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1

Determining cosmic microwave background anisotropies in the presence of foregrounds  

E-Print Network (OSTI)

Separating foregrounds from the signal is one of the big challenges in cosmic microwave background (CMB) experiments. A simple way to estimate the CMB temperature in a given pixel is to fit for the amplitudes of the CMB and the various foreground components. The variance squared of this estimator is shown to be equal to $[(FDF)^2\\ \\sigzt + \\sigsh^2]$, where $\\sigz$ is the variance in the absence of foregrounds; $\\sigsh$ is the variance due to the uncertainty in the shapes of the foreground components; and FDF is the {\\it foreground degradation factor}. This one number, the FDF, gives a good indication of the ability of a given experiment to disentangle the CMB from foreground sources. A variety of applications relating to the planning and analyzing of experiments is presented.

Scott Dodelson

1995-12-05T23:59:59.000Z

2

Background foreground segmentation with RGB-D Kinect data: An efficient combination of classifiers  

Science Journals Connector (OSTI)

Low cost RGB-D cameras such as the Microsoft's Kinect or the Asus's Xtion Pro are completely changing the computer vision world, as they are being successfully used in several applications and research areas. Depth data are particularly attractive and ... Keywords: Background/foreground segmentation, Color and depth data combination, Combination of classifiers, Microsoft Kinect, Mixture of Gaussian, Object detection, RGB-D cameras, RGB-D dataset

Massimo Camplani; Luis Salgado

2014-01-01T23:59:59.000Z

3

Polarization of the Atmosphere as a Foreground for Cosmic Microwave Background Polarization Experiments  

E-Print Network (OSTI)

We quantify the level of polarization of the atmosphere due to Zeeman splitting of oxygen in the Earth's magnetic field and compare it to the level of polarization expected from the polarization of the cosmic microwave background radiation. The analysis focuses on the effect at mid-latitudes and at large angular scales. We find that from stratospheric balloon borne platforms and for observations near 100 GHz the atmospheric linear and circular polarized intensities is about 10^{-12} and 100 x 10^{-9} K, respectively, making the atmosphere a negligible source of foreground. From the ground the linear and circular polarized intensities are about 10^{-9} and 100 x 10^{-6} K, making the atmosphere a potential source of foreground for the CMB E (B) mode signal if there is even a 1% (0.01%) conversion of circular to linear polarization in the instrument.

Shaul Hanany; Philip Rosenkranz

2003-07-02T23:59:59.000Z

4

The Beaver  

NLE Websites -- All DOE Office Websites (Extended Search)

Beaver Beaver Nature Bulletin No. 246-A November 26, 1966 Forest Preserve District of Cook County Seymour Simon, President Roland F. Eisenbeis, Supt. of Conservation THE BEAVER The beaver was the first hydraulic engineer. Back in the days when our ancestors were still living in caves, the beaver had been building elaborate dams across streams, digging canals, and sleeping safely in artificial-island homes for thousands of years. This had a profound effect on streams and stream valleys in Europe, Siberia and most of North America, literally changing the face of the earth. Their dams held back flood waters in wet seasons, maintained the flow of streams in times of drought, and built up ground water supplies. The ponds above these dams, which were occasionally more than 1000 feet long, allowed sediment to settle out of the water and form broad meadows which eventually were occupied by tracts of timber and, now, some of our finest farmland. Waterfowl, fish, and a host of other living things thrived here because of the beaver.

5

beaver.html  

NLE Websites -- All DOE Office Websites (Extended Search)

Beavers - Mother Nature's Engineers Beavers - Mother Nature's Engineers Prairie Resources - Exhibit Home Do beavers live on Fermilab property? Yes. Several beavers' lodges can be spotted on Fermilab's site. Since beavers, Castor canadensis, are mostly nocturnal animals, they are rarely seen during the day. But a visitor might find evidence of the existence of about twenty resident beavers. Why are beavers called "Mother Nature's Engineers"? Beavers are born knowing how to build lodges and dams. They stand on their hind legs and cut down trees, while balancing on their tail. They cut down as many as 200 trees a year, mostly soft-wood trees such as cotton-woods or willows. This actually helps the groundcrew of Fermilab to curb the growth of unwanted trees. The beavers then start their building by holding large

6

FOREGROUND PREDICTIONS FOR THE COSMIC MICROWAVE BACKGROUND POWER SPECTRUM FROM MEASUREMENTS OF FAINT INVERTED RADIO SOURCES AT 5 GHz  

SciTech Connect

We present measurements of a population of matched radio sources at 1.4 and 5 GHz down to a flux limit of 1.5 mJy in 7 deg{sup 2} of the NOAO Deep Field South. We find a significant fraction of sources with inverted spectral indices that all have 1.4 GHz fluxes less than 10 mJy and are therefore too faint to have been detected and included in previous radio source count models that are matched at multiple frequencies. Combined with the matched source population at 1.4 and 5 GHz in 1 deg{sup -2} in the ATESP survey, we update models for the 5 GHz differential number counts and distributions of spectral indices in 5 GHz flux bins that can be used to estimate the unresolved point source contribution to the cosmic microwave background temperature anisotropies. We find a shallower logarithmic slope in the 5 GHz differential counts than in previously published models for fluxes {approx}< 100 mJy as well as larger fractions of inverted spectral indices at these fluxes. Because the Planck flux limit for resolved sources is larger than 100 mJy in all channels, our modified number counts yield at most a 10% change in the predicted Poisson contribution to the Planck temperature power spectrum. For a flux cut of 5 mJy with the South Pole Telescope and a flux cut of 20 mJy with the Atacama Cosmology Telescope, we predict a {approx}30% and {approx}10% increase, respectively, in the radio source Poisson power in the lowest frequency channels of each experiment relative to that predicted by previous models.

