, which results in a datastream(s) for each location.

  13. ACRF Ingest Software Status: New, Current, and Future - May 2008

    SciTech Connect (OSTI)

    AS Koontz; S Choudhury; BD Ermold; N N Keck; KL Gaustad; RC Perez

    2008-05-01

    The purpose of this report is to provide status of the ingest software used to process instrument data for the Atmospheric Radiation Measurement Program Climate Research Facility (ACRF). The report is divided into 4 sections: (1) for news about ingests currently under development, (2) for current production ingests, (3) for future ingest development plans, and (4) for information on retired ingests. Please note that datastreams beginning in “xxx” indicate cases where ingests run at multiple ACRF sites, which results in a datastream(s) for each location.

  14. ACRF Ingest Software Status: New, Current, and Future (September 2007)

    SciTech Connect (OSTI)

    Koontz, AS; Choudhury, S; Ermold, BD; Gaustad, KL

    2007-04-01

    The purpose of this report is to provide status of the ingest software used to process instrument data for the Atmospheric Radiation Measurement Program Climate Research Facility (ACRF). The report is divided into 4 sections: (1) for news about ingests currently under development, (2) for current production ingests, (3) for future ingest development plans, and (4) for information on retired ingests. Please note that datastreams beginning in “xxx” indicate cases where ingests run at multiple ACRF sites, which results in a datastream(s) for each location.

  15. ACRF Ingest Software Status: New, Current, and Future - April 2008

    SciTech Connect (OSTI)

    AS Koontz; S Choudhury; BD Ermold; NN Keck; KL Gaustad; RC Perez

    2008-04-01

    The purpose of this report is to provide status of the ingest software used to process instrument data for the Atmospheric Radiation Measurement Program Climate Research Facility (ACRF). The report is divided into 4 sections: (1) for news about ingests currently under development, (2) for current production ingests, (3) for future ingest development plans, and (4) for information on retired ingests. Please note that datastreams beginning in “xxx” indicate cases where ingests run at multiple ACRF sites, which results in a datastream(s) for each location.

  16. ACRF Ingest Software Status: New, Current, and Future - March 2008

    SciTech Connect (OSTI)

    AS Koontz; S Choudhury; BD Ermold; NN Keck; KL Gaustad; RC Perez

    2008-03-01

    The purpose of this report is to provide status of the ingest software used to process instrument data for the Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF). The report is divided into four sections: (1) news about ingests currently under development, (2) current production ingests, (3) future ingest development plans, and (4) information on retired ingests. Please note that datastreams beginning in “xxx” indicate cases where ingests run at multiple ACRF sites, which results in a datastream(s) for each location.

  17. ACRF Instrumentation Status: New, Current, and Future - January 2008

    SciTech Connect (OSTI)

    AS Koontz; S Choudhury; BD Ermold; KL Gaustad

    2008-01-31

    The purpose of this report is to provide status of the ingest software used to process instrument data for the Atmospheric Radiation Measurement Program Climate Research Facility (ACRF). The report is divided into 4 sections: (1) for news about ingests currently under development, (2) for current production ingests, (3) for future ingest development plans, and (4) for information on retired ingests. Please note that datastreams beginning in “xxx” indicate cases where ingests run at multiple ACRF sites, which results in a datastream(s) for each location.

  18. ACRF Ingest Software Status: New, Current, and Future (November 2007)

    SciTech Connect (OSTI)

    Koontz, AS; Choudhury, S; Ermold, BD: Gaustad, KL

    2007-11-01

    The purpose of this report is to provide status of the ingest software used to process instrument data for the Atmospheric Radiation Measurement Program Climate Research Facility (ACRF). The report is divided into 4 sections: (1) for news about ingests currently under development, (2) for current production ingests, (3) for future ingest development plans, and (4) for information on retired ingests. Please note that datastreams beginning in “xxx” indicate cases where ingests run at multiple ACRF sites, which results in a datastream(s) for each location.

  19. ARM - Field Campaign - AMIE (ACRF MJO Investigation Experiment):

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

    Observations of the Madden Julian Oscillation for Modeling Studies govCampaignsAMIE (ACRF MJO Investigation Experiment): Observations of the Madden Julian Oscillation for Modeling Studies Campaign Links AMIE Website ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : AMIE (ACRF MJO Investigation Experiment): Observations of the Madden Julian Oscillation for Modeling Studies 2011.10.01 - 2012.03.31 Website

  20. ACRF Instrumentation Status: New, Current, and Future - October November 2007

    SciTech Connect (OSTI)

    JW Voyles

    2007-11-30

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) instrumentation status. The report is divided into the following four sections: (1) new instrumentation in the process of being acquired and deployed, (2) existing instrumentation and progress on improvements or upgrades, (3) proposed future instrumentation, and (4) SBIR instrument development.

  1. ACRF Instrumentation Status: New, Current, and Future - September October 2007

    SciTech Connect (OSTI)

    JW Voyles

    2007-10-30

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) instrumentation status. The report is divided into the following four sections: (1) new instrumentation in the process of being acquired and deployed, (2) existing instrumentation and progress on improvements or upgrades, (3) proposed future instrumentation, and (4) SBIR instrument development.

  2. Radiative Closure Studies at the NSA ACRF Site

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

    Radiative Closure Studies at the NSA ACRF Site Delamere, Jennifer Atmospheric and Environmental Research, Inc. Mlawer, Eli Atmospheric & Environmental Research, Inc. Turner, David University of Wisconsin-Madison Clough, Shepard Atmospheric and Environmental Research Jensen, Michael Brookhaven National Laboratory Miller, Mark Brookhaven National Laboratory Johnson, Karen Brookhaven National Laboratory Troyan, David Brookhaven National Laboratory Shippert, Timothy Pacific Northwest National

  3. ACRF Instrumentation Status: New, Current, and Future July 2007

    SciTech Connect (OSTI)

    JC Liljegren

    2007-07-01

    The purpose of this report is to provide a concise but comprehensive overview of ACRF instrumentation status. The report is divided into four sections: (1) new instrumentation in the process of being acquired and deployed, (2) existing instrumentation and progress on improvements or upgrades, (3) proposed future instrumentation, and (4) SBIR instrument development.

  4. Absolute Cavity Pyrgeometer to Measure the Absolute Outdoor Longwave Irradiance with Traceability to International System of Units, SI

    SciTech Connect (OSTI)

    Reda, I.; Zeng, J.; Scheuch, J.; Hanssen, L.; Wilthan, B.; Myers, D.; Stoffel, T.

    2012-03-01

    This article describes a method of measuring the absolute outdoor longwave irradiance using an absolute cavity pyrgeometer (ACP), U.S. Patent application no. 13/049, 275. The ACP consists of domeless thermopile pyrgeometer, gold-plated concentrator, temperature controller, and data acquisition. The dome was removed from the pyrgeometer to remove errors associated with dome transmittance and the dome correction factor. To avoid thermal convection and wind effect errors resulting from using a domeless thermopile, the gold-plated concentrator was placed above the thermopile. The concentrator is a dual compound parabolic concentrator (CPC) with 180{sup o} view angle to measure the outdoor incoming longwave irradiance from the atmosphere. The incoming irradiance is reflected from the specular gold surface of the CPC and concentrated on the 11 mm diameter of the pyrgeometer's blackened thermopile. The CPC's interior surface design and the resulting cavitation result in a throughput value that was characterized by the National Institute of Standards and Technology. The ACP was installed horizontally outdoor on an aluminum plate connected to the temperature controller to control the pyrgeometer's case temperature. The responsivity of the pyrgeometer's thermopile detector was determined by lowering the case temperature and calculating the rate of change of the thermopile output voltage versus the changing net irradiance. The responsivity is then used to calculate the absolute atmospheric longwave irradiance with an uncertainty estimate (U{sub 95}) of {+-}3.96 W m{sup 02} with traceability to the International System of Units, SI. The measured irradiance was compared with the irradiance measured by two pyrgeometers calibrated by the World Radiation Center with traceability to the Interim World Infrared Standard Group, WISG. A total of 408 readings were collected over three different nights. The calculated irradiance measured by the ACP was 1.5 W/m{sup 2} lower than that

  5. Finite Cloud Effects at the ACRF TWP Site Patrick Taylor and...

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

    Patrick Taylor and Robert G. Ellingson Dept. of Meteorology, Florida State University, Tallahassee, FL 32306 Data: Observations are taken at the ACRF TWP Site from June 1999 ...

  6. Use of Long Time-series ACRF Measurements to Improve Data Quality...

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

    1 Use of Long Time-Series ACRF Measurements to Improve Data Quality Analysis Sean Moore Mission Research and Technical Services Santa Barbara, CA ARM Data Quality Office...

  7. Scientific Guidance, Research, and Educational Outreach for the ARM Climate Research Facility (ACRF) in the Southern Great Plains

    SciTech Connect (OSTI)

    Lamb, Peter J.

    2013-06-13

    Scientific Guidance, Research, and Educational Outreach for the ARM Climate Research Facility (ACRF) in the Southern Great Plains

  8. Results of Second Outdoor Comparison Between Absolute Cavity Pyrgeometer (ACP) and Infrared Integrating Sphere (IRIS) Radiometer at PMOD (Presentation)

    SciTech Connect (OSTI)

    Reda, I.; Grobner, J.; Wacker, S.

    2014-01-01

    The Absolute Cavity Pyrgeometer (ACP) and InfraRed Integrating Sphere radiometer (IRIS) are developed to establish a world reference for calibrating pyrgeometers with traceability to SI units. The two radiometers are un-windowed with negligible spectral dependence, and traceable to SI units through the temperature scale (ITS-90). The second outdoor comparison between the two designs was held from September 30 to October 11, 2013 at the Physikalisch-Metorologisches Observatorium Davos (PMOD). The difference between the irradiance measured by ACP and that of the IRIS was within 1 W/m2 (3 IRISs: PMOD + Australia + Germany). From the first and second comparisons, a difference of 4-6 W/m2 was observed between the irradiance measured by ACP&IRIS and that of the interim World Infrared Standard Group (WISG). This presentation includes results from the first and second comparison in an effort to establish the world reference for pyrgeometer calibrations, a key deliverable for the World Meteorological Organization (WMO), and the DOE-ASR.

  9. George Smoot, Blackbody, and Anisotropy of the Cosmic Microwave...

    Office of Scientific and Technical Information (OSTI)

    George Smoot, Blackbody, and Anisotropy of the Cosmic Microwave Background Radiation ... of the cosmic microwave background radiation." '1 Smoot previously won the Ernest ...

  10. DOE/SC-ARM/P-07-002.3 ACRF Instrumentation Status: New, Current, and Future

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

    3 ACRF Instrumentation Status: New, Current, and Future March 2007 James Liljegren ACRF Instrument Team Coordinator Work supported by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research Summary The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Program Climate Research Facility instrumentation status. The report is divided into four sections: (1) new instrumentation in the process of

  11. Results of First Outdoor Comparison Between Absolute Cavity Pyrgeometer (ACP) and Infrared Integrating Sphere (IRIS) Radiometer at PMOD (Presentation)

    SciTech Connect (OSTI)

    Reda, I.; Grobner, J.; Wacker, S.; Stoffel, T.

    2013-03-01

    The ACP and IRIS are developed to establish a world reference for calibrating pyrgeometers with traceability to SI units. The two radiometers are unwindowed with negligible spectral dependence, and traceable to SI units through the temperature scale (ITS-90). The first outdoor comparison between the two designs was held from January 28 to February 8, 2013 at the Physikalisch-Metorologisches Observatorium Davos (PMOD). The difference between the irradiance measured by ACP and that of IRIS was within 1 W/m2. A difference of 5 W/m2 was observed between the irradiance measured by ACP&IRIS and that of the interim World Infrared Standard Group (WISG).

  12. Measurements of Martin-Puplett Interferometer Limitations using Blackbody

    Office of Scientific and Technical Information (OSTI)

    Source (Conference) | SciTech Connect Conference: Measurements of Martin-Puplett Interferometer Limitations using Blackbody Source Citation Details In-Document Search Title: Measurements of Martin-Puplett Interferometer Limitations using Blackbody Source Frequency domain measurements with Martin-Puplett interferometer is one of a few techniques capable of bunch length measurements at the level of ~ 100 fs. As the bunch length becomes shorter, it is important to know and be able to measure

  13. Atmospheric Radiation Measurement Climate Research Facility (ACRF) Annual Report 2008

    SciTech Connect (OSTI)

    LR Roeder

    2008-12-01

    The Importance of Clouds and Radiation for Climate Change: The Earth’s surface temperature is determined by the balance between incoming solar radiation and thermal (or infrared) radiation emitted by the Earth back to space. Changes in atmospheric composition, including greenhouse gases, clouds, and aerosols, can alter this balance and produce significant climate change. Global climate models (GCMs) are the primary tool for quantifying future climate change; however, there remain significant uncertainties in the GCM treatment of clouds, aerosol, and their effects on the Earth’s energy balance. In 1989, the U.S. Department of Energy (DOE) Office of Science created the Atmospheric Radiation Measurement (ARM) Program to address scientific uncertainties related to global climate change, with a specific focus on the crucial role of clouds and their influence on the transfer of radiation in the atmosphere. To reduce these scientific uncertainties, the ARM Program uses a unique twopronged approach: • The ARM Climate Research Facility, a scientific user facility for obtaining long-term measurements of radiative fluxes, cloud and aerosol properties, and related atmospheric characteristics in diverse climate regimes; and • The ARM Science Program, focused on the analysis of ACRF and other data to address climate science issues associated with clouds, aerosols, and radiation, and to improve GCMs. This report provides an overview of each of these components and a sample of achievements for each in fiscal year (FY) 2008.

  14. Design, manufacture, and calibration of infrared radiometric blackbody sources

    SciTech Connect (OSTI)

    Byrd, D.A.; Michaud, F.D.; Bender, S.C.

    1996-04-01

    A Radiometric Calibration Station (RCS) is being assembled at the Los Alamos National Laboratories (LANL) which will allow for calibration of sensors with detector arrays having spectral capability from about 0.4-15 {mu}m. The configuration of the LANL RCS. Two blackbody sources have been designed to cover the spectral range from about 3-15 {mu}m, operating at temperatures ranging from about 180-350 K within a vacuum environment. The sources are designed to present a uniform spectral radiance over a large area to the sensor unit under test. The thermal uniformity requirement of the blackbody cavities has been one of the key factors of the design, requiring less than 50 mK variation over the entire blackbody surface to attain effective emissivity values of about 0.999. Once the two units are built and verified to the level of about 100 mK at LANL, they will be sent to the National Institute of Standards and Technology (NIST), where at least a factor of two improvement will be calibrated into the blackbody control system. The physical size of these assemblies will require modifications of the existing NIST Low Background Infrared (LBIR) Facility. LANL has constructed a bolt-on addition to the LBIR facility that will allow calibration of our large aperture sources. Methodology for attaining the two blackbody sources at calibrated levels of performance equivalent to present state of the art will be explained in the following.

  15. DOE/SC-ARM/P-07-002.7 ACRF Instrumentation Status: New, Current...

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

    ......... 16 2.30.1 Develop Dynamic Rain Gauge Calibration Facility ... At blackbody temperatures less than -20C, the Dow Corning 200 fluid viscosity increases, ...

  16. Initial Evaluation of the Cumulus Potential Scheme at the ACRF SGP Site

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

    Meeting, 12 March 2008 Initial Evaluation of the Cumulus Potential Scheme at the ACRF SGP Site Larry K. Berg, William I. Gustafson Jr., and Evgueni I. Kassianov Pacific Northwest National Laboratory ARM Science Team Meeting, 12 March 2008 Where are We Going? Development Simulation Evaluation Observations ARM Science Team Meeting, 12 March 2008 Development: Coupling Clouds to the Convective Boundary Layer * Shallow cumuli are turbulently coupled to the planetary boundary layer 4 3 2 1 0 Height

  17. Quantum driven dissipative parametric oscillator in a blackbody radiation field

    SciTech Connect (OSTI)

    Pachn, Leonardo A.; Department of Chemistry and Center for Quantum Information and Quantum Control, Chemical Physics Theory Group, University of Toronto, Toronto, Ontario M5S 3H6 ; Brumer, Paul

    2014-01-15

    We consider the general open system problem of a charged quantum oscillator confined in a harmonic trap, whose frequency can be arbitrarily modulated in time, that interacts with both an incoherent quantized (blackbody) radiation field and with an arbitrary coherent laser field. We assume that the oscillator is initially in thermodynamic equilibrium with its environment, a non-factorized initial density matrix of the system and the environment, and that at t = 0 the modulation of the frequency, the coupling to the incoherent and the coherent radiation are switched on. The subsequent dynamics, induced by the presence of the blackbody radiation, the laser field, and the frequency modulation, is studied in the framework of the influence functional approach. This approach allows incorporating, in analytic closed formulae, the non-Markovian character of the oscillator-environment interaction at any temperature as well the non-Markovian character of the blackbody radiation and its zero-point fluctuations. Expressions for the time evolution of the covariance matrix elements of the quantum fluctuations and the reduced density-operator are obtained.

  18. Magnetic blackbody shift of hyperfine transitions for atomic clocks

    SciTech Connect (OSTI)

    Berengut, J. C.; Flambaum, V. V.; King-Lacroix, J.

    2009-12-15

    We derive an expression for the magnetic blackbody shift of hyperfine transitions such as the cesium primary reference transition which defines the second. The shift is found to be a complicated function of temperature, and has a T{sup 2} dependence only in the high-temperature limit. We also calculate the shift of ground-state p{sub 1/2} hyperfine transitions which have been proposed as new atomic clock transitions. In this case interaction with the p{sub 3/2} fine-structure multiplet may be the dominant effect.

  19. Measurements of Martin-Puplett Interferometer Limitations using Blackbody Source

    SciTech Connect (OSTI)

    Evtushenko, Pavel E.; Klopf, John M.

    2013-06-01

    Frequency domain measurements with Martin-Puplett interferometer is one of a few techniques capable of bunch length measurements at the level of ~ 100 fs. As the bunch length becomes shorter, it is important to know and be able to measure the limitations of the instrument in terms of shortest measurable bunch length. In this paper we describe an experiment using a blackbody source with the modified Martin-Puplett interferometer that is routine- ly used for bunch length measurements at the JLab FEL, as a way to estimate the shortest, measurable bunch length. The limitation comes from high frequency cut-off of the wire-grid polarizer currently used and is estimated to be 50 fs RMS. The measurements are made with the same Golay cell detector that is used for beam measure- ments. We demonstrate that, even though the blackbody source is many orders of magnitude less bright than the coherent transition or synchrotron radiation, it can be used for the measurements and gives a very good signal to noise ratio in combination with lock-in detection. We also compare the measurements made in air and in vacuum to characterize the very strong effect of the atmospheric absorption.

  20. Blackbody material

    SciTech Connect (OSTI)

    Lauf, Robert J.; Hamby, Jr., Clyde; Akerman, M. Alfred; Trivelpiece, Alvin W.

    1994-01-01

    A light emitting article comprises a composite of carbon-bonded carbon fibers, prepared by: blending carbon fibers with a carbonizable organic powder to form a mixture; dispersing the mixture into an aqueous slurry; vacuum molding the aqueous slurry to form a green article; drying and curing the green article to form a cured article; and, carbonizing the cured article at a temperature of at least about 1000.degree. C. to form a carbon-bonded carbon fiber light emitting composite article having a bulk density less than 1 g/cm.sup.3.

  1. Frequency Shift of the Cesium Clock Transition due to Blackbody Radiation

    SciTech Connect (OSTI)

    Angstmann, E. J.; Dzuba, V. A.; Flambaum, V. V.

    2006-07-28

    We perform ab initio calculations of the frequency shift induced by a static electric field on the cesium clock hyperfine transition. The calculations are used to find the frequency shifts due to blackbody radiation. Our result [{delta}{nu}/E{sup 2}=-2.26(2)x10{sup -10} Hz/(V/m){sup 2}] is in good agreement with early measurements and ab initio calculations performed in other groups. We present arguments against recent claims that the actual value of the effect might be smaller. The difference ({approx}10%) between ab initio and semiempirical calculations is due to the contribution of the continuum spectrum in the sum over intermediate states.

  2. The Status of the ACRF Millimeter Wave Cloud Radars (MMCRs), the Path Forward for Future MMCR Upgrades, the Concept of 3D Volume Imaging Radar and the UAV Radar

    SciTech Connect (OSTI)

    P Kollias; MA Miller; KB Widener; RT Marchand; TP Ackerman

    2005-12-30

    The United States (U.S.) Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) operates millimeter wavelength cloud radars (MMCRs) in several climatological regimes. The MMCRs, are the primary observing tool for quantifying the properties of nearly all radiatively important clouds over the ACRF sites. The first MMCR was installed at the ACRF Southern Great Plains (SGP) site nine years ago and its original design can be traced to the early 90s. Since then, several MMCRs have been deployed at the ACRF sites, while no significant hardware upgrades have been performed. Recently, a two-stage upgrade (first C-40 Digital Signal Processors [DSP]-based, and later the PC-Integrated Radar AcQuisition System [PIRAQ-III] digital receiver) of the MMCR signal-processing units was completed. Our future MMCR related goals are: 1) to have a cloud radar system that continues to have high reliability and uptime and 2) to suggest potential improvements that will address increased sensitivity needs, superior sampling and low cost maintenance of the MMCRs. The Traveling Wave Tube (TWT) technology, the frequency (35-GHz), the radio frequency (RF) layout, antenna, the calibration and radar control procedure and the environmental enclosure of the MMCR remain assets for our ability to detect the profile of hydrometeors at all heights in the troposphere at the ACRF sites.

  3. Radiometric characterization of a high temperature blackbody in the visible and near infrared

    SciTech Connect (OSTI)

    Taubert, R. D.; Hollandt, J.

    2013-09-11

    At the Physikalisch-Technische Bundesanstalt the radiance temperature in the range from 962 C to 3000 C is disseminated by applying a high temperature blackbody (HTBB) with a directly heated pyrolytic graphite cavity. The thermodynamic radiance temperature of the HTBB was measured in the temperature range from 1000 C to 3000 C by applying almost simultaneously absolutely calibrated silicon photodiode based filter radiometers with centre wavelengths at 476 nm, 676 nm, 800 nm, 900 nm and 1000 nm and InGaAs photodiode based filter radiometers with centre wavelengths at 1300 nm, 1550 nm and 1595 nm. The results demonstrate that, expressed in terms of irradiance, within an uncertainty of 0.1 % (k=1) in a broad wavelength range the thermodynamic radiance temperature of the HTBB is wavelength independent in the investigated temperature interval.

  4. ARM - Publications: Science Team Meeting Documents

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

    Pyrgeometer Calibrations at NREL Reda, I. and Stoffel, T., National Renewable Energy Laboratory Eleventh Atmospheric Radiation Measurement (ARM) Science Team Meeting The ARM Program has acquired a new Pyrgeometer Blackbody Calibration System to improve the data quality of longwave measurements from the SIRS, GNDRAD, and SKYRAD instrument platforms. Results of the acceptance tests and subsequent indoor and outdoor pyrgeometer calibrations at NREL's Solar Radiation Research Laboratory are

  5. Slide 1

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

    in the Blackbody Calibration of Pyrgeometers By Ibrahim Reda, Julian Gröbner * , Tom Stoffel, Daryl Myers, and Bruce Forgan ** Eighteenth Atmospheric Radiation Measurement (ARM) Program Science Team Meeting *Physikalisch-Meteorologisches Observatorium Davos, World Radiation Center (PMOD/WRC) ** Bureau of Meteorology, Australia Abstract Pyrgeometers are used to measure the atmospheric longwave irradiance through out the ARM program sites. Previous calibrations of pyrgeometers using

  6. ACRF-Newsletter.indd

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

    For centuries, observations of atmospheric temperature, pressure, humidity and winds were limited primarily by where instruments could be located. More recently, remote instrument platforms such as radars and satellites have been deployed to explore portions of the atmosphere beyond the reach of conventional weather instruments. With the objective of studying radiation transfer in the atmosphere as a whole, the ARM by Dr. Kevin Kloesel, University of Oklahoma Program seeks to measure atmospheric

  7. ARM - Field Campaign - International Pyrgeometer Intercomparison

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

    Twenty-one instruments of four different types from 10countries participated, including Switzerland, Germany, Japan, Israel, Nigeria, Australia, Canada, Saudi Arabia, Holland and ...

  8. reda(1)-99.PDF

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

    Pyrgeometer Calibrations for the ARM Program I. Reda, T. L. Stoffel, and J. A. Treadwell National Renewable Energy Laboratory Golden, Colorado J. Hickey The Eppley Laboratory, Inc. Newport, Rhode Island Introduction Pyrgeometers are used to measure the longwave radiation. Accurate measurements from these radiometers require regular calibration using temperature controlled blackbody radiators. The National Renewable Energy Laboratory (NREL) and The Eppley Laboratory, Inc. (EPLAB) are developing a

  9. Aether Drift and the isotropy of the universe: a measurement of anisotropes in the primordial black-body radiation. Final report, 1 November 1978-31 October 1980

    SciTech Connect (OSTI)

    Smoot, G.F.

    1981-07-01

    Large-angular-scale anisotropies in the 3 K primordial black-body radiation were detected and mapped with a sensitivity of 2 x to the minus 4 power K and an angular resolution of about 10 deg. The motion of the Earth with respect to the distant matter of the Universe ( Aether Drift ) was measured and the homogeneity and isotropy of the Universe (the Cosmological Principle ) was probed. The experiment uses two Dicke radiometers, one at 33 GHz to detect the cosmic anisotropy, and one at 54 GHz to detect anisotropies in the residual oxygen above the detectors. The system was installed in the NASA-Ames Earth survey aircraft (U-2), and operated successfully in a series of flights in both the Northern and Southern Hemispheres. Data taking and analysis to measure the anisotropy were successful.

  10. Traceable Pyrgeometer Calibrations (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Sponsoring Org: USDOE Office of Energy Efficiency and Renewable Energy (EERE) Country of Publication: United States Language: English Subject: 14 SOLAR ENERGY Atmospheric Radiation ...

  11. Traceable Pyrgeometer Calibrations (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Sponsoring Org: USDOE Office of Energy Efficiency and Renewable Energy (EERE) Country of Publication: United States Language: English Subject: 14 SOLAR ENERGY Broadband Outdoor ...

  12. Traceable Pyrgeometer Calibrations (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Research Org: NREL (National Renewable Energy Laboratory (NREL), Golden, CO (United States)) Sponsoring Org: USDOE Office of Energy Efficiency and Renewable Energy (EERE) Country ...

  13. ARM - Datastreams - prprad

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

    pyrgeometer degC downlonghemispcasetemp ( time ) Downwelling pyrgeometer dome thermistor temperature, pyrgeometer degC downlonghemispdometemp ( time ) Standard...

  14. ACRF Data Collection and Processing Infrastructure

    SciTech Connect (OSTI)

    Macduff, M; Egan, D

    2004-12-01

    We present a description of the data flow from measurement to long-term archive. We also discuss data communications infrastructure. The data handling processes presented include collection, transfer, ingest, quality control, creation of Value-Added Products (VAP), and data archiving.

  15. ACRF Instrumentation Status and Information - June 2009

    SciTech Connect (OSTI)

    JW Voyles

    2009-06-01

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following five sections: (1) new instrumentation in the process of being acquired and deployed, (2) field campaigns, (3) existing instrumentation and progress on improvements or upgrades, (4) proposed future instrumentation, and (5) Small Business Innovation Research instrument development.

  16. ACRF Instrumentation Status and Information September 2009

    SciTech Connect (OSTI)

    JW Voyles

    2009-10-01

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following five sections: (1) new instrumentation in the process of being acquired and deployed, (2) field campaigns, (3) existing instrumentation and progress on improvements or upgrades, (4) proposed future instrumentation, and (5) Small Business Innovation Research instrument development.

  17. ACRF Instrumentation Status and Information April 2009

    SciTech Connect (OSTI)

    Voyles, JW

    2009-05-07

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following five sections: (1) new instrumentation in the process of being acquired and deployed, (2) field campaigns, (3) existing instrumentation and progress on improvements or upgrades, (4) proposed future instrumentation, and (5) Small Business Innovation Research instrument development.

  18. ACRF Instrumentation Status and Information July 2009

    SciTech Connect (OSTI)

    JW Voyles

    2009-08-13

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following five sections: (1) new instrumentation in the process of being acquired and deployed, (2) field campaigns, (3) existing instrumentation and progress on improvements or upgrades, (4) proposed future instrumentation, and (5) Small Business Innovation Research instrument development.

  19. ACRF Instrumentation Status and Information May 2009

    SciTech Connect (OSTI)

    JW Voyles

    2009-05-01

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following five sections: (1) new instrumentation in the process of being acquired and deployed, (2) field campaigns, (3) existing instrumentation and progress on improvements or upgrades, (4) proposed future instrumentation, and (5) Small Business Innovation Research instrument development.

  20. ACRF Instrumentation Status and Information August 2009

    SciTech Connect (OSTI)

    JW Voyles

    2009-09-09

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following five sections: (1) new instrumentation in the process of being acquired and deployed, (2) field campaigns, (3) existing instrumentation and progress on improvements or upgrades, (4) proposed future instrumentation, and (5) Small Business Innovation Research instrument development.

  1. ACRF Data Collection and Processing Infrastructure

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

    ... This, in turn, reduces downtime and instrument outages. Centralizing the monitoring ... 2004, ARM TR-046 engineering design, review, and testing will have long-term dividends. ...

  2. Near-Blackbody Enclosed Particle Receiver

    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.

  3. Direct Thermal Receivers Using Near Blackbody Configurations...

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

    high cost, and limited thermal conversion efficiency. To achieve the Department of Energy SunShot goal of high efficiency, low cost renewable power generation, a highly efficient ...

  4. ACRF Instrumentation Status: New, Current, and Future - June 2008

    SciTech Connect (OSTI)

    JW Voyles

    2008-07-01

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following five sections: (1) new instrumentation in the process of being acquired and deployed, (2) field campaigns, (3) existing instrumentation and progress on improvements or upgrades, (4) proposed future instrumentation, and (5) Small Business Innovation Research instrument development.

  5. ACRF Instrumentation Status: New, Current, and Future - August 2008

    SciTech Connect (OSTI)

    JW Voyles

    2008-09-01

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following five sections: (1) new instrumentation in the process of being acquired and deployed, (2) field campaigns, (3) existing instrumentation and progress on improvements or upgrades, (4) proposed future instrumentation, and (5) Small Business Innovation Research instrument development.

  6. ACRF Instrumentation Status: New, Current, and Future - November December 2007

    SciTech Connect (OSTI)

    JW Voyles

    2007-12-01

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following four sections: (1) new instrumentation in the process of being acquired and deployed, (2) existing instrumentation and progress on improvements or upgrades, (3) proposed future instrumentation, and (4) Small Business Innovation Research instrument development.

  7. ACRF Instrumentation Status: New, Current, and Future - July 2008

    SciTech Connect (OSTI)

    JW Voyles

    2008-07-01

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following five sections: (1) new instrumentation in the process of being acquired and deployed, (2) field campaigns, (3) existing instrumentation and progress on improvements or upgrades, (4) proposed future instrumentation, and (5) Small Business Innovation Research instrument development.

  8. ACRF Instrumentation Status: New, Current, and Future - April 2008

    SciTech Connect (OSTI)

    JW Voyles

    2008-05-01

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following five sections: (1) new instrumentation in the process of being acquired and deployed, (2) field campaigns, (3) existing instrumentation and progress on improvements or upgrades, (4) proposed future instrumentation, and (5) Small Business Innovation Research instrument development.

  9. ACRF Instrumentation Status: New, Current, and Future - December 2008

    SciTech Connect (OSTI)

    JW Voyles

    2009-01-15

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following five sections: (1) new instrumentation in the process of being acquired and deployed, (2) field campaigns, (3) existing instrumentation and progress on improvements or upgrades, (4) proposed future instrumentation, and (5) Small Business Innovation Research instrument development.

  10. ACRF Instrumentation Status: New, Current, and Future - March 2008

    SciTech Connect (OSTI)

    JW Voyles

    2008-04-01

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following four sections: (1) new instrumentation in the process of being acquired and deployed, (2) existing instrumentation and progress on improvements or upgrades, (3) proposed future instrumentation, and (4) Small Business Innovation Research instrument development.

  11. ACRF Instrumentation Status: New, Current, and Future - October 2008

    SciTech Connect (OSTI)

    JW Voyles

    2008-10-01

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following five sections: (1) new instrumentation in the process of being acquired and deployed, (2) field campaigns, (3) existing instrumentation and progress on improvements or upgrades, (4) proposed future instrumentation, and (5) Small Business Innovation Research instrument development.

  12. ACRF Instrumentation Status: New, Current, and Future - May 2008

    SciTech Connect (OSTI)

    JW Voyles

    2008-05-01

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following five sections: (1) new instrumentation in the process of being acquired and deployed, (2) field campaigns, (3) existing instrumentation and progress on improvements or upgrades, (4) proposed future instrumentation, and (5) Small Business Innovation Research instrument development.

  13. ACRF Instrumentation Status: New, Current, and Future - November 2008

    SciTech Connect (OSTI)

    JW Voyles

    2008-12-01

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following five sections: (1) new instrumentation in the process of being acquired and deployed, (2) field campaigns, (3) existing instrumentation and progress on improvements or upgrades, (4) proposed future instrumentation, and (5) Small Business Innovation Research instrument development.

  14. ACRF Instrumentation Status: New, Current, and Future - September 2008

    SciTech Connect (OSTI)

    JW Voyles

    2008-10-15

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following five sections: (1) new instrumentation in the process of being acquired and deployed, (2) field campaigns, (3) existing instrumentation and progress on improvements or upgrades, (4) proposed future instrumentation, and (5) Small Business Innovation Research instrument development.

  15. ACRF Instrumentation Status: New, Current, and Future - February 2008

    SciTech Connect (OSTI)

    JW Voyles

    2008-03-01

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following four sections: (1) new instrumentation in the process of being acquired and deployed, (2) existing instrumentation and progress on improvements or upgrades, (3) proposed future instrumentation, and (4) Small Business Innovation Research instrument development.

  16. ACRF Instrumentation Status: New, Current, and Future February 2009

    SciTech Connect (OSTI)

    JW Voyles

    2009-02-15

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following five sections: (1) new instrumentation in the process of being acquired and deployed, (2) field campaigns, (3) existing instrumentation and progress on improvements or upgrades, (4) proposed future instrumentation, and (5) Small Business Innovation Research instrument development.

  17. Interannual variation of cloud optical properties at ACRF Manus...

    Office of Scientific and Technical Information (OSTI)

    Additional Journal Information: Journal Volume: 153; Journal Issue: C; Journal ID: ISSN 0022-4073 Publisher: Elsevier Sponsoring Org: USDOE Office of Science (SC), Biological and ...

  18. ACRF Instrumentation Status: New, Current, and Future January 2007

    SciTech Connect (OSTI)

    JC Liljegren

    2007-01-01

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Program Climate Research Facility instrumentation status. The report is divided into four sections: (1) new instrumentation in the process of being acquired and deployed, (2) existing instrumentation and progress on improvements or upgrades, (3) proposed future instrumentation, and (4) Small Business Innovation Research instrument development.

  19. ACRF Instrumentation Status: New, Current, and Future September 2006

    SciTech Connect (OSTI)

    JC Liljegren

    2006-09-01

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Program Climate Research Facility instrumentation status. The report is divided into four sections: (1) new instrumentation in the process of being acquired and deployed, (2) existing instrumentation and progress on improvements or upgrades, (3) proposed future instrumentation, and (4) Small Business Innovation Research instrument development. New information is highlighted in blue text.

  20. ACRF Instrumentation Status: New, Current, and Future October 2006

    SciTech Connect (OSTI)

    JC Liljegren

    2006-10-01

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Program Climate Research Facility instrumentation status. The report is divided into four sections: (1) new instrumentation in the process of being acquired and deployed, (2) existing instrumentation and progress on improvements or upgrades, (3) proposed future instrumentation, and (4) Small Business Innovation Research instrument development.

  1. ACRF Instrumentation Status: New, Current, and Future February 2007

    SciTech Connect (OSTI)

    JC Liljegren

    2007-02-01

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Program Climate Research Facility instrumentation status. The report is divided into four sections: (1) new instrumentation in the process of being acquired and deployed, (2) existing instrumentation and progress on improvements or upgrades, (3) proposed future instrumentation, and (4) Small Business Innovation Research instrument development

  2. ACRF Instrumentation Status: New, Current, and Future August 2006

    SciTech Connect (OSTI)

    JC Liljegren

    2006-08-01

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Program Climate Research Facility instrumentation status. The report is divided into four sections: (1) new instrumentation in the process of being acquired and deployed, (2) existing instrumentation and progress on improvements or upgrades, (3) proposed future instrumentation, and (4) Small Business Innovation Research instrument development. New information is highlighted in blue text.

  3. ACRF Instrumentation Status: New, Current, and Future May 2007

    SciTech Connect (OSTI)

    JC Liljegren

    2007-05-01

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Program Climate Research Facility instrumentation status. The report is divided into four sections: (1) new instrumentation in the process of being acquired and deployed, (2) existing instrumentation and progress on improvements or upgrades, (3) proposed future instrumentation, and (4) Small Business Innovation Research instrument development.

  4. ACRF Instrumentation Status: New, Current, and Future June 2007

    SciTech Connect (OSTI)

    JC Liljegren

    2007-06-01

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Program Climate Research Facility instrumentation status. The report is divided into four sections: (1) new instrumentation in the process of being acquired and deployed, (2) existing instrumentation and progress on improvements or upgrades, (3) proposed future instrumentation, and (4) Small Business Innovation Research instrument development.

  5. ACRF Instrumentation Status: New, Current, and Future May 2007

    SciTech Connect (OSTI)

    JC Liljegren

    2007-04-01

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Program Climate Research Facility instrumentation status. The report is divided into four sections: (1) new instrumentation in the process of being acquired and deployed, (2) existing instrumentation and progress on improvements or upgrades, (3) proposed future instrumentation, and (4) Small Business Innovation Research instrument development.

  6. ACRF Instrumentation Status: New, Current, and Future - January 2009

    SciTech Connect (OSTI)

    JW Voyles

    2009-03-02

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following five sections: (1) new instrumentation in the process of being acquired and deployed, (2) field campaigns, (3) existing instrumentation and progress on improvements or upgrades, (4) proposed future instrumentation, and (5) Small Business Innovation Research instrument development.

  7. ACRF Instrumentation Status: New, Current, and Future July 2006

    SciTech Connect (OSTI)

    JC Liljegren

    2006-07-01

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Program Climate Research Facility instrumentation status. The report is divided into four sections: (1) new instrumentation in the process of being acquired and deployed, (2) existing instrumentation and progress on improvements or upgrades, (3) proposed future instrumentation, and (4) Small Business Innovation Research instrument development. New information is highlighted in blue text.

  8. ACRF Instrumentation Status: New, Current, and Future March 2007

    SciTech Connect (OSTI)

    JC Liljegren

    2007-03-01

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Program Climate Research Facility instrumentation status. The report is divided into four sections: (1) new instrumentation in the process of being acquired and deployed, (2) existing instrumentation and progress on improvements or upgrades, (3) proposed future instrumentation, and (4) Small Business Innovation Research instrument development.

  9. ACRF Instrumentation Status: New, Current, and Future March 2009

    SciTech Connect (OSTI)

    JW Voyles

    2009-03-15

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following five sections: (1) new instrumentation in the process of being acquired and deployed, (2) field campaigns, (3) existing instrumentation and progress on improvements or upgrades, (4) proposed future instrumentation, and (5) Small Business Innovation Research instrument development.

  10. George Smoot, Blackbody, and Anisotropy of the Cosmic Microwave...

    Office of Scientific and Technical Information (OSTI)

    He shares the award with John C. Mather of NASA Goddard Space Flight Center. The citation ... In addition, one of the principal instruments for the NASA COBE experiment used to make ...

  11. Search for: All records | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    ... energy laboratory (1) nrel (1) pv module (1) pyrgeometer (1) pyrgeometers (1) solar energy atmospheric radiation measurement (1) solar energy broadband outdoor radiometer ...

  12. ARM - Datastreams - rad

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

    Resistance Kohms downlonghemispcaseresist ( time ) Downwelling Pyrgeometer Dome Thermistor Resistance kohm downlonghemispdomeresist ( time ) Downwelling Longwave...

  13. Atmospheric Radiation Measurement Climate Research Facility (ACRF Instrumentation Status: New, Current, and Future)

    SciTech Connect (OSTI)

    JW Voyles

    2008-01-30

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following four sections: (1) new instrumentation in the process of being acquired and deployed, (2) existing instrumentation and progress on improvements or upgrades, (3) proposed future instrumentation, and (4) Small Business Innovation Research instrument development.

  14. ORNL, ACRF Archive: Raymond McCord, Giri Palanisamy, Karen Gibson...

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

    McCord, Giri Palanisamy, Karen Gibson, W. Christopher Lenhardt Mission Research: Sean Moore Show me... - Exis'ng Func'onality * Mul'ple interfaces (Data, Catalog, Thumbnail...

  15. Microsoft Word - ACRF4thQuarterFY09 draft_nb__sal.doc

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

    6 Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report July 1 - September 30, 2009 Work supported by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research July 1 - September 30, 2009, DOE/SC-ARM/P-09-016 iii Contents 1. Data Availability ................................................................................................................................... 1 2. Scientific Users

  16. ACRF Instrumentation Status: New, Current, and Future November-December 2006

    SciTech Connect (OSTI)

    JC Liljegren

    2006-12-01

    The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Program Climate Research Facility instrumentation status. The report is divided into four sections: (1) new instrumentation in the process of being acquired and deployed, (2) existing instrumentation and progress on improvements or upgrades, (3) proposed future instrumentation, and (4) Small Business Innovation Research instrument development.

  17. “Lidar Investigations of Aerosol, Cloud, and Boundary Layer Properties Over the ARM ACRF Sites”

    SciTech Connect (OSTI)

    Ferrare, Richard; Turner, David

    2015-01-13

    Project goals; Characterize the aerosol and ice vertical distributions over the ARM NSA site, and in particular to discriminate between elevated aerosol layers and ice clouds in optically thin scattering layers; Characterize the water vapor and aerosol vertical distributions over the ARM Darwin site, how these distributions vary seasonally, and quantify the amount of water vapor and aerosol that is above the boundary layer; Use the high temporal resolution Raman lidar data to examine how aerosol properties vary near clouds; Use the high temporal resolution Raman lidar and Atmospheric Emitted Radiance Interferometer (AERI) data to quantify entrainment in optically thin continental cumulus clouds; and Use the high temporal Raman lidar data to continue to characterize the turbulence within the convective boundary layer and how the turbulence statistics (e.g., variance, skewness) is correlated with larger scale variables predicted by models.

  18. Lidar Investigations of Aerosol, Cloud, and Boundary Layer Properties Over the ARM ACRF Sites

    SciTech Connect (OSTI)

    Turner, David D.; Ferrare, Richard

    2015-01-13

    The systematic and routine measurements of aerosol, water vapor, and clouds in the vertical column above the Atmospheric Radiation Measurement (ARM) sites from surface-based remote sensing systems provides a unique and comprehensive data source that can be used to characterize the boundary layer (i.e., the lowest 3 km of the atmosphere) and its evolution. New algorithms have been developed to provide critical datasets from ARM instruments, and these datasets have been used in long-term analyses to better understand the climatology of water vapor and aerosol over Darwin, the turbulent structure of the boundary layer and its statistical properties over Oklahoma, and to better determine the distribution of ice and aerosol particles over northern Alaska.

  19. Microsoft PowerPoint - poster_08_final.ppt [Compatibility Mode...

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

    Technical Services, Santa Barbara, CA ; , , 3 ACRF d th Okl h M t1 Pl tti T l 3 ACRF and the Oklahoma Mesonet1 Plotting Tools 3. ACRF and the Oklahoma Mesonet 1. Plotting Tools ...

  20. ARM Orientation Workshop

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

    Obtaining Data from the ACRF Archive Orientation for new Science Team Members One click to the ACRF Data Archive ACRF Data Archive - Newly Designed Home Page Emphasis on guiding ...

  1. ARM - Facility News Article

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

    been retired and the updated pages are now located under the "About ACRF" web pages at http:engineering.arm.govengrtaskindex.stm From the ACRF Engineering...

  2. Charge

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

    2. SUMMARY OF ACRF INFRASTRUCTURE REVIEW PANEL COMMENTS...... 3 2.1 ... of Energy Review of the ACRF: Review Panel ......C.1 iii DOE...

  3. Microsoft Word - ISDAC_description.doc

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

    Facility's (ACRF) North Slope of Alaska (NSA) locale for three weeks in April 2008. This ... surface-based measurements at the ACRF NSA locale provide retrievals of aerosol, ...

  4. Southern Great Plains

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

    of DOE's funding for ACRF is to provide educational resources to anyone interested in learning more about climate sciences, weather, research techniques, or instrumentation. ACRF...

  5. Microsoft Word - ACRF3rdQuarterFY09_DOE_SC_ARM_P_09_011.doc

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

    1 Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report April 1 - June 30, 2009 Work supported by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. Neither the United States nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for

  6. Search for: All records | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Filter Results Filter by Subject borcal (1) broadband outdoor radiometer calibrations (1) national renewable energy laboratory (1) nrel (1) pyrgeometer (1) solar energy atmospheric ...

  7. Microsoft PowerPoint - ARM_Stoffel.ppt

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

    calibration? - In Search of a Measurement Reference * References * Acronyms * Appendix - Fundamentals of pyrgeometer operation and calibration 3 Why a Data Access Restriction? ...

  8. Broadband Outdoor Radiometer Callibration Process for the Atmospheric...

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

    ... fleet of solar-related instruments, including pyranometers, pyrgeometers, pyrheliometers, as well as the temperaturerelative humidity probes, multimeters, and data acquisition ...

  9. ARM - Publications: Science Team Meeting Documents: Determination...

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

    of this indirect effect detection is provided by downwelling longwave flux measurements from the NSA pyrgeometers, which show consistently larger fluxes in the high CN...

  10. ARM - Field Campaign - IPASRC II Campaign

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

    calibration improves the accuracy of pyrgeometers compared to a black body calibration. ... Universal Time Coordinates) during the whole IOP. During clear-sky nights, the same ...

  11. ARM - Publications: Science Team Meeting Documents

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

    Effects of Pyrgeometer Dome Heating on Calculated Longwave Radiation Richardson, S.J., University of Oklahoma Eleventh Atmospheric Radiation Measurement (ARM) Science Team Meeting...

  12. Uncertainty Estimates for SIRS, SKYRAD, & GNDRAD Data and Reprocessing...

    Office of Scientific and Technical Information (OSTI)

    Title: Uncertainty Estimates for SIRS, SKYRAD, & GNDRAD Data and Reprocessing the Pyrgeometer Data (Presentation) The National Renewable Energy Laboratory (NREL) and the ...