Schneider, Michael D. [Lawrence Livermore National Laboratory, P.O. Box 808 L-210, Livermore, CA 94551 (United States); Becker, Robert H. [Department of Physics, University of California, One Shields Avenue, Davis, CA 08991 (United States); De Vries, Willem [Lawrence Livermore National Laboratory, P.O. Box 808 L-211, Livermore, CA 94551 (United States); White, Richard L., E-mail: schneider42@llnl.gov [Space Telescope Science Institute, Baltimore, MD 21218 (United States)

2012-05-10T23:59:59.000Z

7

NSA-Beaver Pond Site  

NLE Websites -- All DOE Office Websites (Extended Search)

Beaver Pond Site (NSA-BP) Beaver Pond Site (NSA-BP) The storage tent and gas collectors NSA-BP site looking to the east. Visible is the investigator hut on drier land to the west and the boardwalk leading out to the tower site in the right portion of the image with the mounded beaver lodge visible in the middle of the image. The bridge and the 3 meter flux tower The beaver lodge The bridge from the flux tower This is the floating bridge leading from the flux tower back to the shore. The large tent for holding equipment is clearly visible on the shore. The TGB gas collectors on the beaver pond Back to the BOREAS Photo Page Index Other Sites: NSA Photos ||NSA-BP Photos | NSA-Fen Photos | NSA-OA Photos | NSA-OBS Photos | NSA-OJP Photos | NSA-UBS Photos | NSA-YJP Photos | NSA-Ops Photos

8

Building Energy Software Tools Directory: BEAVER  

NLE Websites -- All DOE Office Websites (Extended Search)

BEAVER BEAVER Logo for BEAVER WINDOWS environment for the ESPII Fortran program which estimates the energy consumption of buildings using the ASHRAE Response Factor Method. BEAVER building energy simulation provides for user friendly input of data, processing and viewing of the results. BEAVER estimates the energy consumption of a building hourly over a given period of time taking into account the site location, the building structure and the type of building services installed to maintain the desired environmental conditions. It enables a designer to investigate alternatives and make energy comparisons quickly and effectively for a very wide range of building configurations and air conditioning systems using actual measured climatic data. A comprehensive range of air handling systems, primary plant and control

9

BACKGROUND  

NLE Websites -- All DOE Office Websites (Extended Search)

BACKGROUND The safe and environmentally conscious performance of work is a fundamental core value of the Hanford Advisory Board. The Department of Energy (DOE) in seeking to move...

10

Beaver City Corporation (Utility Company) | Open Energy Information  

Open Energy Info (EERE)

Corporation (Utility Company) Corporation (Utility Company) Jump to: navigation, search Name Beaver City Corporation Place Utah Utility Id 1434 Utility Location Yes Ownership M NERC Location WECC NERC WECC Yes Operates Generating Plant Yes Activity Generation Yes Activity Retail Marketing Yes References EIA Form EIA-861 Final Data File for 2010 - File1_a[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Utility Rate Schedules Grid-background.png Demand Service- Above 7.5 kW or at City Option Commercial General Commercial Service Commercial Irrigation Service Commercial Residential Service Residential Residential Service Outside City Limits Residential Street Lighting- Customer Owner Lighting Average Rates

11

BACKGROUND  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Emergency Medical Coordination Emergency Medical Coordination Memorandum of Agreement at Brookhaven National Laboratory DOE/IG-0594 March 2003 Department of Energy Washington, DC 20585 March 3 1,2003 FROM: Inspector General SUBJECT: INFORMATION: Report on Inspection of "Emergency Medical Coordination Memorandum of Agreement at Brookhaven National Laboratory" BACKGROUND Because of possible exposure to radioactive and hazardous materials and the potential for industrial accidents at Department of Energy (DOE) sites, the Department has established formalized agreements with local emergency medical providers. These arrangements are generally documented through memoranda of agreements (MOAs). These documents detail the m u

12

Background  

Office of Legacy Management (LM)

explains the potential health hazards associated with air quality related to the removal and storage of explains the potential health hazards associated with air quality related to the removal and storage of mill tailings and other contaminated materials. Background From 1942 to 1960, uranium ore was processed at the Monticello mill in southeast Utah. When the mill was closed, approximately 2.3 million cubic yards of low-level radioactive mill tailings, contaminated soil, and other miscellaneous debris remained on the site. The U.S. Department of Energy (DOE) Grand Junction Projects Office, in conjunction with the U.S. Environmental Protection Agency (EPA) and the State of Utah, is conducting the cleanup of the millsite and more than 400 area homes and businesses contaminated with mill tailings. The purpose of the cleanup is to minimize risks to the public and the

13

Background  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Format for the one pager: Report Statement/Recommendation Format for the one pager: Report Statement/Recommendation Background Pros/Cons discussion We would like to see good drafts by noon. 3/30/01. 11 circulate them as soon as I get them in. Any questions, give me a call. 456-7874 Charlie ___ ___ _8171 DOE015-1514 Martin, Adrienne ^ From: Anderson, Margot / / Sent: Thursday, March 29, 2001 723 PM To: 'Andrew D. Lundquisltovp.eop.gov%intemet' Subject: RE: 1 spoke with Charlie and we got it fixed. Thanksl -Original Message- From: Andrew D. Lundquist@ovp.eop.gov%intemet Imailto:Andrew D. Lundquistovp.eop.gov] Sent: Thursday March 29, 2001 7:18 PM To: Anderson. Margot Cc: Kelliher, Joseph; Kolevar, Kevin; Charles M. Smthovp.egov%htemet; Juleanna FR GOovsWeovp.eop.gov%intemet 'kmurphyiosec.doc.gov%intemet 'dina.eisOdo.treas.gov%intemer;

14

Background  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Patent Rights in the New Patent Rights in the New Independent States (NIS) of the Former Soviet Union for Inventions made by NIS institutes' employeess in the course of or under agreements entered into pursuant to the Fiscal Year 1994 Foreign Operations Appropriations Act (P.L. 103- 87). W(C) 94-001 Background The dissolution of the Soviet Union and the drastic reductions in defense spending by the NIS have created an extremely difficult situation for the scientists and engineers who are responsible for the former Soviet Union's defense technology base. It is estimated that there are several tens of thousands of such scientists and engineers; they possess critical technical knowledge about weapons of mass destruction and are underemployed and undercompensated, and consequently, could contribute to

15

Foreground Removal vs. Foreground Avoidance: Contamination of the EoR Window  

E-Print Network (OSTI)

The removal of the Galactic and extragalactic foregrounds remains a major challenge for those wishing to make a detection of the Epoch of Reionization 21-cm signal. Multiple methods of modelling these foregrounds with varying levels of assumption have been trialled and shown promising recoveries on simulated data. Recently however there has been increased discussion of using the expected shape of the foregrounds in Fourier space to define an EoR window free of foreground contamination. By carrying out analysis within this window only, one can avoid the foregrounds and any statistical bias they might introduce. In this paper we discuss the advantages and disadvantages of both foreground removal and foreground avoidance. We create a series of simulations with noise levels in line with both current and future experiments and compare the recovered statistical cosmological signal from both methods. We also relax the assumption that the foregrounds are smooth by introducing a Gaussian random factor along the line-o...

Chapman, Emma; Abdalla, Filipe

2014-01-01T23:59:59.000Z

16

Foreground removal for SKA EoR with the Correlated Component Analysis  

E-Print Network (OSTI)

We apply the Correlated Component Analysis (CCA) method on simulated data of the Square Kilometre Array, with the aim of accurately cleaning the 21 cm reionization signal from diffuse foreground contamination. The CCA has been developed for the Cosmic Microwave Background, but the application of the Fourier-domain implementation of this method to the reionization signal is straightforward. The CCA is a parametric method to estimate the frequency behaviour of the foregrounds from the data by using second-order statistics. We test its performance on foreground simulations of increasing complexity, designed to challenge the parametric models adopted. We also drop the assumption of spectral smoothness that most of the methods rely upon. We are able to clean effectively the simulated data across the explored frequency range (100-200 MHz) for all the foreground simulations. This shows that the CCA method is very promising for EoR component separation.

Bonaldi, Anna

2014-01-01T23:59:59.000Z

17

Influence of beaver impoundments on vegetative composition, and modeling habitat suitability as a tool for wildlife management and conservation.  

E-Print Network (OSTI)

??Beavers (Castor canadensis) can have dramatic effects on vegetative communities through impounding streams and wetlands. These alterations may influence rare plant species where beaver create… (more)

Bonner, Jerri LeAnne.

2005-01-01T23:59:59.000Z

18

Vegetative composition and community structure associated with beaver ponds in Canaan valley, West Virginia, USA  

Science Journals Connector (OSTI)

Beavers (Castor canadensis...) can cause dramatic changes in vegetative composition and diversity. Although alterations by beaver have been studied extensively, little attention has been paid to the effects beave...

Jerri L. Bonner; James T. Anderson; James S. Rentch…

2009-10-01T23:59:59.000Z

19

An Improved Method for 21cm Foreground Removal  

E-Print Network (OSTI)

21-cm tomography is expected to be difficult in part because of serious foreground contamination. Previous studies have found that line-of-sight approaches are capable of cleaning foregrounds to an acceptable level on large ...

Liu, Adrian

20

E-Print Network 3.0 - ac backgrounder table Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

Vachon Summary: -surveillance, optical motion capture and multimedia application. The process mainly used is the background subtraction... as foreground or background. Some...

Note: This page contains sample records for the topic "foreground background beaver" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Boralex Beaver Livermore Falls Biomass Facility | Open Energy Information  

Open Energy Info (EERE)

Livermore Falls Biomass Facility Livermore Falls Biomass Facility Jump to: navigation, search Name Boralex Beaver Livermore Falls Biomass Facility Facility Boralex Beaver Livermore Falls Sector Biomass Location Androscoggin County, Maine Coordinates 44.1912416°, -70.1707037° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":44.1912416,"lon":-70.1707037,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

22

Update Foregrounding: Verum Focus, Prosody, and Negative Polar Questions Introduction. Verum focus is broadly associated with emphasis of propositional truth (Hohle,  

E-Print Network (OSTI)

, to be in the conversational background, i.e. given (Schwarzschild, 1999). The effect of verum is, thus, to foreground p bias, and the intuition that verum and NPQs have mirrored discourse function, without requiring

Pennsylvania, University of

23

Cross-species transmission of Giardia spp.: inoculation of beavers and muskrats with cysts of human, beaver, mouse, and muskrat origin.  

Science Journals Connector (OSTI)

...The ubiquitous geographic distribu- tion of beavers in North American obviously correlated with sites of waterborne giardiasis...Angelo. 1978. A water- borne outbreak of giardiasis in Camas, Wash. J. Am. Water Works Assoc. 70:35-40. 23. Kulda...

S L Erlandsen; L A Sherlock; M Januschka; D G Schupp; F W Schaefer 3rd; W Jakubowski; W J Bemrick

1988-11-01T23:59:59.000Z

24

Microsoft Word - CX_Beaver Creek.doc  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Clearance Memorandum Clearance Memorandum Jay Marcotte Project Manager - KEWU-4 Proposed Action: Bonneville Power Administration (BPA) funding to acquire the Beaver Creek property and to maintain this property for fish and wildlife habitat protection. Budget Information: Work Order # 00225478 Fish and Wildlife Project No.: 2009-003-00, 43451 Categorical Exclusion Applied (from Subpart D, 10 C.F.R. Part 1021): B1.25 Transfer, lease, disposition or acquisition of interests in uncontaminated land for habitat preservation or wildlife management, and only associated buildings that support these purposes. Uncontaminated means that there would be no potential for release of substances at a level, or in a form, that would pose a threat to public health or the environment.