  13. Microsoft Word - liljegren-jc.doc

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

    Facility (ACRF) North Slope of Alaska (NSA) site at Barrow, Alaska, in February 2004. ... water content (bottom) for March 12-15, 2004, at the ARM ACRF NSA site at Barrow, Alaska. ...

  14. ACTIVITY SPECIFIC FIREARMS SAFETY PLAN FOR

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

    Atmospheric Radiation Measurement Climate Research Facility/ North Slope of Alaska/Adjacent Arctic Ocean (ACRF/NSA/AAO) Activity Specific Firearm Safety Plan for ACRF/North Slope of Alaska Sandia National Laboratories Department 6383, Energy, Climate & Atmospheric Management ACRF/NSA/AAO Revision 14 Activity Specific Firearm Safety Plan for June 2010 ACRF/North Slope of Alaska Signature Page This safety plan is approved by the undersigned and includes the firearm and ammunition storage

  15. ARM - Datastreams - aeri01summary

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

    Measurement Units Variable Ambient blackbody temperature - apex K ABBapexTemp ( time ) ... wnumsum10 ) Hot blackbody temperature - apex K HBBapexTemp ( time ) Hot blackbody ...

  16. ARM Value-Added Product (VAP) Monthly Status Report (March 2007)

    SciTech Connect (OSTI)

    Comstock, J; Flynn, C; Jensen, M; Long, C; Turner, D; Xie, S

    2007-03-01

    The original temporal resolution of the Atmospheric Radiation Measurement (ARM) AERI instruments was 8 minutes, where each cycle consisted of a 3-minute sky-view period and 2-minute views at each of the two blackbody targets. This sampling strategy was chosen to achieve the desired signal-to-noise ratio for clear-sky spectroscopy and profiling studies. To make the AERI observations more useful for cloud research, the temporal resolution has been decreased by an order of magnitude; however, this greatly increases the random error in these observations. This VAP uses a principle component analysis noise filter to significantly reduce the amount of uncorrelated random error in the AERI observations. The noise-filtered 'rapid-sample' AERI observations have approximately the same amount of random error as the original AERI radiance data. The AEROSOL BE VAP provides temporally and spatially continuous vertical profiles of ambient aerosol optical properties including scattering, absorption, and extinction coefficients, single scattering albedo and asymmetry parameter. It uses a combination of passive radiometers, in-situ surface measurements, empirical relationships, climatologies, and model input. It is a direct input to the BBHRP VAP, an ACRF programmatic metric.

  17. ARM - Publications: Science Team Meeting Documents

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

    International Pyrgeometer and Absolute Sky-scanning Radiometer Comparison at the NSA ARM ... conditions will be performed at beginning of March 2001 at ARM NSA site in Barrow, Alaska. ...

  18. ARM - Education Article

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

    7, 2007 [Education] ACRF Education and Outreach Presents Women in Science Conference Bookmark and Share ACRF Education and Outreach staff attemded the Women In Science Conference at the Omniplex Science Museum. ACRF Education and Outreach staff presented information about the Atmospheric Radiation Measurement Program at the Women In Science Conference at the Omniplex Science Museum. The event was sponsored by the Oklahoma Experimental Program to Stimulate Competitive Research (OK-EPSCOR).

  19. ARM - VAP Process - qmelwflux

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

    Productsqmelwflux Documentation & Plots Data Management Facility Plots (Quick Looks) ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send VAP : Comparison of Longwave Flux Data from AERI and LBLRTM vs. pyrgeometer (QMELWFLUX) Instrument Categories Derived Quantities and Models, Radiometric Output Products qmelwflux : QME: longwave Flux, between AERI, LBLRTM, RRTM, and the pyrgeometer Locations Southern Great Plains

  20. Steven K. Krueger, University of Utah

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

    of Cumulus Convection and the Boundary Layer at the Southern Great Plains ACRF Steven K. Krueger, University of Utah from Arakawa and Jung (2003) Interactions of Cumulus...

  1. Recovered File 1

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

    Livermore National Laboratory Dave Turner, Patrick Heck University of ... ACRF - One-year run complete * Shupe-Turner mixed-phase retrieval compared to ...

  2. Search for: All records | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    ... display, and distribution; data stream reprocessing; and engineering and operations management processes and procedures. Future directions in ACRF data quality assurance also ...

  3. Feb09.doc

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

    Donna J. Holdridge Contributor: Lynne Roeder Website: http:www.arm.gov ACRF Southern Great Plains Newsletter is published by Argonne National Laboratory, managed by UChicago...

  4. Nauru Island Effect Detection Data Set (Dataset) | Data Explorer

    Office of Scientific and Technical Information (OSTI)

    Nauru ACRF downwelling SW, wind direction, and air temperature data are used, along with ... fraction; Cloud optical depth; Horizontal wind; Longwave broadband downwelling ...

  5. ARM - Publications: Science Team Meeting Documents: Improved...

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

    Improved Method for Searching ACRF Data Quality and Problem Report Databases Doty, Kathy Brookhaven National Laboratory Wagener, Richard Brookhaven National Laboratory The ...

  6. Slide 1

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

    fiber Original location: 250m SE of Great White Sample data: A Total Precipitation Sensor at the Barrow ACRF Site ABSTRACT A Yankee Environmental TPS-3100 Total Precipitation...

  7. Bench-Scale Cross Flow Filtration of

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

    ... Helpful links to instrument-related ACRF web pages are listed below: Instrument ... Communications latency issues are also under investigation with the RocketPorts and fiber ...

  8. ARM - Education Article

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

    July 8, 2007 Education Climate Research Facility in Papua New Guinea Launches Kiosk Bookmark and Share In 2004, ACRF Education and Outreach worked with Tradewind Communications ...

  9. Newsletter Southern Great Plains

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

    Website: http:www.arm.gov ACRF Southern Great Plains ... Argonne, LLC, for the U.S. Department of Energy ... and their daughters Allison Moore (husband ...

  10. Bench-Scale Cross Flow Filtration of

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

    4 ARM Climate Research Facility Workshop Report November 2008 Work supported by the U.S. ... Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) workshop, held ...

  11. "Lidar Investigations of Aerosol, Cloud, and Boundary Layer Properties...

    Office of Scientific and Technical Information (OSTI)

    Technical Report: "Lidar Investigations of Aerosol, Cloud, and Boundary Layer Properties Over the ARM ACRF Sites" Citation Details In-Document Search Title: "Lidar Investigations ...

  12. Newsletter Southern Great Plains

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

    The ACRF SGP site recently established a repair capability for its wind sensor equipment that is saving the program money and improving the availability of data. Wind sensor ...

  13. ARM - Acronyms

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

    ALFA AER local forecast and assimilation (model) AMF ARM Mobile Facility AMIE ACRF MJO Investigation Experiment AMIP Atmospheric Model Intercomparison Project AMMA African Monsoon ...

  14. Bench-Scale Cross Flow Filtration of

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

    ... The strategy is to replace the current aging MWRs with systems that broaden ACRF's ... the installation of the orthomode transducer at Barrow is on hold while calibration ...

  15. Microsoft Word - lesht.doc

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

    Relative Humidity Climatology at the ARM NSA, SGP, and TWP Climate Research Facility ... ACRF Site Start Date End Date Number of Soundings NSA 04282002 11302003 402 SGP 0501...

  16. ARM - Publications: Science Team Meeting Documents: Establishing...

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

    of Alaska ARM Climate Research Facility (NSA ACRF) are a necessity for both accurate ... of two important initiatives at the NSA site, the Broadband Heating Rate Profile ...

  17. Bench-Scale Cross Flow Filtration of

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

    ... system to the ARM North Slope of Alaska (NSA) locale for a five week Indirect and ... Facility (ACRF) North Slope of Alaska (NSA) locale provide retrievals of aerosol, ...

  18. Nov08.doc

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

    System With more than 300 instrument systems operating at remote sites around the globe, ACRF Instrument Mentors can now use the centralized Operations Support System (OSS)...

  19. Orr 2007 ARM STM poster2.ppt

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

    Responsible for management and maintenance of nearly all data and instrument computers as well as personal computers at the ACRF sites (AMF, NSA, SGP and TWP). Cyber...

  20. What is the ARM Climate Research Facility: Is Global Warming a Real Bias or a Statistical Anomaly?

    SciTech Connect (OSTI)

    Egami, Takeshi; Sisterson, Douglas L.

    2010-03-10

    The Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) is a U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research national user facility. With multi-laboratory management of distributed facilities worldwide, the ACRF does not fit the mold of a traditional user facility located at a national laboratory. The ACRF provides the world's most comprehensive 24/7 observational capabilities for obtaining atmospheric data specifically for climate change research. Serving nearly 5,000 registered users from 15 federal and state agencies, 375 universities, and 67 countries, the ACRF Data Archive collects and delivers over 5 terabytes of data per month to its users. The ACRF users provide critical information about cloud formation processes, water vapor, and aerosols, and their influence on radiative transfer in the atmosphere. This information is used to improve global climate model predictions of climate change.

  1. ARM - Datastreams - aeriengineer

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

    Measurement Units Variable Ambient blackbody temperature - apex K ABBapexTemp ( time ) Decimal representation of percentage weighting of ambient blackbody apex temperature unitless ...

  2. ARM - Datastreams - assistsummary

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

    ... setting degC abbsetpoint ( time ) Ambient blackbody temperature at apex of cavity degC abbthermistorapex ( time ) Ambient blackbody temperature at bottom of cone degC ...

  3. ARM Climate Modeling Best Estimate Lamont, OK (ARMBE-CLDRAD SGPC1)

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

    McCoy, Renata; Xie, Shaocheng

    2012-02-20

    The ARM CMBE-CLDRAD [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected cloud and radiation relevant quantities from ACRF observations

  4. Narrow Field of View Zenith Radiometer (NFOV) Handbook (Technical...

    Office of Scientific and Technical Information (OSTI)

    With a one-second sampling rate of the NFOV2, faster than almost any other ARM Climate Research Facility (ACRF) instrument, we are able, for the first time, to capture changes in ...

  5. ARM - Publications: Science Team Meeting Documents

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

    As part of the conditions of associated funding for ACRF, the ARM Program must attract new users. Located in Darwin, Australia, and the island nations of Papua New Guinea and ...

  6. Newsletter Southern Great Plains

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

    at the ACRF Southern Great Plains (SGP) site has helped to correct problems related to signal interference. The WACR is a 95-GHz system designed for a unique purpose -...

  7. Newsletter Southern Great Plains

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

    6 ANLEVSNL-06-04 Technical Contact: Brad W. Orr Phone: 630-252-8665 Email: brad.orr@anl.gov Editor: Donna J. Holdridge Website: http:www.arm.gov ACRF Southern Great Plains...

  8. ARM Climate Modeling Best Estimate From Darwin, AU (ARMBE-ATM TWPC3)

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

    McCoy, Renata; Xie, Shaocheng

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  9. ARM Climate Modeling Best Estimate Barrow, AK (ARMBE-ATM NSAC1)

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

    McCoy, Renata; Xie, Shaocheng

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  10. ARM Climate Modeling Best Estimate From Darwin, AU (ARMBE-ATM TWPC2)

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

    McCoy, Renata; Xie, Shaocheng

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  11. ARM Climate Modeling Best Estimate Lamont, OK (ARMBE-ATM SGPC1)

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

    McCoy, Renata; Xie, Shaocheng

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  12. ARM Climate Modeling Best Estimate From Manus Island, PNG (ARMBE-ATM TWPC1)

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

    McCoy, Renata; Xie, Shaocheng

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  13. ARM Climate Modeling Best Estimate Barrow, AK (ARMBE-ATM NSAC1 V4)

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

    McCoy, Renata; Xie, Shaocheng

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  14. ARM Climate Modeling Best Estimate From Nauru (ARMBE-ATM TWPC2)

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

    McCoy, Renata; Xie, Shaocheng

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  15. ARM Climate Modeling Best Estimate From Darwin, AU (ARMBE-ATM...

    Office of Scientific and Technical Information (OSTI)

    The ARM CMBE-ATM Xie, McCoy, Klein et al. data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data. Authors: ...

  16. ARM Climate Modeling Best Estimate Barrow, AK (ARMBE-ATM NSAC1...

    Office of Scientific and Technical Information (OSTI)

    The ARM CMBE-ATM Xie, McCoy, Klein et al. data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data. Authors: ...

  17. ARM Climate Modeling Best Estimate Lamont, OK (ARMBE-ATM SGPC1...

    Office of Scientific and Technical Information (OSTI)

    The ARM CMBE-ATM Xie, McCoy, Klein et al. data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data. Authors: ...

  18. ARM Climate Modeling Best Estimate Lamont, OK (ARMBE-CLDRAD SGPC1)

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

    McCoy, Renata; Xie, Shaocheng

    The ARM CMBE-CLDRAD [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected cloud and radiation relevant quantities from ACRF observations

  19. ARM Climate Modeling Best Estimate from Nauru (ARMBE-CLDRAD TWPC1)

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

    McCoy, Renata; Xie, Shaocheng

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  20. ARM Climate Modeling Best Estimate from Darwin, AU (ARMBE-CLDRAD TWPC3 V2.1)

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

    McCoy, Renata; Xie, Shaocheng

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  1. ARM Climate Modeling Best Estimate from Darwin, AU with additional satellite product (ARMBE-CLDRAD TWPC3 V2.1a)

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

    McCoy, Renata; Xie, Shaocheng

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  2. ARM Climate Modeling Best Estimate from Manus Island, PNG with additional satellite product (ARMBE-CLDRAD TWPC1 V2.1a)

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

    McCoy, Renata; Xie, Shaocheng

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  3. ARM Climate Modeling Best Estimate from Nauru with additional satellite product (ARMBE-CLDRAD TWPC2 V2.1a)

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

    McCoy, Renata; Xie, Shaocheng

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  4. ARM Climate Modeling Best Estimate from Nauru (ARMBE-CLDRAD TWPC3)

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

    McCoy, Renata; Xie, Shaocheng

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  5. ARM Climate Modeling Best Estimate from Manus Island, PNG (ARMBE-CLDRAD TWPC1 V2.1)

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

    McCoy, Renata; Xie, Shaocheng

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  6. ARM Climate Modeling Best Estimate from Nauru (ARMBE-CLDRAD TWPC2)

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

    McCoy, Renata; Xie, Shaocheng

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  7. ARM Climate Modeling Best Estimate Barrow, AK (ARMBE-CLDRAD NSAC1)

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

    McCoy, Renata; Xie, Shaocheng

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  8. ARM Climate Modeling Best Estimate Lamont, OK (ARMBE-CLDRAD SGPC1)

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

    McCoy, Renata; Xie, Shaocheng

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  9. ARM Climate Modeling Best Estimate Barrow, AK with additional satellite product (ARMBE-CLDRAD NSAC1 V2.1a)

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

    McCoy, Renata; Xie, Shaocheng

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  10. ARM Climate Modeling Best Estimate from Nauru (ARMBE-CLDRAD TWPC2 V2.1)

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

    McCoy, Renata; Xie, Shaocheng

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  11. ARM Climate Modeling Best Estimate Barrow, AK (ARMBE-CLDRAD NSAC1 V2.1)

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

    McCoy, Renata; Xie, Shaocheng

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  12. FactSheet-ACRFover.indd

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

    sci- ence in areas such as hydrology, ecology, and weather forecasting to name only a few. ... Costs There is no "fee" for taking advantage of the ACRF scientifi c infrastructure. In ...

  13. Newsletter Southern Great Plains

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

    African Researcher Visits Oklahoma As a follow-up to the ARM Mobile Facility (AMF) ... Niamey, Niger, to the ACRF Southern Great Plains (SGP) site near Lamont, Oklahoma. Dr. ...

  14. ARM Climate Modeling Best Estimate Lamont, OK (ARMBE-ATM SGPC1)

    SciTech Connect (OSTI)

    McCoy, Renata; Xie, Shaocheng

    2012-05-14

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  15. ARM Climate Modeling Best Estimate From Darwin, AU (ARMBE-ATM TWPC2)

    SciTech Connect (OSTI)

    McCoy, Renata; Xie, Shaocheng

    2013-12-26

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  16. ARM Climate Modeling Best Estimate From Manus Island, PNG (ARMBE-ATM TWPC1)

    SciTech Connect (OSTI)

    McCoy, Renata; Xie, Shaocheng

    2013-12-26

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  17. ARM Climate Modeling Best Estimate From Darwin, AU (ARMBE-ATM TWPC3)

    SciTech Connect (OSTI)

    McCoy, Renata; Xie, Shaocheng

    2013-12-27

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  18. ARM Climate Modeling Best Estimate Barrow, AK (ARMBE-ATM NSAC1 V4)

    SciTech Connect (OSTI)

    McCoy, Renata; Xie, Shaocheng

    2013-12-26

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  19. ARM Climate Modeling Best Estimate From Darwin, AU (ARMBE-ATM TWPC3)

    SciTech Connect (OSTI)

    McCoy, Renata; Xie, Shaocheng

    2013-12-26

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  20. turner_poster.arctic_bbhrp.ppt

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

    Rate Profiles over the ACRF NSA Site Dave Turner 1 , Matt Shupe 2 , Dan DeSlover 1 , Eli ... National Laboratory Photo by D. Turner at NSA site, Mar 2007 Introduction A multi-sensor ...

  1. ARM Climate Modeling Best Estimate From Manus Island, PNG (ARMBE-ATM TWPC1)

    SciTech Connect (OSTI)

    McCoy, Renata; Xie, Shaocheng

    2012-05-14

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  2. ARM Climate Modeling Best Estimate Lamont, OK (ARMBE-ATM SGPC1)

    SciTech Connect (OSTI)

    McCoy, Renata; Xie, Shaocheng

    2013-12-26

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  3. ARM Climate Modeling Best Estimate Barrow, AK (ARMBE-ATM NSAC1)

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

    McCoy, Renata; Xie, Shaocheng

    2010-10-05

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  4. ARM Climate Modeling Best Estimate From Darwin, AU (ARMBE-ATM TWPC3)

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

    McCoy, Renata; Xie, Shaocheng

    2010-10-05

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  5. ARM Climate Modeling Best Estimate from Nauru (ARMBE-CLDRAD TWPC2)

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

    McCoy, Renata; Xie, Shaocheng

    2012-05-14

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  6. ARM Climate Modeling Best Estimate Lamont, OK (ARMBE-ATM SGPC1)

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

    McCoy, Renata; Xie, Shaocheng

    2011-12-13

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  7. ARM Climate Modeling Best Estimate Barrow, AK (ARMBE-CLDRAD NSAC1 V2.1)

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

    McCoy, Renata; Xie, Shaocheng

    2010-08-11

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  8. ARM Climate Modeling Best Estimate from Darwin, AU (ARMBE-CLDRAD TWPC3 V2.1)

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

    McCoy, Renata; Xie, Shaocheng

    2010-08-10

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  9. ARM Climate Modeling Best Estimate from Nauru (ARMBE-CLDRAD TWPC1)

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

    McCoy, Renata; Xie, Shaocheng

    2012-05-14

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  10. ARM Climate Modeling Best Estimate Barrow, AK (ARMBE-CLDRAD NSAC1)

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

    McCoy, Renata; Xie, Shaocheng

    2012-05-14

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  11. ARM Climate Modeling Best Estimate From Manus Island, PNG (ARMBE-ATM TWPC1)

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

    McCoy, Renata; Xie, Shaocheng

    2010-10-05

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  12. ARM Climate Modeling Best Estimate from Nauru (ARMBE-CLDRAD TWPC2 V2.1)

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

    McCoy, Renata; Xie, Shaocheng

    2010-08-11

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  13. ARM Climate Modeling Best Estimate from Nauru with additional satellite product (ARMBE-CLDRAD TWPC2 V2.1a)

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

    McCoy, Renata; Xie, Shaocheng

    2011-02-07

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  14. ARM Climate Modeling Best Estimate from Darwin, AU with additional satellite product (ARMBE-CLDRAD TWPC3 V2.1a)

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

    McCoy, Renata; Xie, Shaocheng

    2011-02-07

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  15. ARM Climate Modeling Best Estimate from Nauru (ARMBE-CLDRAD TWPC3)

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

    McCoy, Renata; Xie, Shaocheng

    2012-05-14

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  16. ARM Climate Modeling Best Estimate from Manus Island, PNG with additional satellite product (ARMBE-CLDRAD TWPC1 V2.1a)

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

    McCoy, Renata; Xie, Shaocheng

    2011-02-07

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  17. ARM Climate Modeling Best Estimate from Manus Island, PNG (ARMBE-CLDRAD TWPC1 V2.1)

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

    McCoy, Renata; Xie, Shaocheng

    2011-02-07

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  18. ARM Climate Modeling Best Estimate Lamont, OK (ARMBE-CLDRAD SGPC1)

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

    McCoy, Renata; Xie, Shaocheng

    2012-05-14

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  19. ARM Climate Modeling Best Estimate From Nauru (ARMBE-ATM TWPC2)

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

    McCoy, Renata; Xie, Shaocheng

    2010-10-05

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  20. ARM Climate Modeling Best Estimate Barrow, AK with additional satellite product (ARMBE-CLDRAD NSAC1 V2.1a)

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

    McCoy, Renata; Xie, Shaocheng

    2011-02-07

    The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data.

  1. Research Highlight

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

    Five-Year Statistics of Shallow Clouds at the ACRF SGP Site Download a printable PDF ... 2008. "Temporal variability of fair-weather cumulus statistics at the ARM SGP site." ...

  2. Safety Issues

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

    Site Safety Orientation April, 2015 Atmospheric Radiation Measurement Climate Research Facility/ North Slope of Alaska/Adjacent Arctic Ocean (ACRF/NSA/AAO) Site Safety Orientation Purpose This document provides an overview and summary of safety issues and safe work practices associated with operations at the Atmospheric Radiation Measurement Climate Research Facility/North Slope of Alaska/Adjacent Arctic Ocean (ACRF/NSA/AAO) Sites. It is intended for site visitors as well as routine site

  3. Microsoft Word - Instrument Status - February 2007 formatted_P-07-002.2.doc

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

    2 ACRF Instrumentation Status: New, Current, and Future February 2007 James Liljegren ACRF Instrument Team Coordinator Work supported by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research Summary The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Program Climate Research Facility instrumentation status. The report is divided into four sections: (1) new instrumentation in the process of

  4. Microsoft Word - Instrument Status - January 2007 formatted.doc

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

    ACRF Instrumentation Status: New, Current, and Future January 2007 James Liljegren ACRF Instrument Team Coordinator Work supported by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research Summary The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Program Climate Research Facility instrumentation status. The report is divided into four sections: (1) new instrumentation in the process of

  5. Microsoft Word - Instrument Status - Nov-Dec 2006 formatted .doc

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

    5 ACRF Instrumentation Status: New, Current, and Future November-December 2006 James Liljegren ACRF Instrument Team Coordinator Work supported by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research Summary The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Program Climate Research Facility instrumentation status. The report is divided into four sections: (1) new instrumentation in the

  6. SRRL: Broadband Outdoor Radiometer CALibrations (BORCAL)

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

    Broadband Outdoor Radiometer Calibrations Accurate measurements of solar radiation require regular recalibration of the radiometers used to make the irradiance measurement. NREL has developed the Broadband Outdoor Radiometer Calibration (BORCAL) approach for the annual calibration of pyranometers, pyrheliometers, and pyrgeometers used by the Department of Energy. BORCALs are conducted at the Solar Radiation Research Laboratory (SRRL) and at the Atmospheric Radiation Measurement (ARM) Program's

  7. NREL Particle Receiver Will Enable High-Temperature CSP (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2014-08-01

    Near-blackbody enclosed particle receiver can support high-temperature thermal energy storage and high-efficiency power cycles.

  8. Aspects of the quality of data from the Southern Great Plains (SGP) cloud and radiation testbed (CART) site broadband radiation sensors

    SciTech Connect (OSTI)

    Splitt, M.E.; Wesely, M.L.

    1996-04-01

    A systmatic evaluation of the performance of broadband radiometers at the Radiation Testbed (CART) site is needed to estimate the uncertainties of the irradiance observations. Here, net radiation observed with the net radiometer in the enrgy balance Bowen ratio station at the Central facility is compared with the net radiation computed as the sum of component irradiances recorded by nearby pyranameters and pyrgeometers. In addition, data obtained from the central facility pyranometers, pyrgeometers, and pyrheliometers are examined for April 1994, when intensive operations periods were being carried out. The data used in this study are from central facility radiometers in a solar and infrared observation station, and EBBR station, the so-called `BSRN` set of upward pointing radiometers, and a set of radiometers pointed down at the 25-m level of a 60-m tower.

  9. Atmospheric Radiation Measurement Program Facilities Newsletter - September 1999

    SciTech Connect (OSTI)

    Holdridge, D. J., ed

    1999-09-27

    The Atmospheric Radiation Measurement Program September 1999 Facilities Newsletter discusses the several Intensive Observation Periods (IOPs) that the ARM SGP CART site will host in the near future. Two projects of note are the International Pyrgeometer Intercomparison and the Fall Single Column Model (SCM)/Nocturnal Boundary Layer (NBL) IOP. Both projects will bring many US and international scientists to the SGP CART site to participate in atmospheric research.

  10. ARM - VAP Process - diffcor

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

    Productsdiffcor Documentation & Plots Technical Report Data Management Facility Plots (Quick Looks) ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send VAP : Correction of Diffuse Shortwave Measurements (DIFFCOR) Instrument Categories Derived Quantities and Models The DIFFCORR1DUTT VAP uses two techniques to correct shortwave (SW) data during daytime hours, using information from a collocated pyrgeometer. First, the

  11. ARM - Publications: Science Team Meeting Documents

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

    Comparisons Between Measured and Modeled Longwave Irradiances During Arctic Winter: Results from the Second International Pyrgeometer and Absolute Sky-Scanning Radiometer Comparison (IPARSC-II) Marty, Ch.(a), Storvold, R.(a), Philipona, R.(b), Delamere, J.(c), Dutton, E.(d), Michalsky, J.(e), Stamnes, K.(f), Eide, H.(f), and Stoffel, T.(g), Geophysical Institute, University of Alaska Fairbanks (a), World Radiation Center, Davos, Switzerland (b), Atmospheric and Environmental Research, Boston

  12. 1

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

    Pyrgeometer Calibrations for the Atmospheric Radiation Measurement Program: Updated Approach T. Stoffel and I. Reda National Renewable Energy Laboratory Golden, Colorado J. Hickey The Eppley Laboratory, Inc. Newport, Rhode Island E. Dutton and J. Michalsky National Oceanic and Atmospheric Administration/Geophysical Monitoring Division SUNY-Albany, New York Introduction Accurate measurements of the broadband longwave irradiance at wavelengths between 3.5 and 50 microns are important for

  13. splitt(2)-99.PDF

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

    Improvement in the Assessment of SIRS Broadband Longwave Radiation Data Quality M. E. Splitt University of Utah Salt Lake City, Utah C. P. Bahrmann Cooperative Institute for Meteorological Satellite Studies University of Oklahoma Norman, Oklahoma Introduction Validation of the performance of the Solar Infrared Station (SIRS) pyrgeometers is being conducted for the Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP). Cloud and Radiation Testbed (CART) site extended facilities

  14. Clough-SA

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

    Longwave Broadband QME Based on ARM Pyrgeometer and AERI Measurements S. A. Clough, A. D. Brown, C. Andronache, and E. J. Mlawer Atmospheric and Environmental Research, Inc. Cambridge, Massachusetts T. R. Shippert and D. D. Turner Pacific Northwest National Laboratory Richland, Washington D. C. Tobin, H. E. Revercomb, and R. O. Knuteson University of Maryland College Park, Maryland Introduction Accurate modeling of the downwelling longwave flux at the surface is critical to our understanding of

  15. ARM Climate Research Facility Annual Report 2005

    SciTech Connect (OSTI)

    J. Voyles

    2005-12-31

    Through the ARM Program, the DOE funded the development of several highly instrumented ground stations for studying cloud formation processes and their influence on radiative transfer, and for measuring other parameters that determine the radiative properties of the atmosphere. This scientific infrastructure, and resultant data archive, is a valuable national and international asset for advancing scientific knowledge of Earth systems. In fiscal year (FY) 2003, the DOE designated ARM sites as a national scientific user facility: the ARM Climate Research (ACRF). The ACRF has enormous potential to contribute to a wide range interdisciplinary science in areas such as meteorology, atmospheric aerosols, hydrology, biogeochemical cycling, and satellite validation, to name only a few.

  16. Nauru Island Effect Detection Data Set

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

    Long, Chuck

    2010-07-15

    During Nauru99 it was noted that the island was producing small clouds that advected over the ARM site. The Nauru Island Effect Study was run for 1.5 years and the methodology developed to detect the occurrence. Nauru ACRF downwelling SW, wind direction, and air temperature data are used, along with downwelling SW data from Licor radiometers located on the southern end of the island near the airport landing strip. A statistical analysis and comparison of data from the two locations is used to detect the likely occurrence of an island influence on the Nauru ACRF site data

  17. Issue: K

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

    Issue: K Author: Mark D. Ivey Page 1 of 24 DR 6 / 30 / 2010 ES&H STANDARD OPERATING PROCEDURE (ES&H SOP) Title: ATMOSPHERIC RADIATION MEASUREMENT CLIMATE RESEARCH FACILITY/NORTH SLOPE OF ALASKA/ADJACENT ARCTIC OCEAN (ACRF/NSA/AAO) PROJECT OPERATING PLAN (U) Location: North Slope of Alaska and Adjacent Arctic Ocean Owners: Mark D Ivey, Department 6383, Manager Mark D Ivey, Department 6383, ACRF/NSA/AAO Site Project Manager and Site ES&H Coordinator Document Release or Change History:

  18. June08.doc

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

    8 ANL/EVS/NL-08-06 Technical Contact: Brad W. Orr Phone: 630-252-8665 Email: brad.orr@anl.gov Editor: Donna J. Holdridge Contributor: Lynne Roeder Website: http://www.arm.gov ACRF Southern Great Plains Newsletter is published by Argonne National Laboratory, managed by UChicago Argonne, LLC, for the U.S. Department of Energy under contract number DE-AC02-06CH11357. Interagency Effort Will Measure Carbon Dioxide Profiles Beginning in June, the ARM Climate Research Facility (ACRF) is supporting an

  19. Newsletter Southern Great Plains

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

    5 ANL/ER/NL-05-08 Technical Contact: Brad W. Orr Phone: 630-252-8665 Email: brad.orr@anl.gov Editor: Donna J. Holdridge Website: http://www.arm.gov ACRF Southern Great Plains Newsletter is published by Argonne National Laboratory, managed by The University of Chicago for the U.S. Department of Energy. SGP Hosts Instrument Team Meeting The SGP central facility hosted the biennial ARM Climate Research Facility (ACRF) Instrument Team Meeting on August 2-4, 2005. Almost 50 instrument mentors, site

  20. Newsletter Southern Great Plains

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

    7 ANL/EVS/NL-07-08 Technical Contact: Brad W. Orr Phone: 630-252-8665 Email: brad.orr@anl.gov Editor: Donna J. Holdridge Contributor: Lynne Roeder Website: http://www.arm.gov ACRF Southern Great Plains Newsletter is published by Argonne National Laboratory, managed by UChicago Argonne, LLC, for the U.S. Department of Energy under contract number DE-AC02-06CH11357. ACRF Instrument Team Meets at SGP The ARM Program has had unprecedented success in operating a large array of sophisticated

  1. Nauru Island Effect Detection Data Set

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

    Long, Chuck

    During Nauru99 it was noted that the island was producing small clouds that advected over the ARM site. The Nauru Island Effect Study was run for 1.5 years and the methodology developed to detect the occurrence. Nauru ACRF downwelling SW, wind direction, and air temperature data are used, along with downwelling SW data from Licor radiometers located on the southern end of the island near the airport landing strip. A statistical analysis and comparison of data from the two locations is used to detect the likely occurrence of an island influence on the Nauru ACRF site data

  2. Slide 1

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

    China LIDAR Summary Connor Flynn, PNNL MPLs deployed for AMF campaign Summary of data dispostion MPL polarization technique, implications Visual survey with AMF China supported by 3 MPL systems 2 ACRF MPL Polarized mode May 2008 - Dec 2008 ~100% uptime ACRF MPL Polarized mode May 2008 - Dec 2008 ~100% uptime AMF M1 Shouxian Nanjing (NUIST) MPL Polarized mode Mar 21 2008 - Feb 11 2009 ~88% uptime (>95% from May-Dec 2008) Nanjing (NUIST) MPL Polarized mode Mar 21 2008 - Feb 11 2009 ~88% uptime

  3. Niamey Aerosol Optical Depths

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

    Flynn, Connor

    2008-10-01

    MFRSR irradiance data collected during the ACRF AMF deployment in Niamey, Niger have been used to derive AOD for five wavelength channels of the MFRSR. These data have been corrected to adjust for filter drift over the course of the campaign and contamination due to forward scattering as a result of large dust particles in the atmosphere around Niamey.

  4. Tools for Teaching Climate Change Studies

    SciTech Connect (OSTI)

    Maestas, A.M.; Jones, L.A.

    2005-03-18

    The Atmospheric Radiation Measurement Climate Research Facility (ACRF) develops public outreach materials and educational resources for schools. Studies prove that science education in rural and indigenous communities improves when educators integrate regional knowledge of climate and environmental issues into school curriculum and public outreach materials. In order to promote understanding of ACRF climate change studies, ACRF Education and Outreach has developed interactive kiosks about climate change for host communities close to the research sites. A kiosk for the North Slope of Alaska (NSA) community was installed at the Iupiat Heritage Center in 2003, and a kiosk for the Tropical Western Pacific locales will be installed in 2005. The kiosks feature interviews with local community elders, regional agency officials, and Atmospheric Radiation Measurement (ARM) Program scientists, which highlight both research and local observations of some aspects of environmental and climatic change in the Arctic and Pacific. The kiosks offer viewers a unique opportunity to learn about the environmental concerns and knowledge of respected community elders, and to also understand state-of-the-art climate research. An archive of interviews from the communities will also be distributed with supplemental lessons and activities to encourage teachers and students to compare and contrast climate change studies and oral history observations from two distinct locations. The U.S. Department of Energy's ACRF supports education and outreach efforts for communities and schools located near its sites. ACRF Education and Outreach has developed interactive kiosks at the request of the communities to provide an opportunity for the public to learn about climate change from both scientific and indigenous perspectives. Kiosks include interviews with ARM scientists and provide users with basic information about climate change studies as well as interviews with elders and community leaders

  5. ARM - Datastreams - aeri01ch1

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

    Only measurements considered scientifically relevant are shown below by default. Show all measurements Measurement Units Variable Ambient blackbody temperature - apex K ABBapexte...

  6. ARM - Datastreams - aeri01ch2

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

    Only measurements considered scientifically relevant are shown below by default. Show all measurements Measurement Units Variable Ambient blackbody temperature - apex K ABBapexte...

  7. Arctic Clouds Infrared Imaging Field Campaign Report (Technical...

    Office of Scientific and Technical Information (OSTI)

    This objective was successfully completed with a comparison of the two-year data set calibrated with and without the onboard blackbody. The two different calibration methods ...

  8. ARM - Facility News Article

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

    radiation that falls onto it. This lack of both transmission and reflection properties make blackbodies ideal sources for calibrating instruments that measure...

  9. ARM TR-008

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

    ......... 17 2.30.1 Develop Dynamic Rain Gauge Calibration ... At blackbody temperatures less than -20C, the Dow Corning 200 fluid viscosity increases, ...

  10. EMISSION OF VISIBLE LIGHT BY HOT DENSE METALS By R M. More, M...

    Office of Scientific and Technical Information (OSTI)

    ... It is typically about 10 % of the black-body emission. The droplet calculations are only ... For a uniform metal plate (having constant composition, density and temperature) the ...

  11. Microsoft PowerPoint - 2 McFarlane_VAP Update.ppt

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

    RPWG Breakout Session RPWG Breakout Session RPWG Breakout Session 1:00-1:20 Sally McFarlane - VAP update + aircraft albedo experiment 1:20-1:35 RPWG Priority Discussion Research talks: 1:35 Jennifer Delamere - SW QME update 1:45 Lazaros Oreopoulos - CIRC 1:55 Ibrahim Reda - Recent Results of Pyrgeometer Calibrations Traceable to the World Infrared Standard Group. 2:05 Tom Stoffel - Results of AMF/GNDRAD Reconfiguration on Upwelling Irradiances. 2:10 Jean-Charles Dupont - Observed cirrus cloud

  12. ARM - VAP Product - qmelwflux

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

    Productsqmelwfluxqmelwflux Documentation Data Management Facility Plots (Quick Looks) Citation DOI: 10.5439/1027752 [ What is this? ] Generate Citation ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send VAP Output : QMELWFLUX QME: longwave Flux, between AERI, LBLRTM, RRTM, and the pyrgeometer Active Dates 2001.04.02 - 2003.04.16 Originating VAP Process Comparison of Longwave Flux Data from AERI and LBLRTM vs.

  13. ARM - Datastreams - mwrlos

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

    Base time in Epoch seconds since 1970-1-1 0:00:00 0:00 basetime 23.8 GHz Blackbody signal count bb23 ( time ) 31.4 GHz Blackbody signal counts bb31 ( time ) 23.8 GHz...

  14. Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report July 1 September 30, 2006

    SciTech Connect (OSTI)

    DL Sisterson

    2006-10-01

    Description. Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year dating back to 1998.

  15. ARM Quick-looks Database for North Slope Alaska (NSA) sites

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

    Stamnes, Knut [NSA Site Scientist

    From these pages one can monitor parts of the data acquisition process and access daily data visualizations from the different instruments. These data visualizations are produced in near real time automatically and are called Quick-Looks (QLs). The quick-looks contains unofficial data of unknown quality. Once data is released one can obtain the full data-set from any instrument available, and along with that, a statement about the data quality from the ARM archive. The database provides Quick-looks for the Barrow ACRF site (NSA C1), the Atqasuk ACRF site (NSA C2), or the SHEBA ice campaign of 1997 and 1998. As of 12-17-08, the database had more than 528,000 quick-looks available as data figures and data plots. No password is required for Quick-look access. (Specialized Interface)

  16. Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report July 1 – September 30, 2009

    SciTech Connect (OSTI)

    DL Sisterson

    2009-10-15

    Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real-time. Raw and processed data then are sent approximately daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by 1) individual data stream, site, and month for the current year and 2) site and fiscal year (FY) dating back to 1998.

  17. Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report - July 1 - September 30, 2008

    SciTech Connect (OSTI)

    DL Sisterson

    2008-09-30

    Description. Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real-time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year (FY) dating back to 1998.

  18. Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report January 1 – March 31, 2007

    SciTech Connect (OSTI)

    DL Sisterson

    2007-04-01

    Description. Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year (FY) dating back to 1998.

  19. Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report April 1 - June 30, 2007

    SciTech Connect (OSTI)

    DL Sisterson

    2007-07-01

    Description. Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year (FY) dating back to 1998.

  20. Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report - January 1 - March 31, 2008

    SciTech Connect (OSTI)

    Sisterson, DL

    2008-04-01

    Description. Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year (FY) dating back to 1998.

  1. Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report January 1 - March 31, 2009

    SciTech Connect (OSTI)

    DL Sisterson

    2009-03-17

    Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real-time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year (FY) dating back to 1998.

  2. Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report October 1 - December 31, 2007

    SciTech Connect (OSTI)

    DL Sisterson

    2008-01-08

    Description. Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year (FY) dating back to 1998.

  3. Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report April 1 - June 30, 2008

    SciTech Connect (OSTI)

    DL Sisterson

    2008-06-01

    Description. Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year (FY) dating back to 1998.

  4. Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report April 1 – June 30, 2006

    SciTech Connect (OSTI)

    DL Sisterson

    2006-07-01

    Description. Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year; and (2) site and fiscal year dating back to 1998.

  5. Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report - October 1 - December 31, 2008

    SciTech Connect (OSTI)

    Sisterson, DL

    2009-01-15

    Description. Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real-time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year (FY) dating back to 1998.

  6. Research Highlight

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

    The Vertical Structure of Cloud Radiative Forcing at the ACRF SGP Revealed by 8 Years of Continuous Measurements Submitter: Mace, G., University of Utah Area of Research: Cloud Distributions/Characterizations Working Group(s): Cloud Modeling, Cloud Properties Journal Reference: Accepted to Journal of Climate, 2007. Figure 1. Cloud occurrence, coverage, radiative forcing, and radiation effects over a composite annual cycle that is derived by averaging all observations collected during a

  7. Research Highlight

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

    Minimal Shortwave Anomalous Absorption Found over ACRF Sites Download a printable PDF Submitter: Dong, X., University of Arizona Minnis, P., NASA - Langley Research Center Area of Research: Radiation Processes Working Group(s): Radiative Processes Journal Reference: Dong, X, BA Wielicki, B Xi, Y Hu, GG Mace, S Benson, F Rose, S Kato, T Charlock, and P Minnis. 2008. "Using observations of deep convective systems to constrain atmospheric column absorption of solar radiation in the optically

  8. Research Highlight

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

    Using the ACRF Shortwave Spectrometer to Study the Transition Between Clear and Cloudy Regions Download a printable PDF Submitter: Marshak, A., NASA - Goddard Space Flight Center Chiu, J., University of Reading Knyazikhin, Y., Boston University Pilewskie, P., University of Colorado Wiscombe, W. J., Brookhaven National Laboratory Area of Research: Radiation Processes Working Group(s): Radiative Processes Journal Reference: Chiu C, A Marshak, Y Knyazikhin, P Pilewskie, and W Wiscombe. 2009.

  9. Work plan (Nov

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

    ARM STM Cloud Modeling Working Group Session AGENDA Brief introduction of new ARM funded modeling projects: ---------------------------------------------------------------------------------------------------------- 1:00 pm - 1:05 pm Understanding and Improving CRM and GCM Simulations of Cloud Systems with ARM Observations (Xiaoqing Wu, Iowa State University) 1:05 pm - 1:10 pm Interactions of Cumulus Convection and the Boundary Layer at the Southern Great Plains ACRF (Steve Krueger, University of

  10. ARM - Radiative Heating in Underexplored Bands Campaign (RHUBC)

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

    Related Links RHUBC Home NSA Home ARM Data Discovery Browse Data Experiment Planning RHUBC Proposal Abstract Full Proposal (pdf, 420kb) Science Plan (pdf) Operations Plan (pdf, 144kb) Instruments Contacts News ARM Press Release (Feb. 26, 2007) Images flickr_dots Radiative Heating in Underexplored Bands Campaign (RHUBC) Now available: RHUBC-II website Between February and March 2007 at the ACRF North Slope of Alaska site in Barrow, high-spectral-resolution observations were collected by two

  11. ARM - Research Support for International Polar Year (IPY)

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

    Polar YearResearch Support for International Polar Year (IPY) Research Support International Polar Year Begins at ACRF with 3-week Campaign in Barrow Aerosol Affects on Clouds To Be Studied Yearlong Study to Improve Polar Measurements of Radiative Energy Education Efforts Educational Kiosk CD Available at No Cost-Request Yours Today! POLAR-PALOOZA: Climate science goes on tour! Partnership Extends Support for National Science Teacher Conference Teacher's Domain Combines Culture and Climate Other

  12. ARM - XDC Documentation

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

    Documentation External Data Center Order Data Description of External Data Streams Data Viewers and Plots (selected data sets) XDC Documentation XDC Documentation BNL's ARM Related General Report The monthly reports on work done for the ARM Project. Description of External Data Streams Documentation of External Data-Streams includes sources, measurements, area, time-ranges, contacts, etc. External Projects Contacts Includes information on external projects covering ARM ACRF sites. Instructions

  13. ARM - Education Article

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

    October 15, 2007 [Education] Successful Partnering Produces Award Winning Proposal for Native Education Project Bookmark and Share In July 2007, the National Science Foundation (NSF) awarded funding to a proposal developed by ACRF Education and Outreach and WGBH Boston-public television's pre-eminent production house. The winning project, titled "Engaging Alaska Natives with the Geosciences," will add digital media and teacher professional development resources related to the Arctic

  14. ARM - Education Article

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

    April 9, 2007 [Education] Barrow Teachers Learn About International Polar Year Bookmark and Share Two Barrow teachers, Gary Boen and Imelda Cabana, were sent to the NSTA conference in St. Louis. Science teachers in Barrow, Alaska, know that climate change is something their students can experience simply by stepping out into their own back yards. But that doesn't mean teachers don't need resources and materials to help them engage their students in climate studies. Last month, ACRF Education and

  15. Microsoft Word - 2009-02 Instrument Report_DOE-SC-ARM-P-09.004.2.doc

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

    2 ACRF Instrumentation Status: New, Current, and Future JW Voyles February 2009 Work supported by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. Neither the United States nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness

  16. Microsoft Word - 2009-03 Instrument Report_DOE-SC-ARM-P-09-004.3.doc

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

    3 ACRF Instrumentation Status: New, Current, and Future JW Voyles March 2009 Work supported by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. Neither the United States nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of

  17. Microsoft Word - 2009-04 Instrument Report_DOE-SC-ARM-P=09.004.4.doc

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

    4 ACRF Instrumentation Status and Information JW Voyles April 2009 Work supported by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. Neither the United States nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any

  18. Microsoft Word - 2009-05 Instrument Report DOE-SC-ARM-P-09-004.5.doc

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

    5 ACRF Instrumentation Status and Information JW Voyles May 2009 Work supported by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. Neither the United States nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any

  19. Microsoft Word - 2009-06 Instrument Report_DOE_SC_ARM_P_09_004.6.doc

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

    6 ACRF Instrumentation Status and Information JW Voyles June 2009 Work supported by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. Neither the United States nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any

  20. Microsoft Word - 2009-07 Instrument Report_DOE-SC-ARM-P-09-004.7.doc

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

    7 ACRF Instrumentation Status and Information JW Voyles July 2009 Work supported by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. Neither the United States nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any

  1. Microsoft Word - 2009-08 Instrument Report_DOE-SC-ARM-P-09-004.8.doc

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

    8 ACRF Instrumentation Status and Information JW Voyles August 2009 Work supported by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. Neither the United States nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any

  2. Microsoft Word - 2009-09 Instrument Report_DOE-SC-ARM-P-09-004.9.doc

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

    9 ACRF Instrumentation Status and Information JW Voyles September 2009 Work supported by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. Neither the United States nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any

  3. 1

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

    Factors Controlling the Properties of Multi-Phase Arctic Stratocumulus Clouds A. Fridlind and A. Ackerman National Aeronautics and Space Administration - Ames Research Center Moffett Field, California S. Menon and I. Sednev Lawrence Berkeley National Laboratory Berkeley, California Introduction The October 2004 Multi-Phase Arctic Cloud Experiment (M-PACE) Intensive Operational Period (IOP) at the Atmospheric Radiation Measurement (ARM) Climate Research Facility's (ACRF's) North Slope of Alaska

  4. 1

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

    Real Effect or Artifact of Cloud Cover on Aerosol Optical Thickness? M-J. Jeong and Z. Li Department of Meteorology/Earth System Science Interdisciplinary Center University of Maryland College Park, Maryland Introduction Aerosol measurements over the Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) Southern Great Plains (SGP) site characterize the temporal variability, vertical distribution, and optical properties of aerosols in the region. They were made by the Cimel

  5. 1

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

    Tools for Teaching Climate Change Studies A.M. Maestas and L.A. Jones Los Alamos National Laboratory Los Alamos, New Mexico Introduction The Atmospheric Radiation Measurement Climate Research Facility (ACRF) develops public outreach materials and educational resources for schools. Studies prove that science education in rural and indigenous communities improves when educators integrate regional knowledge of climate and environmental issues into school curriculum and public outreach materials. In

  6. 1

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

    Refurbishment and Upgrade of the Atmospheric Radiation Measurement Raman Lidar D.D. Turner Pacific Northwest National Laboratory Richland, Washington J.E.M. Goldsmith Sandia National Laboratories Livermore, California Introduction The Atmospheric Radiation Measurement Program (ARM) Climate Research Facility (ACRF) Raman lidar (CARL) is an autonomous, turn-key system that profiles water vapor, aerosols, and clouds throughout the diurnal cycle for days without attention (Goldsmith et al. 1998).