25

Geology of the Middle Beaver Creek area, Mason and Gillespie Counties, Texas  

E-Print Network (OSTI)

AREA, NASGR AEG GILhNPIR COGRTIES, TEIAB ABSTRACT The Middle Beaver Creek area is situated on the soutlwsst flank of the Llano ?plift region in Mason and Gillespie Counties, Texas Hooks of Presa?brian, Psleosoie, Mesosois, and Genosois age... ' Figure 1. ? Map of' part of Mason and Gillespie Counties, Texass showing location of' the Middle Beaver Creek Area, on aoetats oosered aerial photographs. In order to aoourateIp locate and plot the oontaots asd faults, the photographs vere studies...

Peterson, Don Hamilton

2012-06-07T23:59:59.000Z

26

Beaver Monitoring Protocol for Forest Service Region 2 Revised May 2008 1 USDA FOREST SERVICE REGION 2  

E-Print Network (OSTI)

HILLS NATIONAL FORESTS (Photo from Nature of New England Website ­ http Black Hills National Forest, USDA Forest Service, Custer, SD Revised May 2008 #12;Beaver MonitoringBeaver Monitoring Protocol for Forest Service Region 2 ­ Revised May 2008 1 USDA FOREST SERVICE

Beck, Jeffrey L.

27

Selection between foreground models for global 21-cm experiments  

E-Print Network (OSTI)

The precise form of the foregrounds for sky-averaged measurements of the 21-cm line during and before the epoch of reionization is unknown. We suggest that the level of complexity in the foreground models used to fit global 21-cm data should be driven by the data, under a Bayesian model selection methodology. A first test of this approach is carried out by applying nested sampling to simplified models of global 21-cm data to compute the Bayesian evidence for the models. If the foregrounds are assumed to be polynomials of order n in log-log space, we can infer the necessity to use n=4 rather than n=3 with <2h of integration with limited frequency coverage, for reasonable values of the n=4 coefficient. Using a higher-order polynomial does not necessarily prevent a significant detection of the 21-cm signal. Even for n=8, we can obtain very strong evidence distinguishing a reasonable model for the signal from a null model with 128h of integration. More subtle features of the signal may, however, be lost if the...

Harker, Geraint

2015-01-01T23:59:59.000Z

28

Analysis of Small Scale MBR Anisotropy in the Presence of Foreground Contamination  

E-Print Network (OSTI)

Many of the current round of experiments searching for anisotropies in the MBR are confronting the problem of how to disentangle the cosmic signal from contamination due to galactic and intergalactic foreground sources. Here we show how commonly used likelihood function techniques can be generalized to account for foreground. Specifically we set some restrictions on the spectrum of foreground contamination but allow the amplitude to vary arbitrarily. The likelihood function thus generalized gives reasonable limits on the MBR anisotropy which, in some cases, are not much less restrictive than what one would get from more detailed modeling of the foreground. Furthermore, the likelihood function is exactly the same as one would obtain by simply projecting out foreground contamination and just looking at the reduced data set. We apply this generalized analysis to the recent medium angle data sets of ACME-HEMT and MAX. The resulting analysis constrains the one free parameter in the standard cold dark matter theory to be Q=18_-5^+8 microK. This best fit value, although in striking agreement with the normalization from COBE, is not a very good fit, with an overall chi^2/ degree of freedom =208/168. We also argue against three commonly used methods of dealing with foreground: (i) ignoring it completely; (ii) subtracting off a best fit foreground and treating the residuals as if uncontaminated; and (iii) culling data which appears to be contaminated by foreground.

Scott Dodelson; Albert Stebbins

1993-10-28T23:59:59.000Z

29

Intra-amygdala infusion of the protein kinase Mzeta inhibitor ZIP disrupts foreground context fear memory  

E-Print Network (OSTI)

Intra-amygdala infusion of the protein kinase Mzeta inhibitor ZIP disrupts foreground context fear-pseudosubstrate inhibitory peptide (ZIP) remains in the brain after infusion. Here, we demon- strate that foreground context the brain by 24 h after infusion. These data contribute to a growing body of lit- erature that demonstrates

Helmstetter, Fred J.

30

Habitat Evaluation Procedures (HEP) Report; West Beaver Lake Project, Technical Report 2005  

SciTech Connect

On September 7, 2004, the Habitat Evaluation Procedure (HEP) was used to determine baseline habitat suitability on the West Beaver Lake property, an acquisition completed by the Kalispel Tribe of Indians in September 2004. Evaluation species and appropriate models include bald eagle, black-capped chickadee, mallard, muskrat, and white-tailed deer. Habitat Suitability Index (HSI) values were visually estimated and agreed upon by all HEP team members. The West Beaver Lake Project provides a total of 82.69 Habitat Units (HUs) for the species evaluated. Emergent wetland habitat provides 8.80 HUs for mallard, muskrat, and Canada goose. Conifer forest habitat provides 70.33 HUs for bald eagle, black-capped chickadee, mallard, and white-tailed deer. Open water provides 3.30 HUs for mallard, muskrat, and Canada goose. The objective of using HEP at the West Beaver Lake Project and other protected properties is to document the quality and quantity of available habitat for selected wildlife species. In this way, HEP provides information on the relative value of the same area at future points in time so that the effect of management activities on wildlife habitat can be quantified. When combined with other tools, the baseline HEP will be used to determine the most effective on-site management, restoration, and enhancement actions to increase habitat suitability for targeted species. The same process will be replicated every five years to quantitatively evaluate the effectiveness of management strategies in improving and maintaining habitat conditions while providing additional crediting to BPA for enhanced habitat values.