  7. 1

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

    Analyses from TWP-ICE C.N. Long and J.H. Mather Pacific Northwest National Laboratory Richland, Washington N. Tapper and J. Beringer Monash University Melbourne, Australia B. Atkinson Australian Bureau of Meteorology Darwin, Australia Introduction Surface data collected during Tropical Warm Pool-International Cloud Experiment (TWP-ICE) includes radiation and standard meteorological measurements at six remote sites, as well as those at the ARM Climate Research Facility (ACRF) Darwin site (Figure

  8. 1

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

    Developments and Accomplishments at the ARM Climate Research Facility Southern Great Plains Site During 2005 B.W. Orr and D.L. Sisterson Argonne National Laboratory Argonne, Illinois D.J. Rusk ARM Climate Research Facility/Southern Great Plains Cherokee Nation Distributors Stilwell, Oklahoma New Instruments New instruments were installed at the ARM Climate Research Facility (ACRF) in 2005. This paper discusses these developments as well as accomplishments that occurred during the year. W-Band

  9. 1

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

    Wave Cloud Radar Upgrades: Review, Status, and Plans K.B. Widener Pacific Northwest National Laboratory Richland, Washington K.P. Moran National Oceanic and Atmospheric Administration- Earth System Research Laboratory-Physical Sciences Division Boulder, Colorado Introduction The Atmospheric Radiation Measurement (ARM) Program currently operates five millimeter-wave cloud radars (MMCRs) at the ARM Climate Research Facility (ACRF) Southern Great Plains (SGP) site, North Slope of Alaska (NSA)

  10. CLASIC OUTLINE

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

    ACRF Field Campaign Proposal RACORO Routine Aerial Vehicle Program (AVP) Clouds with Low Optical Water Depths (CLOWD) Optical Radiative Observations RACORO the Raccoon Steering Committee Andrew Vogelmann 1 , Greg McFarquhar 2 3 4 , John Ogren , Dave Turner , Jennifer Comstock 5 3 5 , Graham Feingold , Chuck Long 1 Brookhaven National Laboratory, 2 University of Illinois, 3 NOAA/Earth System Research Laboratory, 4 University of Wisconsin-Madison, 5 Pacific Northwest National Laboratory Additional

  11. Using Radar, Lidar, and Radiometer measurements to Classify Cloud Type and Study Middle-Level Cloud Properties

    SciTech Connect (OSTI)

    Wang, Zhien

    2006-01-04

    The project is concerned with the characterization of cloud macrophysical and microphysical properties by combining radar, lidar, and radiometer measurements available from the U.S. Department of Energy's ARM Climate Research Facility (ACRF). To facilitate the production of integrated cloud product by applying different algorithms to the ARM data streams, an advanced cloud classification algorithm was developed to classified clouds into eight types at the SGP site based on ground-based active and passive measurements. Cloud type then can be used as a guidance to select an optimal retrieval algorithm for cloud microphysical property retrieval. The ultimate goal of the effort is to develop an operational cloud classification algorithm for ARM data streams. The vision 1 IDL code of the cloud classification algorithm based on the SGP ACRF site observations was delivered to the ARM cloud translator during 2004 ARM science team meeting. Another goal of the project is to study midlevel clouds, especially mixed-phase clouds, by developing new retrieval algorithms using integrated observations at the ACRF sites. Mixed-phase clouds play a particular role in the Arctic climate system. A multiple remote sensor based algorithm, which can provide ice water content and effective size profiles, liquid water path, and layer-mean effective radius of water droplet, was developed to study arctic mixed-phase clouds. The algorithm is applied to long-term ARM observations at the NSA ACRF site. Based on these retrieval results, we are studying seasonal and interannual variations of arctic mixed-phase cloud macro- and micro-physical properties.

  12. PowerPoint Presentation

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

    Energy laboratory managed by UChicago-Argonne, LLC Re-establishment of the MFRSR Calibration Facility at the SGP Dan Nelson 1 , Craig Webb 1 , Joseph Michalsky 2 , Gary Hodges 2 , Piotr Kiedron 2 , Patrick Disterhoft 2 , John Schmelzer 3 , Jerry Berndt 4 1 ACRF/SGP, Cherokee Nation Distributors, Stilwell, OK 2 National Oceanographic and Atmospheric Administration, Boulder, CO 3 Pacific Northwest National Laboratory, Richland, WA 4 Consultant to NOAA, Everett, WA CSPHOT SWS 90/150 GHz Radiometer

  13. PowerPoint Presentation

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

    Spectral Shortwave Quality Measurement Experiment (SW QME) at the Southern Great Plains ACRF J. Delamere, E. Mlawer (AER, Inc.) P. Kiedron (CIRES/U. Colorado) J. Michalsky (NOAA/ESRL/GMD) C. Long, C. Flynn, T. Shippert (PNNL) P. Pilewskie, P. McBride (LASP/U. Colorado) The Shortwave QME Paradigm Critical evaluation of all components of closure study in the shortwave..... * Radiometric measurement quality * Accuracy of calculation (LBLRTM/CHARTS) * Line parameters (HITRAN) * MT_CKD continuum

  14. Slide 1

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

    Participation in CINDY2011 (Cooperative Indian Ocean Experiment on Intraseasonal Variability in Year 2011) and Coordination between CINDY/DYNAMO and AMIE (ACRF MJO Investigation Experiment) Chidong Zhang RSMAS, University of Miami Chris Fairall, Richard Johnson, Mike McPhaden Background I: Importance of the MJO/TIV *Monsoons, ENSO, IODZM *Teleconnections, extratropical circulation/weather * Extreme events (midlat rainfall, tropical storm/cyclones) *Earth's rotation rate, length of the day

  15. Bench-Scale Cross Flow Filtration of

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

    ARM-0707 Report on the ARM Climate Research Facility EXPANSION WORKSHOP October 31 - November 1, 2007 Reston, Virginia Prepared for the U.S. Department of Energy under Contract DE AC05 76RL01830 Pacific Northwest National Laboratory Richland, Washington 99352 DOE/SC-ARM-0707 iii Executive Summary The U.S. Department of Energy (DOE) Office of Science created the Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) within the Office of Biological and Environmental Research

  16. Climate Education Update_Jan07.indd

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

    Editing and Layout: Andrea Maestas LALP-06-073 ACRF Climate Education Update  Climate Education Update by Dr. Hans Verlinde, ARM Scientist In the last year, the subject of climate change at the two poles has been in the news more than ever before. Ice cover in the Arctic is decreasing in extent and area; icebergs are breaking off Antarctica because of thinning ice shelves; permafrost is melting in Alaska, causing ground heaving and destroying roads and houses; bird migratory patterns are

  17. Using Radar, Lidar, and Radiometer measurements to Classify Cloud Type and Study Middle-Level Cloud Properties

    SciTech Connect (OSTI)

    Wang, Zhien

    2010-06-29

    The project is mainly focused on the characterization of cloud macrophysical and microphysical properties, especially for mixed-phased clouds and middle level ice clouds by combining radar, lidar, and radiometer measurements available from the ACRF sites. First, an advanced mixed-phase cloud retrieval algorithm will be developed to cover all mixed-phase clouds observed at the ACRF NSA site. The algorithm will be applied to the ACRF NSA observations to generate a long-term arctic mixed-phase cloud product for model validations and arctic mixed-phase cloud processes studies. To improve the representation of arctic mixed-phase clouds in GCMs, an advanced understanding of mixed-phase cloud processes is needed. By combining retrieved mixed-phase cloud microphysical properties with in situ data and large-scale meteorological data, the project aim to better understand the generations of ice crystals in supercooled water clouds, the maintenance mechanisms of the arctic mixed-phase clouds, and their connections with large-scale dynamics. The project will try to develop a new retrieval algorithm to study more complex mixed-phase clouds observed at the ACRF SGP site. Compared with optically thin ice clouds, optically thick middle level ice clouds are less studied because of limited available tools. The project will develop a new two wavelength radar technique for optically thick ice cloud study at SGP site by combining the MMCR with the W-band radar measurements. With this new algorithm, the SGP site will have a better capability to study all ice clouds. Another area of the proposal is to generate long-term cloud type classification product for the multiple ACRF sites. The cloud type classification product will not only facilitates the generation of the integrated cloud product by applying different retrieval algorithms to different types of clouds operationally, but will also support other research to better understand cloud properties and to validate model simulations. The

  18. ARM - Facility News Article

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

    for Checkup Bookmark and Share During the MWR Intercomparison Study at the SGP site, a liquid nitrogen-filled blackbody target (shown on top of the MWR in the foreground) is...

  19. Vision Office Products

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

    ... of the blackbody (referred to as top and bottom), and one at the apex of the cavity cone. ... temperature monitoring points in the form apex apex bot bot top top hbb T W + T W + T W ...

  20. Search for: All records | Data Explorer

    Office of Scientific and Technical Information (OSTI)

    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. ...

  1. Synchronous identification of friendly targets

    DOE Patents [OSTI]

    Telle, John M.; Roger, Stutz A.

    1998-01-01

    A synchronous communication targeting system for use in battle. The present invention includes a transceiver having a stabilizing oscillator, a synchronous amplifier and an omnidirectional receiver, all in electrical communication with each other. A remotely located beacon is attached to a blackbody radiation source and has an amplitude modulator in electrical communication with a optical source. The beacon's amplitude modulator is set so that the optical source transmits radiation frequency at approximately the same or lower amplitude than that of the blackbody radiation source to which the beacon is attached. The receiver from the transceiver is adapted to receive frequencies approximately at or below blackbody radiation signals and sends such signals to the synchronous amplifier. The synchronous amplifier then rectifies and amplifies those signals which correspond to the predetermined frequency to therefore identify whether the blackbody radiation source is friendly or not.

  2. [Multifractal cloud properties data assessment

    SciTech Connect (OSTI)

    Gautier, C.; Ricchiazzi, P.; Peterson, P.; Lavallee, D. ); Frouin, R.; Lubin, D. ); Lovejoy, S. ); Schertzer, D. )

    1992-05-06

    Our group has been very active over the last year, analyzing a number of data sets to characterize multifractal cloud properties and assess the effects of clouds on surface radiation properties (spectral and broadband). The data sets analyzed include: AVHRR observations of clouds over the ocean, SPOT observations of clouds over the ocean, SSM/I observations of clouds over the ocean, pyranometer data with all-sky photographs, pyrgeometer data all-sky photographs, and spectral surface irradiance all-sky photographs. A number of radiative transfer computations have been performed to help in the interpretation of these observations or provide theoretical guidance for their analysis. Finally 4 number of radiative transfer models have been acquired and tested to prepare for the interpretation of ARM/CART data.

  3. Measuring Broadband IR Irradiance in the Direct Solar Beam (Presentation)

    SciTech Connect (OSTI)

    Reda, I.

    2015-03-01

    Solar and atmospheric science radiometers, e.g. pyranometers, pyrheliometers, and photovoltaic cells are calibrated with traceability to a consensus reference, which is maintained by Absolute Cavity Radiometers (ACRs). The ACR is an open cavity with no window, developed to measure extended broadband direct solar irradiance beyond the ultraviolet and infrared bands below and above 0.2 um and 50 um, respectively. On the other hand, pyranometers and pyrheliometers are developed to measure broadband shortwave irradiance from approximately 0.3 um to 3 um, while the present photovoltaic cells are limited to approximately 0.3 um to 1 um. The broadband mismatch of ACR versus such radiometers causes discrepancy in radiometers' calibration methods that has not been discussed or addressed in the solar and atmospheric science literature. Pyrgeometers are also used for solar and atmospheric science applications and are calibrated with traceability to consensus reference, yet are calibrated during nighttime only, because no consensus reference has yet been established for the daytime longwave irradiance. This poster shows a method to measure the broadband IR irradiance in the direct solar beam from 3 um to 50 um, as a first step that might be used to help develop calibration methods to address the mismatch between broadband ACR and shortwave radiometers, and the lack of a daytime reference for pyrgeometers. The irradiance was measured from sunrise to sunset for 5 days when the sun disk was cloudless; the irradiance varied from approximately 1 Wm-2 to 16 Wm-2 for solar zenith angle from 80 degrees to 16 degrees respectively; estimated uncertainty is 1.5 Wm-2.

  4. Measuring Broadband IR Irradiance in the Direct Solar Beam (Poster)

    SciTech Connect (OSTI)

    Reda, I.; Konings, J.; Xie, Y.; Dooraghi, M.; Sengupta, M.

    2015-03-01

    Solar and atmospheric science radiometers, e.g. pyranometers, pyrheliometers, and photovoltaic cells are calibrated with traceability to a consensus reference, which is maintained by Absolute Cavity Radiometers (ACRs). The ACR is an open cavity with no window, developed to measure extended broadband direct solar irradiance beyond the ultraviolet and infrared bands below and above 0.2 micrometers and 50 micrometers, respectively. On the other hand, pyranometers and pyrheliometers are developed to measure broadband shortwave irradiance from approximately 0.3 micrometers to 3 micrcometers, while the present photovoltaic cells are limited to approximately 0.3 micrometers to 1 micrometers. The broadband mismatch of ACR versus such radiometers causes discrepancy in radiometers' calibration methods that has not been discussed or addressed in the solar and atmospheric science literature. Pyrgeometers are also used for solar and atmospheric science applications and calibrated with traceability to consensus reference, yet calibrated during nighttime only, because no consensus reference has yet been established for the daytime longwave irradiance. This poster shows a method to measure the broadband IR irradiance in the direct solar beam from 3 micrometers to 50 micrometers, as first step that might be used to help develop calibration methods to address the mismatch between broadband ACR and shortwave radiometers, and the lack of a daytime reference for pyrgeometers. The irradiance was measured from sunrise to sunset for 5 days when the sun disk was cloudless; the irradiance varied from approximately 1 Wm-2 to 16 Wm-2 for solar zenith angle from 80 degres to 16 degrees respectively; estimated uncertainty is 1.5 Wm-2.

  5. Sandia VG Template

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

    Company for the United States Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. * DOE/ARM = Dept of Energy/Atmospheric Radiation Measurement, DOE's principal climate research program; www.arm.gov DOE/ARM UAS Plans Through Sandia, DOE/ARM* is putting in place a UAS (Unmanned Aircraft Systems) hosting capability on the North Slope of Alaska ARM Climate Research Facilities (ACRF) already exist at Barrow and Atqasuk; DOE/ARM restricted airspace exists

  6. Research Highlight

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

    CMBE - a New ACRF Data Product for Climate Studies Download a printable PDF Submitter: Xie, S., Lawrence Livermore National Laboratory Area of Research: Cloud Distributions/Characterizations Working Group(s): Cloud Modeling Journal Reference: Xie S, RB McCoy, SA Klein, RT Cederwall, WJ Wiscombe, EE Clothiaux, KL Gaustad, J Golaz, S Hall, MP Jensen, KL Johnson, Y Lin, CN Long, JH Mather, RA McCord, SA McFarlane, G Palanisamy, Y Shi, and DD Turner. 2010. "ARM Climate Modeling Best Estimate

  7. Oct08.doc

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

    8 ANL/EVS/NL-08-10 Technical Contact: Brad W. Orr Phone: 630-252-8665 Email: brad.orr@anl.gov Editor: Donna J. Holdridge Contributor: John Schatz Website: http://www.arm.gov ACRF Southern Great Plains Newsletter is published by Argonne National Laboratory, managed by UChicago Argonne, LLC, for the U.S. Department of Energy under contract number DE-AC02-06CH11357. Leadership Noble County Members Tour SGP Site Members of the non-profit organization Leadership Noble County

  8. ARM - PI Product - Nauru Island Effect Detection Data Set

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

    ProductsNauru Island Effect Detection Data Set ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send PI Product : Nauru Island Effect Detection Data Set During Nauru99 it was noted that the island was producing small clouds that advected over the ARM site. The Nauru Island Effect Study was run for 1.5 years and the methodology developed to detect the occurrence. Nauru ACRF downwelling SW, wind direction, and air

  9. ARM - PI Product - Niamey Aerosol Optical Depths

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

    Aerosol Optical Depths ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send PI Product : Niamey Aerosol Optical Depths MFRSR irradiance data collected during the ACRF AMF deployment in Niamey, Niger have been used to derive AOD for five wavelength channels of the MFRSR. These data have been corrected to adjust for filter drift over the course of the campaign and contamination due to forward scattering as a result of

  10. DOE/SC-ARM/P-07-004

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

    2 ACRF Ingest Software Status: New, Current, and Future Revision 2 A.S. Koontz, S. Choudhury B.D. Ermold K.L. Gaustad September 2007 Work supported by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. Neither the United States nor an agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or

  11. DOE/SC-ARM/P-07-004

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

    3 ACRF Ingest Software Status: New, Current, and Future Revision 3 A.S. Koontz, S. Choudhury B.D. Ermold K.L. Gaustad November 2007 Work supported by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. Neither the United States nor an agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or

  12. DOE/SC-ARM/P-07-004

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

    1 ACRF Ingest Software Status: New, Current, and Future Revision 4 A.S. Koontz, S. Choudhury B.D. Ermold K.L. Gaustad January 2008 Work supported by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. Neither the United States nor an agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or

  13. DOE/SC-ARM/P-07-004

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

    3 ACRF Ingest Software Status: New, Current, and Future Revision 6 A.S. Koontz, S. Choudhury B.D. Ermold N. N. Keck K.L. Gaustad R.C. Perez April 2008 Work supported by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. Neither the United States nor an agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal

  14. DOE/SC-ARM/P-07-004

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

    5 ACRF Ingest Software Status: New, Current, and Future A.S. Koontz, S. Choudhury B.D. Ermold N. N. Keck K.L. Gaustad R.C. Perez June 2008 Work supported by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. Neither the United States nor an agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or

  15. Dec08.doc

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

    8 ANL/EVS/NL-08-12 Technical Contact: Brad W. Orr Phone: 630-252-8665 Email: brad.orr@anl.gov Editor: Donna J. Holdridge Contributor: Lynne Roeder Website: http://www.arm.gov ACRF Southern Great Plains Newsletter is published by Argonne National Laboratory, managed by UChicago Argonne, LLC, for the U.S. Department of Energy under contract number DE-AC02-06CH11357. AMF2 Team Surveys Storm Peak Area The U.S. Department of Energy recently announced the initial deployment of the second ARM Mobile

  16. ARM - Field Campaign - Boundary Layer CO2 Using CW Lidar

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

    govCampaignsBoundary Layer CO2 Using CW Lidar Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Boundary Layer CO2 Using CW Lidar 2005.05.21 - 2005.05.24 Lead Scientist : Michael Dobbs Abstract Overflights Underway at ACRF Southern Great Plains Site (M.Dobbs/J.Liljegren) Science collaborators at ITT Industries and the National Aeronautics and Space Administration (NASA) Langley Research Center (LaRC) conducted flights over the Central

  17. ARM - Field Campaign - MWR Inter-Comparison Study

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

    govCampaignsMWR Inter-Comparison Study ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : MWR Inter-Comparison Study 2006.10.09 - 2006.11.30 Lead Scientist : Maria Cadeddu For data sets, see below. Abstract The principal objective of the campaign was to determine the repeatability of ACRF MWR brightness temperature measurements. Secondary objectives included comparisons of precipitable water vapor (PWV)

  18. ARM - Field Campaign - Small Particles in Cirrus (SPartICus)

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

    govCampaignsSmall Particles in Cirrus (SPartICus) Campaign Links SPARTICUS Website ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Small Particles in Cirrus (SPartICus) 2010.01.01 - 2010.06.30 Lead Scientist : Gerald Mace For data sets, see below. Abstract One of the overarching goals of ACRF is to characterize the properties of clouds so that their representation can be improved in Global Climate Models

  19. CMWG_Plenary_V2.ppt

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

    Reports from the Cloud Modeling Working Group Ann Fridlind, Larry Berg, Tony Del Genio, ChrisAan Jakob, Steve Klein, Steve Krueger, Shaocheng Xie, Minghua Zhang 19 th Annual ARM Science Team MeeAng * Louisville, Kentucky * 31 March 2009 ACRF Data ↔ Modeling Skill * Model intercomparisons - M-PACE (NSA) - TWP-ICE (TWP) - ISDAC (NSA) * Other scienAfic accomplishments * Science plan contribuAons - Priority science quesAons - Data needs M-PACE Intercomparison Wrap-Up * 26 models took part * Two

  20. Icy Cirrus Clouds to Be Studied This Spring

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

    4 Icy Cirrus Clouds to Be Studied This Spring Mid-latitude cirrus clouds, which are composed solely of ice crystals, will be the focus of an intensive operational period (IOP) in April and May 2004 at the ARM Climate Research Facility (ACRF) SGP site. Researchers will be probing the clouds with aircraft-based instruments to gather detailed information about the clouds' physical characteristics. To make measurements in cirrus clouds, which generally form in the atmosphere at and above 20,000 feet

  1. Jan09.doc

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

    9 ANL/EVS/NL-09-01 Technical Contact: Brad W. Orr Phone: 630-252-8665 Email: brad.orr@anl.gov Editor: Donna J. Holdridge Contributor: Lynne Roeder Website: http://www.arm.gov ACRF Southern Great Plains Newsletter is published by Argonne National Laboratory, managed by UChicago Argonne, LLC, for the U.S. Department of Energy under contract number DE-AC02-06CH11357. Routine AVP Clouds with Low Optical Water Depths (CLOWD) Optical Radiative Observations (RACORO) Field Campaign Scheduled at SGP

  2. July08.pdf

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

    8 ANL/EVS/NL-08-07 Technical Contact: Brad W. Orr Phone: 630-252-8665 Email: brad.orr@anl.gov Editor: Donna J. Holdridge Contributor: Lynne Roeder Website: http://www.arm.gov ACRF Southern Great Plains Newsletter is published by Argonne National Laboratory, managed by UChicago Argonne, LLC, for the U.S. Department of Energy under contract number DE-AC02-06CH11357. New Ceilometer Evaluated at Southern Great Plains Site To analyze cloud properties, ARM scientists use data from an instrument called

  3. Newsletter Southern Great Plains

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

    Feb./Mar. 2006 ANL/EVS/NL-06-02 Technical Contact: Brad W. Orr Phone: 630-252-8665 Email: brad.orr@anl.gov Editor: Donna J. Holdridge Website: http://www.arm.gov ACRF Southern Great Plains Newsletter is published by Argonne National Laboratory, managed by The University of Chicago for the U.S. Department of Energy. New Shipping and Receiving Building Dedicated The SGP central facility is operating more efficiently with a newly completed Shipping and Receiving building. The SGP Shipping and

  4. Newsletter Southern Great Plains

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

    7 ANL/EVS/NL-07-01 Technical Contact: Brad W. Orr Phone: 630-252-8665 Email: brad.orr@anl.gov Editor: Donna J. Holdridge Contributor: Lynne Roeder Website: http://www.arm.gov ACRF Southern Great Plains Newsletter is published by Argonne National Laboratory, managed by UChicago Argonne, LLC, for the U.S. Department of Energy under contract number DE-AC02-06CH11357. ARM Archive Sets Record for User Accounts The ARM Archive stores and distributes the large quantities of data generated by routine

  5. Newsletter Southern Great Plains

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

    6 ANL/EVS/NL-06-07 Technical Contact: Brad W. Orr Phone: 630-252-8665 Email: brad.orr@anl.gov Editor: Donna J. Holdridge Website: http://www.arm.gov ACRF Southern Great Plains Newsletter is published by Argonne National Laboratory, managed by UChicago Argonne, LLC, for the U.S. Department of Energy under contract number DE-AC02-06CH11357. Infrared Sky Imager Takes a Shot in the Dark Imaging technologies help scientists correlate and compare visual data with the non-visual data retrieved by

  6. Newsletter Southern Great Plains

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

    7 ANL/EVS/NL-07-09 Technical Contact: Brad W. Orr Phone: 630-252-8665 Email: brad.orr@anl.gov Editor: Donna J. Holdridge Contributor: Lynne Roeder Website: http://www.arm.gov ACRF Southern Great Plains Newsletter is published by Argonne National Laboratory, managed by UChicago Argonne, LLC, for the U.S. Department of Energy under contract number DE-AC02-06CH11357. Multifilter Radiometer Added to Cessna Payload Downward-facing multifilter radiometers (MFRs) are instruments used to measure the

  7. PowerPoint Presentation

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

    CPWG Instruments Group Report Chuck Long With help from: Rich Coulter, Jim Mather, Kevin Widener, Eugene Clothiaux, Jimmy Voyles, Others... Moving forward * New 3-channel MWRs - Purchase of 2 this FY, soliciting bids - Tentative plans for 2/yr until one for each CF and spares are purchased. * Photo-acoustic aerosol absorption instrument in process * Upgrade for the BOM C-Pol radar has gone through On hold * SUNY Oxygen A-band instrument - de-scoped by the ACRF Review Board - Concerns over having

  8. Sep08.doc

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

    8 ANL/EVS/NL-08-09 Technical Contact: Brad W. Orr Phone: 630-252-8665 Email: brad.orr@anl.gov Editor: Donna J. Holdridge Website: http://www.arm.gov ACRF Southern Great Plains Newsletter is published by Argonne National Laboratory, managed by UChicago Argonne, LLC, for the U.S. Department of Energy under contract number DE-AC02-06CH11357. 3D Water Vapor Field Campaign Concludes Researchers from the Colorado State University recently concluded a week-long field experiment at the SGP (August

  9. Southern Great Plains

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

    April 2004 ANL/ER/NL-04-04 Technical Contact: James C. Liljegren Phone: 630-252-9540 Email: jcliljegren@anl.gov Editor: Donna J. Holdridge ACRF Southern Great Plains Newsletter is published by Argonne National Laboratory, an Office of Science laboratory operated by The University of Chicago under contract W-31-109-Eng-38 with the U.S. Department of Energy. Site Operations Manager to Retire Southern Great Plains (SGP) site operations manager Jim Teske has announced that he will retire in October

  10. Southern Great Plains

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

    July 2004 ANL/ER/NL-04-07 Technical Contact: James C. Liljegren Phone: 630-252-9540 Email: jcliljegren@anl.gov Editor: Donna J. Holdridge ACRF Southern Great Plains Newsletter is published by Argonne National Laboratory, an Office of Science laboratory operated by The University of Chicago under contract W-31-109-Eng-38 with the U.S. Department of Energy. Global Dimming: A Hot Climate Topic Global dimming, also referred to as solar dimming, is a new buzz word in the scientific community. Coined

  11. Southern Great Plains

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

    March 2004 ANL/ER/NL-04-03 Technical Contact: James C. Liljegren Phone: 630-252-9540 Email: jcliljegren@anl.gov Editor: Donna J. Holdridge Website: www.arm.gov ACRF Southern Great Plains Newsletter is published by Argonne National Laboratory, an Office of Science laboratory operated by The University of Chicago under contract W-31-109-Eng-38 with the U.S. Department of Energy. 2004 ARM Science Team Meeting Sets Attendance Record A record-breaking 316 scientists and researchers from 22 different

  12. Southern Great Plains

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

    November 2004 ANL/ER/NL-04-11 Technical Contact: James C. Liljegren Phone: 630-252-9540 Email: jcliljegren@anl.gov Editor: Donna J. Holdridge ACRF Southern Great Plains Newsletter is published by Argonne National Laboratory, an Office of Science laboratory operated by The University of Chicago under contract W-31-109-Eng-38 with the U.S. Department of Energy. Flare Field Campaign Aims to Rid Data of Clutter A series of aircraft flares were ignited on the ground at the SGP on October 19 and 20,

  13. Southern Great Plains

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

    September 2004 ANL/ER/NL-04-09 Technical Contact: James C. Liljegren Phone: 630-252-9540 Email: jcliljegren@anl.gov Editor: Donna J. Holdridge ACRF Southern Great Plains Newsletter is published by Argonne National Laboratory, an Office of Science laboratory operated by The University of Chicago under contract W-31-109-Eng-38 with the U.S. Department of Energy. ARM Mobile Facility Will Explore New Locales For some time, scientists have wanted to expand the reach of the ARM Program to additional

  14. Cold Weather Hazards

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

    0 Cold Weather Hazards June 2010 NSA_cwh_Rev10.doc 1 Atmospheric Radiation Measurement Climate Research Facility/ North Slope of Alaska/Adjacent Arctic Ocean (ACRF/NSA/AAO) Cold Weather Hazards Winter Conditions at the North Slope of Alaska The North Slope of Alaska is north of the Arctic Circle at latitudes ranging from 69 to 72 degrees. Barrow, the largest town on the North Slope (pop. 4500), is the site of a National Weather Service Station, which has been active for several decades, so the

  15. DOE national user facility in the Tropical Western Pacific.

    SciTech Connect (OSTI)

    Jones, L. A.; Porch, W. M.; Sisterson, Doug L.; Mather, J. H.; Long, C. N.

    2004-01-01

    In July 2003, the Department of Energy's Office of Biological and Environmental Research designated the Atmospheric Radiation Measurement sites as National User Facilities and renamed them the ARM Climate Research Facility (ACRF). As a result, the former ARM Cloud and Radiation Test bed (CART) sites are now collectively called Climate Research Sites. Part of the conditions associated with funding for ACRF is that the ARM program must attract new users. Located in Australia, and the island nations of Papua New Guinea and the Republic of Nauru, the three Tropical Western Pacific (TWP) research facilities offer unique scientific opportunities to prospective users. Although the locations of the facilities pose significant logistical challenges, particularly the two island sites, the TWP Office addresses these issues so that prospective users can focus on their research. The TWP Office oversees the operation of these sites by collaborating with the governments of Australia, Papua New Guinea, and the Republic of Nauru. Local observers are trained to effectively operate and maintain the facilities, and the state-side TWP Office offers supporting resources including daily instrument monitoring; equipment shipping, inventory tracking; customs coordination; and a readily deployable technical maintenance team at relatively minimal cost to prospective users. Satellite communications allow continuous, near-real time data from all three stations. The TWP Office also works diligently to maintain good local government and community relations with active outreach programs. This paper presents the TWP research facilities as the valuable resources they are to the scientific community.

  16. Atmospheric Radiation Measurement program climate research facility operations quarterly report July 1 - September 30, 2008.

    SciTech Connect (OSTI)

    Sisterson, D. L.

    2008-10-08

    Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real-time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year (FY) dating back to 1998. Table 1 shows the accumulated maximum operation time (planned uptime), actual hours of operation, and variance (unplanned downtime) for the period July 1 - September 30, 2008, for the fixed sites. The AMF has been deployed to China, but the data have not yet been released. The fourth quarter comprises a total of 2,208 hours. The average exceeded our goal this quarter. The Site Access Request System is a web-based database used to track visitors to the fixed and mobile sites, all of which have facilities that can be visited. The NSA locale has the Barrow and Atqasuk sites. The SGP site has a central facility, 23 extended facilities, 4 boundary facilities, and 3 intermediate facilities. The TWP locale has the Manus, Nauru, and Darwin sites. HFE represents the AMF statistics for the Shouxian, China, deployment in 2008. FKB represents the AMF statistics for the Haselbach, Germany, past deployment in 2007. NIM represents the AMF statistics for the Niamey, Niger, Africa, past deployment in 2006. PYE represents just the AMF Archive statistics for the Point Reyes, California, past deployment in 2005. In addition, users who do not want to wait for data to be provided through the ACRF Archive can request a research account on the local site data system. The seven computers for the

  17. Atmospheric Radiation Measurement program climate research facility operations quarterly report January 1 - March 31, 2008.

    SciTech Connect (OSTI)

    Sisterson, D. L.

    2008-05-22

    Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year (FY) dating back to 1998. Table 1 shows the accumulated maximum operation time (planned uptime), actual hours of operation, and variance (unplanned downtime) for the period January 1 - March 31, 2008, for the fixed sites. The AMF is being deployed to China and is not in operation this quarter. The second quarter comprises a total of 2,184 hours. The average as well as the individual site values exceeded our goal this quarter. The Site Access Request System is a web-based database used to track visitors to the fixed and mobile sites, all of which have facilities that can be visited. The NSA locale has the Barrow and Atqasuk sites. The SGP site has a central facility, 23 extended facilities, 4 boundary facilities, and 3 intermediate facilities. The TWP locale has the Manus, Nauru, and Darwin sites. FKB represents the AMF statistics for the Haselbach, Germany, past deployment in 2007. NIM represents the AMF statistics for the Niamey, Niger, Africa, past deployment in 2006. PYE represents just the AMF Archive statistics for the Point Reyes, California, past deployment in 2005. In addition, users who do not want to wait for data to be provided through the ACRF Archive can request a research account on the local site data system. The seven computers for the research accounts are located at the Barrow

  18. Atmospheric Radiation Measurement program climate research facility operations quarterly report October 1 - December 31, 2007.

    SciTech Connect (OSTI)

    Sisterson, D. L.

    2008-01-24

    Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year (FY) dating back to 1998. Table 1 shows the accumulated maximum operation time (planned uptime), actual hours of operation, and variance (unplanned downtime) for the period October 1 - December 31, 2007, for the fixed sites and the mobile site. The AMF has been deployed to Germany and this was the final operational quarter. The first quarter comprises a total of 2,208 hours. Although the average exceeded our goal this quarter, a series of severe weather events (i.e., widespread ice storms) disrupted utility services, which affected the SGP performance measures. Some instruments were covered in ice and power and data communication lines were down for more than 10 days in some areas of Oklahoma and Kansas, which resulted in lost data at the SGP site. The Site Access Request System is a web-based database used to track visitors to the fixed sites, all of which have facilities that can be visited. The NSA locale has the Barrow and Atqasuk sites. The SGP site has a central facility, 23 extended facilities, 4 boundary facilities, and 3 intermediate facilities. The TWP locale has the Manus, Nauru, and Darwin sites. The AMF completed its mission at the end of this quarter in Haselback, Germany (FKB designation). NIM represents the AMF statistics for the Niamey, Niger, Africa, past deployment in 2006. PYE

  19. Atmospheric Radiation Measurement program climate research facility operations quarterly report October 1 - December 31, 2006.

    SciTech Connect (OSTI)

    Sisterson, D. L.

    2007-03-14

    Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year dating back to 1998. Table 1 shows the accumulated maximum operation time (planned uptime), the actual hours of operation, and the variance (unplanned downtime) for the period October 1 through December 31, 2006, for the fixed and mobile sites. Although the AMF is currently up and running in Niamey, Niger, Africa, the AMF statistics are reported separately and not included in the aggregate average with the fixed sites. The first quarter comprises a total of 2,208 hours. For all fixed sites, the actual data availability (and therefore actual hours of operation) exceeded the individual (and well as aggregate average of the fixed sites) operational goal for the first quarter of fiscal year (FY) 2007. The Site Access Request System is a web-based database used to track visitors to the fixed sites, all of which have facilities that can be visited. The NSA locale has the Barrow and Atqasuk sites. The SGP site has a Central Facility, 23 extended facilities, 4 boundary facilities, and 3 intermediate facilities. The TWP locale has the Manus, Nauru, and Darwin sites. NIM represents the AMF statistics for the current deployment in Niamey, Niger, Africa. PYE represents the AMF statistics for the Point Reyes, California, past deployment in 2005. In addition, users who do not want to wait for data to be

  20. Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report April 1 - June 30, 2005

    SciTech Connect (OSTI)

    DL Sisterson

    2005-06-30

    Description. Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory for processing in near real time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year dating back to 1998. The United States Department of Energy requires national user facilities to report time-based operating data. The requirements concern the actual hours of operation (ACTUAL); the estimated maximum operation or uptime goal (OPSMAX), which accounts for planned downtime; and the VARIANCE [1 (ACTUAL/OPSMAX)], which accounts for unplanned downtime. The OPSMAX time for the third quarter for the Southern Great Plains (SGP) site is 2,074.8 hours (0.95 2,184 hours this quarter). The annual OPSMAX for the North Slope Alaska (NSA) site is 1,965.6 hours (0.90 2,184), and that for the Tropical Western Pacific (TWP) site is 1,856.4 hours (0.85 2,184). The OPSMAX time for the ARM Mobile Facility (AMF) is 2,074.8 (0.95 2,184). The differences in OPSMAX performance reflect the complexity of local logistics and the frequency of extreme weather events. It is impractical to measure OPSMAX for each instrument or data stream. Data availability reported here refers to the average of the individual, continuous data streams that have been received by the ACRF Archive. Data not at the Archive are caused by downtime (scheduled or unplanned) of the individual instruments. Therefore, data availability is directly related to individual instrument uptime. Thus, the average percent of data in

  1. Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report July 1 - September 30, 2005

    SciTech Connect (OSTI)

    DL Sisterson

    2005-09-30

    Description. Individual raw data streams from instrumentation at the ACRF fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at PNNL for processing in near real time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year dating back to 1998. The DOE requires national user facilities to report time-based operating data. The requirements concern the actual hours of operation (ACTUAL); the estimated maximum operation or uptime goal (OPSMAX), which accounts for planned downtime; and the VARIANCE [1 (ACTUAL/OPSMAX)], which accounts for unplanned downtime. The OPSMAX time for the third quarter for the Southern Great Plains (SGP) site is 2,097.6 hours (0.95 2,208 hours this quarter). The OPSMAX for the North Slope Alaska (NSA) site is 1,987.2 hours (0.90 2,208), and that for the Tropical Western Pacific (TWP) site is 1,876.8 hours (0.85 2,208). The OPSMAX time for the ARM Mobile Facility (AMF) is 2,097.6 hours (0.95 2,208). The differences in OPSMAX performance reflect the complexity of local logistics and the frequency of extreme weather events. It is impractical to measure OPSMAX for each instrument or data stream. Data availability reported here refers to the average of the individual, continuous data streams that have been received by the ACRF Archive. Data not at the Archive are caused by downtime (scheduled or unplanned) of the individual instruments. Therefore, data availability is directly related to individual instrument uptime. Thus, the average percent of data in the Archive represents the average percent of the time (24 hours per day, 92 days for this quarter) the instruments were operating this

  2. Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report October 1 - December 31, 2005

    SciTech Connect (OSTI)

    Sisterson, DL

    2005-12-31

    Description. Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year dating back to 1998. The U.S. Department of Energy requires national user facilities to report time-based operating data. The requirements concern the actual hours of operation (ACTUAL); the estimated maximum operation or uptime goal (OPSMAX), which accounts for planned downtime; and the VARIANCE [1 – (ACTUAL/OPSMAX)], which accounts for unplanned downtime. The OPSMAX time for the third quarter for the Southern Great Plains (SGP) site is 2,097.6 hours (0.95 × 2,208 hours this quarter). The OPSMAX for the North Slope of Alaska (NSA) locale is 1,987.2 hours (0.90 × 2,208), and that for the Tropical Western Pacific (TWP) locale is 1,876.8 hours (0.85 × 2,208). The OPSMAX time for the ARM Mobile Facility (AMF) is 2,097.6 hours (0.95 × 2,208). The differences in OPSMAX performance reflect the complexity of local logistics and the frequency of extreme weather events. It is impractical to measure OPSMAX for each instrument or data stream. Data availability reported here refers to the average of the individual, continuous data streams that have been received by the ACRF Archive. Data not at the Archive are caused by downtime (scheduled or unplanned) of the individual instruments. Therefore, data availability is directly related to individual instrument uptime. Thus, the average percent

  3. Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report October 1 - December 31, 2004

    SciTech Connect (OSTI)

    Sisterson, DL

    2004-12-31

    Description. Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory for processing in near real time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year dating back to 1998. The United States Department of Energy requires national user facilities to report time-based operating data. The requirements concern the actual hours of operation (ACTUAL); the estimated maximum operation or uptime goal (OPSMAX), which accounts for planned downtime; and the VARIANCE [1 – (ACTUAL/OPSMAX)], which accounts for unplanned downtime. The annual OPSMAX time for the Southern Great Plains (SGP) site is 8,322 hours per year (0.95 × 8,760, the number hours in a year, not including leap year). The annual OPSMAX for the North Slope Alaska (NSA) site is 7,884 hours per year (0.90 × 8,760), and that for the Tropical Western Pacific (TWP) site is 7,446 hours per year (0.85 × 8,760). The differences in OPSMAX performance reflect the complexity of local logistics and the frequency of extreme weather events. It is impractical to measure OPSMAX for each instrument or data stream. Data availability reported here refers to the average of the individual, continuous data streams that have been received by the ACRF Archive. Data not at the Archive are caused by downtime (scheduled or unplanned) of the individual instruments. Therefore, data availability is directly related to individual instrument uptime. Thus, the average percent of data in the Archive represents the

  4. Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report January 1 - March 31, 2005

    SciTech Connect (OSTI)

    Sisterson, DL

    2005-03-31

    Description. Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory for processing in near real time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year dating back to 1998. The United States Department of Energy requires national user facilities to report time-based operating data. The requirements concern the actual hours of operation (ACTUAL); the estimated maximum operation or uptime goal (OPSMAX), which accounts for planned downtime; and the VARIANCE [1 – (ACTUAL/OPSMAX)], which accounts for unplanned downtime. The OPSMAX time for this second quarter for the Southern Great Plains (SGP) site is 2052 hours (0.95 × 2,160 hours this quarter). The annual OPSMAX for the North Slope Alaska (NSA) site is 1944 hours (0.90 × 2,160), and that for the Tropical Western Pacific (TWP) site is 1836 hours (0.85 × 2,160). The differences in OPSMAX performance reflect the complexity of local logistics and the frequency of extreme weather events. It is impractical to measure OPSMAX for each instrument or data stream. Data availability reported here refers to the average of the individual, continuous data streams that have been received by the ACRF Archive. Data not at the Archive are caused by downtime (scheduled or unplanned) of the individual instruments. Therefore, data availability is directly related to individual instrument uptime. Thus, the average percent of data in the Archive represents the average percent of the time (24 hours per day, 90

  5. Atmospheric Radiation Measurement Program Climate Research Facility Operations Cumulative Quarterly Report October 1, 2003 - September 30, 2004

    SciTech Connect (OSTI)

    Sisterson, DL

    2004-09-30

    Description. Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory for processing in near real time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year (FY) dating back to 1998. The United States Department of Energy requires national user facilities to report time-based operating data. The requirements concern the actual hours of operation (ACTUAL); the estimated maximum operation or uptime goal (OPSMAX), which accounts for planned downtime; and the VARIANCE [1 – (ACTUAL/OPSMAX)], which accounts for unplanned downtime. The annual OPSMAX time for the Southern Great Plains (SGP) site is 8,322 hours per year (0.95 × 8,760, the number hours in a year, not including leap year). The annual OPSMAX for the North Slope Alaska (NSA) site is 7,884 hours per year (0.90 × 8,760), and that for the Tropical Western Pacific (TWP) site is 7,446 hours per year (0.85 × 8,760). The differences in OPSMAX performance reflect the complexity of local logistics and the frequency of extreme weather events. It is impractical to measure OPSMAX for each instrument or data stream. Data availability reported here refers to the average of the individual, continuous data streams that have been received by the ACRF Archive. Data not at the Archive are caused by downtime (scheduled or unplanned) of the individual instruments. Therefore, data availability is directly related to individual instrument uptime. Thus, the average percent of data in the Archive represents the

  6. Evaluating cloud retrieval algorithms with the ARM BBHRP framework

    SciTech Connect (OSTI)

    Mlawer,E.; Dunn,M.; Mlawer, E.; Shippert, T.; Troyan, D.; Johnson, K. L.; Miller, M. A.; Delamere, J.; Turner, D. D.; Jensen, M. P.; Flynn, C.; Shupe, M.; Comstock, J.; Long, C. N.; Clough, S. T.; Sivaraman, C.; Khaiyer, M.; Xie, S.; Rutan, D.; Minnis, P.

    2008-03-10

    Climate and weather prediction models require accurate calculations of vertical profiles of radiative heating. Although heating rate calculations cannot be directly validated due to the lack of corresponding observations, surface and top-of-atmosphere measurements can indirectly establish the quality of computed heating rates through validation of the calculated irradiances at the atmospheric boundaries. The ARM Broadband Heating Rate Profile (BBHRP) project, a collaboration of all the working groups in the program, was designed with these heating rate validations as a key objective. Given the large dependence of radiative heating rates on cloud properties, a critical component of BBHRP radiative closure analyses has been the evaluation of cloud microphysical retrieval algorithms. This evaluation is an important step in establishing the necessary confidence in the continuous profiles of computed radiative heating rates produced by BBHRP at the ARM Climate Research Facility (ACRF) sites that are needed for modeling studies. This poster details the continued effort to evaluate cloud property retrieval algorithms within the BBHRP framework, a key focus of the project this year. A requirement for the computation of accurate heating rate profiles is a robust cloud microphysical product that captures the occurrence, height, and phase of clouds above each ACRF site. Various approaches to retrieve the microphysical properties of liquid, ice, and mixed-phase clouds have been processed in BBHRP for the ACRF Southern Great Plains (SGP) and the North Slope of Alaska (NSA) sites. These retrieval methods span a range of assumptions concerning the parameterization of cloud location, particle density, size, shape, and involve different measurement sources. We will present the radiative closure results from several different retrieval approaches for the SGP site, including those from Microbase, the current 'reference' retrieval approach in BBHRP. At the NSA, mixed-phase clouds and

  7. Comptonization signatures in the prompt emission of gamma-ray bursts

    SciTech Connect (OSTI)

    Frontera, F.; Farinelli, R.; Dichiara, S.; Guidorzi, C.; Titarchuk, L. [Dipartimento di Fisicae Scienze della Terra, Universit di Ferrara, Via Saragat 1, I-44100 Ferrara (Italy); Amati, L.; Landi, R., E-mail: frontera@fe.infn.it [INAF, Istituto di Astrofisica Spaziale e Fisica Cosmica, Bologna, Via Gobetti 101, I-40129 Bologna (Italy)

    2013-12-20

    We report results of a systematic study of the broadband (2-2000 keV) time-resolved prompt emission spectra of a sample of gamma-ray bursts (GRBs) detected with both Wide Field Cameras (WFCs) on board the BeppoSAX satellite and the Burst and Transient Source Experiment (BATSE) on board the Compton Gamma Ray Observatory. The main goal of this paper is to test spectral models of the GRB prompt emission that have recently been proposed. In particular, we test a recent photospheric model proposed, i.e., blackbody plus power law, the addition of a blackbody emission to the Band function in the cases in which this function does not fit the data, and a recent Comptonization model. By considering the few spectra for which the simple Band function does not provide a fully acceptable fit to the data, we find a statistically significant better fit by adding a blackbody to this function only in one case. We confirm earlier results found fitting the BATSE spectra alone with a blackbody plus power law. Instead, when the BATSE GRB spectra are joined to those obtained with WFCs (2-28 keV), this model becomes unacceptable in most time intervals in which we subdivide the GRB light curves. We find instead that the Comptonization model is always acceptable, even in the few cases in which the Band function is inconsistent with the data. We discuss the implications of these results.