Entz, Ray

2005-05-01T23:59:59.000Z

31

A Strategy to Minimize Dust Foregrounds in B-mode Searches  

E-Print Network (OSTI)

The Planck satellite has identified several patches of sky with low polarized dust emission, obvious targets for searches for the cosmic-microwave-background (CMB) B-mode signal from inflationary gravitational waves. Still, given the Planck measurement uncertainties, the polarized dust foregrounds in these different candidate patches may differ by an order of magnitude or more. Here we show that a brief initial experiment to map these candidate patches more deeply at a single high frequency can efficiently zero in on the cleanest patch(es) and thus improve significantly the sensitivity of subsequent B-mode searches. A ground-based experiment with current detector technology operating at >~220 GHz for 3 months can efficiently identify a low-dust-amplitude patch and thus improve by up to 20%-60% on the sensitivity to cosmic B modes of the subsequent lower-frequency deep integration. A balloon experiment with current detector sensitivities covering the set of patches and operating at ~350 GHz can reach a similar...

Kovetz, Ely D

2015-01-01T23:59:59.000Z

32

Cosmic Dawn and Epoch of Reionization Foreground Removal with the SKA  

E-Print Network (OSTI)

The exceptional sensitivity of the SKA will allow observations of the Cosmic Dawn and Epoch of Reionization (CD/EoR) in unprecedented detail, both spectrally and spatially. This wealth of information is buried under Galactic and extragalactic foregrounds, which must be removed accurately and precisely in order to reveal the cosmological signal. This problem has been addressed already for the previous generation of radio telescopes, but the application to SKA is different in many aspects. In this chapter we summarise the contributions to the field of foreground removal in the context of high redshift and high sensitivity 21-cm measurements. We use a state-of-the-art simulation of the SKA Phase 1 observations complete with cosmological signal, foregrounds and frequency-dependent instrumental effects to test both parametric and non-parametric foreground removal methods. We compare the recovered cosmological signal using several different statistics and explore one of the most exciting possibilities with the SKA ...

Chapman, Emma; Harker, Geraint; Jeli?, Vibor; Abdalla, Filipe B; Bernardi, Gianni; Bobin, Jérôme; Dulwich, Fred; Mort, Benjamin; Santos, Mario; Starck, Jean-Luc

2015-01-01T23:59:59.000Z

33

Foreground Removal using FastICA: A Showcase of LOFAR-EoR  

E-Print Network (OSTI)

We introduce a new implementation of the FastICA algorithm on simulated LOFAR EoR data with the aim of accurately removing the foregrounds and extracting the 21-cm reionization signal. We find that the method successfully removes the foregrounds with an average fitting error of 0.5 per cent and that the 2D and 3D power spectra are recovered across the frequency range. We find that for scales above several PSF scales the 21-cm variance is successfully recovered though there is evidence of noise leakage into the reconstructed foreground components. We find that this blind independent component analysis technique provides encouraging results without the danger of prior foreground assumptions.

Chapman, Emma; Harker, Geraint; Jeli?, Vibor; Labropoulos, Panagiotis; Zaroubi, Saleem; Brentjens, Michiel A; de Bruyn, A G; Koopmans, L V E

2012-01-01T23:59:59.000Z

34

The Cosmic Background Imager  

E-Print Network (OSTI)

The Cosmic Background Imager (CBI) is an instrument designed to make images of the cosmic microwave background radiation and to measure its statistical properties on angular scales from about 3 arc minutes to one degree (spherical harmonic scales from l ~ 4250 down to l ~ 400). The CBI is a 13-element interferometer mounted on a 6 meter platform operating in ten 1-GHz frequency bands from 26 GHz to 36 GHz. The instantaneous field of view of the instrument is 45 arcmin (FWHM) and its resolution ranges from 3 to 10 arcmin; larger fields can be imaged by mosaicing. At this frequency and resolution, the primary foreground is due to discrete extragalactic sources, which are monitored at the Owens Valley Radio Observatory and subtracted from the CBI visibility measurements. The instrument has been making observations since late 1999 of both primordial CMB fluctuations and the Sunyaev-Zeldovich effect in clusters of galaxies from its site at an altitude of 5080 meters near San Pedro de Atacama, in northern Chile. Observations will continue until August 2001 or later. We present preliminary results from the first few months of observations.

T. J. Pearson; B. S. Mason; S. Padin; A. C. S. Readhead; M. C. Shepherd; J. Sievers; P. S. Udomprasert; J. K. Cartwright

2000-12-11T23:59:59.000Z

35

The Cosmic Background Imager  

E-Print Network (OSTI)

Design and performance details are given for the Cosmic Background Imager (CBI), an interferometer array that is measuring the power spectrum of fluctuations in the cosmic microwave background radiation (CMBR) for multipoles in the range 400 < l < 3500. The CBI is located at an altitude of 5000 m in the Atacama Desert in northern Chile. It is a planar synthesis array with 13 0.9-m diameter antennas on a 6-m diameter tracking platform. Each antenna has a cooled, low-noise receiver operating in the 26-36 GHz band. Signals are cross-correlated in an analog filterbank correlator with ten 1 GHz bands. This allows spectral index measurements which can be used to distinguish CMBR signals from diffuse galactic foregrounds. A 1.2 kHz 180-deg phase switching scheme is used to reject cross-talk and low-frequency pick-up in the signal processing system. The CBI has a 3-axis mount which allows the tracking platform to be rotated about the optical axis, providing improved (u,v) coverage and a powerful discriminant against false signals generated in the receiving electronics. Rotating the tracking platform also permits polarization measurements when some of the antennas are configured for the orthogonal polarization.

S. Padin; M. C. Shepherd; J. K. Cartwright; R. G. Keeney; B. S. Mason; T. J. Pearson; A. C. S. Readhead; W. L. Schaal; J. Sievers; P. S. Udomprasert; J. K. Yamasaki; W. L. Holzapfel; J. E. Carlstrom; M. Joy; S. T. Myers; A. Otarola

2001-10-05T23:59:59.000Z

36

OPENING THE 21 cm EPOCH OF REIONIZATION WINDOW: MEASUREMENTS OF FOREGROUND ISOLATION WITH PAPER  

SciTech Connect

We present new observations with the Precision Array for Probing the Epoch of Reionization with the aim of measuring the properties of foreground emission for 21 cm epoch of reionization (EoR) experiments at 150 MHz. We focus on the footprint of the foregrounds in cosmological Fourier space to understand which modes of the 21 cm power spectrum will most likely be compromised by foreground emission. These observations confirm predictions that foregrounds can be isolated to a {sup w}edge{sup -}like region of two-dimensional (k , k{sub Parallel-To })-space, creating a window for cosmological studies at higher k{sub Parallel-To} values. We also find that the emission extends past the nominal edge of this wedge due to spectral structure in the foregrounds, with this feature most prominent on the shortest baselines. Finally, we filter the data to retain only this ''unsmooth'' emission and image its specific k{sub Parallel-To} modes. The resultant images show an excess of power at the lowest modes, but no emission can be clearly localized to any one region of the sky. This image is highly suggestive that the most problematic foregrounds for 21 cm EoR studies will not be easily identifiable bright sources, but rather an aggregate of fainter emission.

Pober, Jonathan C.; Parsons, Aaron R.; Ali, Zaki [Astronomy Department, U. California, Berkeley, CA (United States); Aguirre, James E.; Moore, David F. [Department of Physics and Astronomy, U. Pennsylvania, Philadelphia, PA (United States); Bradley, Richard F. [Department of Electrical and Computer Engineering, U. Virginia, Charlottesville, VA (United States); Carilli, Chris L. [National Radio Astronomy Observatory, Socorro, NM (United States); DeBoer, Dave; Dexter, Matthew; MacMahon, Dave [Radio Astronomy Laboratory, U. California, Berkeley, CA (United States); Gugliucci, Nicole E. [Department of Astronomy, U. Virginia, Charlottesville, VA (United States); Jacobs, Daniel C. [School of Earth and Space Exploration, Arizona State U., Tempe, AZ (United States); Klima, Patricia J. [National Radio Astronomy Observatory, Charlottesville, VA (United States); Manley, Jason; Walbrugh, William P. [Square Kilometer Array, South Africa Project, Cape Town (South Africa); Stefan, Irina I. [Cavendish Laboratory, Cambridge (United Kingdom)

2013-05-10T23:59:59.000Z

37

Opening the 21cm EoR Window: Measurements of Foreground Isolation with PAPER  

E-Print Network (OSTI)

We present new observations with the Precision Array for Probing the Epoch of Reionization (PAPER) with the aim of measuring the properties of foreground emission for 21cm Epoch of Reionization experiments at 150 MHz. We focus on the footprint of the foregrounds in cosmological Fourier space to understand which modes of the 21cm power spectrum will most likely be compromised by foreground emission. These observations confirm predictions that foregrounds can be isolated to a "wedge"-like region of 2D (k-perendicular, k-parallel)-space, creating a window for cosmological studies at higher k-parallel values. We also find that the emission extends past the nominal edge of this wedge due to inherent spectral structure in the foregrounds themselves, with this feature most prominent on the shortest baselines. Finally, we filter the data to retain only this "unsmooth" emission and image it. The resultant image shows an excess of power on large angular scales, but no emission can be clearly localized to any one region...

Pober, Jonathan C; Aguirre, James E; Ali, Zaki; Bradley, Richard F; Carilli, Chris L; DeBoer, Dave; Dexter, Matthew; Gugliucci, Nicole E; Jacobs, Daniel C; MacMahon, Dave; Manley, Jason; Moore, David F; Stefan, Irina I; Walbrugh, William P

2013-01-01T23:59:59.000Z

38

Foreground removal requirements for measuring large-scale CMB B modes in light of BICEP2  

Science Journals Connector (OSTI)

......experiments, we adopted the WMAP P06 mask (Page et-al. 2007), covering roughly 70cent of the sky. The LSPE is a stratospheric balloon experiment and its coverage is limited. In this case, we apply a smaller foreground mask to restrain cosmic......

A. Bonaldi; S. Ricciardi; M. L. Brown

2014-01-01T23:59:59.000Z

39

Background, But Not Foreground, Spatial Cues Are Taken as References for Head Direction Responses by Rat Anterodorsal  

E-Print Network (OSTI)

. In recordings in which rats forage for food in cylindrical enclosures, rotation of a contrasted card along by Rat Anterodorsal Thalamus Neurons Michae¨ l B. Zugaro, Alain Berthoz, and Sidney I. Wiener Centre before and after the group of objects was rotated. (The rat was disoriented in total darkness between

Sereno, Martin

40

Legal Background  

Office of Legacy Management (LM)

Legal Background Legal Background Book 1 . . Project Rulison :.Contract: . . AEC, Austral Oil Company, and CER Geonuclear Corporation, . . . . , . . . . , . . February 1969 DISCLAIMER Portions of this document may be illegible in electronic image products. Images are produced from the best available original document. PROJECT RULISON CONTRACT NO. UNITED STATES OF AMERICA REPRESENTED BY THE ATOMIC ENERGY COMMISSION and THE DEPARTMENT. OF THE INTERIOR and AUSTRAL OIL COMPANY INCORPORATED and CER GEONUCLEAR CORPORATION Prepared by OFFICE OF THE CHIEF COUNSEL NEVADA OPERATIONS OFFICE FEBRUARY 1969 This page intentionally left blank UNITED STATES ATOMIC ENERGY COMMISSION . NEVADA OPERATIONS OFFICE TABLE OF CONTENTS VII VIII XV XVI XVII SUBJECT - PAGE Definitions 2 Description of Project ~ulisdn 3

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to obtain the most current and comprehensive results.