  8. Cloud Occurrence Frequency at the Barrow, Alaska, ARM Climate Research Facility for 2008 Third Quarter 2009 ARM and Climate Change Prediction Program Metric Report

    SciTech Connect (OSTI)

    M Jensen; K Johnson; JH Mather

    2009-07-14

    Clouds represent a critical component of the Earth’s atmospheric energy balance as a result of their interactions with solar and terrestrial radiation and a redistribution of heat through convective processes and latent heating. Despite their importance, clouds and the processes that control their development, evolution and lifecycle remain poorly understood. Consequently, the simulation of clouds and their associated feedbacks is a primary source of inter-model differences in equilibrium climate sensitivity. An important step in improving the representation of cloud process simulations is an improved high-resolution observational data set of the cloud systems including their time evolution. The first order quantity needed to understand the important role of clouds is the height of cloud occurrence and how it changes as a function of time. To this end, the Atmospheric Radiation Measurement (ARM) Climate Research Facilities (ACRF) suite of instrumentation has been developed to make the observations required to improve the representation of cloud systems in atmospheric models.

  9. Narrow Field of View Zenith Radiometer (NFOV) Handbook

    SciTech Connect (OSTI)

    Chiu, C; Marshak, A; Hodges, G; Barnard, JC; Schmelzer, J

    2008-11-01

    The two-channel narrow field-of-view radiometer (NFOV2) is a ground-based radiometer that looks straight up and measures radiance directly above the instrument at wavelengths of 673 and 870 nm. The field-of-view of the instrument is 1.2 degrees, and the sampling time resolution is one second. Measurements of the NFOV2 have been used to retrieve optical properties for overhead clouds that range from patchy to overcast. With a one-second sampling rate of the NFOV2, faster than almost any other ARM Climate Research Facility (ACRF) instrument, we are able, for the first time, to capture changes in cloud optical properties at the natural time scale of cloud evolution.

  10. Raman Lidar (RL) Handbook

    SciTech Connect (OSTI)

    Newsom, RK

    2009-03-01

    The Raman lidar at the ARM Climate Research Facility (ACRF) Southern Great Plains (SGP) Central Facility (SGPRL) is an active, ground-based laser remote sensing instrument that measures height and time resolved profiles of water vapor mixing ratio and several cloud- and aerosol-related quantities. The system is a non-commercial custom-built instrument developed by Sandia National Laboratories specifically for the ARM Program. It is fully computer automated, and will run unattended for many days following a brief (~5-minute) startup period. The self-contained system (requiring only external electrical power) is housed in a climate-controlled 8’x8’x20’ standard shipping container.

  11. Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report July 1 - September 30, 2007

    SciTech Connect (OSTI)

    DL Sisterson

    2007-10-01

    Description. Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real time. Raw and processed data are then sent daily to the ARM Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year (FY) dating back to 1998.

  12. Contributions of the Atmospheric Radiation Measurement (ARM) Program and the ARM Climate Research Facility to the U.S. Climate Change Science Program

    SciTech Connect (OSTI)

    SA Edgerton; LR Roeder

    2008-09-30

    The Earth’s surface temperature is determined by the balance between incoming solar radiation and thermal (or infrared) radiation emitted by the Earth back to space. Changes in atmospheric composition, including greenhouse gases, clouds, and aerosols can alter this balance and produce significant climate change. Global climate models (GCMs) are the primary tool for quantifying future climate change; however, there remain significant uncertainties in the GCM treatment of clouds, aerosol, and their effects on the Earth’s energy balance. The 2007 assessment (AR4) by the Intergovernmental Panel on Climate Change (IPCC) reports a substantial range among GCMs in climate sensitivity to greenhouse gas emissions. The largest contributor to this range lies in how different models handle changes in the way clouds absorb or reflect radiative energy in a changing climate (Solomon et al. 2007). In 1989, the U.S. Department of Energy (DOE) Office of Science created the Atmospheric Radiation Measurement (ARM) Program within the Office of Biological and Environmental Research (BER) to address scientific uncertainties related to global climate change, with a specific focus on the crucial role of clouds and their influence on the transfer of radiation in the atmosphere. To address this problem, BER has adopted a unique two-pronged approach: * The ARM Climate Research Facility (ACRF), a scientific user facility for obtaining long-term measurements of radiative fluxes, cloud and aerosol properties, and related atmospheric characteristics in diverse climate regimes. * The ARM Science Program, focused on the analysis of ACRF data to address climate science issues associated with clouds, aerosols, and radiation, and to improve GCMs. This report describes accomplishments of the BER ARM Program toward addressing the primary uncertainties related to climate change prediction as identified by the IPCC.

  13. Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report. October 1 - December 31, 2009.

    SciTech Connect (OSTI)

    D. L. Sisterson

    2010-01-12

    Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real-time. Raw and processed data are then sent approximately daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year (FY) dating back to 1998. The U.S. Department of Energy (DOE) requires national user facilities to report time-based operating data. The requirements concern the actual hours of operation (ACTUAL); the estimated maximum operation or uptime goal (OPSMAX), which accounts for planned downtime; and the VARIANCE [1 - (ACTUAL/OPSMAX)], which accounts for unplanned downtime. The OPSMAX time for the first quarter of FY 2010 for the North Slope Alaska (NSA) locale is 1,987.20 hours (0.90 x 2,208); for the Southern Great Plains (SGP) site is 2,097.60 hours (0.95 x 2,208); and for the Tropical Western Pacific (TWP) locale is 1,876.8 hours (0.85 x 2,208). The ARM Mobile Facility (AMF) deployment in Graciosa Island, the Azores, Portugal, continues; its OPSMAX time this quarter is 2,097.60 hours (0.95 x 2,208). The differences in OPSMAX performance reflect the complexity of local logistics and the frequency of extreme weather events. It is impractical to measure OPSMAX for each instrument or data stream. Data availability reported here refers to the average of the individual, continuous data streams that have been received by the Archive. Data not at the Archive are the result of downtime (scheduled or unplanned) of the individual instruments. Therefore, data availability is directly related to

  14. Broadband Outdoor Radiometer Calibration Process for the Atmospheric Radiation Measurement Program

    SciTech Connect (OSTI)

    Dooraghi, Michael

    2015-09-01

    The Atmospheric Radiation Measurement program (ARM) maintains a fleet of monitoring stations to aid in the improved scientific understanding of the basic physics related to radiative feedback processes in the atmosphere, particularly the interactions among clouds and aerosols. ARM obtains continuous measurements and conducts field campaigns to provide data products that aid in the improvement and further development of climate models. All of the measurement campaigns include a suite of solar measurements. The Solar Radiation Research Laboratory at the National Renewable Energy Laboratory supports ARM's full suite of stations in a number of ways, including troubleshooting issues that arise as part of the data-quality reviews; managing engineering changes to the standard setup; and providing calibration services and assistance to the full fleet of solar-related instruments, including pyranometers, pyrgeometers, pyrheliometers, as well as the temperature/relative humidity probes, multimeters, and data acquisition systems that are used in the calibrations performed at the Southern Great Plains Radiometer Calibration Facility. This paper discusses all aspects related to the support provided to the calibration of the instruments in the solar monitoring fleet.

  15. Calibration Systems Final Report

    SciTech Connect (OSTI)

    Myers, Tanya L.; Broocks, Bryan T.; Phillips, Mark C.

    2006-02-01

    The Calibration Systems project at Pacific Northwest National Laboratory (PNNL) is aimed towards developing and demonstrating compact Quantum Cascade (QC) laser-based calibration systems for infrared imaging systems. These on-board systems will improve the calibration technology for passive sensors, which enable stand-off detection for the proliferation or use of weapons of mass destruction, by replacing on-board blackbodies with QC laser-based systems. This alternative technology can minimize the impact on instrument size and weight while improving the quality of instruments for a variety of missions. The potential of replacing flight blackbodies is made feasible by the high output, stability, and repeatability of the QC laser spectral radiance.

  16. Characterization of near-terahertz complementary metal-oxide semiconductor circuits using a Fourier-transform interferometer

    SciTech Connect (OSTI)

    Arenas, D. J.; Shim, Dongha; Koukis, D. I.; Seok, Eunyoung; Tanner, D. B.; O, Kenneth K.

    2011-10-24

    Optical methods for measuring of the emission spectra of oscillator circuits operating in the 400-600 GHz range are described. The emitted power from patch antennas included in the circuits is measured by placing the circuit in the source chamber of a Fourier-transform interferometric spectrometer. The results show that this optical technique is useful for measuring circuits pushing the frontier in operating frequency. The technique also allows the characterization of the circuit by measuring the power radiated in the fundamental and in the harmonics. This capability is useful for oscillator architectures designed to cancel the fundamental and use higher harmonics. The radiated power was measured using two techniques: direct measurement of the power by placing the device in front of a bolometer of known responsivity, and by comparison to the estimated power from blackbody sources. The latter technique showed that these circuits have higher emission than blackbody sources at the operating frequencies, and, therefore, offer potential spectroscopy applications.

  17. Subaru spectroscopy and spectral modeling of Cygnus A

    SciTech Connect (OSTI)

    Merlo, Matthew J.; Perlman, Eric S.; Nikutta, Robert; Packham, Christopher; Elitzur, Moshe; Imanishi, Masatoshi; Levenson, N. A.; Radomski, James T.

    2014-06-10

    We present high angular resolution (?0.''5) MIR spectra of the powerful radio galaxy, Cygnus A (Cyg A), obtained with the Subaru telescope. The overall shape of the spectra agree with previous high angular resolution MIR observations, as well as previous Spitzer spectra. Our spectra, both on and off nucleus, show a deep silicate absorption feature. The absorption feature can be modeled with a blackbody obscured by cold dust or a clumpy torus. The deep silicate feature is best fit by a simple model of a screened blackbody, suggesting that foreground absorption plays a significant, if not dominant, role in shaping the spectrum of Cyg A. This foreground absorption prevents a clear view of the central engine and surrounding torus, making it difficult to quantify the extent the torus attributes to the obscuration of the central engine, but does not eliminate the need for a torus in Cyg A.

  18. THE ARCADE 2 INSTRUMENT

    SciTech Connect (OSTI)

    Singal, J.; Fixsen, D. J.; Kogut, A.; Mirel, P.; Wollack, E.; Levin, S.; Seiffert, M.; Limon, M.; Lubin, P.; Villela, T.; Wuensche, C. A.

    2011-04-01

    The second generation Absolute Radiometer for Cosmology, Astrophysics, and Diffuse Emission (ARCADE 2) instrument is a balloon-borne experiment to measure the radiometric temperature of the cosmic microwave background and Galactic and extragalactic emission at six frequencies from 3 to 90 GHz. ARCADE 2 utilizes a double-nulled design where emission from the sky is compared to that from an external cryogenic full-aperture blackbody calibrator by cryogenic switching radiometers containing internal blackbody reference loads. In order to further minimize sources of systematic error, ARCADE 2 features a cold fully open aperture with all radiometrically active components maintained at near 2.7 K without windows or other warm objects, achieved through a novel thermal design. We discuss the design and performance of the ARCADE 2 instrument in its 2005 and 2006 flights.

  19. High speed infrared radiation thermometer, system, and method

    DOE Patents [OSTI]

    Markham, James R. (Middlefield, CT)

    2002-01-01

    The high-speed radiation thermometer has an infrared measurement wavelength band that is matched to the infrared wavelength band of near-blackbody emittance of ceramic components and ceramic thermal barrier coatings used in turbine engines. It is comprised of a long wavelength infrared detector, a signal amplifier, an analog-to-digital converter, an optical system to collect radiation from the target, an optical filter, and an integral reference signal to maintain a calibrated response. A megahertz range electronic data acquisition system is connected to the radiation detector to operate on raw data obtained. Because the thermometer operates optimally at 8 to 12 .mu.m, where emittance is near-blackbody for ceramics, interferences to measurements performed in turbine engines are minimized. The method and apparatus are optimized to enable mapping of surface temperatures on fast moving ceramic elements, and the thermometer can provide microsecond response, with inherent self-diagnostic and calibration-correction features.

  20. Plasma channel optical pumping device and method

    DOE Patents [OSTI]

    Judd, O.P.

    1983-06-28

    A device and method are disclosed for optically pumping a gaseous laser using blackbody radiation produced by a plasma channel which is formed from an electrical discharge between two electrodes spaced at opposite longitudinal ends of the laser. A preionization device which can comprise a laser or electron beam accelerator produces a preionization beam which is sufficient to cause an electrical discharge between the electrodes to initiate the plasma channel along the preionization path. The optical pumping energy is supplied by a high voltage power supply rather than by the preionization beam. High output optical intensities are produced by the laser due to the high temperature blackbody radiation produced by the plasma channel, in the same manner as an exploding wire type laser. However, unlike the exploding wire type laser, the disclosed invention can be operated in a repetitive manner by utilizing a repetitive pulsed preionization device. 5 figs.

  1. Plasma channel optical pumping device and method

    DOE Patents [OSTI]

    Judd, O'Dean P.

    1983-06-28

    A device and method for optically pumping a gaseous laser using blackbody radiation produced by a plasma channel which is formed from an electrical discharge between two electrodes spaced at opposite longitudinal ends of the laser. A preionization device which can comprise a laser or electron beam accelerator produces a preionization beam which is sufficient to cause an electrical discharge between the electrodes to initiate the plasma channel along the preionization path. The optical pumping energy is supplied by a high voltage power supply rather than by the preionization beam. High output optical intensities are produced by the laser due to the high temperature blackbody radiation produced by the plasma channel, in the same manner as an exploding wire type laser. However, unlike the exploding wire type laser, the disclosed invention can be operated in a repetitive manner by utilizing a repetitive pulsed preionization device.

  2. NREL Particle Receiver Will Enable High-Temperature CSP (Fact Sheet), NREL Highlights in Research & Development, NREL (National Renewable Energy Laboratory)

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

    Near-blackbody enclosed particle receiver can support high-temperature thermal energy storage and high- efficiency power cycles. National Renewable Energy Labora- tory (NREL) scientists are designing and developing an innovative high-temper- ature particle receiver and integrated heat-exchanger system to be used in high-efficiency concentrating solar power (CSP) systems. This configuration is addressing the temperature, efficiency, and cost barriers associated with current molten-salt CSP

  3. Comparative studies of dipole polarizabilities in Sr{sup +}, Ba{sup +}, and Ra{sup +} and their applications to optical clocks

    SciTech Connect (OSTI)

    Sahoo, B. K.; Timmermans, R. G. E.; Das, B. P.; Mukherjee, D.

    2009-12-15

    Static dipole polarizabilities are calculated in the ground and metastable states of Sr{sup +}, Ba{sup +} and Ra{sup +} using the relativistic coupled-cluster method. Trends of the electron correlation effects are investigated in these atomic ions. We also estimate the Stark and black-body radiation shifts from these results for these systems for the transitions proposed for the optical frequency standards and compare them with available experimental data.

  4. Research Highlight

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

    Correction Method for Infrared Detector Confirmed; Error in Clear Sky Bias Condition Remains Unresolved Submitter: Turner, D. D., National Oceanic and Atmospheric Administration Area of Research: Radiation Processes Working Group(s): Radiative Processes Journal Reference: N/A AERI data from January 2004 at the ARM North Slope of Alaska locale shows the observed radiance for two AERI systems with significantly different hot blackbody temperatures. Residuals are within 1% of the ambient radiance

  5. Q&A with Nobelist George Smoot - 2009 BCCP Cosmology Workshop

    ScienceCinema (OSTI)

    George Smoot

    2010-09-01

    July 2009: What happens when dark matter and anti-dark mattter collide? If you were in a gravity free environment, what would happen to time? At the annual Cosmology Workshop at Lawrence Berkeley Lab, Nobelist George Smoot answers these questions and more from high school students and teachers. Dr. Smoot was co-awarded the 2006 Nobel Prize in Physics for the discovery of the blackbody form and anisotropy of the cosmic microwave background radiation.

  6. Simulation of nanosecond pulsed laser ablation of copper samples: A focus on laser induced plasma radiation

    SciTech Connect (OSTI)

    Aghaei, M.; Mehrabian, S.; Tavassoli, S. H.

    2008-09-01

    A thermal model for nanosecond pulsed laser ablation of Cu in one dimension and in ambient gas, He at 1 atm, is proposed in which equations concerning heat conduction in the target and gas dynamics in the plume are solved. These equations are coupled to each other through the energy and mass balances at interface between the target and the vapor and also Knudsen layer conditions. By assumption of local thermal equilibrium, Saha-Eggert equations are used to investigate plasma formation. The shielding effect of the plasma, due to photoionization and inverse bremsstrahlung processes, is considered. Bremsstrahlung and blackbody radiation and spectral emissions of the plasma are also investigated. Spatial and temporal distribution of the target temperature, number densities of Cu and He, pressure and temperature of the plume, bremsstrahlung and blackbody radiation, and also spectral emissions of Cu at three wavelengths (510, 516, and 521 nm) are obtained. Results show that the spectral power of Cu lines has the same pattern as CuI relative intensities from National Institute of Standard and Technology. Investigation of spatially integrated bremsstrahlung and blackbody radiation, and also Cu spectral emissions indicates that although in early times the bremsstrahlung radiation dominates the two other radiations, the Copper spectral emission is the dominant radiation in later times. It should be mentioned that the blackbody radiation has the least values in both time intervals. The results can be used for prediction of the optimum time and position of the spectral line emission, which is applicable in some time resolved spectroscopic techniques such as laser induced breakdown spectroscopy. Furthermore, the results suggest that for distinguishing between the spectral emission and the bremsstrahlung radiation, a spatially resolved spectroscopy can be used instead of the time resolved one.

  7. Radiation Transport

    SciTech Connect (OSTI)

    Urbatsch, Todd James

    2015-06-15

    We present an overview of radiation transport, covering terminology, blackbody raditation, opacities, Boltzmann transport theory, approximations to the transport equation. Next we introduce several transport methods. We present a section on Caseology, observing transport boundary layers. We briefly broach topics of software development, including verification and validation, and we close with a section on high energy-density experiments that highlight and support radiation transport.

  8. Numerical simulations of stripping effects in high-intensity hydrogen ion linacs

    SciTech Connect (OSTI)

    Carneiro, J.-P.; Mustapha, B.; Ostroumov, P.N.; /Argonne

    2008-12-01

    Numerical simulations of H{sup -} stripping losses from blackbody radiation, electromagnetic fields, and residual gas have been implemented into the beam dynamics code TRACK. Estimates of the stripping losses along two high-intensity H{sup -} linacs are presented: the Spallation Neutron Source linac currently being operated at Oak Ridge National Laboratory and an 8 GeV superconducting linac currently being designed at Fermi National Accelerator Laboratory.

  9. Electron Bernstein

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

    Bernstein wave emission from an overdense reversed field pinch plasma P. K. Chattopadhyay, J. K. Anderson, T. M. Biewer, D. Craig, and C. B. Forest a) Department of Physics, University of Wisconsin, Madison, Wisconsin 53706 R. W. Harvey CompX, Del Mar, California 92014 A. P. Smirnov Moscow State University, Moscow, Russia ͑Received 11 October 2001; accepted 20 November 2001͒ Blackbody levels of emission in the electron cyclotron range of frequencies have been observed from an overdense (␻ pe

  10. Cosmic Microwave Background | Argonne National Laboratory

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

    Microwave Background Cosmic Microwave Background Remarkable progress has been made in the characterization of the cosmic microwave background radiation (CMB) over the last several years. It was nearly 30 years after the initial discovery of the CMB by Penzias and Wilson in 1965 before small differences in its intensity were measured by COBE and its spectrum was shown to be a blackbody to high precision. The finding helped motivate the inflation theory for the origin of the universe. In the past

  11. Estimation of radiative properties and temperature distributions in coal-fired boiler furnaces by a portable image processing system

    SciTech Connect (OSTI)

    Li, Wenhao; Lou, Chun; Sun, Yipeng; Zhou, Huaichun

    2011-02-15

    This paper presented an experimental investigation on the estimation of radiative properties and temperature distributions in a 670 t/h coal-fired boiler furnace by a portable imaging processing system. The portable system has been calibrated by a blackbody furnace. Flame temperatures and emissivities were measured by the portable system and equivalent blackbody temperatures were deduced. Comparing the equivalent blackbody temperatures measured by the portable system and the infrared pyrometer, the relative difference is less than 4%. The reconstructed pseudo-instantaneous 2-D temperature distributions in two cross-sections can disclose the combustion status inside the furnace. The measured radiative properties of particles in the furnace proved there is significant scattering in coal-fired boiler furnaces and it can provide useful information for the calculation of radiative heat transfer and numerical simulation of combustion in coal-fired boiler furnaces. The preliminary experimental results show this technology will be helpful for the combustion diagnosis in coal-fired boiler furnaces. (author)

  12. 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

  13. Informal Preliminary Report on Comparisons of Prototype SPN-1 Radiometer to PARSL Measurements

    SciTech Connect (OSTI)

    Long, Charles N.

    2014-06-17

    The prototype SPN-1 has been taking measurements for several months collocated with our PNNL Atmospheric Remote Sensing Laboratory (PARSL) solar tracker mounted instruments at the Pacific Northwest National Laboratory (PNNL) located in Richland, Washington, USA. The PARSL radiometers used in the following comparisons consist of an Eppley Normal Incident Pyrheliometer (NIP) and a shaded Eppley model 8-48 “Black and White” pyrgeometer (B&W) to measure the direct and diffuse shortwave irradiance (SW), respectively. These instruments were calibrated in mid-September by comparison to an absolute cavity radiometer directly traceable to the world standard group in Davos, Switzerland. The NIP calibration was determined by direct comparison, while the B&W was calibrated using the shade/unshade technique. All PARSL data prior to mid-September have been reprocessed using the new calibration factors. The PARSL data are logged as 1-minute averages from 1-second samples. Data used in this report span the time period from June 22 through December 1, 2006. All data have been processed through the QCRad code (Long and Shi, 2006), which itself is a more elaborately developed methodology along the lines of that applied by the Baseline Surface Radiation Network (BSRN) Archive (Long and Dutton, 2004), for quality control. The SPN-1 data are the standard total and diffuse SW values obtained from the analog data port of the instrument. The comparisons use only times when both the PARSL and SPN-1 data passed all QC testing. The data were further processed and analyzed by application of the SW Flux Analysis methodology (Long and Ackerman, 2000; Long and Gaustad, 2004, Long et al., 2006) to detect periods of clear skies, calculate continuous estimates of clear-sky SW irradiance and the effect of clouds on the downwelling SW, and estimate fractional sky cover.

  14. Atmospheric Radiation Measurement program climate research facility operations quarterly report October 1 - December 31, 2008.

    SciTech Connect (OSTI)

    Sisterson, D. L.

    2009-01-15

    Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real-time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, they calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year (FY) dating back to 1998. The US Department of Energy (DOE) requires national user facilities to report time-based operating data. The requirements concern the actual hours of operation (ACTUAL); the estimated maximum operation or uptime goal (OPSMAX), which accounts for planned downtime; and the VARIANCE [1-(ACTUAL/OPSMAX)], which accounts for unplanned downtime. The OPSMAX time for the first quarter of FY 2009 for the Southern Great Plains (SGP) site is 2,097.60 hours (0.95 x 2,208 hours this quarter). The OPSMAX for the North Slope Alaska (NSA) locale is 1,987.20 hours (0.90 x 2,208), and for the Tropical Western Pacific (TWP) locale is 1,876.80 hours (0.85 x 2,208). The OPSMAX time for the ARM Mobile Facility (AMF) is not reported this quarter because the data have not yet been released from China to the DMF for processing. The differences in OPSMAX performance reflect the complexity of local logistics and the frequency of extreme weather events. It is impractical to measure OPSMAX for each instrument or data stream. Data availability reported here refers to the average of the individual, continuous data streams that have been received by the Archive. Data not at the Archive are caused by downtime (scheduled or unplanned) of the individual instruments. Therefore, data availability is

  15. Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report January-March 2006

    SciTech Connect (OSTI)

    Sisterson, DL

    2006-03-31

    Description. Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year; and (2) site and fiscal year dating back to 1998. The U.S. Department of Energy requires national user facilities to report time-based operating data. The requirements concern the actual hours of operation (ACTUAL); the estimated maximum operation or uptime goal (OPSMAX), which accounts for planned downtime; and the VARIANCE [1 – (ACTUAL/OPSMAX)], which accounts for unplanned downtime. The OPSMAX time for the second quarter for the Southern Great Plains (SGP) site is 2,052 hours (0.95 × 2,160 hours this quarter). The OPSMAX for the North Slope Alaska (NSA) locale is 1,944 hours (0.90 × 2,160), and that for the Tropical Western Pacific (TWP) locale is 1,836 hours (0.85 × 2,160). The OPSMAX time for the ARM Mobile Facility (AMF) is 2,052 hours (0.95 × 2,160). The differences in OPSMAX performance reflect the complexity of local logistics and the frequency of extreme weather events. It is impractical to measure OPSMAX for each instrument or data stream. Data availability reported here refers to the average of the individual, continuous data streams that have been received by the Archive. Data not at the Archive are caused by downtime (scheduled or unplanned) of the individual instruments. Therefore, data availability is directly related to individual instrument uptime. Thus, the average percent of data in the

  16. Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report July 1 – September 30, 2008

    SciTech Connect (OSTI)

    Sisterson, DL

    2008-09-30

    Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real-time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year (FY) dating back to 1998. The U.S. Department of Energy (DOE) requires national user facilities to report time-based operating data. The requirements concern the actual hours of operation (ACTUAL); the estimated maximum operation or uptime goal (OPSMAX), which accounts for planned downtime; and the VARIANCE [1 – (ACTUAL/OPSMAX)], which accounts for unplanned downtime. The OPSMAX time for the fourth quarter of FY 2008 for the Southern Great Plains (SGP) site is 2,097.60 hours (0.95 x 2,208 hours this quarter). The OPSMAX for the North Slope Alaska (NSA) locale is 1,987.20 hours (0.90 x 2,208), and for the Tropical Western Pacific (TWP) locale is 1,876.80 hours (0.85 x 2,208). The OPSMAX time for the ARM Mobile Facility (AMF) is not reported this quarter because the data have not yet been released from China to the DMF for processing. The differences in OPSMAX performance reflect the complexity of local logistics and the frequency of extreme weather events. It is impractical to measure OPSMAX for each instrument or data stream. Data availability reported here refers to the average of the individual, continuous data streams that have been received by the Archive. Data not at the Archive are caused by downtime (scheduled or unplanned) of the individual instruments. Therefore, data availability is

  17. Cloud Classes and Radiative Heating profiles at the Manus and Nauru Atmospheric Radiation Measurement (ARM) Sites

    SciTech Connect (OSTI)

    Mather, James H.; McFarlane, Sally A.

    2009-10-07

    The Tropical Western Pacific (TWP) is a convective regime; however, the frequency and depth of convection is dependant on dynamical forcing which exhibits variability on a range of temporal scales and also on location within the region. Manus Island, Papua New Guinea lies in the heart of the western Pacific warm pool region and exhibits frequent deep convection much of the time while Nauru, which lies approximately 20 degrees to the East of Manus, lies in a transition zone where the frequency of convection is dependent on the phase of the El Nino/Southern Oscillation. Because of this difference in dynamical regime, the distribution of clouds and the associated radiative heating is quite different at the two sites. Individual cloud types: boundary layer cumulus, thin cirrus, stratiform convective outflow, do occur at both sites – but with different frequencies. In this study we compare cloud profiles and heating profiles for specific cloud types at these two sites using data from the Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF). Results of this comparison indicate that, while the frequency of specific cloud types differ between the two sites as one would expect, the characteristics of individual cloud classes are remarkably similar. This information could prove to be very useful for applying tropical ARM data to the broader region.

  18. Ice Concentration Retrieval in Stratiform Mixed-phase Clouds Using Cloud Radar Reflectivity Measurements and 1D Ice Growth Model Simulations

    SciTech Connect (OSTI)

    Zhang, Damao; Wang, Zhien; Heymsfield, Andrew J.; Fan, Jiwen; Luo, Tao

    2014-10-01

    Measurement of ice number concentration in clouds is important but still challenging. Stratiform mixed-phase clouds (SMCs) provide a simple scenario for retrieving ice number concentration from remote sensing measurements. The simple ice generation and growth pattern in SMCs offers opportunities to use cloud radar reflectivity (Ze) measurements and other cloud properties to infer ice number concentration quantitatively. To understand the strong temperature dependency of ice habit and growth rate quantitatively, we develop a 1-D ice growth model to calculate the ice diffusional growth along its falling trajectory in SMCs. The radar reflectivity and fall velocity profiles of ice crystals calculated from the 1-D ice growth model are evaluated with the Atmospheric Radiation Measurements (ARM) Climate Research Facility (ACRF) ground-based high vertical resolution radar measurements. Combining Ze measurements and 1-D ice growth model simulations, we develop a method to retrieve the ice number concentrations in SMCs at given cloud top temperature (CTT) and liquid water path (LWP). The retrieved ice concentrations in SMCs are evaluated with in situ measurements and with a three-dimensional cloud-resolving model simulation with a bin microphysical scheme. These comparisons show that the retrieved ice number concentrations are within an uncertainty of a factor of 2, statistically.

  19. Fine-scale Horizontal Structure of Arctic Mixed-Phase Clouds.

    SciTech Connect (OSTI)

    Rambukkange,M.; Verlinde, J.; Elorante, E.; Luke, E.; Kollias, P.; Shupe, M.

    2006-07-10

    Recent in situ observations in stratiform clouds suggest that mixed phase regimes, here defined as limited cloud volumes containing both liquid and solid water, are constrained to narrow layers (order 100 m) separating all-liquid and fully glaciated volumes (Hallett and Viddaurre, 2005). The Department of Energy Atmospheric Radiation Measurement Program's (DOE-ARM, Ackerman and Stokes, 2003) North Slope of Alaska (NSA) ARM Climate Research Facility (ACRF) recently started collecting routine measurement of radar Doppler velocity power spectra from the Millimeter Cloud Radar (MMCR). Shupe et al. (2004) showed that Doppler spectra has potential to separate the contributions to the total reflectivity of the liquid and solid water in the radar volume, and thus to investigate further Hallett and Viddaurre's findings. The Mixed-Phase Arctic Cloud Experiment (MPACE) was conducted along the NSA to investigate the properties of Arctic mixed phase clouds (Verlinde et al., 2006). We present surface based remote sensing data from MPACE to discuss the fine-scale structure of the mixed-phase clouds observed during this experiment.

  20. DUST AND GAS IN THE MAGELLANIC CLOUDS FROM THE HERITAGE HERSCHEL KEY PROJECT. I. DUST PROPERTIES AND INSIGHTS INTO THE ORIGIN OF THE SUBMILLIMETER EXCESS EMISSION

    SciTech Connect (OSTI)

    Gordon, Karl D.; Roman-Duval, Julia; Meixner, Margaret; Bot, Caroline; Babler, Brian; Bernard, Jean-Philippe; Bolatto, Alberto; Jameson, Katherine; Boyer, Martha L.; Clayton, Geoffrey C.; Engelbracht, Charles; Fukui, Yasuo; Galametz, Maud; Galliano, Frederic; Hony, Sacha; Lebouteiller, Vianney; Indebetouw, Remy; Israel, Frank P.; Kawamura, Akiko; and others

    2014-12-20

    The dust properties in the Large and Small Magellanic clouds (LMC/SMC) are studied using the HERITAGE Herschel Key Project photometric data in five bands from 100 to 500?m. Three simple models of dust emission were fit to the observations: a single temperature blackbody modified by a power-law emissivity (SMBB), a single temperature blackbody modified by a broken power-law emissivity (BEMBB), and two blackbodies with different temperatures, both modified by the same power-law emissivity (TTMBB). Using these models, we investigate the origin of the submillimeter excess, defined as the submillimeter emission above that expected from SMBB models fit to observations <200 ?m. We find that the BEMBB model produces the lowest fit residuals with pixel-averaged 500?m submillimeter excesses of 27% and 43% for the LMC and SMC, respectively. Adopting gas masses from previous works, the gas-to-dust ratios calculated from our fitting results show that the TTMBB fits require significantly more dust than are available even if all the metals present in the interstellar medium (ISM) were condensed into dust. This indicates that the submillimeter excess is more likely to be due to emissivity variations than a second population of colder dust. We derive integrated dust masses of (7.3 1.7) 10{sup 5} and (8.3 2.1) 10{sup 4} M {sub ?} for the LMC and SMC, respectively. We find significant correlations between the submillimeter excess and other dust properties; further work is needed to determine the relative contributions of fitting noise and ISM physics to the correlations.

  1. Laser induced rovibrational cooling of the linear polyatomic ion C{sub 2}H{sub 2}{sup +}

    SciTech Connect (OSTI)

    Deb, Nabanita; Heazlewood, Brianna R.; Rennick, Christopher J.; Softley, Timothy P.

    2014-04-28

    The laser-induced blackbody-assisted rotational cooling of a linear polyatomic ion, C{sub 2}H{sub 2}{sup +}, in its {sup 2}? ground electronic state in the presence of the blackbody radiation field at 300 K and 77 K is investigated theoretically using a rate-equations model. Although pure rotational transitions are forbidden in this non-polar species, the ?{sub 5} cis-bending mode is infrared active and the (1-0) band of this mode strongly overlaps the 300 K blackbody spectrum. Hence the lifetimes of state-selected rotational levels are found to be short compared to the typical timescale of ion trapping experiments. The ?{sub 5} (1-0) transition is split by the Renner-Teller coupling of vibrational and electronic angular momentum, and by the spin-orbit coupling, into six principal components and these effects are included in the calculations. In this paper, a rotational-cooling scheme is proposed that involves simultaneous pumping of a set of closely spaced Q-branch transitions on the {sup 2}?{sub 5/2} ? {sup 2}?{sub 3/2} band together with two Q-branch lines in the {sup 2}?{sup +} ? {sup 2}?{sub 1/2} band. It is shown that this should lead to >70% of total population in the lowest rotational level at 300 K and over 99% at 77 K. In principle, the multiple Q-branch lines could be pumped with just two broad-band (??? = 0.43 cm{sup ?1}) infrared lasers.

  2. FY2008 Calibration Systems Final Report

    SciTech Connect (OSTI)

    Cannon, Bret D.; Myers, Tanya L.; Broocks, Bryan T.

    2009-01-01

    The Calibrations project has been exploring alternative technologies for calibration of passive sensors in the infrared (IR) spectral region. In particular, we have investigated using quantum cascade lasers (QCLs) because these devices offer several advantages over conventional blackbodies such as reductions in size and weight while providing a spectral source in the IR with high output power. These devices can provide a rapid, multi-level radiance scheme to fit any nonlinear behavior as well as a spectral calibration that includes the fore-optics, which is currently not available for on-board calibration systems.

  3. Laser-induced light emission from carbon nanoparticles

    SciTech Connect (OSTI)

    Osswald, S.; Behler, K.; Gogotsi, Y.

    2008-10-01

    Strong absorption of light in a broad wavelength range and poor thermal conductance between particles of carbon nanomaterials, such as nanotubes, onions, nanodiamond, and carbon black, lead to strong thermal emission (blackbody radiation) upon laser excitation, even at a very low (milliwatts) power. The lasers commonly used during Raman spectroscopy characterization of carbon can cause sample heating to very high temperatures. While conventional thermometry is difficult in the case of nanomaterials, Raman spectral features, such as the G band of graphitic carbon and thermal emission spectra were used to estimate the temperature during light emission that led to extensive graphitization and evaporation of carbon nanomaterials, indicating local temperatures exceeding 3500 deg. C.

  4. Search for Linear Polarization of the Cosmic Background Radiation

    DOE R&D Accomplishments [OSTI]

    Lubin, P. M.; Smoot, G. F.

    1978-10-01

    We present preliminary measurements of the linear polarization of the cosmic microwave background (3 deg K blackbody) radiation. These ground-based measurements are made at 9 mm wavelength. We find no evidence for linear polarization, and set an upper limit for a polarized component of 0.8 m deg K with a 95% confidence level. This implies that the present rate of expansion of the Universe is isotropic to one part in 10{sup 6}, assuming no re-ionization of the primordial plasma after recombination

  5. Detailed balance limit of power conversion efficiency for organic photovoltaics

    SciTech Connect (OSTI)

    Seki, Kazuhiko; Furube, Akihiro; Yoshida, Yuji

    2013-12-16

    A fundamental difference between inorganic photovoltaic (IPV) and organic photovoltaic (OPV) cells is that charges are generated at the interface in OPV cells, while free charges can be generated in the bulk in IPV cells. In OPV cells, charge generation involves intrinsic energy losses to dissociate excitons at the interface between the donor and acceptor. By taking into account the energy losses, we show the theoretical limits of the power conversion efficiency set by radiative recombination of the carriers on the basis of the detailed balance relation between radiation from the cell and black-body radiation.

  6. High-Performance Nanostructured Coating

    Broader source: Energy.gov [DOE]

    The High-Performance Nanostructured Coating fact sheet details a SunShot project led by a University of California, San Diego research team working to develop a new high-temperature spectrally selective coating for receiver surfaces. These receiver surfaces, used in concentrating solar power systems, rely on high-temperature SSCs to effectively absorb solar energy without emitting much blackbody radiation.The optical properties of the SSC directly determine the efficiency and maximum attainable temperature of solar receivers, which in turn influence the power-conversion efficiency and overall system cost.

  7. Optimized Phosphors for Warm White LED Light Engines

    SciTech Connect (OSTI)

    Setlur, Anant; Brewster, Megan; Garcia, Florencio; Hill, M. Christine; Lyons, Robert; Murphy, James; Stecher, Tom; Stoklosa, Stan; Weaver, Stan; Happek, Uwe; Aesram, Danny; Deshpande, Anirudha

    2012-07-30

    The objective of this program is to develop phosphor systems and LED light engines that have steady-state LED efficacies (using LEDs with a 60% wall-plug efficiency) of 105–120 lm/W with correlated color temperatures (CCT) ~3000 K, color rendering indices (CRI) >85, <0.003 distance from the blackbody curve (dbb), and <2% loss in phosphor efficiency under high temperature, high humidity conditions. In order to reach these goals, this involves the composition and processing optimization of phosphors previously developed by GE in combination with light engine package modification.

  8. Spin-1/2 Optical Lattice Clock

    SciTech Connect (OSTI)

    Lemke, N. D.; Ludlow, A. D.; Barber, Z. W.; Fortier, T. M.; Diddams, S. A.; Jiang, Y.; Jefferts, S. R.; Heavner, T. P.; Parker, T. E.; Oates, C. W.

    2009-08-07

    We experimentally investigate an optical clock based on {sup 171}Yb (I=1/2) atoms confined in an optical lattice. We have evaluated all known frequency shifts to the clock transition, including a density-dependent collision shift, with a fractional uncertainty of 3.4x10{sup -16}, limited principally by uncertainty in the blackbody radiation Stark shift. We measured the absolute clock transition frequency relative to the NIST-F1 Cs fountain clock and find the frequency to be 518 295 836 590 865.2(0.7) Hz.

  9. Characterization of near-terahertz complementary metal-oxide semiconductor circuits using a Fourier-transform interferometer

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

    Arenas, D. J.; Shim, Dongha; Koukis, D. I.; Seok, Eunyoung; Tanner, D. B.; O, Kenneth K.

    2011-10-24

    Optical methods for measuring of the emission spectra of oscillator circuits operating in the 400-600 GHz range are described. The emitted power from patch antennas included in the circuits is measured by placing the circuit in the source chamber of a Fourier-transform interferometric spectrometer. The results show that this optical technique is useful for measuring circuits pushing the frontier in operating frequency. The technique also allows the characterization of the circuit by measuring the power radiated in the fundamental and in the harmonics. This capability is useful for oscillator architectures designed to cancel the fundamental and use higher harmonics. Themore » radiated power was measured using two techniques: direct measurement of the power by placing the device in front of a bolometer of known responsivity, and by comparison to the estimated power from blackbody sources. The latter technique showed that these circuits have higher emission than blackbody sources at the operating frequencies, and, therefore, offer potential spectroscopy applications.« less

  10. Optical emission line monitor with background observation and cancellation

    DOE Patents [OSTI]

    Goff, D.R.; Notestein, J.E.

    1985-01-04

    A fiber optics based optical emission line monitoring system is provided in which selected spectral emission lines, such as the sodium D-line emission in coal combustion, may be detected in the presence of interferring background or blackbody radiation with emissions much greater in intensity than that of the emission line being detected. A bifurcated fiber optic light guide is adapted at the end of one branch to view the combustion light which is guided to a first bandpass filter, adapted to the common trunk end of the fiber. A portion of the light is reflected back through the common trunk portion of the fiber to a second bandpass filter adapted to the end of the other branch of the fiber. The first filter bandpass is centered at a wavelength corresponding to the emission line to be detected with a bandwidth of about three nanometers (nm). The second filter is centered at the same wavelength but having a width of about 10 nm. First and second light detectors are located to view the light passing through the first and second filters respectively. Thus, the second detector is blind to the light corresponding to the emission line of interest detected by the first detector and the difference between the two detector outputs is uniquely indicative of the intensity of only the combustion flame emission of interest. This instrument can reduce the effects of interfering blackbody radiation by greater than 20 dB.

  11. Optical emission line monitor with background observation and cancellation

    DOE Patents [OSTI]

    Goff, David R.; Notestein, John E.

    1986-01-01

    A fiber optics based optical emission line monitoring system is provided in which selected spectral emission lines, such as the sodium D-line emission in coal combustion, may be detected in the presence of interferring background or blackbody radiation with emissions much greater in intensity than that of the emission line being detected. A bifurcated fiber optic light guide is adapted at the end of one branch to view the combustion light which is guided to a first bandpass filter, adapted to the common trunk end of the fiber. A portion of the light is reflected back through the common trunk portion of the fiber to a second bandpass filter adapted to the end of the other branch of the fiber. The first filter bandpass is centered at a wavelength corresponding to the emission line to be detected with a bandwidth of about three nanometers (nm). The second filter is centered at the same wavelength but having a width of about 10 nm. First and second light detectors are located to view the light passing through the first and second filters respectively. Thus, the second detector is blind to the light corresponding to the emission line of interest detected by the first detector and the difference between the two detector outputs is uniquely indicative of the intensity of only the combustion flame emission of interest. This instrument can reduce the effects of interferring blackbody radiation by greater than 20 dB.

  12. IRAS-based whole-sky upper limit on Dyson Spheres

    SciTech Connect (OSTI)

    Carrigan, Richard A., Jr.; /Fermilab

    2008-09-01

    A Dyson Sphere is a hypothetical construct of a star purposely cloaked by a thick swarm of broken-up planetary material to better utilize all of the stellar energy. A clean Dyson Sphere identification would give a significant signature for intelligence at work. A search for Dyson Spheres has been carried out using the 250,000 source database of the IRAS infrared satellite which covered 96% of the sky. The search has used the Calgary data collection of the IRAS Low Resolution Spectrometer (LRS) to look for fits to blackbody spectra. Searches have been conducted for both pure (fully cloaked) and partial Dyson Spheres in the blackbody temperature region 100 {le} T {le} 600 K. Other stellar signatures that resemble a Dyson Sphere are reviewed. When these signatures are used to eliminate sources that mimic Dyson Spheres very few candidates remain and even these are ambiguous. Upper limits are presented for both pure and partial Dyson Spheres. The sensitivity of the LRS was enough to find solar-sized Dyson Spheres out to 300 pc, a reach that encompasses a million solar-type stars.

  13. TWO-DIMENSIONAL MAPPING OF YOUNG STARS IN THE INNER 180 pc OF NGC 1068: CORRELATION WITH MOLECULAR GAS RING AND STELLAR KINEMATICS

    SciTech Connect (OSTI)

    Storchi-Bergmann, Thaisa; Riffel, Rogerio; Vale, Tiberio Borges; Riffel, Rogemar A.; Diniz, Marlon R.; McGregor, Peter J.

    2012-08-20

    We report the first two-dimensional mapping of the stellar population and non-stellar continua within the inner 180 pc (radius) of NGC 1068 at a spatial resolution of 8 pc, using integral field spectroscopy in the near-infrared. We have applied the technique of spectral synthesis to data obtained with the instrument NIFS and the adaptive optics module ALTAIR at the Gemini North Telescope. Two episodes of recent star formation are found to dominate the stellar population contribution: the first occurred 300 Myr ago, extending over most of the nuclear region; the second occurred just 30 Myr ago, in a ring-like structure at Almost-Equal-To 100 pc from the nucleus, where it is coincident with an expanding ring of H{sub 2} emission. Inside the ring, where a decrease in the stellar velocity dispersion is observed, the stellar population is dominated by the 300 Myr age component. In the inner 35 pc, the oldest age component (age {>=} 2 Gyr) dominates the mass, while the flux is dominated by blackbody components with temperatures in the range 700 K {<=} T {<=} 800 K which we attribute to the dusty torus. We also find some contribution from blackbody and power-law components beyond the nucleus which we attribute to dust emission and scattered light.

  14. Modulation and amplification of radiative far field heat transfer: Towards a simple radiative thermal transistor

    SciTech Connect (OSTI)

    Joulain, Karl; Ezzahri, Younès; Drevillon, Jérémie; Ben-Abdallah, Philippe

    2015-03-30

    We show in this article that phase change materials (PCM) exhibiting a phase transition between a dielectric state and a metallic state are good candidates to perform modulation as well as amplification of radiative thermal flux. We propose a simple situation in plane parallel geometry where a so-called radiative thermal transistor could be achieved. In this configuration, we put a PCM between two blackbodies at different temperatures. We show that the transistor effect can be achieved easily when this material has its critical temperature between the two blackbody temperatures. We also see that the more the material is reflective in the metallic state, the more switching effect is realized, whereas the more PCM transition is stiff in temperature, the more thermal amplification is high. We finally take the example of VO{sub 2} that exhibits an insulator-metallic transition at 68 °C. We show that a demonstrator of a radiative transistor could easily be achieved in view of the heat flux levels predicted. Far-field thermal radiation experiments are proposed to back the results presented.

  15. Polarized mid-infrared synchrotron emission in the core of Cygnus A

    SciTech Connect (OSTI)

    Lopez-Rodriguez, E.; Packham, C.; Tadhunter, C.; Mason, R.; Perlman, E.; Alonso-Herrero, A.; Ramos Almeida, C.; Rodrguez-Espinosa, J. M.; Levenson, N. A.; lvarez, C. A.; Ramrez, E. A.; Telesco, C. M.

    2014-10-01

    We present high-angular (?0.''4) resolution mid-infrared (MIR) polarimetric observations in the 8.7 ?m and 11.6 ?m filters of Cygnus A using CanariCam on the 10.4 m Gran Telescopio CANARIAS. A highly polarized nucleus is observed with a degree of polarization of 11% 3% and 12% 3% and a position angle of polarization of 27 8 and 35 8 in a 0.''38 (?380 pc) aperture for each filter. The observed rising of the polarized flux density with increasing wavelength is consistent with synchrotron radiation from the parsec-scale jet close to the core of Cygnus A. Based on our polarization model, the synchrotron emission from the parsec-scale jet is estimated to be 14% and 17% of the total flux density in the 8.7 ?m and 11.6 ?m filters, respectively. A blackbody component with a characteristic temperature of 220 K accounts for >75% of the observed MIR total flux density. The blackbody emission arises from a combination of (1) dust emission in the torus; and (2) diffuse dust emission around the nuclear region, but the contributions of the two components cannot be well-constrained in these observations.

  16. Experiments and Modeling of High Altitude Chemical Agent Release

    SciTech Connect (OSTI)

    Nakafuji, G.; Greenman, R.; Theofanous, T.

    2002-07-08

    Using ASCA data, we find, contrary to other researchers using ROSAT data, that the X-ray spectra of the VY Scl stars TT Ari and KR Aur are poorly fit by an absorbed blackbody model but are well fit by an absorbed thermal plasma model. The different conclusions about the nature of the X-ray spectrum of KR Aur may be due to differences in the accretion rate, since this Star was in a high optical state during the ROSAT observation, but in an intermediate optical state during the ASCA observation. TT Ari, on the other hand, was in a high optical state during both observations, so directly contradicts the hypothesis that the X-ray spectra of VY Sol stars in their high optical states are blackbodies. Instead, based on theoretical expectations and the ASCA, Chandra, and XMM spectra of other nonmagnetic cataclysmic variables, we believe that the X-ray spectra of VY Sol stars in their low and high optical states are due to hot thermal plasma in the boundary layer between the accretion disk and the surface of the white dwarf, and appeal to the acquisition of Chandra and XMM grating spectra to test this prediction.

  17. Pigmented foils for radiative cooling and condensation irrigation

    SciTech Connect (OSTI)

    Nilsson, T.M.J.; Vargas, W.E.; Niklasson, G.A.

    1994-12-31

    This paper reports on the development of pigmented polyethylene foils for radiative cooling. The optical properties of the foils were optimized for applications in day-time radiative cooling and water condensation. The authors first study highly scattering foils used as convection shields. These cover foils combine a high solar reflectance and a high transmittance in the atmospheric window region in the infrared. Different pigment materials were studied and ZnS was the only one that could prevent heating of an underlying blackbody at noon, with the sun in its zenith. A 400 {micro}m thick ZnS pigmented polyethylene foil with a pigment volume fraction of 0.15 was tested in Tanzania. At noon the observed temperature of the covered blackbody was only 1.5 K above the ambient. Secondly, they study the potential for condensation of water in an arid region. Pigmented foils for this purpose should combine a high solar reflectance and a high infrared emittance, in order to promote condensation by the radiative cooling effect. Titanium dioxide is a fairly good infrared emitter, but the emittance can be improved by using a mixture of TiO{sub 2} and BaSO{sub 4} pigments or only employing a composite SiO{sub 2}/TiO{sub 2}. Field tests with a 390 {micro}m thick polyethylene foil with TiO{sub 2} and BaSO{sub 4} pigments gave encouraging results.

  18. X-RAY SPECTRAL COMPONENTS OBSERVED IN THE AFTERGLOW OF GRB130925A

    SciTech Connect (OSTI)

    Bellm, Eric C.; Forster, Karl; Harrison, Fiona A.; Madsen, Kristin K.; Perley, Daniel A.; Rana, Vikram R.; Barrire, Nicolas M.; Boggs, Steven E.; Craig, William W.; Bhalerao, Varun; Cenko, S. Bradley; Christensen, Finn E.; Fryer, Chris L.; Hailey, Charles J.; Horesh, Assaf; Ofek, Eran O.; Kouveliotou, Chryssa; Reynolds, Stephen P.; Stern, Daniel; and others

    2014-04-01

    We have identified spectral features in the late-time X-ray afterglow of the unusually long, slow-decaying GRB130925A using NuSTAR, Swift/X-Ray Telescope, and Chandra. A spectral component in addition to an absorbed power law is required at >4? significance, and its spectral shape varies between two observation epochs at 2 10{sup 5} and 10{sup 6}s after the burst. Several models can fit this additional component, each with very different physical implications. A broad, resolved Gaussian absorption feature of several keV width improves the fit, but it is poorly constrained in the second epoch. An additive blackbody or second power-law component provide better fits. Both are challenging to interpret: the blackbody radius is near the scale of a compact remnant (10{sup 8}cm), while the second power-law component requires an unobserved high-energy cutoff in order to be consistent with the non-detection by Fermi/Large Area Telescope.

  19. NuSTAR OBSERVATIONS OF THE MAGNETAR 1E 2259+586

    SciTech Connect (OSTI)

    Vogel, Julia K.; Hascot, Romain; Kaspi, Victoria M.; An, Hongjun; Archibald, Robert; Beloborodov, Andrei M.; Boggs, Steven E.; Christensen, Finn E.; Craig, William W.; Gotthelf, Eric V.; Grefenstette, Brian W.; Hailey, Charles J.; Harrison, Fiona A.; Kennea, Jamie A.; Madsen, Kristin K.; Pivovaroff, Michael J.; Stern, Daniel; Zhang, William W.

    2014-07-01

    We report on new broad band spectral and temporal observations of the magnetar 1E 2259+586, which is located in the supernova remnant CTB 109. Our data were obtained simultaneously with the Nuclear Spectroscopic Telescope Array (NuSTAR) and Swift, and cover the energy range from 0.5-79 keV. We present pulse profiles in various energy bands and compare them to previous RXTE results. The NuSTAR data show pulsations above 20 keV for the first time and we report evidence that one of the pulses in the double-peaked pulse profile shifts position with energy. The pulsed fraction of the magnetar is shown to increase strongly with energy. Our spectral analysis reveals that the soft X-ray spectrum is well characterized by an absorbed double blackbody or blackbody plus power-law model in agreement with previous reports. Our new hard X-ray data, however, suggest that an additional component, such as a power law, is needed to describe the NuSTAR and Swift spectrum. We also fit the data with the recently developed coronal outflow model by Beloborodov for hard X-ray emission from magnetars. The outflow from a ring on the magnetar surface is statistically preferred over outflow from a polar cap.

  20. Designing of Metallic Photonic Structures and Applications

    SciTech Connect (OSTI)

    Yong-Sung Kim

    2006-08-09

    In this thesis our main interest has been to investigate metallic photonic crystal and its applications. We explained how to solve a periodic photonic structure with transfer matrix method and when and how to use modal expansion method. Two different coating methods were introduced, modifying a photonic structure's intrinsic optical properties and rigorous calculation results are presented. Two applications of metallic photonic structures are introduced. For thermal emitter, we showed how to design and find optimal structure. For conversion efficiency increasing filter, we calculated its efficiency and the way to design it. We presented the relation between emitting light spectrum and absorption and showed the material and structural dependency of the absorption spectrum. By choosing a proper base material and structural parameters, we can design a selective emitter at a certain region we are interested in. We have developed a theoretical model to analyze a blackbody filament enclosed by a metallic mesh which can increase the efficiency of converting a blackbody radiation to visible light. With this model we found that a square lattice metallic mesh enclosing a filament might increase the efficiency of incandescent lighting sources. Filling fraction and thickness dependency were examined and presented. Combining these two parameters is essential to achieve the maximum output result.

  1. Single-fiber multi-color pyrometry

    DOE Patents [OSTI]

    Small, IV, Ward; Celliers, Peter

    2000-01-01

    This invention is a fiber-based multi-color pyrometry set-up for real-time non-contact temperature and emissivity measurement. The system includes a single optical fiber to collect radiation emitted by a target, a reflective rotating chopper to split the collected radiation into two or more paths while modulating the radiation for lock-in amplification (i.e., phase-sensitive detection), at least two detectors possibly of different spectral bandwidths with or without filters to limit the wavelength regions detected and optics to direct and focus the radiation onto the sensitive areas of the detectors. A computer algorithm is used to calculate the true temperature and emissivity of a target based on blackbody calibrations. The system components are enclosed in a light-tight housing, with provision for the fiber to extend outside to collect the radiation. Radiation emitted by the target is transmitted through the fiber to the reflective chopper, which either allows the radiation to pass straight through or reflects the radiation into one or more separate paths. Each path includes a detector with or without filters and corresponding optics to direct and focus the radiation onto the active area of the detector. The signals are recovered using lock-in amplification. Calibration formulas for the signals obtained using a blackbody of known temperature are used to compute the true temperature and emissivity of the target. The temperature range of the pyrometer system is determined by the spectral characteristics of the optical components.

  2. Single-fiber multi-color pyrometry

    DOE Patents [OSTI]

    Small, IV, Ward; Celliers, Peter

    2004-01-27

    This invention is a fiber-based multi-color pyrometry set-up for real-time non-contact temperature and emissivity measurement. The system includes a single optical fiber to collect radiation emitted by a target, a reflective rotating chopper to split the collected radiation into two or more paths while modulating the radiation for lock-in amplification (i.e., phase-sensitive detection), at least two detectors possibly of different spectral bandwidths with or without filters to limit the wavelength regions detected and optics to direct and focus the radiation onto the sensitive areas of the detectors. A computer algorithm is used to calculate the true temperature and emissivity of a target based on blackbody calibrations. The system components are enclosed in a light-tight housing, with provision for the fiber to extend outside to collect the radiation. Radiation emitted by the target is transmitted through the fiber to the reflective chopper, which either allows the radiation to pass straight through or reflects the radiation into one or more separate paths. Each path includes a detector with or without filters and corresponding optics to direct and focus the radiation onto the active area of the detector. The signals are recovered using lock-in amplification. Calibration formulas for the signals obtained using a blackbody of known temperature are used to compute the true temperature and emissivity of the target. The temperature range of the pyrometer system is determined by the spectral characteristics of the optical components.

  3. Atmospheric Radiation Measurement program climate research facility operations quarterly report January 1 - March 31, 2009.

    SciTech Connect (OSTI)

    Sisterson, D. L.

    2009-04-23

    Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real-time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year (FY) dating back to 1998. The U.S. Department of Energy (DOE) requires national user facilities to report time-based operating data. The requirements concern the actual hours of operation (ACTUAL); the estimated maximum operation or uptime goal (OPSMAX), which accounts for planned downtime; and the VARIANCE [1 - (ACTUAL/OPSMAX)], which accounts for unplanned downtime. The OPSMAX time for the second quarter of FY 2009 for the Southern Great Plains (SGP) site is 2,052.00 hours (0.95 x 2,160 hours this quarter). The OPSMAX for the North Slope Alaska (NSA) locale is 1,944.00 hours (0.90 x 2,160), and for the Tropical Western Pacific (TWP) locale is 1,836.00 hours (0.85 x 2,160). The OPSMAX time for the ARM Mobile Facility (AMF) is not reported this quarter because not all of the metadata have been acquired that are used to generate this metric. The differences in OPSMAX performance reflect the complexity of local logistics and the frequency of extreme weather events. It is impractical to measure OPSMAX for each instrument or data stream. Data availability reported here refers to the average of the individual, continuous data streams that have been received by the Archive. Data not at the Archive are caused by downtime (scheduled or unplanned) of the individual instruments. Therefore, data availability

  4. Atmospheric Radiation Measurement program climate research facility operations quarterly report.

    SciTech Connect (OSTI)

    Sisterson, D. L.; Decision and Information Sciences

    2006-09-06

    Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year dating back to 1998. The U.S. Department of Energy requires national user facilities to report time-based operating data. The requirements concern the actual hours of operation (ACTUAL); the estimated maximum operation or uptime goal (OPSMAX), which accounts for planned downtime; and the VARIANCE [1-(ACTUAL/OPSMAX)], which accounts for unplanned downtime. The OPSMAX time for the third quarter for the Southern Great Plains (SGP) site is 2,074.80 hours (0.95 x 2,184 hours this quarter). The OPSMAX for the North Slope Alaska (NSA) locale is 1,965.60 hours (0.90 x 2,184), and that for the Tropical Western Pacific (TWP) locale is 1,856.40 hours (0.85 x 2,184). The OPSMAX time for the ARM Mobile Facility (AMF) is 2,074.80 hours (0.95 x 2,184). The differences in OPSMAX performance reflect the complexity of local logistics and the frequency of extreme weather events. It is impractical to measure OPSMAX for each instrument or data stream. Data availability reported here refers to the average of the individual, continuous data streams that have been received by the Archive. Data not at the Archive are caused by downtime (scheduled or unplanned) of the individual instruments. Therefore, data availability is directly related to individual instrument uptime. Thus, the average percent of data in the Archive

  5. Atmospheric Radiation Measurement program climate research facilities quarterly report April 1 - June 30, 2009.

    SciTech Connect (OSTI)

    Sisterson, D. L.

    2009-07-14

    Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near-real time. Raw and processed data are then sent approximately daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year (FY) dating back to 1998. The U.S. Department of Energy (DOE) requires national user facilities to report time-based operating data. The requirements concern the actual hours of operation (ACTUAL); the estimated maximum operation or uptime goal (OPSMAX), which accounts for planned downtime; and the VARIANCE [1 - (ACTUAL/OPSMAX)], which accounts for unplanned downtime. The OPSMAX time for the third quarter of FY 2009 for the Southern Great Plains (SGP) site is 2,074.80 hours (0.95 x 2,184 hours this quarter); for the North Slope Alaska (NSA) locale it is 1,965.60 hours (0.90 x 2,184); and for the Tropical Western Pacific (TWP) locale it is 1,856.40 hours (0.85 x 2,184). The ARM Mobile Facility (AMF) was officially operational May 1 in Graciosa Island, the Azores, Portugal, so the OPSMAX time this quarter is 1390.80 hours (0.95 x 1464). The differences in OPSMAX performance reflect the complexity of local logistics and the frequency of extreme weather events. It is impractical to measure OPSMAX for each instrument or data stream. Data availability reported here refers to the average of the individual, continuous data streams that have been received by the Archive. Data not at the Archive are caused by downtime (scheduled or unplanned) of the individual instruments. Therefore, data

  6. Atmospheric Radiation Measurement program climate research facility operations quarterly report July 1 - Sep. 30, 2009.

    SciTech Connect (OSTI)

    Sisterson, D. L.

    2009-10-15

    Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near-real time. Raw and processed data are then sent approximately daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year (FY) dating back to 1998. The U.S. Department of Energy (DOE) requires national user facilities to report time-based operating data. The requirements concern the actual hours of operation (ACTUAL); the estimated maximum operation or uptime goal (OPSMAX), which accounts for planned downtime; and the VARIANCE [1 - (ACTUAL/OPSMAX)], which accounts for unplanned downtime. The OPSMAX time for the fourth quarter of FY 2009 for the Southern Great Plains (SGP) site is 2,097.60 hours (0.95 ? 2,208 hours this quarter). The OPSMAX for the North Slope Alaska (NSA) locale is 1,987.20 hours (0.90 ? 2,208) and for the Tropical Western Pacific (TWP) locale is 1,876.8 hours (0.85 ? 2,208). The ARM Mobile Facility (AMF) was officially operational May 1 in Graciosa Island, the Azores, Portugal, so the OPSMAX time this quarter is 2,097.60 hours (0.95 x 2,208). The differences in OPSMAX performance reflect the complexity of local logistics and the frequency of extreme weather events. It is impractical to measure OPSMAX for each instrument or data stream. Data availability reported here refers to the average of the individual, continuous data streams that have been received by the Archive. Data not at the Archive result from downtime (scheduled or unplanned) of the individual instruments. Therefore, data

  7. Atmospheric Radiation Measurement program climate research facility operations quarterly report April 1 - June 30, 2007.

    SciTech Connect (OSTI)

    Sisterson, D. L.

    2007-07-26

    Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year (FY) dating back to 1998. The U.S. Department of Energy requires national user facilities to report time-based operating data. The requirements concern the actual hours of operation (ACTUAL); the estimated maximum operation or uptime goal (OPSMAX), which accounts for planned downtime; and the VARIANCE [1 - (ACTUAL/OPSMAX)], which accounts for unplanned downtime. The OPSMAX time for the third quarter of FY 2007 for the Southern Great Plains (SGP) site is 2,074.8 hours (0.95 x 2,184 hours this quarter). The OPSMAX for the North Slope Alaska (NSA) locale is 1,965.6 hours (0.90 x 2,184), and that for the Tropical Western Pacific (TWP) locale is 1,856.4 hours (0.85 x 2,184). The OPSMAX time for the ARM Mobile Facility (AMF) is 2,074.8 hours (0.95 x 2,184). The differences in OPSMAX performance reflect the complexity of local logistics and the frequency of extreme weather events. It is impractical to measure OPSMAX for each instrument or data stream. Data availability reported here refers to the average of the individual, continuous data streams that have been received by the Archive. Data not at the Archive are caused by downtime (scheduled or unplanned) of the individual instruments. Therefore, data availability is directly related to individual instrument uptime. Thus, the average percent of data in

  8. The Low-Level Jet over the Southern Great Plains Determined from Observations and Reanalyses and Its Impact on Moisture Transport

    SciTech Connect (OSTI)

    Berg, Larry K.; Riihimaki, Laura D.; Qian, Yun; Yan, Huiping; Huang, Maoyi

    2015-09-01

    This study utilizes five commonly used reanalysis products, including the NCEP-DOE Reanalysis 2 (NCEP2), ECMWF Re-Analysis (ERA)-Interim, Japanese 25-year Reanalysis (JRA-25), Modern-Era Retrospective Analysis for Research and Applications (MERRA), and North American Regional Reanalysis (NARR) to evaluate features of the Southern Great Plains Low Level Jet (LLJ) above the Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) Southern Great Plains site. Two sets of radiosonde data are utilized: the six-week Midlatitude Continental Convective Clouds Experiment (MC3E), and a ten-year period spanning 2001-2010. All five reanalysis are compared to MC3E data, while only the NARR and MERRA are compared to the ten-year data. Each reanalysis is able to represent most aspects of the composite LLJ profile, although there is a tendency for each reanalysis to overestimate the wind speed between the nose of the LLJ and 700 mb. There are large discrepancies in the number of LLJ observed and derived from the reanalysis, particularly for strong LLJs that leads to an underestimate of the water vapor transport associated with LLJs. When the ten-year period is considered, the NARR overestimates and MERRA underestimates the total moisture transport, but both underestimate the transport associated with strong LLJs by factors of 2.0 and 2.7 for the NARR and MERR, respectively. During MC3E there were differences in the patterns of moisture convergence and divergence, with the MERRA having an area of moisture divergence over Oklahoma, while the NARR has moisture convergence. The patterns of moisture convergence and divergence are more consistent during the ten-year period.

  9. A broadband X-ray study of the Geminga pulsar with NuSTAR And XMM-Newton

    SciTech Connect (OSTI)

    Mori, Kaya; Gotthelf, Eric V.; Halpern, Jules P.; Beloborodov, Andrei M.; Hailey, Charles J.; Dufour, Francois; Kaspi, Victoria M.; An, Hongjun; Bachetti, Matteo; Boggs, Steven E.; Craig, William W.; Christensen, Finn E.; Harrison, Fiona A.; Kouveliotou, Chryssa; Pivovaroff, Michael J.; Stern, Daniel; Zhang, William W.

    2014-10-01

    We report on the first hard X-ray detection of the Geminga pulsar above 10 keV using a 150 ks observation with the Nuclear Spectroscopic Telescope Array (NuSTAR) observatory. The double-peaked pulse profile of non-thermal emission seen in the soft X-ray band persists at higher energies. Broadband phase-integrated spectra over the 0.2-20 keV band with NuSTAR and archival XMM-Newton data do not fit to a conventional two-component model of a blackbody plus power law, but instead exhibit spectral hardening above ∼5 keV. We find that two spectral models fit the data well: (1) a blackbody (kT {sub 1} ∼ 42 eV) with a broken power law (Γ{sub 1} ∼ 2.0, Γ{sub 2} ∼ 1.4 and E {sub break} ∼ 3.4 keV) and (2) two blackbody components (kT {sub 1} ∼ 44 eV and kT {sub 2} ∼ 195 eV) with a power-law component (Γ ∼ 1.7). In both cases, the extrapolation of the Rayleigh-Jeans tail of the thermal component is consistent with the UV data, while the non-thermal component overpredicts the near-infrared data, requiring a spectral flattening at E ∼ 0.05-0.5 keV. While strong phase variation of the power-law index is present below ∼5 keV, our phase-resolved spectroscopy with NuSTAR indicates that another hard non-thermal component with Γ ∼ 1.3 emerges above ∼5 keV. The spectral hardening in non-thermal X-ray emission as well as spectral flattening between the optical and X-ray bands argue against the conjecture that a single power law may account for multi-wavelength non-thermal spectra of middle-aged pulsars.

  10. Scientific results from the cosmic background explorer (COBE). [Information on cosmic radiation

    SciTech Connect (OSTI)

    Bennett, C.L.; Boggess, N.W.; Cheng, E.S.; Hauser, M.G.; Kelsall, T.; Mather, J.C.; Moseley, S.H. Jr.; Shafer, R.A.; Silverberg, R.F. ); Murdock, T.L. ); Smoot, G.F. ); Weiss, R. ); Wright, E.L. )

    1993-06-01

    The National Aeronautics and Space Administration (NASA) has flown the COBE satellite to observe the Big Bang and the subsequent formation of galaxies and large-scale structure. Data from the Far-Infrared Absolute Spectrophotometer (FIRAS) show that the spectrum of the cosmic microwave background is that of a black body of temperature T = 2.73 [+-] 0.06 K, with no deviation from a black-body spectrum greater than 0.25% of the peak brightness. The data from the Differential Microwave Radiometers (DMR) show statistically significant cosmic microwave background anisotropy, consistent with a scale-invariant primordial density fluctuation spectrum. Measurements from the Diffuse Infrared Background Experiment (DIRBE) provide new conservation upper limits to the cosmic infrared background. Extensive modeling of solar system and galactic infrared foregrounds is required for further improvement in the cosmic infrared background limits. 104 refs., 1 tab.

  11. Equivalence of optical and electrical noise equivalent power of hybrid NbTiN-Al microwave kinetic inductance detectors

    SciTech Connect (OSTI)

    Janssen, R. M. J.; Endo, A.; Visser, P. J. de; Klapwijk, T. M.; Baselmans, J. J. A.

    2014-11-10

    We have measured and compared the response of hybrid NbTiN-Al Microwave Kinetic Inductance Detectors (MKIDs) to changes in bath temperature and illumination by sub-mm radiation. We show that these two stimulants have an equivalent effect on the resonance feature of hybrid MKIDs. We determine an electrical noise equivalent power (NEP) from the measured temperature responsivity, quasiparticle recombination time, superconducting transition temperature, and noise spectrum, all of which can be measured in a dark environment. For the two hybrid NbTiN-Al MKIDs studied in detail, the electrical NEP is within a factor of two of the optical NEP, which is measured directly using a blackbody source.

  12. Measurement of the large-scale anisotropy of the cosmic background radiation at 3mm

    SciTech Connect (OSTI)

    Epstein, G.L.

    1983-12-01

    A balloon-borne differential radiometer has measured the large-scale anisotropy of the cosmic background radiation (CBR) with high sensitivity. The antenna temperature dipole anistropy at 90 GHz (3 mm wavelength) is 2.82 +- 0.19 mK, corresponding to a thermodynamic anistropy of 3.48 +- mK for a 2.7 K blackbody CBR. The dipole direction, 11.3 +- 0.1 hours right ascension and -5.7/sup 0/ +- 1.8/sup 0/ declination, agrees well with measurements at other frequencies. Calibration error dominates magnitude uncertainty, with statistical errors on dipole terms being under 0.1 mK. No significant quadrupole power is found, placing a 90% confidence-level upper limit of 0.27 mK on the RMS thermodynamic quadrupolar anistropy. 22 figures, 17 tables.

  13. Photon-noise limited sensitivity in titanium nitride kinetic inductance detectors

    SciTech Connect (OSTI)

    Hubmayr, J. Beall, J.; Becker, D.; Cho, H.-M.; Hilton, G. C.; Li, D.; Pappas, D. P.; Van Lanen, J.; Vissers, M. R.; Gao, J.; Devlin, M.; Dober, B.; Groppi, C.; Mauskopf, P.; Irwin, K. D.; Wang, Y.; Wei, L. F.

    2015-02-16

    We demonstrate photon-noise limited performance at sub-millimeter wavelengths in feedhorn-coupled, microwave kinetic inductance detectors made of a TiN/Ti/TiN trilayer superconducting film, tuned to have a transition temperature of 1.4 K. Micro-machining of the silicon-on-insulator wafer backside creates a quarter-wavelength backshort optimized for efficient coupling at 250 μm. Using frequency read out and when viewing a variable temperature blackbody source, we measure device noise consistent with photon noise when the incident optical power is >0.5 pW, corresponding to noise equivalent powers >3×10{sup −17} W/√(Hz). This sensitivity makes these devices suitable for broadband photometric applications at these wavelengths.

  14. Spectral Resolution for Five-Element, Filtered, X-Ray Detector (XRD) Arrays Using the Methods of Backus and Gilbert

    SciTech Connect (OSTI)

    FEHL,DAVID LEE; BIGGS,F.; CHANDLER,GORDON A.; STYGAR,WILLIAM A.

    2000-01-17

    The generalized method of Backus and Gilbert (BG) is described and applied to the inverse problem of obtaining spectra from a 5-channel, filtered array of x-ray detectors (XRD's). This diagnostic is routinely fielded on the Z facility at Sandia National Laboratories to study soft x-ray photons ({le}2300 eV), emitted by high density Z-pinch plasmas. The BG method defines spectral resolution limits on the system of response functions that are in good agreement with the unfold method currently in use. The resolution so defined is independent of the source spectrum. For noise-free, simulated data the BG approximating function is also in reasonable agreement with the source spectrum (150 eV black-body) and the unfold. This function may be used as an initial trial function for iterative methods or a regularization model.

  15. The Big Bang, COBE, and the Relic Radiation of Creation (LBNL Science at the Theater)

    ScienceCinema (OSTI)

    Smoot, George

    2011-04-28

    Berkeley Lab's George Smoot won the 2006 Physics Nobel Prize, together with John Mather of NASA Goddard Space Flight Center, for "the discovery of the blackbody form and anisotropy of the cosmic microwave background radiation." The anisotropy showed as small variations in the map of the early universe. This research looks back into the infant universe and provides a better understanding of the origin of galaxies and stars. The cosmic background radiation is a tool to understand the structure and history of the universe and the structure of space-time. These observations have provided increased support for the big bang theory of the universe's origin. The Cosmic Background Explorer (COBE) NASA satellite, launched in 1989, carries instruments that measured various aspects of cosmic microwave background radiation, and produced the data for these compelling scientific results, which opened up a field that continues very actively today.

  16. Cosmological and astrophysical constraints on superconducting cosmic strings

    SciTech Connect (OSTI)

    Miyamoto, Koichi; Nakayama, Kazunori E-mail: kazunori@hep-th.phys.s.u-tokyo.ac.jp

    2013-07-01

    We investigate the cosmological and astrophysical constraints on superconducting cosmic strings (SCSs). SCS loops emit strong bursts of electromagnetic waves, which might affect various cosmological and astrophysical observations. We take into account the effect on the CMB anisotropy, CMB blackbody spectrum, BBN, observational implications on radio wave burst and X-ray or ?-ray events, and stochastic gravitational wave background measured by pulsar timing experiments. We then derive constraints on the parameters of SCS from current observations and estimate prospects for detecting SCS signatures in on-going observations. As a result, we find that these constraints exclude broad parameter regions, and also that on-going radio wave observations can probe large parameter space.

  17. Subkilohertz absolute-frequency measurement of the 467-nm electric octupole transition in {sup 171}Yb{sup +}

    SciTech Connect (OSTI)

    Blythe, P.J.; Gill, P.; Webster, S.A.; Margolis, H.S.; Lea, S.N.; Huang, G.; Choi, S.-K.; Rowley, W.R.C.; Windeler, R.S.

    2003-02-01

    The {sup 2}S{sub 1/2}(F=0){yields}{sup 2}F{sub 7/2}(F=3,m{sub F}=0) transition at 467 nm in a single trapped, laser-cooled ion of {sup 171}Yb{sup +} has been measured to be f{sub Yb{sup +}}=642 121 496 771.26(23) kHz using a femtosecond laser frequency comb generator. The measurement is limited by measurement statistics and by the ac Stark shift, both related to the 4.5 kHz linewidth of the probe laser at the time. The systematic shifts of the transition, including ac Stark, second-order Zeeman, quadrupole, and blackbody shifts, have been evaluated.

  18. A Flat Universe from High-Resolution Maps of the Cosmic MicrowaveBackground Radiation

    SciTech Connect (OSTI)

    de Bernardis, P.; Ade, P.A.R.; Bock, J.J.; Bond, J.R.; Borrill,J.; Boscaleri, A.; Coble, K.; Crill, B.P.; De Gasperis, G.; Farese, P.C.; Ferreira, P.G.; Ganga, K.; Giacometti, M.; Hivon, E.; Hristov, V.V.; Iacoangeli, A.; Jaffe, A.H.; Lange, A.E.; Martinis, L.; Masi, S.; Mason,P.; Mauskopf, P.D.; Melchiorri, A.; Miglio, L.; Montroy, T.; Netterfield,C.B.; Pascale, E.; Piacentini, F.; Pogosyan, D.; Prunet, S.; Rao, S.; Romeo, G.; Ruhl, J.E.; Scaramuzzi, F.; Sforna, D.; Vittorio, N.

    2000-04-28

    The blackbody radiation left over from the Big Bang has been transformed by the expansion of the Universe into the nearly isotropic 2.73 K Cosmic Microwave Background. Tiny inhomogeneities in the early Universe left their imprint on the microwave background in the form of small anisotropies in its temperature. These anisotropies contain information about basic cosmological parameters, particularly the total energy density and curvature of the universe. Here we report the first images of resolved structure in the microwave background anisotropies over a significant part of the sky. Maps at four frequencies clearly distinguish the microwave background from foreground emission. We compute the angular power spectrum of the microwave background, and find a peak at Legendre multipole {ell}{sub peak} = (197 {+-} 6), with an amplitude DT{sub 200} = (69 {+-} 8){mu}K. This is consistent with that expected for cold dark matter models in a flat (euclidean) Universe, as favored by standard inflationary scenarios.

  19. A comparison of irradiance responsivity and thermodynamic temperature measurement between PTB and NIM

    SciTech Connect (OSTI)

    Lu, X.; Yuan, Z.; Anhalt, K.; Taubert, R. D.

    2013-09-11

    This paper describes a comparison between PTB and NIM in the field of absolute spectral-band radiometry and thermodynamic temperature measurement. For the comparison a NIM made interference filter radiometer with a centre wavelength of 633 nm was taken to PTB. The filter radiometer was calibrated at NIM and PTB with respect to spectral irradiance responsivity. For the integral value in the band-pass range an agreement of 0.1% was observed in both calibrations. In a next step, the 633 nm filter radiometer was used to measure the temperature of a high-temperature blackbody in comparison to an 800 nm filter radiometer of PTB in the temperature range between 1400 K and 2750 K. The thermodynamic temperature measured by the two filter radiometers agreed to within 0.2 K to 0.5 K with an estimated measurement uncertainty ranging between 0.1 K and 0.4 K (k=1)

  20. High detectivity short-wavelength II-VI quantum cascade detector

    SciTech Connect (OSTI)

    Ravikumar, Arvind P. Gmachl, Claire F.; Garcia, Thor A.; Tamargo, Maria C.; Jesus, Joel De

    2014-08-11

    We report on the experimental demonstration of a ZnCdSe/ZnCdMgSe-based short-wavelength photovoltaic Quantum Cascade Detector (QCD). The QCD operates in two spectral bands centered around 2.6??m and 3.6??m. Calibrated blackbody measurements yield a peak responsivity of 0.1?mA/W or 2400?V/W at 80?K, and a corresponding 300?K background radiation limited infrared performance detectivity (BLIP) of ?2.5??10{sup 10?}cm ?Hz/W. Comparison of background illuminated and dark current-voltage measurements demonstrates a BLIP temperature of 200?K. The device differential resistance-area product, decreases from about 10{sup 6} ? cm{sup 2} at 80?K to about 8000 ? cm{sup 2} at 300?K, indicative of the ultra-low Johnson noise in the detectors.

  1. Horn-coupled, commercially-fabricated aluminum lumped-element kinetic inductance detectors for millimeter wavelengths

    SciTech Connect (OSTI)

    McCarrick, H. Flanigan, D.; Jones, G.; Johnson, B. R.; Araujo, D.; Limon, M.; Luu, V.; Miller, A.; Ade, P.; Doyle, S.; Tucker, C.; Bradford, K.; Che, G.; Cantor, R.; Day, P.; Leduc, H.; Mauskopf, P.; Mroczkowski, T.; Zmuidzinas, J.

    2014-12-15

    We discuss the design, fabrication, and testing of prototype horn-coupled, lumped-element kinetic inductance detectors (LEKIDs) designed for cosmic microwave background studies. The LEKIDs are made from a thin aluminum film deposited on a silicon wafer and patterned using standard photolithographic techniques at STAR Cryoelectronics, a commercial device foundry. We fabricated 20-element arrays, optimized for a spectral band centered on 150 GHz, to test the sensitivity and yield of the devices as well as the multiplexing scheme. We characterized the detectors in two configurations. First, the detectors were tested in a dark environment with the horn apertures covered, and second, the horn apertures were pointed towards a beam-filling cryogenic blackbody load. These tests show that the multiplexing scheme is robust and scalable, the yield across multiple LEKID arrays is 91%, and the measured noise-equivalent temperatures for a 4 K optical load are in the range 266 ?K?(s)

  2. Diode laser satellite systems for beamed power transmission

    SciTech Connect (OSTI)

    Williams, M.D.; Kwon, J.H.; Walker, G.H.; Humes, D.H.

    1990-01-01

    A power system composed of an orbiting laser satellite and a surface-based receiver/converter is described. Power is transmitted from the satellite to the receiver/converter by laser beam. The satellite components are: (1) solar collector; (2) blackbody; (3) photovoltaic cells; (4) heat radiators; (5) laser system; and (6) transmission optics. The receiver/converter components are: receiver dish; lenticular lens; photocells; and heat radiator. Although the system can be adapted to missions at many locations in the solar system, only two are examined here: powering a lunar habitat; and powering a lunar rover. Power system components are described and their masses, dimensions, operating powers, and temperatures, are estimated using known or feasible component capabilities. The critical technologies involved are discussed and other potential missions are mentioned.

  3. Monochromatic x-ray imaging experiments on the Sandia National Laboratories Z facility (invited)

    SciTech Connect (OSTI)

    Sinars, D.B.; Bennett, G.R.; Wenger, D.F.; Cuneo, M.E.; Hanson, D.L.; Porter, J.L.; Adams, R.G.; Rambo, P.K.; Rovang, D.C.; Smith, I.C.

    2004-10-01

    The Z facility is a 20 MA, 100 ns rise time, pulsed power driver for z-pinch plasma radiation sources. The Z facility can make >200 TW, 1-2 MJ, near-blackbody radiation sources through the compression of cylindrical wire arrays. These sources are being used as drivers to study inertial-confinement fusion capsule implosions, complex radiation-hydrodynamic jet experiments, and wire-array z-pinch physics tests. To backlight plasmas in this environment we have built diagnostics based on spherically bent crystals that provide high spatial resolution (9-10 {mu}m), a narrow spectral bandpass (<0.5 eV), and a large field of view (4 mmx20 mm). These diagnostics use the 2 TW, multi-kJ Z-Beamlet laser to produce x-ray emission sources at 1.865 or 6.151 keV for backlighting.

  4. New measurements of the spectrum of the cosmic microwave background

    SciTech Connect (OSTI)

    Peterson, J.B.; Richards, P.L.; Bonomo, J.L.; Timusk, T.

    1984-06-01

    Accurate measurements of the spectrum of the cosmic microwave background (CMB) can provide useful tests of cosmological theories. The data set existing in 1982 has been summarized on a number of occasions and is shown. To first approximation the CMB is characterized by a single temperature and thus has a blackbody spectrum over the frequency range from 0.02 to 24 cm/sup -1/. The error limits given for these experiments are dominated by systematic errors and are often very subjective. Consequently, it is not clear how to analyze the data set in a valid way. The general impression, however, is of a scatter in the high frequency data that is somewhat larger than would be expected from the given error limits. We have designed a new apparatus to measure the spectrum of the CMB in the frequency range from 3 to 10 cm/sup -1/. 13 references, 5 figures.

  5. DISCOVERY OF A COMPACT COMPANION TO THE HOT SUBDWARF STAR BD +37 Degree-Sign 442

    SciTech Connect (OSTI)

    La Palombara, Nicola; Mereghetti, Sandro; Tiengo, Andrea; Esposito, Paolo E-mail: sandro@iasf-milano.inaf.it E-mail: paoloesp@oa-cagliari.inaf.it

    2012-05-10

    We report the results of the first X-ray observation of the luminous and helium-rich O-type subdwarf BD +37 Degree-Sign 442 carried out with the XMM-Newton satellite in 2011 August. X-ray emission is detected with a flux of about 3 Multiplication-Sign 10{sup -14} erg cm{sup -2} s{sup -1} (0.2-1 keV) and a very soft spectrum, well fit by the sum of a blackbody with temperature kT{sub BB} = 45{sup +11}{sub -9} eV, and a power law with a poorly constrained photon index. Significant pulsations with a period of 19.2 s are detected, indicating that the X-ray emission originates in a white dwarf or neutron star companion, most likely powered by accretion from the wind of BD +37 Degree-Sign 442.

  6. Fine Structure of Dark Energy and New Physics

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

    Jejjala, Vishnu; Kavic, Michael; Minic, Djordje

    2007-01-01

    Following our recent work on the cosmological constant problem, in this letter we make a specific proposal regarding the fine structure (i.e., the spectrum) of dark energy. The proposal is motivated by a deep analogy between the blackbody radiation problem, which led to the development of quantum theory, and the cosmological constant problem, for which we have recently argued calls for a conceptual extension of the quantum theory. We argue that the fine structure of dark energy is governed by a Wien distribution, indicating its dual quantum and classical nature. We discuss observational consequences of such a picture of darkmore » energy and constrain the distribution function.« less

  7. Doppler-Free Spectroscopy of the {sup 1}S{sub 0}-{sup 3}P{sub 0} Optical Clock Transition in Laser-Cooled Fermionic Isotopes of Neutral Mercury

    SciTech Connect (OSTI)

    Petersen, M.; Chicireanu, R.; Dawkins, S. T.; Magalhaes, D. V.; Mandache, C.; Le Coq, Y.; Clairon, A.; Bize, S.

    2008-10-31

    We report direct laser spectroscopy of the {sup 1}S{sub 0}-{sup 3}P{sub 0} transition at 265.6 nm in fermionic isotopes of neutral mercury in a magneto-optical trap. Measurements of the frequency against the LNE-SYRTE primary reference using an optical frequency comb yield 1 128 575 290 808.4{+-}5.6 kHz in {sup 199}Hg and 1 128 569 561 139.6{+-}5.3 kHz in {sup 201}Hg. The uncertainty, allowed by the observation of the Doppler-free recoil doublet, is 4 orders of magnitude lower than previous indirect determinations. Mercury is a promising candidate for future optical lattice clocks due to its low sensitivity to blackbody radiation.

  8. Polarizabilities of the beryllium clock transition

    SciTech Connect (OSTI)

    Mitroy, J.

    2010-11-15

    The polarizabilities of the three lowest states of the beryllium atom are determined from a large basis configuration interaction calculation. The polarizabilities of the 2s{sup 2} {sup 1}S{sup e} ground state (37.73a{sub 0}{sup 3}) and the 2s2p {sup 3}P{sub 0}{sup o} metastable state (39.04a{sub 0}{sup 3}) are found to be very similar in size and magnitude. This leads to an anomalously small blackbody radiation shift at 300 K of -0.018(4) Hz for the 2s{sup 2} {sup 1}S{sup e}-2s2p {sup 3}P{sub 0}{sup o} clock transition. Magic wavelengths for simultaneous trapping of the ground and metastable states are also computed.

  9. Relativistic general-order coupled-cluster method for high-precision calculations: Application to the Al{sup +} atomic clock

    SciTech Connect (OSTI)

    Kallay, Mihaly; Nataraj, H. S.; Sahoo, B. K.; Das, B. P.; Visscher, Lucas

    2011-03-15

    We report the implementation of a general-order relativistic coupled-cluster method for performing high-precision calculations of atomic and molecular properties. As a first application, the black-body radiation shift of the Al{sup +} clock has been estimated precisely. The computed shift relative to the frequency of the 3s{sup 2} {sup 1}S{sub 0}{sup e}{yields}3s3p {sup 3}P{sub 0}{sup o} clock transition given by (-3.66{+-}0.60)x10{sup -18} calls for an improvement over the recent measurement with a reported result of (-9{+-}3)x10{sup -18}[Phys. Rev. Lett. 104, 070802 (2010)].

  10. Ab initio calculations of external-field shifts of the 661-nm quadrupolar clock transition in neutral Ag atoms

    SciTech Connect (OSTI)

    Topcu, Suat; Nasser, Jamil; Daku, Latevi Max Lawson; Fritzsche, Stephan

    2006-04-15

    Frequency shifts of the Ag I 4d{sup 10}5s {sup 2}S{sub 1/2}(F=0,M{sub F}=0) to 4d{sup 9}5s{sup 2} {sup 2}D{sub 5/2}(F{sup '}=2,M{sub F{sup '}}=0) electric-quadrupole transition at 330.6 nm due to external fields are calculated using multiconfigurational self-consistent field methods. As this forbidden transition is free from first order Doppler and Zeeman effects, it is under investigation for the realization of an atomic optical clock. The calculated perturbations are the light shift, the blackbody frequency shift, and the quadratic Zeeman shift. Results show that a total uncertainty of 10{sup -18} could be reach without confining the atoms in a Lamb-Dicke regime in an optical lattice.

  11. A soft x-ray transmission grating imaging-spectrometer for the National Ignition Facility

    SciTech Connect (OSTI)

    Moore, A S; Guymer, T M; Kline, J L; Morton, J; Taccetti, M; Lanier, N E; Bentley, C; Workman, J; Peterson, B; Mussack, K; Cowan, J; Prasad, R; Richardson, M; Burns, S; Kalantar, D H; Benedetti, L R; Bell, P; Bradley, D; Hsing, W; Stevenson, M

    2012-05-01

    A soft x-ray transmission grating spectrometer has been designed for use on high energy-density physics experiments at the National Ignition Facility (NIF); coupled to one of the NIF gated x-ray detectors (GXD) it records sixteen time-gated spectra between 250 and 1000eV with 100ps temporal resolution. The trade-off between spectral and spatial resolution leads to an optimized design for measurement of emission around the peak of a 100-300eV blackbody spectrum. Performance qualification results from the NIF, the Trident Laser Facility and VUV beamline at the National Synchrotron Light Source (NSLS), evidence a <100{micro}m spatial resolution in combination with a source-size limited spectral resolution that is <10eV at photon energies of 300eV.

  12. Apparatus for accurately measuring high temperatures

    DOE Patents [OSTI]

    Smith, D.D.

    The present invention is a thermometer used for measuring furnace temperatures in the range of about 1800/sup 0/ to 2700/sup 0/C. The thermometer comprises a broadband multicolor thermal radiation sensor positioned to be in optical alignment with the end of a blackbody sight tube extending into the furnace. A valve-shutter arrangement is positioned between the radiation sensor and the sight tube and a chamber for containing a charge of high pressure gas is positioned between the valve-shutter arrangement and the radiation sensor. A momentary opening of the valve shutter arrangement allows a pulse of the high gas to purge the sight tube of air-borne thermal radiation contaminants which permits the radiation sensor to accurately measure the thermal radiation emanating from the end of the sight tube.

  13. Apparatus for accurately measuring high temperatures

    DOE Patents [OSTI]

    Smith, Douglas D.

    1985-01-01

    The present invention is a thermometer used for measuring furnace temperaes in the range of about 1800.degree. to 2700.degree. C. The thermometer comprises a broadband multicolor thermal radiation sensor positioned to be in optical alignment with the end of a blackbody sight tube extending into the furnace. A valve-shutter arrangement is positioned between the radiation sensor and the sight tube and a chamber for containing a charge of high pressure gas is positioned between the valve-shutter arrangement and the radiation sensor. A momentary opening of the valve shutter arrangement allows a pulse of the high gas to purge the sight tube of air-borne thermal radiation contaminants which permits the radiation sensor to accurately measure the thermal radiation emanating from the end of the sight tube.

  14. The Vela pulsar with an active fallback disk

    SciTech Connect (OSTI)

    zskan, Gke; Ek?i, K. Yavuz [Faculty of Science and Letters, Department of Physics, ?stanbul Technical University, Maslak 34469, ?stanbul (Turkey); Hambaryan, Valeri; Neuhuser, Ralph; Hohle, Markus M.; Ginski, Christian [Astrophysikalisches Institut und Universitts-Sternwarte, Universitt Jena, Schillergchen 2-3, 07745 Jena (Germany); Werner, Klaus, E-mail: eksi@itu.edu.tr [Institute for Astronomy and Astrophysics, Kepler Center for Astro and Particle Physics, Eberhard Karls University, Sand 1, D-72076 Tbingen (Germany)

    2014-11-20

    Fallback disks are expected to form around young neutron stars. The presence of these disks can be revealed by their blackbody spectrum in the infrared, optical, and UV bands. We present a re-reduction of the archival optical and infrared data of the Vela pulsar, together with the existing infrared and UV spectrum of Vela, and model their unpulsed components with the blackbody spectrum of a supernova debris disk. We invoke the quiescent disk solution of Sunyaev and Shakura for the description of the disk in the propeller stage and find the inner radius of the disk to be inside the light cylinder radius. We perform a high-resolution X-ray analysis with XMM-Newton and find a narrow absorption feature at 0.57 keV that can be interpreted as the K {sub ?} line of He-like oxygen (O VII). The strength of the line indicates an element over-abundance in our line of sight exceeding the amounts that would be expected from interstellar medium. The spectral feature may originate from the pulsar wind nebula and may be partly caused by the reprocessed X-ray radiation by the fallback disk. We discuss the lower-than-three braking index of Vela as partially due to the contribution of the propeller torques. Our results suggest that the pulsar mechanism can work simultaneously with the propeller processes and that the debris disks can survive the radiation pressure for at least ?10{sup 4} yr. As Vela is a relatively close object, and a prototypical pulsar, the presence of a disk, if confirmed, may indicate the ubiquity of debris disks around young neutron stars.