41

The Fundamental Multi-Baseline Mode-Mixing Foreground in 21 cm EoR Observations  

E-Print Network (OSTI)

The primary challenge for experiments measuring the neutral hydrogen power spectrum from the Epoch of Reionization (EoR) are mode-mixing effects where foregrounds from very bright astrophysical sources interact with the instrument to contaminate the EoR signal. In this paper we identify a new type of mode-mixing that occurs when measurements from non-identical baselines are combined for increased power spectrum sensitivity. This multi-baseline effect dominates the mode-mixing power and can contaminate the EoR window, an area in Fourier space previously identified to be relatively free of foreground power. Multi-baseline mode-mixing introduces characteristic shapes into the three dimensional Fourier space that are determined by the instrumental configuration and we develop an iterative approach to identifying and removing mode-mixed power based on these instrumental shapes.

Hazelton, Bryna J; Sullivan, Ian S

2013-01-01T23:59:59.000Z

42

Planck CMB Anomalies: Astrophysical and Cosmological Foregrounds and the Curse of Masking  

E-Print Network (OSTI)

Understanding the origin of reported anomalies in the CMB is fundamental to either validate the standard model of cosmology or to explore new physics. Their confirmation with Planck data suggests they are not due to a problem in WMAP or Planck data. We investigate three other possible issues: 1) the trade-off between minimising systematics due to foreground contamination (with a conservative mask) and minimising systematics due to masking, 2) astrophysical foregrounds (the kinetic Doppler quadrupole and kinetic Sunyaev-Zel'dovich effect), and 3) secondary cosmological signals (the integrated Sachs-Wolfe effect). We address the masking issue by considering new procedures that use both WMAP and Planck to produce higher quality full-sky maps using the sparsity methodology (LGMCA maps). We show the impact of masking is dominant over that of residual foregrounds, and the LGMCA full-sky maps can be used without further processing to study anomalies. We consider four official Planck PR1 and two LGMCA CMB maps. Analy...

Rassat, A; Paykari, P; Sureau, F; Bobin, J

2014-01-01T23:59:59.000Z

43

CMVRTC: Background  

NLE Websites -- All DOE Office Websites (Extended Search)

newsletters newsletters contacts tools latest news 12.05.2013 Next Quarterly meeting scheduled for February 19, 2014 (10 a.m. - 12 p.m. ET). read more ... More information CMVRTC Showcase Events CMVRTC Poster Sessions Related Projects Heavy Truck Duty Cycle Medium Truck Duty Cycle Fuel Tax Evasion Other technical director For more information, please contact Gary Capps, Technical Director, at cappsgj@ornl.gov or (865) 946-1285. Background Introduction Vision cmvrtc poster Benefits Technology Transfer Introduction The Federal Motor Carrier Safety Administration (FMCSA) launched the Commercial Motor Vehicle Roadside Technology Corridor (CMVRTC) on August 7, 2007, in partnership with the Tennessee Departments of Safety and Transportation, the Oak Ridge National Laboratory (ORNL), and the

44

Algal growth potentials and heavy-metal concentrations of the primary streams to upper Beaver Lake. Technical completion report  

SciTech Connect

Algal-growth potential was inhibited by heavy metals in upper Beaver Lake, Arkansas. Upper Beaver Lake receives water from three tributaries. One contains a small reservoir and the combined streams receive sewage input. Collections were made approximately monthly at eight sites for the Algal Assay Bottle Test (AABT) and heavy-metal analysis. In general, AABT results indicated that the collections above the sewage input were phosphorus-limited while those below were nitrogen- or combined nitrogen- and phosphorus-limited. Growth inhibition occurred during summer and early fall at various sites with greater inhibition at the confluence of the streams. No inhibitions occurred at the site below the sewage input. Heavy-metal concentrations had an overall tendency to increase downstream. Values within the small reservoir were 50-100% higher than in the feeder stream. Highest values of Pb were observed below the reservoir. SO/sub 4/, Cl, Mg, Ca, Na and K had high values during low flow in August-October. Mn, Pb, and Fe exceeded EPA-recommended standards for drinking water.

Meyer, R.L.; Green, W.R.; Steele, K.F.; Wickliff, D.

1986-06-01T23:59:59.000Z

45

DOE/EA-1508: Environmental Assessment for the Beaver Creek-Hoyt-Erie Transmission Line Rebuild Project  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

BC-HT-EE Mitigation Action Plan Nov. 2005 1 BC-HT-EE Mitigation Action Plan Nov. 2005 1 Mitigation Action Plan To Implement Mitigation Requirements for Beaver Creek-Hoyt-Erie Transmission Line Upgrade Project Morgan and Weld Counties, Colorado November 2005 BC-HT-EE Mitigation Action Plan Nov. 2005 2 Action Plan for Standard Project Practices and Mitigation Mitigation Action Identifier Responsible Party for Implementing Mitigation Action Party Responsible for Monitoring and Ensuring Compliance Construction Contractor Western Maintenance The contractor shall limit the movement of crews and equipment to the ROW, including access routes. The contractor shall limit movement on the ROW to minimize damage to residential yards, grazing land, crops, orchards, and property, and shall avoid marring the lands.

46

ARM - Campaign Backgrounders  

NLE Websites -- All DOE Office Websites (Extended Search)

Annual Reports Program Fact Sheets Campaign Backgrounders Education and Outreach Posters Brochures Research Highlights Summaries Campaign Backgrounders Please contact...