  15. Science Overview Document Indirect and Semi-Direct Aerosol Campaign (ISDAC) April 2008

    SciTech Connect (OSTI)

    SJ Ghan; B Schmid; JM Hubbe; CJ Flynn; A Laskin; AA Zelenyuk; DJ Czizco; CN Long; G McFarquhar; J Verlinde; J Harrington; JW Strapp; P Liu; A Korolev; A McDonald; M Wolde; A Fridlind; T Garrett; G Mace; G Kok; S Brooks; D Collins; D Lubin; P Lawson; M Dubey; C Mazzoleni; M Shupe; S Xie; DD Turner; Q Min; EJ Mlawer; D Mitchell

    2007-11-01

    The ARM Climate Research Facility’s (ACRF) Aerial Vehicle Program (AVP) will deploy an intensive cloud and aerosol observing system to the ARM North Slope of Alaska (NSA) locale for a five week Indirect and Semi-Direct Aerosol Campaign (ISDAC) during period 29 March through 30 April 2008. The deployment period is within the International Polar Year, thus contributing to and benefiting from the many ancillary observing systems collecting data synergistically. We will deploy the Canadian National Research Council Convair 580 aircraft to measure temperature, humidity, total particle number, aerosol size distribution, single particle composition, concentrations of cloud condensation nuclei and ice nuclei, optical scattering and absorption, updraft velocity, cloud liquid water and ice contents, cloud droplet and crystal size distributions, cloud particle shape, and cloud extinction. In addition to these aircraft measurements, ISDAC will deploy two instruments at the ARM site in Barrow: a spectroradiometer to retrieve cloud optical depth and effective radius, and a tandem differential mobility analyzer to measure the aerosol size distribution and hygroscopicity. By using many of the same instruments used during Mixed-Phase Arctic Cloud Experiment (M-PACE), conducted in October 2004, we will be able to contrast the arctic aerosol and cloud properties during the fall and spring transitions. The aerosol measurements can be used in cloud models driven by objectively analyzed boundary conditions to test whether the cloud models can simulate the aerosol influence on the clouds. The influence of aerosol and boundary conditions on the simulated clouds can be separated by running the cloud models with all four combinations of M-PACE and ISDAC aerosol and boundary conditions: M-PACE aerosol and boundary conditions, M-PACE aerosol and ISDAC boundary conditions, ISDAC aerosol and M-PACE boundary conditions, and ISDAC aerosol and boundary conditions. ISDAC and M-PACE boundary

  16. Integrated assessment of global warming

    SciTech Connect (OSTI)

    Ott, K.O.

    1996-12-31

    The anomalies of sea surface temperatures, which show a warming trend since the 1850s through the decade 1960/70 of {Delta}SST {approximately} 0.3 C, are complemented by changes of the ground surface temperature ({Delta}GST). The global surface temperature change, based on these data, allows an integrated assessment of the associated increase in black-body irradiance and a comparison with the enhanced greenhouse-gas back-scattering. Information on the GST history is obtained from unfolding analyses of underground temperature distributions measured in 90 boreholes in Alaskan permafrost and Canadian bedrock. These analyses show GST increases ({Delta}GST) since the 19th century through 1960/70 of 3 C on average, with standard deviations of +1.8 C and {minus}0.9 C on the high and low end respectively. The onset of the warming trend, which is uncertain in the GST data, is timed more accurately by detailed length records of large valley glaciers in the US and the Alps. Evaluation of the heat capacities and heat transfer indicates that the temperature response to an increase in radiative forcing must be much larger on land than on the sea. Conversely, the observed large ratio of {Delta}GST and {Delta}SST can only be explained by increased radiative forcing. From 1960/70 through the warmest decade on record, 1980/90, global {Delta}SST and {Delta}SAT have further increased to 0.6 C and 0.8 C respectively, But, the most recent GST data are not accurate enough to extend the comparison through 1990. Calculation of the increase of radiative forcing from back-scattering of greenhouse gases for 1850 to 1970 yields 1.3 W/cm{sup 2}. The increase in black-body irradiance from 3.6 C warming on land and 0.3 C on sea provides the required balance. The warming on land of 3.6 C is larger than the average value of 3.0 C, but well within the observed range.

  17. TIDAL DISRUPTION FLARES: THE ACCRETION DISK PHASE

    SciTech Connect (OSTI)

    Montesinos Armijo, Matias; De Freitas Pacheco, Jose A. [Observatoire de la Cote d'Azur, Laboratoire Cassiopee, Universite de Nice Sophia-Antipolis Bd de l'Observatoire, BP 4229, 06304 Nice Cedex 4 (France)

    2011-08-01

    The evolution of an accretion disk, formed as a consequence of the disruption of a star by a black hole, is followed by solving numerically hydrodynamic equations. The present investigation aims to study the dependence of resulting light curves on dynamical and physical properties of such a transient disk during its existence. One of the main results derived from our simulations is that blackbody fits of X-ray data tend to overestimate the true mean disk temperature. In fact, the temperature derived from blackbody fits should be identified with the color X-ray temperature rather than the average value derived from the true temperature distribution along the disk. The time interval between the beginning of the circularization of the bound debris and the beginning of the accretion process by the black hole is determined by the viscous (or accretion) timescale, which also fixes the rising part of the resulting light curve. The luminosity peak coincides with the beginning of matter accretion by the black hole and the late evolution of the light curve depends on the evolution of the debris fallback rate. Peak bolometric luminosities are in the range 10{sup 45}-10{sup 46} erg s{sup -1}, whereas peak luminosities in soft X-rays (0.2-2.0 keV) are typically one order of magnitude lower. The typical timescale derived from our preferred models for the flare luminosity to decay by two orders of magnitude is about 3-4 yr. Predicted soft X-ray light curves reproduce quite well data on galaxies in which a variable X-ray emission possibly related to a tidal event was detected. In the cases of NGC 3599 and IC 3599, data are reproduced well by models defined by a black hole with mass {approx}10{sup 7} M{sub sun} and a disrupted star of about 1 solar mass. The X-ray variation observed in XMMSL1 is consistent with a model defined by a black hole with mass {approx}3 x 10{sup 6} M{sub sun} and a disrupted star of 1 solar mass, while that observed in the galaxy situated in the cluster A

  18. New Measurement of the Electron Magnetic Moment and the Fine Structure Constant: A First Application of a One-Electron Quantum Cyclotron

    ScienceCinema (OSTI)

    Gabrielse, Gerald [Harvard University, Cambridge, Massachusetts, United States

    2009-09-01

    Remarkably, the famous UW measurement of the electron magnetic moment has stood since 1987. With QED theory, this measurement has determined the accepted value of the fine structure constant. This colloquium is about a new Harvard measurement of these fundamental constants. The new measurement has an uncertainty that is about six times smaller, and it shifts the values by 1.7 standard deviations. One electron suspended in a Penning trap is used for the new measurement, like in the old measurement. What is different is that the lowest quantum levels of the spin and cyclotron motion are resolved, and the cyclotron as well as spin frequencies are determined using quantum jump spectroscopy. In addition, a 0.1 mK Penning trap that is also a cylindrical microwave cavity is used to control the radiation field, to suppress spontaneous emission by more than a factor of 100, to control cavity shifts, and to eliminate the blackbody photons that otherwise stimulate excitations from the cyclotron ground state. Finally, great signal-to-noise for one-quantum transitions is obtained using electronic feedback to realize the first one-particle self-excited oscillator. The new methods may also allow a million times improved measurement of the 500 times small antiproton magnetic moment.

  19. Thermal emission and absorption of radiation in finite inverted-opal photonic crystals

    SciTech Connect (OSTI)

    Florescu, Marian; Stimpson, Andrew J.; Lee, Hwang; Dowling, Jonathan

    2005-09-15

    We study theoretically the optical properties of a finite inverted-opal photonic crystal. The light-matter interaction is strongly affected by the presence of the three-dimensional photonic crystal and the alterations of the light emission and absorption processes can be used to suppress or enhance the thermal emissivity and absorptivity of the dielectric structure. We investigate the influence of the absorption present in the system on the relevant band edge frequencies that control the optical response of the photonic crystal. Our study reveals that the absorption processes cause spectral broadening and shifting of the band edge optical resonances, and determine a strong reduction of the photonic band gap spectral range. Using the angular and spectral dependence of the band edge frequencies for stop bands along different directions, we argue that by matching the blackbody emission spectrum peak with a prescribed maximum of the absorption coefficient, it is possible to achieve an angle-sensitive enhancement of the thermal emission/absorption of radiation. This result opens a way to realize a frequency-sensitive and angle-sensitive photonic crystal absorbers/emitters.

  20. Spectrographic temperature measurement of a high power breakdown arc in a high pressure gas switch

    SciTech Connect (OSTI)

    Yeckel, Christopher; Curry, Randy

    2011-09-15

    A procedure for obtaining an approximate temperature value of conducting plasma generated during self-break closure of a RIMFIRE gas switch is described. The plasma is in the form of a breakdown arc which conducts approximately 12 kJ of energy in 1 {mu}s. A spectrographic analysis of the trigger-section of the 6-MV RIMFIRE laser triggered gas switch used in Sandia National Laboratory's ''Z-Machine'' has been made. It is assumed that the breakdown plasma has sufficiently approached local thermodynamic equilibrium allowing a black-body temperature model to be applied. This model allows the plasma temperature and radiated power to be approximated. The gas dielectric used in these tests was pressurized SF{sub 6}. The electrode gap is set at 4.59 cm for each test. The electrode material is stainless steel and insulator material is poly(methyl methacrylate). A spectrum range from 220 to 550 nanometers has been observed and calibrated using two spectral irradiance lamps and three spectrograph gratings. The approximate plasma temperature is reported.

  1. Apparatus and method for transient thermal infrared spectrometry of flowable enclosed materials

    DOE Patents [OSTI]

    McClelland, John F.; Jones, Roger W.

    1993-03-02

    A method and apparatus for enabling analysis of a flowable material enclosed in a transport system having an infrared transparent wall portion. A temperature differential is transiently generated between a thin surface layer portion of the material and a lower or deeper portion of the material sufficient to alter the thermal infrared emission spectrum of the material from the black-body thermal infrared emission spectrum of the material, and the altered thermal infrared emission spectrum is detected through the infrared transparent portion of the transport system while the altered thermal infrared emission spectrum is sufficiently free of self-absorption by the material of emitted infrared radiation. The detection is effected prior to the temperature differential propagating into the lower or deeper portion of the material to an extent such that the altered thermal infrared emission spectrum is no longer sufficiently free of self-absorption by the material of emitted infrared radiation. By such detection, the detected altered thermal infrared emission spectrum is indicative of characteristics relating to molecular composition of the material.

  2. Apparatus and method for transient thermal infrared spectrometry

    DOE Patents [OSTI]

    McClelland, John F.; Jones, Roger W.

    1991-12-03

    A method and apparatus for enabling analysis of a material (16, 42) by applying a cooling medium (20, 54) to cool a thin surface layer portion of the material and to transiently generate a temperature differential between the thin surface layer portion and the lower portion of the material sufficient to alter the thermal infrared emission spectrum of the material from the black-body thermal infrared emission spectrum of the material. The altered thermal infrared emission spectrum of the material is detected by a spectrometer/detector (28, 50) while the altered thermal infrared emission spectrum is sufficiently free of self-absorption by the material of the emitted infrared radiation. The detection is effected prior to the temperature differential propagating into the lower portion of the material to an extent such that the altered thermal infrared emission spectrum is no longer sufficiently free of self-absorption by the material of emitted infrared radiation, so that the detected altered thermal infrared emission spectrum is indicative of the characteristics relating to the molecular composition of the material.

  3. 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.

  4. Time-dependent, x-ray spectral unfolds and brightness temperatures for intense Li{sup +} ion beam-driven hohlraums

    SciTech Connect (OSTI)

    Fehl, D.L.; Chandler, G.A.; Biggs, F.; Dukart, R.J.; Moats, A.R.; Leeper, R.J.

    1997-01-01

    X-ray-producing hohlraums are being studied as indirect drives for inertial confinement fusion targets. In a 1994 target series on the PBFAII accelerator, cylindrical hohlraum targets were heated by an intense Li{sup +} ion beam and viewed by an array of 13 time-resolved, filtered x-ray detectors (XRDs). The unfold operator (UFO) code and its suite of auxiliary functions were used extensively in obtaining time-resolved x-ray spectra and radiation temperatures from this diagnostic. The UFO was also used to obtain fitted response functions from calibration data, to simulate data from blackbody x-ray spectra of interest, to determine the suitability of various unfolding parameters (e.g., energy domain, energy partition, smoothing conditions, and basis functions), to interpolate the XRD signal traces, and to unfold experimental data. The simulation capabilities of the code were useful in understanding an anomalous feature in the unfolded spectra at low photon energies ({le}100 eV). Uncertainties in the differential and energy-integrated unfolded spectra were estimated from uncertainties in the data. The time{endash}history of the radiation temperature agreed well with independent calculations of the wall temperature in the hohlraum. {copyright} {ital 1997 American Institute of Physics.}

  5. Verification of unfold error estimates in the UFO code

    SciTech Connect (OSTI)

    Fehl, D.L.; Biggs, F.

    1996-07-01

    Spectral unfolding is an inverse mathematical operation which attempts to obtain spectral source information from a set of tabulated response functions and data measurements. Several unfold algorithms have appeared over the past 30 years; among them is the UFO (UnFold Operator) code. In addition to an unfolded spectrum, UFO also estimates the unfold uncertainty (error) induced by running the code in a Monte Carlo fashion with prescribed data distributions (Gaussian deviates). In the problem studied, data were simulated from an arbitrarily chosen blackbody spectrum (10 keV) and a set of overlapping response functions. The data were assumed to have an imprecision of 5% (standard deviation). 100 random data sets were generated. The built-in estimate of unfold uncertainty agreed with the Monte Carlo estimate to within the statistical resolution of this relatively small sample size (95% confidence level). A possible 10% bias between the two methods was unresolved. The Monte Carlo technique is also useful in underdetemined problems, for which the error matrix method does not apply. UFO has been applied to the diagnosis of low energy x rays emitted by Z-Pinch and ion-beam driven hohlraums.

  6. Time-dependent, x-ray spectral unfolds and brightness temperatures for intense Li{sup +} ion beam-driven hohlraums

    SciTech Connect (OSTI)

    Fehl, D.L.; Chandler, G.A.; Biggs, F.; Dukart, R.J.; Moats, A.R.; Leeper, R.J.

    1996-07-01

    X-ray-producing hohlraums are being studied as indirect drives for Inertial Confinement Fusion targets. In a 1994 target series on the PBFAII accelerator, cylindrical hohlraum targets were heated by an intense Li{sup +} ion beam and viewed by an array of 13 time-resolved, filtered x-ray detectors (XRDs). The UFO unfold code and its suite of auxiliary functions were used extensively in obtaining time- resolved x-ray spectra and radiation temperatures from this diagnostic. UFO was also used to obtain fitted response functions from calibration data, to simulate data from blackbody x-ray spectra of interest, to determine the suitability of various unfolding parameters (e.g., energy domain, energy partition, smoothing conditions, and basis functions), to interpolate the XRD signal traces, and to unfold experimental data. The simulation capabilities of the code were useful in understanding an anomalous feature in the unfolded spectra at low photon energies ({le} 100 eV). Uncertainties in the differential and energy-integrated unfolded spectra were estimated from uncertainties in the data. The time-history of the radiation temperature agreed well with independent calculations of the wall temperature in the hohlraum.

  7. Verification of unfold error estimates in the unfold operator code

    SciTech Connect (OSTI)

    Fehl, D.L.; Biggs, F.

    1997-01-01

    Spectral unfolding is an inverse mathematical operation that attempts to obtain spectral source information from a set of response functions and data measurements. Several unfold algorithms have appeared over the past 30 years; among them is the unfold operator (UFO) code written at Sandia National Laboratories. In addition to an unfolded spectrum, the UFO code also estimates the unfold uncertainty (error) induced by estimated random uncertainties in the data. In UFO the unfold uncertainty is obtained from the error matrix. This built-in estimate has now been compared to error estimates obtained by running the code in a Monte Carlo fashion with prescribed data distributions (Gaussian deviates). In the test problem studied, data were simulated from an arbitrarily chosen blackbody spectrum (10 keV) and a set of overlapping response functions. The data were assumed to have an imprecision of 5{percent} (standard deviation). One hundred random data sets were generated. The built-in estimate of unfold uncertainty agreed with the Monte Carlo estimate to within the statistical resolution of this relatively small sample size (95{percent} confidence level). A possible 10{percent} bias between the two methods was unresolved. The Monte Carlo technique is also useful in underdetermined problems, for which the error matrix method does not apply. UFO has been applied to the diagnosis of low energy x rays emitted by Z-pinch and ion-beam driven hohlraums. {copyright} {ital 1997 American Institute of Physics.}

  8. Melter viewing system for liquid-fed ceramic melters

    SciTech Connect (OSTI)

    Westsik, J.H. Jr.; Brenden, B.B.

    1988-01-01

    Melter viewing systems are an integral component of the monitoring and control systems for liquid-fed ceramic melters. The Pacific Northwest Laboratory (PNL) has designed cameras for use with glass melters at PNL, the Hanford Waste Vitrification Plant (HWVP), and West Valley Demonstration Project (WVDP). This report is a compilation of these designs. Operating experiences with one camera designed for the PNL melter are discussed. A camera has been fabricated and tested on the High-Bay Ceramic Melter (HBCM) and the Pilot-Scale Ceramic Melter (PSCM) at PNL. The camera proved to be an effective tool for monitoring the cold cap formed as the feed pool developed on the molten glass surface and for observing the physical condition of the melter. Originally, the camera was built to operate using the visible light spectrum in the melter. It was later modified to operate using the infrared (ir) spectrum. In either configuration, the picture quality decreases as the size of the cold cap increases. Large cold caps cover the molten glass, reducing the amount of visible light and reducing the plenum temperatures below 600/sup 0/C. This temperature corresponds to the lowest level of blackbody radiation to which the video tube is sensitive. The camera has been tested in melter environments for about 1900 h. The camera has withstood mechanical shocks and vibrations. The cooling system in the camera has proved effective in maintaining the optical and electronic components within acceptable temperature ranges. 10 refs., 15 figs.

  9. A SIGNIFICANT POPULATION OF CANDIDATE NEW MEMBERS OF THE {rho} OPHIUCHI CLUSTER

    SciTech Connect (OSTI)

    Barsony, Mary; Haisch, Karl E.; Marsh, Kenneth A.; McCarthy, Chris E-mail: Karl.Haisch@uvu.edu E-mail: exoplanet@gmail.com

    2012-05-20

    We present a general method for identifying the pre-main-sequence population of any star-forming region, unbiased with respect to the presence or absence of disks, in contrast to samples selected primarily via their mid-infrared emission from Spitzer surveys. We have applied this technique to a new, deep, wide-field, near-infrared imaging survey of the {rho} Ophiuchi cloud core to search for candidate low-mass members. In conjunction with published Spitzer IRAC photometry and least-squares fits of model spectra (COND, DUSTY, NextGen, and blackbody) to the observed spectral energy distributions, we have identified 948 candidate cloud members within our 90% completeness limits of J = 20.0, H = 20.0, and K{sub s} = 18.50. This population represents a factor of {approx}3 increase in the number of known young stellar objects in the {rho} Ophiuchi cloud. A large fraction of the candidate cluster members (81% {+-} 3%) exhibit infrared excess emission consistent with the presence of disks, thus strengthening the possibility of their being bona fide cloud members. Spectroscopic follow-up will confirm the nature of individual objects, better constrain their parameters, and allow an initial mass function to be derived.

  10. A tidal disruption event in a nearby galaxy hosting an intermediate mass black hole

    SciTech Connect (OSTI)

    Donato, D.; Troja, E.; Pursimo, T.; Cheung, C. C.; Kutyrev, A.; Landt, H.; Butler, N. R.

    2014-02-01

    We report the serendipitous discovery of a bright point source flare in the Abell cluster A1795 with archival EUVE and Chandra observations. Assuming the EUVE emission is associated with the Chandra source, the X-ray 0.5-7 keV flux declined by a factor of ?2300 over a time span of 6 yr, following a power-law decay with index ?2.44 0.40. The Chandra data alone vary by a factor of ?20. The spectrum is well fit by a blackbody with a constant temperature of kT ? 0.09 keV (?10{sup 6} K). The flare is spatially coincident with the nuclear region of a faint, inactive galaxy with a photometric redshift consistent at the 1? level with the cluster (z = 0.062476). We argue that these properties are indicative of a tidal disruption of a star by a black hole (BH) with log (M {sub BH}/M {sub ?}) ? 5.5 0.5. If so, such a discovery indicates that tidal disruption flares may be used to probe BHs in the intermediate mass range, which are very difficult to study by other means.

  11. Nanoparticle generation and transport resulting from femtosecond laser ablation of ultrathin metal films: Time-resolved measurements and molecular dynamics simulations

    SciTech Connect (OSTI)

    Rouleau, C. M. Puretzky, A. A.; Geohegan, D. B.; Shih, C.-Y.; Wu, C.; Zhigilei, L. V.

    2014-05-12

    The synthesis of metal nanoparticles by ultrafast laser ablation of nanometers-thick metal films has been studied experimentally and computationally. Near-threshold backside laser ablation of 2–20 nm-thick Pt films deposited on fused silica substrates was found to produce nanoparticles with size distributions that were bimodal for the thicker films, but collapsed into a single mode distribution for the thinnest film. Time-resolved imaging of blackbody emission from the Pt nanoparticles was used to reveal the nanoparticle propagation dynamics and estimate their temperatures. The observed nanoparticle plume was compact and highly forward-directed with a well-defined collective velocity that permitted multiple rebounds with substrates to be revealed. Large-scale molecular dynamics simulations were used to understand the evolution of compressive and tensile stresses in the thicker melted liquid films that lead to their breakup and ejection of two groups of nanoparticles with different velocity and size distributions. Ultrafast laser irradiation of ultrathin (few nm) metal films avoids the splitting of the film and appears to be a method well-suited to cleanly synthesize and deposit nanoparticles from semitransparent thin film targets in highly directed beams.

  12. Lifecycle of laser-produced air sparks

    SciTech Connect (OSTI)

    Harilal, S. S. Brumfield, B. E.; Phillips, M. C.

    2015-06-15

    We investigated the lifecycle of laser-generated air sparks or plasmas using multiple plasma diagnostic tools. The sparks were generated by focusing the fundamental radiation from an Nd:YAG laser in air, and studies included early and late time spark dynamics, decoupling of the shock wave from the plasma core, emission from the spark kernel, cold gas excitation by UV radiation, shock waves produced by the air spark, and the spark's final decay and turbulence formation. The shadowgraphic and self-emission images showed similar spark morphology at earlier and late times of its lifecycle; however, significant differences are seen in the midlife images. Spectroscopic studies in the visible region showed intense blackbody-type radiation at early times followed by clearly resolved ionic, atomic, and molecular emission. The detected spectrum at late times clearly contained emission from both CN and N{sub 2}{sup +}. Additional spectral features have been identified at late times due to emission from O and N atoms, indicating some degree of molecular dissociation and excitation. Detailed spatially and temporally resolved emission analysis provides insight about various physical mechanisms leading to molecular and atomic emission by air sparks, including spark plasma excitation, heating of cold air by UV radiation emitted by the spark, and shock-heating.

  13. X- and γ-ray pulsations of the nearby radio-faint PSR J1741–2054

    SciTech Connect (OSTI)

    Marelli, M.; Belfiore, A.; Caraveo, P.; De Luca, A.; Salvetti, D.; Saz Parkinson, P.; Sarazin, C.; Sivakoff, G. R.; Camilo, F.

    2014-07-20

    We report the results of a deep XMM-Newton observation of the radio-faint γ-ray pulsar J1741–2054 and its nebula together with the analysis of five years of Fermi Large Area Telescope (LAT) data. The X-ray spectrum of the pulsar is consistent with an absorbed power law plus a blackbody, originating at least partly from the neutron star cooling. The nebular emission is consistent with that of a synchrotron pulsar wind nebula, with hints of spatial spectral variation. We extended the available Fermi LAT ephemeris and folded the γ-ray and X-ray data. We detected X-ray pulsations from the neutron star: both the thermal and non-thermal components are ∼35%-40% pulsed, with phase-aligned maxima. A sinusoid fits the thermal-folded profile well. A 10 bin phase-resolved analysis of the X-ray emission shows softening of the non-thermal spectrum during the on-pulse phases. The radio, X-ray, and γ-ray light curves are single-peaked, not phase-aligned, with the X-ray peak trailing the γ-ray peak by more than half a rotation. Spectral considerations suggest that the most probable pulsar distance is in the 0.3-1.0 kpc range, in agreement with the radio dispersion measure.

  14. Characterizing mid-ultraviolet to optical light curves of nearby type IIn supernovae

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

    de la Rosa, Janie; Roming, Pete; Pritchard, Tyler; Fryer, Chris

    2016-03-21

    Here, we present early mid-ultraviolet and optical observations of Type IIn supernovae (SNe IIn) observed from 2007 to 2013. Our results focus on the properties of UV light curves: peak absolute magnitudes, temporal decay, and color evolution. During early times, this sample demonstrates that UV light decays faster than optical, and each event transitions from a predominantly UV-bright phase to an optically bright phase. In order to understand early UV behavior, we generate and analyze the sample's blackbody luminosity, temperature, and radius as the SN ejecta expand and cool. Since most of our observations were detected post maximum luminosity, wemore » introduce a method for estimating the date of peak magnitude. When our observations are compared based on filter, we find that even though these SNe IIn vary in peak magnitudes, there are similarities in UV decay rates. We use a simple semi-analytical SN model in order to understand the effects of the explosion environment on our UV observations. Understanding the UV characteristics of nearby SNe IIn during an early phase can provide valuable information about the environment surrounding these explosions, leading us to evaluating the diversity of observational properties in this subclass.« less

  15. Imaging sensors and displays. SPIE volume 765

    SciTech Connect (OSTI)

    Freeman, C.F.

    1987-01-01

    This book discusses the following contents: HUMAN FACTORS FOR IMAGING SYSTEMS. Analysis of electroluminescent display devices for stereographic display of video images. Field of view, resolution, and brightness parameters for eye-limited displays. Helmet-mounted display for tank applications. Temporal aspects of electro-optical imaging systems. Helmet-mounted display for infantry applications. Image quality: two current issues. ADVANCED IMAGING SENSOR TECHNOLOGY. New color coding method with quasi-field integration mode for solid-state color imaging equipment. One-half inch CCD imager with 510 X 492 pixels. Solid-state imager implementing sensitivity control function on chip. Color laser microscope. A channel stop defined, barrier and drain antiblooming structure for virtual phase CCD image sensors. ADVANCED IMAGING DISPLAYS. Ultrahigh resolution 7 in. round monochrome CRT. High resolution MIM-diode LCD addressed by storage capacitor matrix. IMAGE DISPLAY TECHNOLOGY FOR INFRARED PROJECTORS. IR transducer technology: an overview. IT emitting CRT. IR simulation using the liquid crystal light valve (LCLV). Infrared display array. IR image generation by thermoelectric elements. IR simulation with diffusion image transfer film. Dynamic RAM imaging display technology utilizing silicon blackbody emitters. Thermal target projector for MRTD testing and vehicle identification training.

  16. HOT DEBRIS DUST AROUND HD 106797

    SciTech Connect (OSTI)

    Fujiwara, Hideaki; Onaka, Takashi; Yamashita, Takuya; Ishihara, Daisuke; Kataza, Hirokazu; Ootsubo, Takafumi; Murakami, Hiroshi; Nakagawa, Takao; Hirao, Takanori; Enya, Keigo; Fukagawa, Misato; Marshall, Jonathan P.; White, Glenn J.

    2009-04-10

    Photometry of the A0 V main-sequence star HD 106797 with AKARI and Gemini/T-ReCS is used to detect excess emission over the expected stellar photospheric emission between 10 and 20 {mu}m, which is best attributed to hot circumstellar debris dust surrounding the star. The temperature of the debris dust is derived as T {sub d} {approx} 190 K by assuming that the excess emission is approximated by a single temperature blackbody. The derived temperature suggests that the inner radius of the debris disk is {approx}14 AU. The fractional luminosity of the debris disk is 1000 times brighter than that of our own zodiacal cloud. The existence of such a large amount of hot dust around HD 106797 cannot be accounted for by a simple model of the steady state evolution of a debris disk due to collisions, and it is likely that transient events play a significant role. Our data also show a narrow spectral feature between 11 and 12 {mu}m attributable to crystalline silicates, suggesting that dust heating has occurred during the formation and evolution of the debris disk of HD 106797.

  17. CONSTRAINTS ON THE SYNCHROTRON SHOCK MODEL FOR THE FERMI GRB 090820A OBSERVED BY GAMMA-RAY BURST MONITOR

    SciTech Connect (OSTI)

    Burgess, J. Michael; Preece, Robert D.; Briggs, Michael S.; Connaughton, Valerie; Guiriec, Sylvain; Paciesas, William S.; Bhat, P. N.; Chaplin, Vandiver; Goldstein, Adam; Baring, Matthew G.; Meegan, Charles A.; Bissaldi, Elisabetta; Diehl, Roland; Greiner, Jochen; Gruber, David; Fishman, Gerald J.; Gibby, Melissa; Giles, Misty E-mail: baring@rice.edu

    2011-11-01

    Discerning the radiative dissipation mechanism for prompt emission in gamma-ray bursts (GRBs) requires detailed spectroscopic modeling that straddles the {nu}F{sub {nu}} peak in the 100 keV-1 MeV range. Historically, empirical fits such as the popular Band function have been employed with considerable success in interpreting the observations. While extrapolations of the Band parameters can provide some physical insight into the emission mechanisms responsible for GRBs, these inferences do not provide a unique way of discerning between models. By fitting physical models directly, this degeneracy can be broken, eliminating the need for empirical functions; our analysis here offers a first step in this direction. One of the oldest, and leading, theoretical ideas for the production of the prompt signal is the synchrotron shock model. Here we explore the applicability of this model to a bright Fermi gamma-ray burst monitor (GBM) burst with a simple temporal structure, GRB 090820A. Our investigation implements, for the first time, thermal and non-thermal synchrotron emissivities in the RMFIT forward-folding spectral analysis software often used in GBM burst studies. We find that these synchrotron emissivities, together with a blackbody shape, provide at least as good a match to the data as the Band GRB spectral fitting function. This success is achieved in both time-integrated and time-resolved spectral fits.

  18. HUBBLE SPACE TELESCOPE DETECTION OF THE DOUBLE PULSAR SYSTEM J07373039 IN THE FAR-ULTRAVIOLET

    SciTech Connect (OSTI)

    Durant, Martin; Kargaltsev, Oleg; Pavlov, George G. E-mail: kargaltsev@email.gwu.edu

    2014-03-01

    We report on detection of the double pulsar system J07373039 in the far-UV with the Advanced Camera for Surveys/Solar-blind Channel detector aboard Hubble Space Telescope. We measured the energy flux F = (4.6 1.0) 10{sup 17}ergcm{sup 2} s{sup 1} in the 1250-1550 band, which corresponds to the extinction-corrected luminosity L ? 1.5 10{sup 28}ergs{sup 1} for the distance d = 1.1kpc and a plausible reddening E(B V) = 0.1. If the detected emission comes from the entire surface of one of the neutron stars with a 13km radius, the surface blackbody temperature is in the range T ? (2-5) 10{sup 5}K for a reasonable range of interstellar extinction. Such a temperature requires an internal heating mechanism to operate in old neutron stars, or, less likely, it might be explained by heating of the surface of the less energetic Pulsar B by the relativistic wind of Pulsar A. If the far-ultraviolet emission is non-thermal (e.g., produced in the magnetosphere of Pulsar A), its spectrum exhibits a break between the UV and X-rays.

  19. Water vapor in the spectrum of the extrasolar planet HD 189733b. II. The eclipse

    SciTech Connect (OSTI)

    Crouzet, Nicolas; McCullough, Peter R.; Deming, Drake; Madhusudhan, Nikku

    2014-11-10

    Spectroscopic observations of exoplanets are crucial to infer the composition and properties of their atmospheres. HD 189733b is one of the most extensively studied exoplanets and is a cornerstone for hot Jupiter models. In this paper, we report the dayside emission spectrum of HD 189733b in the wavelength range 1.1-1.7 μm obtained with the Hubble Space Telescope Wide Field Camera 3 (WFC3) in spatial scan mode. The quality of the data is such that even a straightforward analysis yields a high-precision Poisson noise-limited spectrum: the median 1σ uncertainty is 57 ppm per 0.02 μm bin. We also build a white-light curve correcting for systematic effects and derive an absolute eclipse depth of 96 ± 39 ppm. The resulting spectrum shows marginal evidence for water vapor absorption, but can also be well explained by a blackbody spectrum. However, the combination of these WFC3 data with previous Spitzer photometric observations is best explained by a dayside atmosphere of HD 189733b with no thermal inversion and a nearly solar or subsolar H{sub 2}O abundance in a cloud-free atmosphere. Alternatively, this apparent subsolar abundance may be the result of clouds or hazes that future studies need to investigate.

  20. ARCADE 2 MEASUREMENT OF THE ABSOLUTE SKY BRIGHTNESS AT 3-90 GHz

    SciTech Connect (OSTI)

    Fixsen, D. J.; Levin, S.; Seiffert, M.; Limon, M.; Lubin, P.; Mirel, P.; Singal, J.; Villela, T.; Wuensche, C. A.

    2011-06-10

    The ARCADE 2 instrument has measured the absolute temperature of the sky at frequencies 3, 8, 10, 30, and 90 GHz, using an open-aperture cryogenic instrument observing at balloon altitudes with no emissive windows between the beam-forming optics and the sky. An external blackbody calibrator provides an in situ reference. Systematic errors were greatly reduced by using differential radiometers and cooling all critical components to physical temperatures approximating the cosmic microwave background (CMB) temperature. A linear model is used to compare the output of each radiometer to a set of thermometers on the instrument. Small corrections are made for the residual emission from the flight train, balloon, atmosphere, and foreground Galactic emission. The ARCADE 2 data alone show an excess radio rise of 54 {+-} 6 mK at 3.3 GHz in addition to a CMB temperature of 2.731 {+-} 0.004 K. Combining the ARCADE 2 data with data from the literature shows an excess power-law spectrum of T = 24.1 {+-} 2.1 (K) ({nu}/{nu}{sub 0}){sup -2.599{+-}0.036} from 22 MHz to 10 GHz ({nu}{sub 0} = 310 MHz) in addition to a CMB temperature of 2.725 {+-} 0.001 K.

  1. Type IIP supernovae as cosmological probes: A SEAM distance to SN1999em

    SciTech Connect (OSTI)

    Baron, E.; Nugent, Peter E.; Branch, David; Hauschildt, Peter H.

    2004-06-01

    Because of their intrinsic brightness, supernovae make excellent cosmological probes. We describe the spectral-fitting expanding atmosphere method (SEAM) for obtaining distances to Type IIP supernovae (SNe IIP) and present a distance to SN 1999em for which a Cepheid distance exists. Our models give results consistent with the Cepheid distance, even though we have not attempted to tune the underlying hydrodynamical model but have simply chosen the best fits. This is in contradistinction to the expanding photosphere method (EPM), which yields a distance to SN 1999em that is 50 percent smaller than the Cepheid distance. We emphasize the differences between the SEAM and the EPM. We show that the dilution factors used in the EPM analysis were systematically too small at later epochs. We also show that the EPM blackbody assumption is suspect. Since SNe IIP are visible to redshifts as high as z {approx}< 6, with the James Webb Space Telescope, the SEAM may be a valuable probe of the early universe.

  2. Thermal nuclear pulse simulation at the National Solar Thermal Test Facility

    SciTech Connect (OSTI)

    Cameron, C.P.; Ralph, M.E. ); Ghanbari, C.M. ); Oeding, R.; Shaw, K. )

    1991-01-01

    The National Solar Thermal Test Facility (NSTTF) at Sandia National Laboratories in Albuquerque, New Mexico is being used to simulate the thermal pulse from a nuclear weapon on relatively large surfaces. Pulses varying in length from 2 seconds to 7 seconds have been produced. The desired pulse length varies as a function of the yield of the weapon being simulated. The present experiment capability can accommodate samples as large as 1.2 {times} 1.5 meters. Samples can be flat or three-dimensional. Samples exposed have ranged from fabrics (protective clothing) to an aircraft canopy and cockpit system, complete with a mannequin in a flight suit and helmet. In addition, a windowed wind tunnel has been constructed which permits exposure of flight surface materials to thermal transients with air speed of Mach 0.8. The wind tunnel can accommodate samples up to .48 {times} .76 meters or an array of smaller samples. The maximum flux capability of the NSTTF is about 70 calories/cm{sup 2}-sec. A black-body temperature of about 6000 K is produced by the solar beam and is therefore ideal for simulating the nuclear source. 3 refs., 7 figs.

  3. Transparency parameters from relativistically expanding outflows

    SciTech Connect (OSTI)

    Bgu, D. [University of Roma "Sapienza," I-00185, p.le A. Moro 5, Rome (Italy); Iyyani, S. [Department of Physics, KTH Royal Institute of Technology, AlbaNova University Center, SE-106 91 Stockholm (Sweden)

    2014-09-01

    In many gamma-ray bursts a distinct blackbody spectral component is present, which is attributed to the emission from the photosphere of a relativistically expanding plasma. The properties of this component (temperature and flux) can be linked to the properties of the outflow and have been presented in the case where there is no sub-photospheric dissipation and the photosphere is in coasting phase. First, we present the derivation of the properties of the outflow for finite winds, including when the photosphere is in the accelerating phase. Second, we study the effect of localized sub-photospheric dissipation on the estimation of the parameters. Finally, we apply our results to GRB 090902B. We find that during the first epoch of this burst the photosphere is most likely to be in the accelerating phase, leading to smaller values of the Lorentz factor than the ones previously estimated. For the second epoch, we find that the photosphere is likely to be in the coasting phase.

  4. Structure and method for controlling the thermal emissivity of a radiating object

    DOE Patents [OSTI]

    DeSteese, John G.; Antoniak, Zenen I.; White, Michael; Peters, Timothy J.

    2004-03-30

    A structure and method for changing or controlling the thermal emissivity of the surface of an object in situ, and thus, changing or controlling the radiative heat transfer between the object and its environment in situ, is disclosed. Changing or controlling the degree of blackbody behavior of the object is accomplished by changing or controlling certain physical characteristics of a cavity structure on the surface of the object. The cavity structure, defining a plurality of cavities, may be formed by selectively removing material(s) from the surface, selectively adding a material(s) to the surface, or adding an engineered article(s) to the surface to form a new radiative surface. The physical characteristics of the cavity structure that are changed or controlled include cavity area aspect ratio, cavity longitudinal axis orientation, and combinations thereof. Controlling the cavity area aspect ratio may be by controlling the size of the cavity surface area, the size of the cavity aperture area, or a combination thereof. The cavity structure may contain a gas, liquid, or solid that further enhances radiative heat transfer control and/or improves other properties of the object while in service.

  5. An Analysis of Recent Measurements of the Temperature of the Cosmic Microwave Background Radiation

    DOE R&D Accomplishments [OSTI]

    Smoot, G.; Levin, S. M.; Witebsky, C.; De Amici, G.; Rephaeli, Y.

    1987-07-01

    This paper presents an analysis of the results of recent temperature measurements of the cosmic microwave background radiation (CMBR). The observations for wavelengths longer than 0.1 cum are well fit by a blackbody spectrum at 2.74{+ or -}0.0w K; however, including the new data of Matsumoto et al. (1987) the result is no longer consistent with a Planckian spectrum. The data are described by a Thomson-distortion parameter u=0.021{+ or -}0.002 and temperature 2.823{+ or -}0.010 K at the 68% confidence level. Fitting the low-frequency data to a Bose-Einstein spectral distortion yields a 95% confidence level upper limit of 1.4 x 10{sup -2} on the chemical potential mu{sub 0}. These limits on spectral distortions place restrictions on a number of potentially interesting sources of energy release to the CMBR, including the hot intergalactic medium proposed as the source of the X-ray background.

  6. Deconvolving X-ray spectral variability components in the Seyfert 1.5 NGC 3227

    SciTech Connect (OSTI)

    Arvalo, P.; Markowitz, A.

    2014-03-10

    We present the variability analysis of a 100 ks XMM-Newton observation of the Seyfert 1.5 active galaxy, NGC 3227. The observation found NGC 3227 in a period where its hard power-law component displayed remarkably little long-term variability. This lucky event allows us to clearly observe a soft spectral component undergoing a large-amplitude but slow flux variation. Using combined spectral and timing analysis, we isolate two independent variable continuum components and characterize their behavior as a function of timescale. Rapid and coherent variations throughout the 0.2-10 keV band reveal a spectrally hard (photon index ? ? 1.7-1.8) power law, dominating the observed variability on timescales of 30 ks and shorter. Another component produces coherent fluctuations in the 0.2-2 keV range and is much softer (? ? 3); it dominates the observed variability on timescales greater than 30 ks. Both components are viewed through the same absorbers identified in the time-averaged spectrum. The combined spectral and timing analysis breaks the degeneracy between models for the soft excess: it is consistent with a power-law or thermal Comptonized component but not with a blackbody or an ionized reflection component. We demonstrate that the rapid variability in NGC 3227 is intrinsic to continuum-emitting components and is not an effect of variable absorption.

  7. Study of the effects of ambient conditions upon the performance of fan powered, infrared, natural gas burners. Quarterly technical progress report, July 1--September 30, 1995

    SciTech Connect (OSTI)

    Bai, T.; Yeboah, Y.D.; Sampath, R.

    1995-10-01

    The objective of this investigation is to characterize the operation of fan powered infrared burner (PIR) at various gas compositions and ambient conditions and develop design guidelines for appliances in containing PIR burners for satisfactory performance. During this period, experimental setup with optical and electronic instrumentation that is necessary for measuring the radiant heat output and the emission gas output of the burner has been established. The radiation measurement instrument, an FTIR, has been purchased and installed in the porous burner experimental system. The radiation measurement capability of the FTIR was tested and found to be satisfactory. A standard blackbody source, made by Graseby Infrared, was employed to calibrate the FTIR. A collection duct for emission gas measurement was fabricated and connected to the existing Horiba gas analyzer. Test runs are being conducted for flue gas analysis. A number of published research papers on modeling of porous burners were reviewed. The physical mechanism and theoretical analysis of the combustion process of the PIR burner was formulated. The numerical modeling, and implementation of a PIR burner code at CAU`s computing facility is in progress.

  8. GALEX AND PAN-STARRS1 DISCOVERY OF SN IIP 2010aq: THE FIRST FEW DAYS AFTER SHOCK BREAKOUT IN A RED SUPERGIANT STAR

    SciTech Connect (OSTI)

    Gezari, S.; Huber, M. E.; Grav, T.; Rest, A.; Narayan, G.; Forster, K.; Neill, J. D.; Martin, D. C.; Valenti, S.; Smartt, S. J.; Chornock, R.; Berger, E.; Soderberg, A. M.; Mattila, S.; Kankare, E.; Burgett, W. S.; Chambers, K. C.; Dombeck, T.; Heasley, J. N.; Hodapp, K. W.

    2010-09-01

    We present the early UV and optical light curve of Type IIP supernova (SN) 2010aq at z = 0.0862, and compare it to analytical models for thermal emission following SN shock breakout in a red supergiant star. SN 2010aq was discovered in joint monitoring between the Galaxy Evolution Explorer (GALEX) Time Domain Survey (TDS) in the NUV and the Pan-STARRS1 Medium Deep Survey (PS1 MDS) in the g, r, i, and z bands. The GALEX and Pan-STARRS1 observations detect the SN less than 1 day after the shock breakout, measure a diluted blackbody temperature of 31, 000 {+-} 6000 K 1 day later, and follow the rise in the UV/optical light curve over the next 2 days caused by the expansion and cooling of the SN ejecta. The high signal-to-noise ratio of the simultaneous UV and optical photometry allows us to fit for a progenitor star radius of 700 {+-} 200R {sub sun}, the size of a red supergiant star. An excess in UV emission two weeks after shock breakout compared with SNe well fitted by model atmosphere-code synthetic spectra with solar metallicity is best explained by suppressed line blanketing due to a lower metallicity progenitor star in SN 2010aq. Continued monitoring of PS1 MDS fields by the GALEX TDS will increase the sample of early UV detections of Type II SNe by an order of magnitude and probe the diversity of SN progenitor star properties.

  9. A Hybrid Design of Project-X

    SciTech Connect (OSTI)

    Chou, W.; /Fermilab

    2009-05-01

    Project-X is a leading candidate of the next major accelerator construction project at Fermilab. The mission need of Project-X is to establish an intensity frontier for particle physics research, or more precisely, to build a multi-MW proton source for neutrino and other particle studies. Coupled with an upgraded Main Injector (MI) and Recycler, an 8 GeV superconducting RF (SRF) H- linac meets this need. However, a more cost effective approach would be a hybrid design, namely, a combination of a 2 GeV SRF linac and an 8 GeV rapid cycling synchrotron (RCS) in lieu of an 8 GeV SRF linac. This alternative design also meets the mission need but at a lower cost since a synchrotron is cheaper than a SRF linac. It retains the ability to use a 2 GeV SRF linac for ILC technology development. It reuses the existing Debuncher enclosure and Booster RF. The transport line of 2 GeV H- particles is shorter than the present 8 GeV design since stronger bending magnets can be used. The blackbody radiation stripping of H- particles will no longer be a problem and the requirement of a cryogenic beam screen can be eliminated. The efficiency of stripping foil is higher and injection loss (kJ) will be reduced by a factor of 4. This paper introduces this alternative design and describes briefly the major components in the design.

  10. Modifications to the cosmic 21-cm background frequency spectrum by scattering via electrons in galaxy clusters

    SciTech Connect (OSTI)

    Cooray, Asantha

    2006-05-15

    The cosmic 21-cm background frequency spectrum related to the spin-flip transition of neutral hydrogen present during and before the era of reionization is rich in features associated with physical processes that govern transitions between the two spin states. The intervening electrons in foreground galaxy clusters inversely Compton scatter the 21-cm background spectrum and modify it just as the cosmic microwave background (CMB) spectrum is modified by inverse-Compton scattering. Towards typical galaxy clusters at low redshifts, the resulting modification is a few tenths milli-Kelvin correction to the few tens milli-Kelvin temperature of 21-cm signal relative to that of the cosmic microwave background blackbody spectrum. The modifications are mostly associated with sharp changes in the cosmic 21-cm background spectrum such as due to the onset of a Lyman-{alpha} radiation field or heating of neutral gas. Though low-frequency radio interferometers that are now planned for 21-cm anisotropy measurements are insensitive to the mean 21-cm spectrum, differential observations of galaxy clusters with these interferometers can be utilized to indirectly establish global features in the 21-cm frequency spectrum. We discuss the feasibility to detect the spectrum modified by clusters and find that, for upcoming interferometers, while a detection towards an individual cluster is challenging, one can average signals over a number of clusters, selected based on the strength of the Sunyave-Zel'dovich effect at high radio frequencies involving CMB scattering alone, to establish the mean 21-cm spectrum.

  11. CONSTRAINING THE OPTICAL EMISSION FROM THE DOUBLE PULSAR SYSTEM J0737-3039

    SciTech Connect (OSTI)

    Ferraro, F. R.; Pallanca, C.; Dalessandro, E.; Lanzoni, B.; Mignani, R. P.; Pellizzoni, A.; Possenti, A.; Burgay, M.; D'Amico, N.; Camilo, F.; Lyne, A. G.; Kramer, M.; Manchester, R. N.

    2012-04-10

    We present the first optical observations of the unique system J0737-3039 (composed of two pulsars, hereafter PSR-A and PSR-B). Ultra-deep optical observations, performed with the High Resolution Camera of the Advanced Camera for Surveys on board the Hubble Space Telescope, could not detect any optical emission from the system down to m{sub F435W} = 27.0 and m{sub F606W} = 28.3. The estimated optical flux limits are used to constrain the three-component (two thermal and one non-thermal) model recently proposed to reproduce the XMM-Newton X-ray spectrum. They suggest the presence of a break at low energies in the non-thermal power-law component of PSR-A and are compatible with the expected blackbody emission from the PSR-B surface. The corresponding efficiency of the optical emission from PSR-A's magnetosphere would be comparable to that of other Myr-old pulsars, thus suggesting that this parameter may not dramatically evolve over a timescale of a few Myr.

  12. Revisiting galactic black hole binary GX 339-4 by using 2007 – 2014 Swift XRT observations

    SciTech Connect (OSTI)

    Azizi, Febrie Ahmad; Vierdayanti, Kiki; Putra, Mahasena

    2015-09-30

    This work aims to study the X-ray properties of the galactic black hole binary GX 339-4. Focus of the study is on exploration of data from Swift-XRT in exclusively photon-counting mode. We use data from 2007 up to August 2014, which contain about 40 pointing observations with level 1 data. The flux of GX 339-4 varies in a factor of 100 during this period of observations. For the purpose of this work, we also try to develop a system to conduct standard SWIFT XRT data reduction automatically, in order to greatly reduce time when working with data bulk, which produces images, lightcurves as well as spectra. We also develop another system to conduct fitting of bulk spectral data with a two-component model, disk blackbody and power-law. The fitting results show that no data have a reduced chi-squared > 2. The fraction of the disk to total flux and the power-law to total flux range from 0.00389 – 0.994 and 0.00605 – 0.996, respectively. From the analysis of the disk component, we obtain the value of the innermost disk radius that does not show any large scale truncation which is in a good agreement with a previous study that used 2007 – 2011 Swift-XRT data, indicating that the systems we developed work properly.

  13. GROUND-BASED DETECTIONS OF THERMAL EMISSION FROM THE DENSE HOT JUPITER WASP-43b IN THE H AND K{sub s} BANDS

    SciTech Connect (OSTI)

    Wang, W.; Zhao, G.; Van Boekel, R.; Henning, Th.; Madhusudhan, N.; Chen, G.

    2013-06-10

    We report new detections of thermal emission from the transiting hot Jupiter WASP-43b in the H and K{sub s} bands as observed at secondary eclipses. The observations were made with the WIRCam instrument on the Canada-France-Hawaii Telescope. We obtained a secondary eclipse depth of 0.103{sub -0.017}{sup +0.017}%$ and 0.194{sub -0.029}{sup +0.029} in the H and K{sub s} bands, respectively. The K{sub s}-band depth is consistent with the previous measurement in the narrow band centered at 2.09 {mu}m by Gillon et al. Our eclipse depths in both bands are consistent with a blackbody spectrum with a temperature of {approx}1850 K, slightly higher than the dayside equilibrium temperature without day-night energy redistribution. Based on theoretical models of the dayside atmosphere of WASP-43b, our data constrain the day-night energy redistribution in the planet to be {approx}< 15%-25%, depending on the metal content in the atmosphere. Combined with energy balance arguments, our data suggest that a strong temperature inversion is unlikely in the dayside atmosphere of WASP-43b. However, a weak inversion cannot be strictly ruled out at the current time. Future observations are required to place detailed constraints on the chemical composition of the atmosphere.

  14. A comparison of absolute calibrations of a radiation thermometer based on a monochromator and a tunable source

    SciTech Connect (OSTI)

    Keawprasert, T.; Anhalt, K.; Taubert, D. R.; Sperling, A.; Schuster, M.; Nevas, S.

    2013-09-11

    An LP3 radiation thermometer was absolutely calibrated at a newly developed monochromator-based set-up and the TUneable Lasers in Photometry (TULIP) facility of PTB in the wavelength range from 400 nm to 1100 nm. At both facilities, the spectral radiation of the respective sources irradiates an integrating sphere, thus generating uniform radiance across its precision aperture. The spectral irradiance of the integrating sphere is determined via an effective area of a precision aperture and a Si trap detector, traceable to the primary cryogenic radiometer of PTB. Due to the limited output power from the monochromator, the absolute calibration was performed with the measurement uncertainty of 0.17 % (k= 1), while the respective uncertainty at the TULIP facility is 0.14 %. Calibration results obtained by the two facilities were compared in terms of spectral radiance responsivity, effective wavelength and integral responsivity. It was found that the measurement results in integral responsivity at the both facilities are in agreement within the expanded uncertainty (k= 2). To verify the calibration accuracy, the absolutely calibrated radiation thermometer was used to measure the thermodynamic freezing temperatures of the PTB gold fixed-point blackbody.

  15. Extreme temperature robust optical sensor designs and fault-tolerant signal processing

    DOE Patents [OSTI]

    Riza, Nabeel Agha; Perez, Frank

    2012-01-17

    Silicon Carbide (SiC) probe designs for extreme temperature and pressure sensing uses a single crystal SiC optical chip encased in a sintered SiC material probe. The SiC chip may be protected for high temperature only use or exposed for both temperature and pressure sensing. Hybrid signal processing techniques allow fault-tolerant extreme temperature sensing. Wavelength peak-to-peak (or null-to-null) collective spectrum spread measurement to detect wavelength peak/null shift measurement forms a coarse-fine temperature measurement using broadband spectrum monitoring. The SiC probe frontend acts as a stable emissivity Black-body radiator and monitoring the shift in radiation spectrum enables a pyrometer. This application combines all-SiC pyrometry with thick SiC etalon laser interferometry within a free-spectral range to form a coarse-fine temperature measurement sensor. RF notch filtering techniques improve the sensitivity of the temperature measurement where fine spectral shift or spectrum measurements are needed to deduce temperature.

  16. 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.

  17. BER Science Network Requirements Workshop -- July 26-27,2007

    SciTech Connect (OSTI)

    Tierney, Brian L.; Dart, Eli

    2008-02-01

    The Energy Sciences Network (ESnet) is the primary provider of network connectivity for the US Department of Energy Office of Science, the single largest supporter of basic research in the physical sciences in the United States of America. In support of the Office of Science programs, ESnet regularly updates and refreshes its understanding of the networking requirements of the instruments, facilities, scientists, and science programs that it serves. This focus has helped ESnet to be a highly successful enabler of scientific discovery for over 20 years. In July 2007, ESnet and the Biological and Environmental Research (BER) Program Office of the DOE Office of Science organized a workshop to characterize the networking requirements of the science programs funded by the BER Program Office. These included several large programs and facilities, including Atmospheric Radiation Measurement (ARM) Program and the ARM Climate Research Facility (ACRF), Bioinformatics and Life Sciences Programs, Climate Sciences Programs, the Environmental Molecular Sciences Laboratory at PNNL, the Joint Genome Institute (JGI). National Center for Atmospheric Research (NCAR) also participated in the workshop and contributed a section to this report due to the fact that a large distributed data repository for climate data will be established at NERSC, ORNL and NCAR, and this will have an effect on ESnet. Workshop participants were asked to codify their requirements in a 'case study' format, which summarizes the instruments and facilities necessary for the science and the process by which the science is done, with emphasis on the network services needed and the way in which the network is used. Participants were asked to consider three time scales in their case studies--the near term (immediately and up to 12 months in the future), the medium term (3-5 years in the future), and the long term (greater than 5 years in the future). In addition to achieving its goal of collecting and characterizing

  18. Computational and experimental study of laminar flames

    SciTech Connect (OSTI)

    Smooke, Mitchell

    2015-05-29

    During the past three years, our research has centered on an investigation of the effects of complex chemistry and detailed transport on the structure and extinction of hydrocarbon flames in coflowing axisymmetric configurations. We have pursued both computational and experimental aspects of the research in parallel on both steady-state and time-dependent systems. The computational work has focused on the application of accurate and efficient numerical methods for the solution of the steady-state and time-dependent boundary value problems describing the various reacting systems. Detailed experimental measurements were performed on axisymmetric coflow flames using two-dimensional imaging techniques. Previously, spontaneous Raman scattering, chemiluminescence, and laser-induced fluorescence were used to measure the temperature, major and minor species profiles. Particle image velocimetry (PIV) has been used to investigate velocity distributions and for calibration of time-varying flames. Laser-induced incandescence (LII) with an extinction calibration was used to determine soot volume fractions, while soot surface temperatures were measured with three-color optical pyrometry using a color digital camera. A blackbody calibration of the camera allows for determination of soot volume fraction as well, which can be compared with the LII measurements. More recently, we have concentrated on a detailed characterization of soot using a variety of techniques including time-resolved LII (TiRe-LII) for soot primary particles sizes, multi-angle light scattering (MALS) for soot radius of gyration, and spectrally-resolved line of sight attenuation (spec-LOSA). Combining the information from all of these soot measurements can be used to determine the soot optical properties, which are observed to vary significantly depending on spatial location and fuel dilution. Our goal has been to obtain a more fundamental understanding of the important fluid dynamic and chemical interactions in

  19. Soft x-ray shock loading and momentum coupling in meteorite and planetary materials.

    SciTech Connect (OSTI)

    Lawrence, R. Jeffery; Remo, John L.; Furnish, Michael David

    2010-12-01

    X-ray momentum coupling coefficients, C{sub M}, were determined by measuring stress waveforms in planetary materials subjected to impulsive radiation loading from the Sandia National Laboratories Z-machine. Results from the velocity interferometry (VISAR) diagnostic provided limited equation-of-state data as well. Targets were iron and stone meteorites, magnesium rich olivine (dunite) solid and powder ({approx}5--300 {mu}m), and Si, Al, and Fe calibration targets. All samples were {approx}1 mm thick and, except for Si, backed by LiF single-crystal windows. The x-ray spectrum included a combination of thermal radiation (blackbody 170--237 eV) and line emissions from the pinch material (Cu, Ni, Al, or stainless steel). Target fluences 0.4--1.7 kJ/cm{sup 2} at intensities 43--260 GW/cm{sup 2} produced front surface plasma pressures 2.6--12.4 GPa. Stress waves driven into the samples were attenuating due to the short ({approx}5 ns) duration of the drive pulse. Attenuating wave impulse is constant allowing accurate C{sub M} measurements provided mechanical impedance mismatch between samples and the window are known. Impedance-corrected C{sub M} determined from rear-surface motion was 1.9--3.1 x 10{sup -5} s/m for stony meteorites, 2.7 and 0.5 x 10{sup -5} s/m for solid and powdered dunite, 0.8--1.4 x 10{sup -5}.

  20. A HERSCHEL AND APEX CENSUS OF THE REDDEST SOURCES IN ORION: SEARCHING FOR THE YOUNGEST PROTOSTARS

    SciTech Connect (OSTI)

    Stutz, Amelia M.; Robitaille, Thomas; Henning, Thomas; Krause, Oliver; Tobin, John J.; Stanke, Thomas; Megeath, S. Thomas; Fischer, William J.; Ali, Babar; Furlan, Elise; Hartmann, Lee; Osorio, Mayra; Wilson, Thomas L.; Allen, Lori; Manoj, P.

    2013-04-10

    We perform a census of the reddest, and potentially youngest, protostars in the Orion molecular clouds using data obtained with the PACS instrument on board the Herschel Space Observatory and the LABOCA and SABOCA instruments on APEX as part of the Herschel Orion Protostar Survey (HOPS). A total of 55 new protostar candidates are detected at 70 {mu}m and 160 {mu}m that are either too faint (m{sub 24} > 7 mag) to be reliably classified as protostars or undetected in the Spitzer/MIPS 24 {mu}m band. We find that the 11 reddest protostar candidates with log {lambda}F{sub {lambda}}70/{lambda}F{sub {lambda}}24 > 1.65 are free of contamination and can thus be reliably explained as protostars. The remaining 44 sources have less extreme 70/24 colors, fainter 70 {mu}m fluxes, and higher levels of contamination. Taking the previously known sample of Spitzer protostars and the new sample together, we find 18 sources that have log {lambda}F{sub {lambda}}70/{lambda}F{sub {lambda}}24 > 1.65; we name these sources 'PACS Bright Red sources', or PBRs. Our analysis reveals that the PBR sample is composed of Class 0 like sources characterized by very red spectral energy distributions (SEDs; T{sub bol} < 45 K) and large values of sub-millimeter fluxes (L{sub smm}/L{sub bol} > 0.6%). Modified blackbody fits to the SEDs provide lower limits to the envelope masses of 0.2-2 M{sub Sun} and luminosities of 0.7-10 L{sub Sun }. Based on these properties, and a comparison of the SEDs with radiative transfer models of protostars, we conclude that the PBRs are most likely extreme Class 0 objects distinguished by higher than typical envelope densities and hence, high mass infall rates.

  1. Ks-BAND DETECTION OF THERMAL EMISSION AND COLOR CONSTRAINTS TO CoRoT-1b: A LOW-ALBEDO PLANET WITH INEFFICIENT ATMOSPHERIC ENERGY REDISTRIBUTION AND A TEMPERATURE INVERSION

    SciTech Connect (OSTI)

    Rogers, Justin C.; Apai, Daniel; Lopez-Morales, Mercedes; Sing, David K.; Burrows, Adam

    2009-12-20

    We report the detection in Ks-band of the secondary eclipse of the hot Jupiter CoRoT-1b from time series photometry with the ARC 3.5 m telescope at Apache Point Observatory. The eclipse shows a depth of 0.336 +- 0.042% and is centered at phase 0.5022{sup +0.0023}{sub -0.0027}, consistent with a zero eccentricity orbit (e cos omega = 0.0035{sup +0.0036}{sub -0.0042}). We perform the first optical to near-infrared multi-band photometric analysis of an exoplanet's atmosphere and constrain the reflected and thermal emissions by combining our result with the recent 0.6, 0.71, and 2.09 mum secondary eclipse detections by Snellen et al., Gillon et al., and Alonso et al. Comparing the multi-wavelength detections to state-of-the-art radiative-convective chemical-equilibrium atmosphere models, we find the near-infrared fluxes difficult to reproduce. The closest blackbody-based and physical models provide the following atmosphere parameters: a temperature T = 2460{sup +80}{sub -160} K; a very low Bond albedo A{sub B} = 0.000{sup +0.081}{sub -0.000}; and an energy redistribution parameter P{sub n} = 0.1, indicating a small but nonzero amount of heat transfer from the day to nightside. The best physical model suggests a thermal inversion layer with an extra optical absorber of opacity kappa{sub e} = 0.05 cm{sup 2} g{sup -1}, placed near the 0.1 bar atmospheric pressure level. This inversion layer is located 10 times deeper in the atmosphere than the absorbers used in models to fit mid-infrared Spitzer detections of other irradiated hot Jupiters.

  2. The ultraviolet-bright, slowly declining transient PS1-11af as a partial tidal disruption event

    SciTech Connect (OSTI)

    Chornock, R.; Berger, E.; Zauderer, B. A.; Kamble, A.; Soderberg, A. M.; Czekala, I.; Dittmann, J.; Drout, M.; Foley, R. J.; Fong, W.; Kirshner, R. P.; Lunnan, R.; Marion, G. H.; Narayan, G.; Gezari, S.; Rest, A.; Riess, A. G.; Chomiuk, L.; Huber, M. E.; Lawrence, A.; and others

    2014-01-01

    We present the Pan-STARRS1 discovery of the long-lived and blue transient PS1-11af, which was also detected by Galaxy Evolution Explorer with coordinated observations in the near-ultraviolet (NUV) band. PS1-11af is associated with the nucleus of an early type galaxy at redshift z = 0.4046 that exhibits no evidence for star formation or active galactic nucleus activity. Four epochs of spectroscopy reveal a pair of transient broad absorption features in the UV on otherwise featureless spectra. Despite the superficial similarity of these features to P-Cygni absorptions of supernovae (SNe), we conclude that PS1-11af is not consistent with the properties of known types of SNe. Blackbody fits to the spectral energy distribution are inconsistent with the cooling, expanding ejecta of a SN, and the velocities of the absorption features are too high to represent material in homologous expansion near a SN photosphere. However, the constant blue colors and slow evolution of the luminosity are similar to previous optically selected tidal disruption events (TDEs). The shape of the optical light curve is consistent with models for TDEs, but the minimum accreted mass necessary to power the observed luminosity is only ?0.002 M {sub ?}, which points to a partial disruption model. A full disruption model predicts higher bolometric luminosities, which would require most of the radiation to be emitted in a separate component at high energies where we lack observations. In addition, the observed temperature is lower than that predicted by pure accretion disk models for TDEs and requires reprocessing to a constant, lower temperature. Three deep non-detections in the radio with the Very Large Array over the first two years after the event set strict limits on the production of any relativistic outflow comparable to Swift J1644+57, even if off-axis.

  3. GRB060218 AS A TIDAL DISRUPTION OF A WHITE DWARF BY AN INTERMEDIATE-MASS BLACK HOLE

    SciTech Connect (OSTI)

    Shcherbakov, Roman V.; Reynolds, Christopher S.; Pe'er, Asaf; Haas, Roland; Bode, Tanja; Laguna, Pablo

    2013-06-01

    The highly unusual pair of a gamma-ray burst (GRB) GRB060218 and an associated supernova, SN2006aj, has puzzled theorists for years. A supernova shock breakout and a jet from a newborn stellar mass compact object have been proposed to explain this pair's multiwavelength signature. Alternatively, we propose that the source is naturally explained by another channel: the tidal disruption of a white dwarf (WD) by an intermediate-mass black hole (IMBH). This tidal disruption is accompanied by a tidal pinching, which leads to the ignition of a WD and a supernova. Some debris falls back onto the IMBH, forms a disk, which quickly amplifies the magnetic field, and launches a jet. We successfully fit soft X-ray spectra with the Comptonized blackbody emission from a jet photosphere. The optical/UV emission is consistent with self-absorbed synchrotron emission from the expanding jet front. The temporal dependence of the accretion rate M-dot (t) in a tidal disruption provides a good fit to the soft X-ray light curve. The IMBH mass is found to be about 10{sup 4} M{sub Sun} in three independent estimates: (1) fitting the tidal disruption M-dot (t) to the soft X-ray light curve, (2) computing the jet base radius in a jet photospheric emission model, and (3) inferring the mass of the central black hole based on the host dwarf galaxy's stellar mass. The position of the supernova is consistent with the center of the host galaxy, while the low supernova ejecta mass is consistent with that of a WD. The high expected rate of tidal disruptions in dwarf galaxies is consistent with one source observed by the Swift satellite over several years at a distance of 150 Mpc measured for GRB060218. Encounters with WDs provide much fuel for the growth of IMBHs.

  4. Ultraviolet observations of Super-Chandrasekhar mass type Ia supernova candidates with swift UVOT

    SciTech Connect (OSTI)

    Brown, Peter J.; Smitka, Michael T.; Krisciunas, Kevin; Wang, Lifan; Kuin, Paul; De Pasquale, Massimiliano; Scalzo, Richard; Holland, Stephen; Milne, Peter

    2014-05-20

    Among Type Ia supernovae (SNe Ia), a class of overluminous objects exist whose ejecta mass is inferred to be larger than the canonical Chandrasekhar mass. We present and discuss the UV/optical photometric light curves, colors, absolute magnitudes, and spectra of three candidate Super-Chandrasekhar mass SNe—2009dc, 2011aa, and 2012dn—observed with the Swift Ultraviolet/Optical Telescope. The light curves are at the broad end for SNe Ia, with the light curves of SN 2011aa being among the broadest ever observed. We find all three to have very blue colors which may provide a means of excluding these overluminous SNe from cosmological analysis, though there is some overlap with the bluest of 'normal' SNe Ia. All three are overluminous in their UV absolute magnitudes compared to normal and broad SNe Ia, but SNe 2011aa and 2012dn are not optically overluminous compared to normal SNe Ia. The integrated luminosity curves of SNe 2011aa and 2012dn in the UVOT range (1600-6000 Å) are only half as bright as SN 2009dc, implying a smaller {sup 56}Ni yield. While it is not enough to strongly affect the bolometric flux, the early time mid-UV flux makes a significant contribution at early times. The strong spectral features in the mid-UV spectra of SNe 2009dc and 2012dn suggest a higher temperature and lower opacity to be the cause of the UV excess rather than a hot, smooth blackbody from shock interaction. Further work is needed to determine the ejecta and {sup 56}Ni masses of SNe 2011aa and 2012dn and to fully explain their high UV luminosities.

  5. THE INFLUENCE OF SUPERNOVA REMNANTS ON THE INTERSTELLAR MEDIUM IN THE LARGE MAGELLANIC CLOUD SEEN AT 20-600 μm WAVELENGTHS

    SciTech Connect (OSTI)

    Lakićević, Maša; Van Loon, Jacco Th.; Meixner, Margaret; Gordon, Karl; Roman-Duval, Julia; Seale, Jonathan; Bot, Caroline; Babler, Brian; Bolatto, Alberto; Engelbracht, Chad; Misselt, Karl; Montiel, Edward; Filipović, Miroslav; Hony, Sacha; Okumura, K.; Panuzzo, Pasquale; Sauvage, Marc; Patat, Ferdinando; Sonneborn, George; and others

    2015-01-20

    We present the analysis of supernova remnants (SNRs) in the Large Magellanic Cloud (LMC) and their influence on the environment at far-infrared (FIR) and submillimeter wavelengths. We use new observations obtained with the Herschel Space Observatory and archival data obtained with the Spitzer Space Telescope, to make the first FIR atlas of these objects. The SNRs are not clearly discernible at FIR wavelengths; however, their influence becomes apparent in maps of dust mass and dust temperature, which we constructed by fitting a modified blackbody to the observed spectral energy distribution in each sightline. Most of the dust that is seen is pre-existing interstellar dust in which SNRs leave imprints. The temperature maps clearly reveal SNRs heating surrounding dust, while the mass maps indicate the removal of 3.7{sub −2.5}{sup +7.5} M {sub ☉} of dust per SNR. This agrees with the calculations by others that significant amounts of dust are sputtered by SNRs. Under the assumption that dust is sputtered and not merely pushed away, we estimate a dust destruction rate in the LMC of 0.037{sub −0.025}{sup +0.075} M {sub ☉} yr{sup –1} due to SNRs, yielding an average lifetime for interstellar dust of 2{sub −1.3}{sup +4.0}×10{sup 7} yr. We conclude that sputtering of dust by SNRs may be an important ingredient in models of galactic evolution, that supernovae may destroy more dust than they produce, and that they therefore may not be net producers of long lived dust in galaxies.

  6. Inference on accretion flow dynamics using TCAF solution from the analysis of spectral evolution of H 1743-322 during the 2010 outburst

    SciTech Connect (OSTI)

    Mondal, Santanu; Debnath, Dipak; Chakrabarti, Sandip K. E-mail: dipak@csp.res.in

    2014-05-01

    We study accretion flow dynamics of the Galactic transient black hole candidate (BHC) H 1743-322 during its 2010 outburst by analyzing spectral data using the two-component advective flow (TCAF; Keplerian and sub-Keplerian) solution after its inclusion in XSPEC as a local model. We compare our TCAF solution fitted results with combined disk blackbody (DBB) and power-law (PL) model fitted results and find a similar smooth variation of thermal (Keplerian or DBB) and non-thermal (PL or sub-Keplerian) fluxes/rates in two types of model fits. For a spectral analysis, 2.5-25 keV spectral data from the Rossi X-Ray Timing Explorer Proportional Counter Array instrument are used. From the TCAF solution fit, accretion flow parameters, such as Keplerian rate, sub-Keplerian rate, location of centrifugal pressure-supported shock, and strength of the shock, are extracted, providing a deeper understanding of the accretion process and properties of accretion disks around BHC H 1743-322 during its X-ray outburst. Based on the halo to disk accretion rate ratio, shock properties, accretion rates, and the nature of the quasi-periodic oscillations' (if observed) entire outburst is classified into four different spectral states: hard, hard-intermediate, soft-intermediate, and soft. From the time variation of intrinsic flow parameters, it appears that their evolutions in the declining phase do not retrace the path of the rising phase. Since our current model does not include magnetic fields, spectral turnover at energies beyond 500-600 keV cannot be explained.

  7. PRECISE {gamma}-RAY TIMING AND RADIO OBSERVATIONS OF 17 FERMI {gamma}-RAY PULSARS

    SciTech Connect (OSTI)

    Ray, P. S.; Wolff, M. T.; Grove, J. E.; Gwon, C.; Kerr, M.; Parent, D.; Makeev, A.; Abdo, A. A.; Guillemot, L.; Freire, P. C. C.; Kramer, M.; Ransom, S. M.; Rea, N.; Roberts, M. S. E.; Camilo, F.; Dormody, M.; Harding, A. K.; Johnston, S.; Keith, M.; Michelson, P. F.

    2011-06-01

    We present precise phase-connected pulse timing solutions for 16 {gamma}-ray-selected pulsars recently discovered using the Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope plus one very faint radio pulsar (PSR J1124-5916) that is more effectively timed with the LAT. We describe the analysis techniques including a maximum likelihood method for determining pulse times of arrival from unbinned photon data. A major result of this work is improved position determinations, which are crucial for multiwavelength follow-up. For most of the pulsars, we overlay the timing localizations on X-ray images from Swift and describe the status of X-ray counterpart associations. We report glitches measured in PSRs J0007+7303, J1124-5916, and J1813-1246. We analyze a new 20 ks Chandra ACIS observation of PSR J0633+0632 that reveals an arcminute-scale X-ray nebula extending to the south of the pulsar. We were also able to precisely localize the X-ray point source counterpart to the pulsar and find a spectrum that can be described by an absorbed blackbody or neutron star atmosphere with a hard power-law component. Another Chandra ACIS image of PSR J1732-3131 reveals a faint X-ray point source at a location consistent with the timing position of the pulsar. Finally, we present a compilation of new and archival searches for radio pulsations from each of the {gamma}-ray-selected pulsars as well as a new Parkes radio observation of PSR J1124-5916 to establish the {gamma}-ray to radio phase offset.

  8. The continued optical to mid-infrared evolution of V838 Monocerotis

    SciTech Connect (OSTI)

    Loebman, S. R.; Wisniewski, J. P.; Schmidt, S. J.; Kowalski, A. F.; Barry, R. K.; Bjorkman, K. S.; Hammel, H. B.; Hawley, S. L.; Szkody, P.; Hebb, L.; Kasliwal, M. M.; Lynch, D. K.; Russell, R. W.; Sitko, M. L.

    2015-01-01

    The eruptive variable V838 Monocerotis (V838 Mon) gained notoriety in 2002 when it brightened nine magnitudes in a series of three outbursts and then rapidly evolved into an extremely cool supergiant. We present optical, near-infrared (near-IR), and mid-IR spectroscopic and photometric observations of V838 Mon obtained between 2008 and 2012 at the Apache Point Observatory 3.5 m, NASA IRTF 3 m, and Gemini South 8 m telescopes. We contemporaneously analyze the optical and IR spectroscopic properties of V838 Mon to arrive at a revised spectral type L3 supergiant and effective temperature T{sub eff}?20002200 K. Because there are no existing optical observational data for L supergiants, we speculate that V838 Mon may represent the prototype for L supergiants in this wavelength regime. We find a low level of H? emission present in the system, consistent with interaction between V838 Mon and its B3V binary; however, we cannot rule out a stellar collision as the genesis event, which could result in the observed H? activity. Based upon a two-component blackbody fit to all wavelengths of our data, we conclude that, as of 2009, a shell of ejecta surrounded V838 Mon at a radius of R=26310 AU with a temperature of T=2852 K. This result is consistent with IR interferometric observations from the same era and predictions from the Lynch et al. model of the expanding system, which provides a simple framework for understanding this complicated system.

  9. Fluorescent microthermographic imaging

    SciTech Connect (OSTI)

    Barton, D.L.

    1993-09-01

    In the early days of microelectronics, design rules and feature sizes were large enough that sub-micron spatial resolution was not needed. Infrared or IR thermal techniques were available that calculated the object`s temperature from infrared emission. There is a fundamental spatial resolution limitation dependent on the wavelengths of light being used in the image formation process. As the integrated circuit feature sizes began to shrink toward the one micron level, the limitations imposed on IR thermal systems became more pronounced. Something else was needed to overcome this limitation. Liquid crystals have been used with great success, but they lack the temperature measurement capabilities of other techniques. The fluorescent microthermographic imaging technique (FMI) was developed to meet this need. This technique offers better than 0.01{degrees}C temperature resolution and is diffraction limited to 0.3 {mu}m spatial resolution. While the temperature resolution is comparable to that available on IR systems, the spatial resolution is much better. The FMI technique provides better spatial resolution by using a temperature dependent fluorescent film that emits light at 612 nm instead of the 1.5 {mu}m to 12 {mu}m range used by IR techniques. This tutorial starts with a review of blackbody radiation physics, the process by which all heated objects emit radiation to their surroundings, in order to understand the sources of information that are available to characterize an object`s surface temperature. The processes used in infrared thermal imaging are then detailed to point out the limitations of the technique but also to contrast it with the FMI process. The FMI technique is then described in detail, starting with the fluorescent film physics and ending with a series of examples of past applications of FMI.

  10. A COOL DUST FACTORY IN THE CRAB NEBULA: A HERSCHEL STUDY OF THE FILAMENTS

    SciTech Connect (OSTI)

    Gomez, H. L.; Clark, C. J. R.; Gomez, E. L.; Gear, W. K. [School of Physics and Astronomy, Cardiff University, The Parade, Cardiff CF24 3AA (United Kingdom); Krause, O.; Besel, M.-A.; Bouwman, J.; Henning, Th. [Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, D-69117 Heidelberg (Germany); Barlow, M. J.; Swinyard, B. M.; Owen, P. J.; Matsuura, M. [Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom); Rho, J. [SOFIA Science Center, Universities Space Research Association, NASA Ames Research Center, MS 232, Moffett Field, CA 94035 (United States); Ivison, R. J.; Sibthorpe, B. [UK Astronomy Technology Centre, Royal Observatory Edinburgh, Blackford Hill, Edinburgh EH9 3HJ (United Kingdom); Polehampton, E. T. [Space Science and Technology Department, Rutherford Appleton Laboratory, Oxfordshire, OX11 0QX (United Kingdom)

    2012-11-20

    Whether supernovae are major sources of dust in galaxies is a long-standing debate. We present infrared and submillimeter photometry and spectroscopy from the Herschel Space Observatory of the Crab Nebula between 51 and 670 {mu}m as part of the Mass Loss from Evolved StarS program. We compare the emission detected with Herschel with multiwavelength data including millimeter, radio, mid-infrared, and archive optical images. We carefully remove the synchrotron component using the Herschel and Planck fluxes measured in the same epoch. The contribution from line emission is removed using Herschel spectroscopy combined with Infrared Space Observatory archive data. Several forbidden lines of carbon, oxygen, and nitrogen are detected where multiple velocity components are resolved, deduced to be from the nitrogen-depleted, carbon-rich ejecta. No spectral lines are detected in the SPIRE wavebands; in the PACS bands, the line contribution is 5% and 10% at 70 and 100 {mu}m and negligible at 160 {mu}m. After subtracting the synchrotron and line emission, the remaining far-infrared continuum can be fit with two dust components. Assuming standard interstellar silicates, the mass of the cooler component is 0.24{sup +0.32} {sub -0.08} M {sub Sun} for T = 28.1{sup +5.5} {sub -3.2} K. Amorphous carbon grains require 0.11 {+-} 0.01 M {sub Sun} of dust with T = 33.8{sup +2.3} {sub -1.8} K. A single temperature modified blackbody with 0.14 M {sub Sun} and 0.08 M {sub Sun} for silicate and carbon dust, respectively, provides an adequate fit to the far-infrared region of the spectral energy distribution but is a poor fit at 24-500 {mu}m. The Crab Nebula has condensed most of the relevant refractory elements into dust, suggesting the formation of dust in core-collapse supernova ejecta is efficient.

  11. EFFECT OF A HIGH OPACITY ON THE LIGHT CURVES OF RADIOACTIVELY POWERED TRANSIENTS FROM COMPACT OBJECT MERGERS

    SciTech Connect (OSTI)

    Barnes, Jennifer; Kasen, Daniel [Departments of Physics and Astronomy, 366 LeConte Hall, University of California, Berkeley, CA 94720 (United States)

    2013-09-20

    The coalescence of compact objects is a promising astrophysical source of detectable gravitational wave signals. The ejection of r-process material from such mergers may lead to a radioactively powered electromagnetic counterpart signal which, if discovered, would enhance the science returns. As very little is known about the optical properties of heavy r-process elements, previous light-curve models have adopted opacities similar to those of iron group elements. Here we consider the effect of heavier elements, particularly the lanthanides, which increase the ejecta opacity by several orders of magnitude. We include these higher opacities in time-dependent, multi-wavelength radiative transport calculations to predict the broadband light curves of one-dimensional models over a range of parameters (ejecta masses {approx}10{sup -3}-10{sup -1} M{sub Sun} and velocities {approx}0.1-0.3 c). We find that the higher opacities lead to much longer duration light curves which can last a week or more. The emission is shifted toward the infrared bands due to strong optical line blanketing, and the colors at later times are representative of a blackbody near the recombination temperature of the lanthanides (T {approx} 2500 K). We further consider the case in which a second mass outflow, composed of {sup 56}Ni, is ejected from a disk wind, and show that the net result is a distinctive two component spectral energy distribution, with a bright optical peak due to {sup 56}Ni and an infrared peak due to r-process ejecta. We briefly consider the prospects for detection and identification of these transients.

  12. Low energy spectral index and E{sub p} evolution of quasi-thermal photosphere emission of gamma-ray bursts

    SciTech Connect (OSTI)

    Deng, Wei; Zhang, Bing E-mail: zhang@physics.unlv.edu

    2014-04-20

    Recent observations by the Fermi satellite suggest that a photosphere emission component is contributing to the observed spectrum of many gamma-ray bursts (GRBs). One important question is whether the photosphere component can interpret the typical 'Band' function of GRBs with a typical low energy photon spectral index α ∼ –1. We perform a detailed study of the photosphere emission spectrum by progressively introducing several physical ingredients previously not fully incorporated, including the probability distribution of the location of a dynamically evolving photosphere, superposition of emission from an equal arrival time 'volume' in a continuous wind, the evolution of optical depth of a wind with finite but evolving outer boundary, as well as the effect of different top-hat wind luminosity (L{sub w} ) profiles. By assuming a comoving blackbody spectrum emerging from the photosphere, we find that for an outflow with a constant or increasing L{sub w} , the low-energy spectrum below the peak energy (E{sub p} ), can be modified to F {sub ν} ∼ ν{sup 1.5} (α ∼ +0.5). A softer (–1 < α < +0.5) or flat (α = –1) spectrum can be obtained during the L{sub w} decreasing phase or high-latitude-emission-dominated phase. We also study the evolution of E{sub p} as a function of wind and photosphere luminosity in this photosphere model. An E{sub p} – L tracking pattern can be reproduced if a certain positive dependence between the dimensionless entropy η and L{sub w} is introduced. However, the hard-to-soft evolution pattern cannot be reproduced unless a contrived condition is invoked. In order to interpret the Band spectrum, a more complicated photosphere model or a different energy dissipation and radiation mechanism is needed.

  13. REGULATION OF THE SPECTRAL PEAK IN GAMMA-RAY BURSTS

    SciTech Connect (OSTI)

    Beloborodov, Andrei M.

    2013-02-20

    Observations indicate that the peak of a gamma-ray burst spectrum forms in the opaque region of an ultrarelativistic jet. Recent radiative transfer calculations support this picture and show that the spectral peak is inherited from initially thermal radiation, which is changed by heating into a broad photon distribution with a high-energy tail. We discuss the processes that regulate the observed position of the spectral peak E {sub pk}. The opaque jet has three radial zones: (1) the Planck zone r < R {sub P} where a blackbody spectrum is enforced; this zone ends where the Thomson optical depth decreases to {tau} Almost-Equal-To 10{sup 5}, (2) the Wien zone R {sub P} < r < R {sub W} with a Kompaneets parameter y >> 1 where radiation has a Bose-Einstein spectrum, and (3) the Comptonization zone r > R {sub W} where the radiation spectrum develops a high-energy tail. Besides the initial jet temperature, an important factor regulating E {sub pk} is internal dissipation (of bulk motions and magnetic energy) at large distances from the central engine. Dissipation in the Planck zone reduces E {sub pk}, and dissipation in the Wien zone can increase E {sub pk}. In jets with subdominant magnetic fields, the predicted E {sub pk} varies around 1 MeV up to a maximum value of about 10 MeV. If the jet carries an energetically important magnetic field, E {sub pk} can be additionally increased by dissipation of magnetic energy. This increase is suggested by observations, which show E {sub pk} up to about 20 MeV. We also consider magnetically dominated jets; then a simple model of magnetic dissipation gives E {sub pk} Almost-Equal-To 30 {Gamma}{sub W} keV where {Gamma}{sub W} is the jet Lorentz factor at the Wien radius R {sub W}.

  14. Energy-dependent evolution in IC10 X-1: hard evidence for an extended corona and implications

    SciTech Connect (OSTI)

    Barnard, R.; Steiner, J. F.; Prestwich, A. F.; Stevens, I. R.; Clark, J. S.; Kolb, U. C.

    2014-09-10

    We have analyzed a ∼130 ks XMM-Newton observation of the dynamically confirmed black hole + Wolf-Rayet (BH+WR) X-ray binary (XB) IC10 X-1, covering ∼1 orbital cycle. This system experiences periodic intensity dips every ∼35 hr. We find that energy-independent evolution is rejected at a >5σ level. The spectral and timing evolution of IC10 X-1 are best explained by a compact disk blackbody and an extended Comptonized component, where the thermal component is completely absorbed and the Comptonized component is partially covered during the dip. We consider three possibilities for the absorber: cold material in the outer accretion disk, as is well documented for Galactic neutron star (NS) XBs at high inclination; a stream of stellar wind that is enhanced by traveling through the L1 point; and a spherical wind. We estimated the corona radius (r {sub ADC}) for IC10 X-1 from the dip ingress to be ∼10{sup 6} km, assuming absorption from the outer disk, and found it to be consistent with the relation between r {sub ADC} and 1-30 keV luminosity observed in Galactic NS XBs that spans two orders of magnitude. For the other two scenarios, the corona would be larger. Prior BH mass (M {sub BH}) estimates range over 23-38 M {sub ☉}, depending on the inclination and WR mass. For disk absorption, the inclination, i, is likely to be ∼60-80°, with M {sub BH} ∼ 24-41 M {sub ☉}. Alternatively, the L1-enhanced wind requires i ∼ 80°, suggesting ∼24-33 M {sub ☉}. For a spherical absorber, i ∼ 40°, and M {sub BH} ∼ 50-65 M {sub ☉}.

  15. NuSTAR DISCOVERY OF A CYCLOTRON LINE IN KS 1947+300

    SciTech Connect (OSTI)

    Fürst, Felix; Bellm, Eric; Harrison, Fiona; Walton, Dominic J.; Pottschmidt, Katja; Wilms, Jörn; Kennea, Jamie; Bachetti, Matteo; Boggs, Steven E.; Craig, William W.; Tomsick, John A.; Chakrabarty, Deepto; Christensen, Finn E.; Hailey, Charles J.; Stern, Daniel; Zhang, William

    2014-04-01

    We present a spectral analysis of three simultaneous Nuclear Spectroscopy Telescope Array and Swift/XRT observations of the transient Be-neutron star binary KS 1947+300 taken during its outburst in 2013/2014. These broadband observations were supported by Swift/XRT monitoring snapshots every three days, which we use to study the evolution of the spectrum over the outburst. We find strong changes of the power-law photon index, which shows a weak trend of softening with increasing X-ray flux. The neutron star shows very strong pulsations with a period of P ≈ 18.8 s. The 0.8-79 keV broadband spectrum can be described by a power law with an exponential cutoff and a blackbody component at low energies. During the second observation we detect a cyclotron resonant scattering feature at 12.5 keV, which is absent in the phase-averaged spectra of observations 1 and 3. Pulse phase-resolved spectroscopy reveals that the strength of the feature changes strongly with pulse phase and is most prominent during the broad minimum of the pulse profile. At the same phases the line also becomes visible in the first and third observation at the same energy. This discovery implies that KS 1947+300 has a magnetic field strength of B ≈ 1.1 × 10{sup 12}(1 + z) G, which is at the lower end of known cyclotron line sources.

  16. Photosphere emission in the X-ray flares of swift gamma-ray bursts and implications for the fireball properties

    SciTech Connect (OSTI)

    Peng, Fang-Kun; Liang, En-Wei; Xi, Shao-Qiang; Lu, Rui-Jing; Zhang, Bing [Guangxi Key Laboratory for Relativistic Astrophysics, the Department of Physics, Guangxi University, Nanning 530004 (China); Wang, Xiang-Yu [School of Astronomy and Space Science, Nanjing University, Nanjing 210093 (China); Hou, Shu-Jin [Institute of Physics and Electronic Engineering, Nanyang Normal College, Nanyang 473061 (China); Zhang, Jin, E-mail: lew@gxu.edu.cn, E-mail: xywang@nju.edu.cn, E-mail: zhang@physics.unlv.edu [National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China)

    2014-11-10

    X-ray flares of gamma-ray bursts (GRBs) are usually observed in the soft X-ray range and the spectral coverage is limited. In this paper, we present an analysis of 32 GRB X-ray flares that are simultaneously observed by both Burst Alert Telescope and X-Ray Telescope on board the Swift mission, so that a joint spectral analysis with a wider spectral coverage is possible. Our results show that the joint spectra of 19 flares are fitted with the absorbed single power law or the Band function models. More interestingly, the joint spectra of the other 13 X-ray flares are fitted with the absorbed single power-law model plus a blackbody component. Phenomenally, the observed spectra of these 13 flares are analogous to several GRBs with a thermal component, but only with a much lower temperature of kT = 1 ? 3 keV. Assuming that the thermal emission is the photosphere emission of the GRB fireball, we derive the fireball properties of the 13 flares that have redshift measurements, such as the bulk Lorentz factor ?{sub ph} of the outflow. The derived ?{sub ph} range from 50 to 150 and a relation of ?{sub ph} to the thermal emission luminosity is found. It is consistent with the ?{sub 0} L {sub iso} relations that are derived for the prompt gamma-ray emission. We discuss the physical implications of these results within the content of jet composition and the radiation mechanism of GRBs and X-ray flares.

  17. SGR J1550-5418 BURSTS DETECTED WITH THE FERMI GAMMA-RAY BURST MONITOR DURING ITS MOST PROLIFIC ACTIVITY

    SciTech Connect (OSTI)

    Van der Horst, A. J.; Finger, M. H. [Universities Space Research Association, NSSTC, Huntsville, AL 35805 (United States); Kouveliotou, C. [Space Science Office, VP62, NASA/Marshall Space Flight Center, Huntsville, AL 35812 (United States); Gorgone, N. M. [Connecticut College, New London, CT 06320 (United States); Kaneko, Y.; Goegues, E.; Lin, L. [Sabanc Latin-Small-Letter-Dotless-I University, Orhanl Latin-Small-Letter-Dotless-I -Tuzla, Istanbul 34956 (Turkey); Baring, M. G. [Department of Physics and Astronomy, Rice University, MS-108, P.O. Box 1892, Houston, TX 77251 (United States); Guiriec, S.; Bhat, P. N.; Chaplin, V. L.; Goldstein, A. [University of Alabama, Huntsville, CSPAR, Huntsville, AL 35805 (United States); Granot, J. [Racah Institute of Physics, Hebrew University, Jerusalem 91904 (Israel); Watts, A. L. [Astronomical Institute 'Anton Pannekoek', University of Amsterdam, Postbus 94249, 1090 GE Amsterdam (Netherlands); Bissaldi, E.; Gruber, D. [Max Planck Institute for Extraterrestrial Physics, Giessenbachstrasse, Postfach 1312, 85748 Garching (Germany); Gehrels, N.; Harding, A. K. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Gibby, M. H.; Giles, M. M., E-mail: A.J.VanDerHorst@uva.nl [Jacobs Technology, Inc., Huntsville, AL (United States); and others

    2012-04-20

    We have performed detailed temporal and time-integrated spectral analysis of 286 bursts from SGR J1550-5418 detected with the Fermi Gamma-ray Burst Monitor (GBM) in 2009 January, resulting in the largest uniform sample of temporal and spectral properties of SGR J1550-5418 bursts. We have used the combination of broadband and high time-resolution data provided with GBM to perform statistical studies for the source properties. We determine the durations, emission times, duty cycles, and rise times for all bursts, and find that they are typical of SGR bursts. We explore various models in our spectral analysis, and conclude that the spectra of SGR J1550-5418 bursts in the 8-200 keV band are equally well described by optically thin thermal bremsstrahlung (OTTB), a power law (PL) with an exponential cutoff (Comptonized model), and two blackbody (BB) functions (BB+BB). In the spectral fits with the Comptonized model, we find a mean PL index of -0.92, close to the OTTB index of -1. We show that there is an anti-correlation between the Comptonized E{sub peak} and the burst fluence and average flux. For the BB+BB fits, we find that the fluences and emission areas of the two BB functions are correlated. The low-temperature BB has an emission area comparable to the neutron star surface area, independent of the temperature, while the high-temperature BB has a much smaller area and shows an anti-correlation between emission area and temperature. We compare the properties of these bursts with bursts observed from other SGR sources during extreme activations, and discuss the implications of our results in the context of magnetar burst models.

  18. A LINGERING NON-THERMAL COMPONENT IN THE GAMMA-RAY BURST PROMPT EMISSION: PREDICTING GeV EMISSION FROM THE MeV SPECTRUM

    SciTech Connect (OSTI)

    Basak, Rupal; Rao, A. R., E-mail: rupalb@tifr.res.in, E-mail: arrao@tifr.res.in [Tata Institute of Fundamental Research, Mumbai 400005 (India)

    2013-09-20

    The high-energy GeV emission of gamma-ray bursts (GRBs) detected by Fermi/LAT has a significantly different morphology compared to the lower energy MeV emission detected by Fermi/GBM. Though the late-time GeV emission is believed to be synchrotron radiation produced via an external shock, this emission as early as the prompt phase is puzzling. A meaningful connection between these two emissions can be drawn only by an accurate description of the prompt MeV spectrum. We perform a time-resolved spectroscopy of the Gamma-ray Burst Monitor (GBM) data of long GRBs with significant GeV emission, using a model consisting of two blackbodies and a power law. We examine in detail the evolution of the spectral components and find that GRBs with high GeV emission (GRB 090902B and GRB 090926A) have a delayed onset of the power-law component in the GBM spectrum, which lingers at the later part of the prompt emission. This behavior mimics the flux evolution in the Large Area Telescope (LAT). In contrast, bright GBM GRBs with an order of magnitude lower GeV emission (GRB 100724B and GRB 091003) show a coupled variability of the total and the power-law flux. Further, by analyzing the data for a set of 17 GRBs, we find a strong correlation between the power-law fluence in the MeV and the LAT fluence (Pearson correlation: r = 0.88 and Spearman correlation: ? = 0.81). We demonstrate that this correlation is not influenced by the correlation between the total and the power-law fluences at a confidence level of 2.3?. We speculate the possible radiation mechanisms responsible for the correlation.

  19. HUBBLE SPACE TELESCOPE FAR ULTRAVIOLET SPECTROSCOPY OF THE RECURRENT NOVA T PYXIDIS

    SciTech Connect (OSTI)

    Godon, Patrick; Sion, Edward M. [Astronomy and Astrophysics, Villanova University, Villanova, PA 19085 (United States); Starrfield, Sumner [School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85287 (United States); Livio, Mario; Williams, Robert E. [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Woodward, Charles E. [Minnesota Institute for Astrophysics, University of Minnesota, Minneapolis, MN 55455 (United States); Kuin, Paul [Mullard Space Science Laboratory, University College London, Holmbury St. Mary, Dorking, Surrey RH5 6NT (United Kingdom); Page, Kim L., E-mail: patrick.godon@villanova.edu, E-mail: edward.sion@villanova.edu, E-mail: sumner.starrfield@asu.edu, E-mail: mlivio@stsci.edu, E-mail: wms@stsci.edu, E-mail: chelsea@astro.umn.edu, E-mail: n.kuin@ucl.ac.uk, E-mail: klp5@leicester.ac.uk [Department of Physics and Astronomy, University of Leicester, Leicester, LE1 7RH (United Kingdom)

    2014-04-01

    With six recorded nova outbursts, the prototypical recurrent nova T Pyxidis (T Pyx) is the ideal cataclysmic variable system to assess the net change of the white dwarf mass within a nova cycle. Recent estimates of the mass ejected in the 2011 outburst ranged from a few ?10{sup 5} M {sub ?} to 3.3 10{sup 4} M {sub ?}, and assuming a mass accretion rate of 10{sup 8}-10{sup 7} M {sub ?}yr{sup 1} for 44yr, it has been concluded that the white dwarf in T Pyx is actually losing mass. Using NLTE disk modeling spectra to fit our recently obtained Hubble Space Telescope COS and STIS spectra, we find a mass accretion rate of up to two orders of magnitude larger than previously estimated. Our larger mass accretion rate is due mainly to the newly derived distance of T Pyx (4.8kpc, larger than the previous 3.5kpc estimate), our derived reddening of E(B V) = 0.35 (based on combined IUE and GALEX spectra), and NLTE disk modeling (compared to blackbody and raw flux estimates in earlier works). We find that for most values of the reddening (0.25 ? E(B V) ? 0.50) and white dwarf mass (0.70 M {sub ?} ? M {sub wd} ? 1.35 M {sub ?}) the accreted mass is larger than the ejected mass. Only for a low reddening (?0.25 and smaller) combined with a large white dwarf mass (0.9 M {sub ?} and larger) is the ejected mass larger than the accreted one. However, the best results are obtained for a larger value of reddening.

  20. Draft report on melt point as a function of composition for urania-based systems

    SciTech Connect (OSTI)

    Valdez, James A; Byler, Darrin D

    2012-06-08

    This report documents the testing of a urania (UO{sub 2.00}) sample as a baseline and the attempt to determine the melt point associated with 4 compositions of urania-ceria and urania-neodymia pseudo binaries provided by ORNL, with compositions of 95/5, and 80/20 and of (U/Ce)O{sub 2.00} and (U/Nd)O{sub 2.00} in the newly developed ceramic melt point determination system. A redesign of the system using parts fabricated from tungsten was undertaken in order to help prevent contamination and tungsten carbide formation in the crucibles. The previously developed system employed mostly graphite parts that were shown to react with the sample containment black-body crucible leading to unstable temperature readings and crucible failure, thus the redesign. Measured melt point values of UO{sub 2.00} and U{sub 0.95}Ce{sub 0.05}O{sub 2.00}, U{sub 0.80}Ce{sub 0.20}O{sub 2.00}, U{sub 0.95}Nd{sub 0.05}O{sub 2.00} and U{sub 0.80}Nd{sub 0.20}O{sub 2.00} were measured using a 2-color pyrometer. The value measured for UO{sub 2.00} was consistent with the published accepted value 2845 C {+-} 25 C, although a wide range of values has been published by researchers and will be discussed later in the text. For comparison, values obtained from a published binary phase diagram of UO{sub 2}-Nd{sub 2}O{sub 3} were used for comparison with our measure values. No literature melt point values for comparison with the measurements performed in this study were found for (U/Ce)O{sub 2.00} in our stoichiometry range.

  1. Investigating the presence of 500 μm submillimeter excess emission in local star forming galaxies

    SciTech Connect (OSTI)

    Kirkpatrick, Allison; Calzetti, Daniela; Galametz, Maud; Kennicutt, Rob Jr.; Dale, Daniel; Aniano, Gonzalo; Sandstrom, Karin; Walter, Fabian; Armus, Lee; Crocker, Alison; Hinz, Joannah; Hunt, Leslie; Koda, Jin

    2013-11-20

    Submillimeter excess emission has been reported at 500 μm in a handful of local galaxies, and previous studies suggest that it could be correlated with metal abundance. We investigate the presence of an excess submillimeter emission at 500 μm for a sample of 20 galaxies from the Key Insights on Nearby Galaxies: a Far Infrared Survey with Herschel (KINGFISH) that span a range of morphologies and metallicities (12 + log (O/H) = 7.8-8.7). We probe the far-infrared (IR) emission using images from the Spitzer Space Telescope and Herschel Space Observatory in the wavelength range 24-500 μm. We model the far-IR peak of the dust emission with a two-temperature modified blackbody and measure excess of the 500 μm photometry relative to that predicted by our model. We compare the submillimeter excess, where present, with global galaxy metallicity and, where available, resolved metallicity measurements. We do not find any correlation between the 500 μm excess and metallicity. A few individual sources do show excess (10%-20%) at 500 μm; conversely, for other sources, the model overpredicts the measured 500 μm flux density by as much as 20%, creating a 500 μm 'deficit'. None of our sources has an excess larger than the calculated 1σ uncertainty, leading us to conclude that there is no substantial excess at submillimeter wavelengths at or shorter than 500 μm in our sample. Our results differ from previous studies detecting 500 μm excess in KINGFISH galaxies largely due to new, improved photometry used in this study.

  2. SWIFT DISCOVERY OF A NEW SOFT GAMMA REPEATER, SGR J1745-29, NEAR SAGITTARIUS A*

    SciTech Connect (OSTI)

    Kennea, J. A.; Burrows, D. N.; Kouveliotou, C.; Goegues, E.; Kaneko, Y.; Evans, P. A.; Degenaar, N.; Reynolds, M. T.; Miller, J. M.; Wijnands, R.; Mori, K.; Gehrels, N.

    2013-06-20

    Starting in 2013 February, Swift has been performing short daily monitoring observations of the G2 gas cloud near Sgr A* with the X-Ray Telescope to determine whether the cloud interaction leads to an increase in the flux from the Galactic center. On 2013 April 24 Swift detected an order of magnitude rise in the X-ray flux from the region near Sgr A*. Initially thought to be a flare from Sgr A*, the detection of a short hard X-ray burst from the same region by the Burst Alert Telescope suggested that the flare was from an unresolved new Soft Gamma Repeater, SGR J1745-29. Here we present the discovery of SGR J1745-29 by Swift, including analysis of data before, during, and after the burst. We find that the spectrum in the 0.3-10 keV range is well fit by an absorbed blackbody model with kT{sub BB} {approx_equal} 1 keV and absorption consistent with previously measured values from the quiescent emission from Sgr A*, strongly suggesting that this source is at a similar distance. Only one SGR burst has been detected so far from the new source, and the persistent light curve shows little evidence of decay in approximately two weeks of monitoring after outburst. We discuss this light curve trend and compare it with those of other well covered SGR outbursts. We suggest that SGR J1745-29 belongs to an emerging subclass of magnetars characterized by low burst rates and prolonged steady X-ray emission one to two weeks after outburst onset.

  3. A 0.8-2.4 ?m Transmission spectrum of the hot Jupiter CoRoT-1b

    SciTech Connect (OSTI)

    Schlawin, E.; Herter, T.; Zhao, M.; Teske, J. K.

    2014-03-01

    Hot Jupiters with brightness temperatures ?2000 K can have TiO and VO molecules as gaseous species in their atmospheres. The TiO and VO molecules can potentially induce temperature inversions in hot Jupiter atmospheres and also have an observable signature of large optical to infrared transit depth ratios. Previous transmission spectra of very hot Jupiters have shown a lack of TiO and VO, but only in planets that also appear to lack temperature inversions. We measure the transmission spectrum of CoRoT-1b, a hot Jupiter that was predicted to have a temperature inversion potentially due to significant TiO and VO in its atmosphere. We employ the multi-object spectroscopy method using the SpeX and MORIS instruments on the Infrared Telescope Facility (IRTF) and the Gaussian process method to model red noise. By using a simultaneous reference star on the slit for calibration and a wide slit to minimize slit losses, we achieve transit depth precision of 0.03%-0.09%, comparable to the atmospheric scale height but detect no statistically significant molecular features. We combine our IRTF data with optical CoRoT transmission measurements to search for differences in the optical and near-infrared absorption that would arise from TiO/VO. Our IRTF spectrum and the CoRoT photometry disfavor a TiO/VO-rich spectrum for CoRoT-1b, suggesting that the atmosphere has another absorber that could create a temperature inversion or that the blackbody-like emission from the planet is due to a spectroscopically flat cloud, dust, or haze layer that smoothes out molecular features in both CoRoT-1b's emission and transmission spectra. This system represents the faintest planet hosting star (K = 12.2) with a measured planetary transmission spectrum.

  4. 13th TOPICAL CONFERENCE ON HIGH TEMPERATURE PLASMA DIAGNOSTICS SCIENTIFIC PROGRAM

    SciTech Connect (OSTI)

    C. BARNES

    2000-07-01

    Electron cyclotron emission (ECE) has been employed as a standard electron temperature profile diagnostic on many tokamaks and stellarators, but most magnetically confined plasma devices cannot take advantage of standard ECE diagnostics to measure temperature. They are either overdense, operating at high density relative to the magnetic field (e.g. {omega}{sub pe} >> {Omega}{sub ce} in a spherical torus) or they have insufficient density and temperature to reach the blackbody condition ({tau} > 2). Electron Bernstein waves (EBWs) are electrostatic waves which can propagate in overdense plasmas and have a high optical thickness at the electron cyclotron resonance layers, as a result of their large K{sub i}. This talk reports on measurements of EBW emission on the CDX-U spherical torus, where B{sub 0} {approx} 2 kG, {approx} 10{sup 13} cm{sup -3} and T{sub e} {approx} 10 - 200 eV. Results will be presented for both direct detection of EBWs and for mode-converted EBW emission. The EBW emission was absolutely calibrated and compared to the electron temperature profile measured by a multi-point Thomson scattering diagnostic. Depending on the plasma conditions, the mode-converted EBW radiation temperature was found to be {le} T{sub e} and the emission source was determined to be radially localized at the electron cyclotron resonance layer. A Langmuir triple probe was employed to measure changes in edge density profile in the vicinity of the upper hybrid resonance where the mode conversion of the EBWs is expected to occur. Changes in the mode conversion efficiency may explain the observation of mode-converted EBW radiation temperatures below T{sub e}. Initial results suggest EBW emission and EBW heating are viable concepts for plasmas where {omega}{sub pe} >> {Omega}{sub ce}.

  5. Hot electromagnetic outflows. III. Displaced fireball in a strong magnetic field

    SciTech Connect (OSTI)

    Thompson, Christopher; Gill, Ramandeep

    2014-08-10

    The evolution of a dilute electron-positron fireball is calculated in the regime of strong magnetization and high compactness (ℓ ∼ 10{sup 3}-10{sup 8}). Heating is applied at a low effective temperature (<25 keV), appropriate to breakout from a confining medium, so that relaxation to a blackbody is inhibited by pair annihilation. The diffusion equation for Compton scattering by thermal pairs is coupled to a trans-relativistic cyclo-synchrotron source. We find that the photon spectrum develops a quasi-thermal peak at energy ∼0.1 m{sub e}c {sup 2} in the comoving frame, with a power-law slope below it that is characteristic of gamma-ray bursts (GRBs; F{sub ω} ∼ const). The formation of a thermal high-energy spectrum is checked using the full kinetic equations. Calculations for a baryon-dominated photosphere reveal a lower spectral peak energy, and a harder low-energy spectrum, unless ion rest mass carries ≲ 10{sup –5} of the energy flux. We infer that (1) the GRB spectrum is inconsistent with the neutron-rich wind emitted by a young magnetar or neutron torus, and points to an event horizon in the engine; (2) neutrons play a negligible role in prompt gamma-ray emission; (3) the relation between observed peak frequency and burst energy is bounded below by the observed Amati relation if the Lorentz factor ∼(opening angle){sup –1} at breakout, and the jet is surrounded by a broader sheath that interacts with a collapsing stellar core; (4) X-ray flashes are consistent with magnetized jets with ion-dominated photospheres; (5) high-frequency Alfvén waves may become charge starved in the dilute pair gas; (6) limitations on magnetic reconnection from plasma collisionality have been overestimated.

  6. Radiation feedback in ULIRGs: are photons movers and shakers?

    SciTech Connect (OSTI)

    Davis, Shane W.; Murray, Norman; Jiang, Yan-Fei; Stone, James M.

    2014-12-01

    We perform multidimensional radiation hydrodynamics simulations to study the impact of radiation forces on atmospheres composed of dust and gas. Our setup closely follows that of Krumholz and Thompson, assuming that dust and gas are well-coupled and that the radiation field is characterized by blackbodies with temperatures ≳ 80 K, as might be found in ultraluminous infrared galaxies (ULIRGs). In agreement with previous work, we find that Rayleigh-Taylor instabilities develop in radiation supported atmospheres, leading to inhomogeneities that limit momentum exchange between radiation and dusty gas, and eventually providing a near balance of the radiation and gravitational forces. However, the evolution of the velocity and spatial distributions of the gas differs significantly from previous work, which utilized a less accurate flux-limited diffusion (FLD) method. Our variable Eddington tensor simulations show continuous net acceleration of the gas and never reach a steady state. In contrast, our FLD results show little net acceleration of the gas and settle into a quasi-steady, turbulent state with low velocity dispersion. The discrepancies result primarily from the inability of FLD to properly model the variation of the radiation field around structures that are less than a few optical depths across. We consider the effect of varying the optical depth and study the differences between two-dimensional and three-dimensional runs. We conclude that radiation feedback remains a plausible mechanism for driving high-Mach number turbulence in ULIRGs with sufficiently high optical depths. We discuss implications for observed systems and galactic-scale numerical simulations of feedback.

  7. Environmental assessment for the satellite power system concept development and evaluation program-electromagnetic systems compatibility

    SciTech Connect (OSTI)

    Davis, K A; Grant, W B; Morrison, E L; Juroshek, J R

    1981-01-01

    The EMC analysis addressed only the direct effects of electromagnetic emissions from the SPS on other technological systems. Emissions were defined quite broadly, including not only those from the microwave system, but also thermal blackbody emission and scattered sunlight from the satellite. The analysis is based on the design for an SPS as described in the Reference System Report and some quantitative conclusions, e.g., ranges from rectenna sites at which effects are expected are specific to that design. The methodology and qualitative conclusions, however, apply to an SPS concept using microwave power transmission. Quantitative conclusions have been obtained parametrically and can be adjusted as SPS designs change. The electromagnetic environment that the Reference System would produce, and in which other systems would have to function, is described. As an early part of the EMC Assessment, the problems expected for a hypothetical rectenna site, in the Mojave Desert of southern California, were analyzed in detail. This effort provided an initial quantitative indication of the scope of potential EMC problems and indicated the importance of EMC considerations in rectenna site selection. The results of this analysis are presented. The effects of SPS microwave emissions on important categories of electronic systems and equipment are summarized, with many examples of test results and demonstrated techniques for mitigation of problems encountered. SPS effects on other satellite systems are presented. Astronomical research frequently involves measurement of extremely low levels of electromagnetic radiation and is thus very susceptible to interference. The concerns of both radio astronomy with microwave emissions from SPS and optical astronomy with sunlight scattered from SPS spacecraft are discussed. Summaries of mitigation techniques, cost estimates, and conclusions are presented. (WHK)

  8. A reconsideration of the noise equivalent power and the data analysis procedure for the infrared imaging video bolometers

    SciTech Connect (OSTI)

    Pandya, Shwetang N. Sano, Ryuichi; Peterson, Byron J.; Kobayashi, Masahiro; Mukai, Kiyofumi; Pandya, Santosh P.

    2014-12-15

    The infrared imaging video bolometer (IRVB) used for measurement of the two-dimensional (2D) radiation profiles from the Large Helical Device has been significantly upgraded recently to improve its signal to noise ratio, sensitivity, and calibration, which ultimately provides quantitative measurements of the radiation from the plasma. The reliability of the quantified data needs to be established by various checks. The noise estimates also need to be revised and more realistic values need to be established. It is shown that the 2D heat diffusion equation can be used for estimating the power falling on the IRVB foil, even with a significant amount of spatial variation in the thermal diffusivity across the area of the platinum foil found experimentally during foil calibration. The equation for the noise equivalent power density (NEPD) is re-derived to include the errors in the measurement of the thermophysical and the optical properties of the IRVB foil. The theoretical value estimated using this newly derived equation matches closely, within 5.5%, with the mean experimental value. The change in the contribution of each error term of the NEPD equation with rising foil temperature is also studied and the blackbody term is found to dominate the other terms at elevated operating temperatures. The IRVB foil is also sensitive to the charge exchange (CX) neutrals escaping from the plasma. The CX neutral contribution is estimated to be marginally higher than the noise equivalent power (NEP) of the IRVB. It is also established that the radiation measured by the IRVB originates from the impurity line radiation from the plasma and not from the heated divertor tiles. The change in the power density due to noise reduction measures such as data smoothing and averaging is found to be comparable to the IRVB NEPD. The precautions that need to be considered during background subtraction are also discussed with experimental illustrations. Finally, the analysis algorithm with all the

  9. HOT-DUST (690 K) LUMINOSITY DENSITY AND ITS EVOLUTION IN THE LAST 7.5 GYR

    SciTech Connect (OSTI)

    Messias, H.; Afonso, J. M.; Mobasher, B.

    2013-10-20

    We study the contribution of hot-dust to the luminosity density of galaxies and its evolution with cosmic time. Using the Spitzer-IRAC data over an area of 1.8 deg{sup 2} covered by the Cosmic Evolution Survey (COSMOS) field, we estimate the contribution from hot-dust at rest-frame 4.2 μm (from 0 ∼< z ∼< 0.2 up to 0.5 ∼< z ∼< 0.9). This wavelength corresponds to blackbody temperature of ∼690 K. The contribution of stellar emission is estimated from the rest-frame 1.6 μm luminosity (assumed to result from stellar emission alone) and subtracted from the mid-infrared luminosity of galaxies to measure hot-dust emission. To attempt the study of the 3.3 μm polycyclic aromatic hydrocarbon (PAH) feature, we use the rest-frame 4.2 μm to infer the hot-dust flux at 3.3 μm. This study is performed for different spectral types of galaxies: early-type, late-type, starburst, and IR-selected active galactic nuclei (AGNs). We find that (1) the decrease of the hot-dust luminosity density since 0.5 ∼< z ∼< 1 is steeper (by at least 0.5 dex) compared with that of the cold-dust, giving support to the scenario where galaxy obscuration increases with redshift, as proposed in the literature; (2) hot-dust and PAH emission evolution seems to be correlated with stellar mass, where rest-frame 1.6 μm luminous non-AGN galaxies (i.e., massive systems) show a stronger decrement (with decreasing redshift) in hot-dust and PAH emission than the less luminous (less massive) non-AGN galaxies; (3) despite comprising ∼< 3% of the total sample, AGN contribute as much as a third to the hot-dust luminosity density at z < 1 and clearly dominate the bright-end of the total hot-dust luminosity density function at 0.5 ∼< z ∼< 0.9; (4) the average dust-to-total luminosity ratio increases with redshift, while PAH-to-total luminosity ratio remains fairly constant; (5) at M{sub 1.6} > –25, the dust-to-total and PAH-to-total luminosity ratios increase with decreasing luminosity, but

  10. Characterization of the atmosphere of the hot Jupiter HAT-P-32Ab and the M-dwarf companion HAT-P-32B

    SciTech Connect (OSTI)

    Zhao, Ming; Wright, Jason T.; Curtis, Jason; O'Rourke, Joseph G.; Knutson, Heather A.; Ngo, Henry; Burrows, Adam; Fortney, Johnathan; Fulton, Benjamin J.; Baranec, Christoph; Riddle, Reed; Hinkley, Sasha; Law, Nicholas M.; Muirhead, Philip S.; Showman, Adam P.; Burruss, Rick

    2014-12-01

    We report secondary eclipse photometry of the hot Jupiter HAT-P-32Ab, taken with Hale/Wide-field Infra-Red Camera (WIRC) in H and K{sub S} bands and with Spitzer/IRAC at 3.6 and 4.5 μm. We carried out adaptive optics imaging of the planet host star HAT-P-32A and its companion HAT-P-32B in the near-IR and the visible. We clearly resolve the two stars from each other and find a separation of 2.''923 ± 0.''004 and a position angle 110.°64 ± 0.°12. We measure the flux ratios of the binary in g'r'i'z' and H and K{sub S} bands, and determine T {sub eff}= 3565 ± 82 K for the companion star, corresponding to an M1.5 dwarf. We use PHOENIX stellar atmosphere models to correct the dilution of the secondary eclipse depths of the hot Jupiter due to the presence of the M1.5 companion. We also improve the secondary eclipse photometry by accounting for the non-classical, flux-dependent nonlinearity of the WIRC IR detector in the H band. We measure planet-to-star flux ratios of 0.090% ± 0.033%, 0.178% ± 0.057%, 0.364% ± 0.016%, and 0.438% ± 0.020% in the H, K{sub S} , 3.6 and 4.5 μm bands, respectively. We compare these with planetary atmospheric models, and find they prefer an atmosphere with a temperature inversion and inefficient heat redistribution. However, we also find that the data are equally well described by a blackbody model for the planet with T {sub p} = 2042 ± 50 K. Finally, we measure a secondary eclipse timing offset of 0.3 ± 1.3 minutes from the predicted mid-eclipse time, which constrains e = 0.0072{sub −0.0064}{sup +0.0700} when combined with radial velocity data and is more consistent with a circular orbit.

  11. DISCOVERY OF AN ULTRASOFT X-RAY TRANSIENT SOURCE IN THE 2XMM CATALOG: A TIDAL DISRUPTION EVENT CANDIDATE

    SciTech Connect (OSTI)

    Lin Dacheng; Webb, Natalie A.; Barret, Didier; Carrasco, Eleazar R.; Farrell, Sean A.

    2011-09-01

    We have discovered an ultrasoft X-ray transient source, 2XMMi J184725.1-631724, which was detected serendipitously in two XMM-Newton observations in the direction of the center of the galaxy IC 4765-f01-1504 at a redshift of 0.0353. These two observations were separated by 211 days, with the 0.2-10 keV absorbed flux increasing by a factor of about nine. Their spectra are best described by a model dominated by a thermal disk or a single-temperature blackbody component (contributing {approx}>80% of the flux) plus a weak power-law component. The thermal emission has a temperature of a few tens of eV, and the weak power-law component has a photon index of {approx}3.5. Similar to the black hole X-ray binaries in the thermal state, our source exhibits an accretion disk whose luminosity appears to follow the L{proportional_to}T {sup 4} relation. This would indicate that the black hole mass is about 10{sup 5}-10{sup 6} M{sub sun} using the best-fitting inner disk radius. Both XMM-Newton observations show variability of about 21% on timescales of hours, which can be explained as due to fast variations in the mass accretion rate. The source was not detected by ROSAT in an observation in 1992, indicating a variability factor of {approx}>64 over longer timescales. The source was not detected again in X-rays in a Swift observation in 2011 February, implying a flux decrease by a factor of {approx}>12 since the last XMM-Newton observation. The transient nature, in addition to the extreme softness of the X-ray spectra and the inactivity of the galaxy implied by the lack of strong optical emission lines, makes it a candidate tidal disruption event. If this is the case, the first XMM-Newton observation would have been in the rising phase and the second one in the decay phase.

  12. OPTICAL DISCOVERY OF PROBABLE STELLAR TIDAL DISRUPTION FLARES

    SciTech Connect (OSTI)

    Van Velzen, Sjoert; Farrar, Glennys R.; Gezari, Suvi; Morrell, Nidia; Zaritsky, Dennis; Oestman, Linda; Smith, Mathew; Gelfand, Joseph; Drake, Andrew J.

    2011-11-10

    Using archival Sloan Digital Sky Survey (SDSS) multi-epoch imaging data (Stripe 82), we have searched for the tidal disruption of stars by supermassive black holes in non-active galaxies. Two candidate tidal disruption events (TDEs) are identified. The TDE flares have optical blackbody temperatures of 2 Multiplication-Sign 10{sup 4} K and observed peak luminosities of M{sub g} = -18.3 and -20.4 ({nu}L{sub {nu}} = 5 Multiplication-Sign 10{sup 42}, 4 Multiplication-Sign 10{sup 43} erg s{sup -1}, in the rest frame); their cooling rates are very low, qualitatively consistent with expectations for tidal disruption flares. The properties of the TDE candidates are examined using (1) SDSS imaging to compare them to other flares observed in the search, (2) UV emission measured by GALEX, and (3) spectra of the hosts and of one of the flares. Our pipeline excludes optically identifiable AGN hosts, and our variability monitoring over nine years provides strong evidence that these are not flares in hidden AGNs. The spectra and color evolution of the flares are unlike any SN observed to date, their strong late-time UV emission is particularly distinctive, and they are nuclear at high resolution arguing against these being first cases of a previously unobserved class of SNe or more extreme examples of known SN types. Taken together, the observed properties are difficult to reconcile with an SN or an AGN-flare explanation, although an entirely new process specific to the inner few hundred parsecs of non-active galaxies cannot be excluded. Based on our observed rate, we infer that hundreds or thousands of TDEs will be present in current and next-generation optical synoptic surveys. Using the approach outlined here, a TDE candidate sample with O(1) purity can be selected using geometric resolution and host and flare color alone, demonstrating that a campaign to create a large sample of TDEs, with immediate and detailed multi-wavelength follow-up, is feasible. A by-product of this

  13. On the efficacy of imploding plasma liners for magnetized fusion target compression

    SciTech Connect (OSTI)

    Parks, P. B.

    2008-06-15

    A new theoretical model is formulated to study the idea of merging a spherical array of converging plasma jets to form a 'plasma liner' that further converges to compress a magnetized plasma target to fusion conditions [Y. C. F. Thio et al., 'Magnetized target fusion in a spheroidal geometry with standoff drivers', Current Trends in International Fusion Research II, edited by E. Panarella (National Research Council Canada, Ottawa, Canada, 1999)]. For a spherically imploding plasma liner shell with high initial Mach number (M=liner speed/sound speed) the rise in liner density with decreasing radius r goes as {rho}{approx}1/r{sup 2}, for any constant adiabatic index {gamma}=d ln p/d ln {rho}. Accordingly, spherical convergence amplifies the ram pressure of the liner on target by the factor A{approx}C{sup 2}, indicating strong coupling to its radial convergence C=r{sub m}/R, where r{sub m}(R)=jet merging radius (compressed target radius), and A=compressed target pressure/initial liner ram pressure. Deuterium-tritium (DT) plasma liners with initial velocity {approx}100 km/s and {gamma}=5/3, need to be hypersonic M{approx}60 and thus cold in order to realize values of A{approx}10{sup 4} necessary for target ignition. For optically thick DT liners, T<2 eV, n>10{sup 19}-10{sup 20} cm{sup -3}, blackbody radiative cooling is appreciable and may counteract compressional heating during the later stages of the implosion. The fluid then behaves as if the adiabatic index were depressed below 5/3, which in turn means that the same amplification A=1.6x10{sup 4} can be accomplished with a reduced initial Mach number M{approx_equal}12.7({gamma}-0.3){sup 4.86}, valid in the range (10

  14. Superluminous supernovae as standardizable candles and high-redshift distance probes

    SciTech Connect (OSTI)

    Inserra, C.; Smartt, S. J.

    2014-12-01

    We investigate the use of type Ic superluminous supernovae (SLSN Ic) as standardizable candles and distance indicators. Their appeal as cosmological probes stems from their remarkable peak luminosities, hot blackbody temperatures, and bright rest-frame ultraviolet emission. We present a sample of 16 published SLSN, from redshifts 0.1 to 1.2, and calculate accurate K corrections to determine uniform magnitudes in 2 synthetic rest-frame filter bandpasses with central wavelengths at 400 nm and 520 nm. At 400 nm, we find an encouragingly low scatter in their uncorrected, raw mean magnitudes with M(400) = –21.86 ± 0.35 mag for the full sample of 16 objects. We investigate the correlation between their decline rates and peak magnitude and find that the brighter events appear to decline more slowly. In a manner similar to the Phillips relation for type Ia SNe (SNe Ia), we define a ΔM {sub 20} decline relation. This correlates peak magnitude and decline over 20 days and can reduce the scatter in standardized peak magnitudes to ±0.22 mag. We further show that M(400) appears to have a strong color dependence. Redder objects are fainter and also become redder faster. Using this peak magnitudecolor evolution relation, a surprisingly low scatter of between ±0.08 mag and ±0.13 mag can be found in peak magnitudes, depending on sample selection. However, we caution that only 8 to 10 objects currently have enough data to test this peak magnitudecolor evolution relation. We conclude that SLSN Ic are promising distance indicators in the high-redshift universe in regimes beyond those possible with SNe Ia. Although the empirical relationships are encouraging, the unknown progenitor systems, how they may evolve with redshift, and the uncertain explosion physics are of some concern. The two major measurement uncertainties are the limited numbers of low-redshift, well-studied objects available to test these relationships and internal dust extinction in the host galaxies.

  15. Rapidly evolving and luminous transients from Pan-STARRS1

    SciTech Connect (OSTI)

    Drout, M. R.; Chornock, R.; Soderberg, A. M.; Sanders, N. E.; McKinnon, R.; Milisavljevic, D.; Margutti, R.; Berger, E.; Calkins, M.; Fong, W.; Kirshner, R. P.; Lunnan, R. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Rest, A. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Foley, R. J. [Astronomy Department, University of Illinois at Urbana-Champaign, 1002 West Green Street, Urbana, IL 61801 (United States); Gezari, S. [Department of Astronomy, University of Maryland, College Park, MD 20742-2421 (United States); Huber, M. E. [Institute for Astronomy, University of Hawaii at Manoa, Honolulu, HI 96822 (United States); Kankare, E.; Mattila, S. [Finnish Centre for Astronomy with ESO (FINCA), University of Turku, Vislntie 20, FI-21500 Piikki (Finland); Leibler, C. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95060 (United States); Marion, G. H., E-mail: mdrout@cfa.harvard.edu [Department of Astronomy, University of Texas at Austin, Austin, TX 78712 (United States); and others

    2014-10-10

    In the past decade, several rapidly evolving transients have been discovered whose timescales and luminosities are not easily explained by traditional supernovae (SNe) models. The sample size of these objects has remained small due, at least in part, to the challenges of detecting short timescale transients with traditional survey cadences. Here we present the results from a search within the Pan-STARRS1 Medium Deep Survey (PS1-MDS) for rapidly evolving and luminous transients. We identify 10 new transients with a time above half-maximum (t {sub 1/2}) of less than 12 days and 16.5 > M > 20 mag. This increases the number of known events in this region of SN phase space by roughly a factor of three. The median redshift of the PS1-MDS sample is z = 0.275 and they all exploded in star-forming galaxies. In general, the transients possess faster rise than decline timescale and blue colors at maximum light (g {sub P1} r {sub P1} ? 0.2). Best-fit blackbodies reveal photospheric temperatures/radii that expand/cool with time and explosion spectra taken near maximum light are dominated by a blue continuum, consistent with a hot, optically thick, ejecta. We find it difficult to reconcile the short timescale, high peak luminosity (L > 10{sup 43} erg s{sup 1}), and lack of UV line blanketing observed in many of these transients with an explosion powered mainly by the radioactive decay of {sup 56}Ni. Rather, we find that many are consistent with either (1) cooling envelope emission from the explosion of a star with a low-mass extended envelope that ejected very little (<0.03 M {sub ?}) radioactive material, or (2) a shock breakout within a dense, optically thick, wind surrounding the progenitor star. After calculating the detection efficiency for objects with rapid timescales in the PS1-MDS we find a volumetric rate of 4800-8000 events yr{sup 1} Gpc{sup 3} (4%-7% of the core-collapse SN rate at z = 0.2).

  16. Time resolved spectroscopy of SGR J15505418 bursts detected with Fermi/gamma-ray burst monitor

    SciTech Connect (OSTI)

    Younes, G. [Universities Space Research Association, 6767 Old Madison Pike, Suite 450, Huntsville, AL 35806 (United States); Kouveliotou, C.; Collazzi, A. [Astrophysics Office, ZP 12, NASA-Marshall Space Flight Center, Huntsville, AL 35812 (United States); Van der Horst, A. J.; Watts, A. L.; Huppenkothen, D.; Van der Klis, M.; Van Putten, T. [Astronomical Institute "Anton Pannekoek," University of Amsterdam, Postbus 94249, 1090 GE Amsterdam (Netherlands); Baring, M. G. [Department of Physics and Astronomy, Rice University, MS-108, P.O. Box 1892, Houston, TX 77251 (United States); Granot, J. [Department of Natural Sciences, The Open University of Israel, 1 University Road, P.O. Box 808, Ranana 43537 (Israel); Bhat, P. N.; Gorgone, N. [University of Alabama in Huntsville CSPAR, 320 Sparkman Drive, Huntsville, AL 35805 (United States); Gehrels, N.; Mcenery, J. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); G??, E.; Kaneko, Y.; Lin, L. [Sabanc? University, Orhanl?-Tuzla, ?stanbul 34956 (Turkey); Gruber, D.; Von Kienlin, A. [Max Planck Institute for Extraterrestrial Physics, Giessenbachstrasse, Postfach 1312, D-85748 Garching (Germany); Grunblatt, S. [University of Hawaii at Manoa, 2500 Campus Road, Honolulu, HI 96822 (United States); and others

    2014-04-10

    We report on a time-resolved spectroscopy of the 63 brightest bursts of SGR J15505418, detected with the Fermi/Gamma-ray Burst Monitor during its 2008-2009 intense bursting episode. We performed spectral analysis down to 4 ms timescales to characterize the spectral evolution of the bursts. Using a Comptonized model, we find that the peak energy, E {sub peak}, anti-correlates with flux, while the low-energy photon index remains constant at ? 0.8 up to a flux limit F ? 10{sup 5} erg s{sup 1} cm{sup 2}. Above this flux value, the E {sub peak}flux correlation changes sign, and the index positively correlates with the flux reaching ?1 at the highest fluxes. Using a two blackbody model, we find that the areas and fluxes of the two emitting regions correlate positively. Further, we study here for the first time the evolution of the temperatures and areas as a function of flux. We find that the areakT relation follows the lines of constant luminosity at the lowest fluxes, R {sup 2}?kT {sup 4}, with a break at the higher fluxes (F > 10{sup 5.5} erg s{sup 1} cm{sup 2}). The area of the high-kT component increases with the flux while its temperature decreases, which we interpret as being due to an adiabatic cooling process. The area of the low-kT component, on the other hand, appears to saturate at the highest fluxes, toward R {sub max} ? 30 km. Assuming that crust quakes are responsible for soft gamma repeater (SGR) bursts and considering R {sub max} as the maximum radius of the emitting photon-pair plasma fireball, we relate this saturation radius to a minimum excitation radius of the magnetosphere, and we put a lower limit on the internal magnetic field of SGR J15505418, B {sub int} ? 4.5 10{sup 15} G.

  17. FHR Process Instruments

    SciTech Connect (OSTI)

    Holcomb, David Eugene

    2015-01-01

    Fluoride salt-cooled High temperature Reactors (FHRs) are entering into early phase engineering development. Initial candidate technologies have been identified to measure all of the required process variables. The purpose of this paper is to describe the proposed measurement techniques in sufficient detail to enable assessment of the proposed instrumentation suite and to support development of the component technologies. This paper builds upon the instrumentation chapter of the recently published FHR technology development roadmap. Locating instruments outside of the intense core radiation and high-temperature fluoride salt environment significantly decreases their environmental tolerance requirements. Under operating conditions, FHR primary coolant salt is a transparent, low-vapor-pressure liquid. Consequently, FHRs can employ standoff optical measurements from above the salt pool to assess in-vessel conditions. For example, the core outlet temperature can be measured by observing the fuel s blackbody emission. Similarly, the intensity of the core s Cerenkov glow indicates the fission power level. Short-lived activation of the primary coolant provides another means for standoff measurements of process variables. The primary coolant flow and neutron flux can be measured using gamma spectroscopy along the primary coolant piping. FHR operation entails a number of process measurements. Reactor thermal power and core reactivity are the most significant variables for process control. Thermal power can be determined by measuring the primary coolant mass flow rate and temperature rise across the core. The leading candidate technologies for primary coolant temperature measurement are Au-Pt thermocouples and Johnson noise thermometry. Clamp-on ultrasonic flow measurement, that includes high-temperature tolerant standoffs, is a potential coolant flow measurement technique. Also, the salt redox condition will be monitored as an indicator of its corrosiveness. Both

  18. X-RAY AND OPTICAL OBSERVATIONS OF THE UNIQUE BINARY SYSTEM HD 49798/RX J0648.0-4418

    SciTech Connect (OSTI)

    Mereghetti, S.; La Palombara, N.; Tiengo, A.; Pizzolato, F.; Esposito, P.; Woudt, P. A.; Israel, G. L.; Stella, L.

    2011-08-20

    We report the results of XMM-Newton observations of HD 49798/RX J0648.0-4418, the only known X-ray binary consisting of a hot sub-dwarf and a white dwarf. The white dwarf rotates very rapidly (P = 13.2 s) and has a dynamically measured mass of 1.28 {+-} 0.05 M{sub sun}. Its X-ray emission consists of a strongly pulsed, soft component, well fit by a blackbody with kT{sub BB} {approx} 40 eV, accounting for most of the luminosity, and a fainter hard power-law component (photon index {approx}1.6). A luminosity of {approx}10{sup 32} erg s{sup -1} is produced by accretion onto the white dwarf of the helium-rich matter from the wind of the companion, which is one of the few hot sub-dwarfs showing evidence of mass loss. A search for optical pulsations at the South African Astronomical Observatory 1.9 m telescope gave negative results. X-rays were also detected during the white dwarf eclipse. This emission, with luminosity 2 x 10{sup 30} erg s{sup -1}, can be attributed to HD 49798 and represents the first detection of a hot sub-dwarf star in the X-ray band. HD 49798/RX J0648.0-4418 is a post-common-envelope binary which most likely originated from a pair of stars with masses {approx}8-10 M{sub sun}. After the current He-burning phase, HD 49798 will expand and reach the Roche lobe, causing a higher accretion rate onto the white dwarf which can reach the Chandrasekhar limit. Considering the fast spin of the white dwarf, this could lead to the formation of a millisecond pulsar. Alternatively, this system could be a Type Ia supernova progenitor with the appealing characteristic of a short time delay, being the descendent of relatively massive stars.

  19. SWIFT X-RAY AND ULTRAVIOLET MONITORING OF THE CLASSICAL NOVA V458 VUL (NOVA VUL 2007)

    SciTech Connect (OSTI)

    Ness, J.-U. [European Space Astronomy Centre, P.O. Box 78, 28691 Villanueva de la Canada, Madrid (Spain); Drake, J. J. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Beardmore, A. P.; Evans, P. A.; Osborne, J. P.; Page, K. L. [Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH (United Kingdom); Boyd, D. [BAA VSS, 5 Silver Lane, West Challow, Wantage, OX12 9TX (United Kingdom); Bode, M. F. [Astrophysics Research Institute, Liverpool John Moores University, Twelve Quays House, Egerton Wharf, Birkenhead CH41 1LD (United Kingdom); Brady, S. [AAVSO, 5 Melba Drive, Hudson, NH 03051 (United States); Gaensicke, B. T.; Steeghs, D. [Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom); Kitamoto, S.; Takei, D. [Department of Physics, Rikkyo University, 3-34-1 Nishi-Ikebukuro, Toshima, Tokyo 171-8501 (Japan); Knigge, C. [School of Physics and Astronomy, University of Southampton, Southampton SO17 1BJ (United Kingdom); Miller, I. [BAA VSS, Furzehill House, Ilston, Swansea SA2 7LE (United Kingdom); Rodriguez-Gil, P. [Isaac Newton Group, PO Ap. de Correos 321, 38700 Sta. Cruz de la Palma (Spain); Schwarz, G. [Department of Geology and Astronomy, West Chester University, West Chester, PA 19383 (United States); Staels, B. [CBA Flanders, Alan Guth Observatory, Koningshofbaan 51, Hofstade, Aalst (Belgium); Tsujimoto, M. [Department of Astronomy and Astrophysics, Pennsylvania State University, 525 Davey Laboratory, University Park, PA 16802 (United States); Wesson, R. [Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom)], E-mail: juness@sciops.esa.int (and others)

    2009-05-15

    We describe the highly variable X-ray and UV emission of V458 Vul (Nova Vul 2007), observed by Swift between 1 and 422 days after outburst. Initially bright only in the UV, V458 Vul became a variable hard X-ray source due to optically thin thermal emission at kT = 0.64 keV with an X-ray band unabsorbed luminosity of 2.3 x 10{sup 34} erg s{sup -1} during days 71-140. The X-ray spectrum at this time requires a low Fe abundance (0.2{sup +0.3} {sub -0.1} solar), consistent with a Suzaku measurement around the same time. On day 315 we find a new X-ray spectral component which can be described by a blackbody with temperature of kT = 23{sup +9} {sub -5} eV, while the previous hard X-ray component has declined by a factor of 3.8. The spectrum of this soft X-ray component resembles those typically seen in the class of supersoft sources (SSS) which suggests that the nova ejecta were starting to clear and/or that the white dwarf photosphere is shrinking to the point at which its thermal emission reaches into the X-ray band. We find a high degree of variability in the soft component with a flare rising by an order of magnitude in count rate in 0.2 days. In the following observations on days 342.4-383.6, the soft component was not seen, only to emerge again on day 397. The hard component continued to evolve, and we found an anticorrelation between the hard X-ray emission and the UV emission, yielding a Spearman rank probability of 97%. After day 397, the hard component was still present, was variable, and continued to fade at an extremely slow rate but could not be analyzed owing to pile-up contamination from the bright SSS component.

  20. LONG-TERM SPECTRAL VARIATIONS OF ULTRALUMINOUS X-RAY SOURCES IN THE INTERACTING GALAXY SYSTEMS M 51 AND NGC 4490/85

    SciTech Connect (OSTI)

    Yoshida, Tessei; Ebisawa, Ken; Tsujimoto, Masahiro [Japan Aerospace Exploration Agency, Institute of Space and Astronautical Science, 3-1-1 Yoshinodai, Chuo, Sagamihara, Kanagawa 252-5210 (Japan); Matsushita, Kyoko [Department of Physics, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku, Tokyo 162-8601 (Japan); Kawaguchi, Toshihiro, E-mail: yoshida.tessei@ac.jaxa.j [Center for Computational Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577 (Japan)

    2010-10-10

    Variable ultraluminous X-ray sources (ULXs), which are considered to be black hole binaries (BHBs), are known to show state transitions similar to Galactic BHBs. However, the relation between the ULX states and the Galactic BHB states is still unclear, primarily due to the less well-understood behaviors of ULXs in contrast to the Galactic BHBs. Here, we report a statistical X-ray spectral study of 34 energy spectra from seven bright ULXs in the interacting galaxy systems M 51 and NGC 4490/85, using archive data from multiple Chandra and XMM-Newton observations spanning a few years. In order to compare them with Galactic BHB states, we applied representative spectral models of BHBs-a power-law (PL), a multi-color disk blackbody (MCD), and a slim-disk model-to all the ULX spectra. We found a hint of a bimodal structure in the luminosity distribution of the samples, suggesting that ULXs have two states that respectively have typical luminosities of (3-6)x 10{sup 39} and (1.5-3)x 10{sup 39} ergs s{sup -1}. Most spectra in the brighter state are explained by the MCD or the slim-disk model, whereas those in the fainter state are explained by the PL model. In particular, the slim-disk model successfully explains the observed spectral variations of NGC 4490/85 ULX-6 and ULX-8 by changes of the mass accretion rate to a black hole of an estimated mass of <40 M{sub sun}. From the best-fit model parameters of each state, we speculate that the brighter state in these two ULXs corresponds to the brightest state of Galactic BHBs, which is often called the 'apparently standard state'. The fainter state of the ULXs has a PL-shaped spectrum, but the photon index range is much wider than that seen in any single state of Galactic BHBs. We thus speculate that it is a state unique to ULXs. Some sources show much fainter and steeper spectra than the faint state, which we identified as yet another state.