47

COSMIC MICROWAVE BACKGROUND POLARIZATION AND TEMPERATURE POWER SPECTRA ESTIMATION USING LINEAR COMBINATION OF WMAP 5 YEAR MAPS  

SciTech Connect

We estimate cosmic microwave background (CMB) polarization and temperature power spectra using Wilkinson Microwave Anisotropy Probe (WMAP) 5 year foreground contaminated maps. The power spectrum is estimated by using a model-independent method, which does not utilize directly the diffuse foreground templates nor the detector noise model. The method essentially consists of two steps: (1) removal of diffuse foregrounds contamination by making linear combination of individual maps in harmonic space and (2) cross-correlation of foreground cleaned maps to minimize detector noise bias. For the temperature power spectrum we also estimate and subtract residual unresolved point source contamination in the cross-power spectrum using the point source model provided by the WMAP science team. Our TT, TE, and EE power spectra are in good agreement with the published results of the WMAP science team. We perform detailed numerical simulations to test for bias in our procedure. We find that the bias is small in almost all cases. A negative bias at low l in TT power spectrum has been pointed out in an earlier publication. We find that the bias-corrected quadrupole power (l(l + 1)C{sub l} /2{pi}) is 532 {mu}K{sup 2}, approximately 2.5 times the estimate (213.4 {mu}K{sup 2}) made by the WMAP team.

Samal, Pramoda Kumar; Jain, Pankaj [Department of Physics, Indian Institute of Technology, Kanpur (India); Saha, Rajib [Jet Propulsion Laboratory, M/S 169-327, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Delabrouille, Jacques [CNRS, Laboratoire APC, 10, rue Alice Domon et Leonie Duquet, 75205 Paris (France); Prunet, Simon [Institut d'Astrophysique de Paris, 98 bis Boulevard Arago, F-75014 Paris (France); Souradeep, Tarun [Inter-University Centre for Astronomy and Astrophysics, Post Bag 4, Ganeshkhind, Pune 411007 (India)

2010-05-01T23:59:59.000Z

48

Development of Generic Background  

NLE Websites -- All DOE Office Websites (Extended Search)

Kentucky Guidance for Ambient Background Assessment Kentucky Guidance for Ambient Background Assessment January 8, 2004 Natural Resources and Environmental Protection Cabinet Introduction This guidance document is intended to assist in comparing site data and background data for sites undergoing environmental assessment. These procedures provide a simplified statistical procedure for determining if the site data is part of the background population. It also provides generic statewide background values for inorganic chemicals that may be used in lieu of collecting site-specific background samples. The statistical procedures may be used for site- specific data or the generic statewide values in Tables 1 and 2. This guidance does not preclude other appropriate statistical comparisons from being made, but rather a simplified screening

49

The nature of the Diffuse Gamma-Ray Background  

E-Print Network (OSTI)

We review the current understanding of the diffuse gamma-ray background (DGRB). The DGRB is what remains of the total measured gamma-ray emission after the subtraction of the resolved sources and of the diffuse Galactic foregrounds. It is interpreted as the cumulative emission of sources that are not bright enough to be detected individually. Yet, its exact composition remains unveiled. Well-established astrophysical source populations (e.g. blazars, misaligned AGNs, star-forming galaxies and millisecond pulsars) all represent guaranteed contributors to the DGRB. More exotic scenarios, such as dark matter annihilation or decay, may contribute as well. In this review, we describe how these components have been modeled in the literature and how the DGRB can be used to provide valuable information on each of them. We summarize the observational information currently available on the DGRB, paying particular attention to the most recent measurement of its intensity energy spectrum by the Fermi LAT Collaboration. W...

Fornasa, Mattia

2015-01-01T23:59:59.000Z

50

ARM - Radar Backgrounder  

NLE Websites -- All DOE Office Websites (Extended Search)

News Field Notes Blog feed Events feed Employment Research Highlights Data Announcements Education News Archive What's this? Social Media Guidance Radar Backgrounder ARM Scanning...

51

Controlling Beaver Damage  

E-Print Network (OSTI)

and Reproduction Adult weight: Average 40 to 45 pounds. Total length: Approximately 3 1 ?2feet. Color: Uniform dark brown with lighter underparts. Body: Stocky. Tail: Large, flat and furred at the base. Feet: Webbed hind feet. Gestation period: About 128 days...-6 inches (76-152 mm) Marks of webs not always distinct Front foot Hind foot 6 inches (152 mm) Leghold Traps Double long spring or coil spring traps should be at least number three size in jaw spread and strength. All leghold traps should be placed in a...

Texas Wildlife Services

2007-03-13T23:59:59.000Z

52

Swift detection of all previously undetected blazars in a micro-wave flux-limited sample of WMAP foreground sources  

E-Print Network (OSTI)

Almost the totality of the bright foreground sources in the WMAP CMB maps are blazars, a class of sources that show usually also X-ray emission. However, 23 objects in a flux-limited sample of 140 blazars of the WMAP catalog (first year) were never reported before as X-ray sources. We present here the results of 41 Swift observations which led to the detection of all these 23 blazars in the 0.3-10 keV band. We conclude that all micro-wave selected blazars are X-ray emitters and that the distribution of the micro-wave to X-ray spectral slope $\\alpha_{mu x}$ of LBL blazars is very narrow, confirming that the X-ray flux of most blazars is a very good estimator of their micro-wave emission. The X-ray spectral shape of all the objects that were observed long enough to allow spectral analysis is flat and consistent with inverse Compton emission within the commonly accepted view where the radiation from blazars is emitted in a Sychrotron-Inverse-Compton scenario. We predict that all blazars and most radio galaxies above the sensitivity limit of the WMAP and of the Planck CMB missions are X-ray sources detectable by the present generation of X-ray satellites. An hypothetical all-sky soft X-ray survey with sensitivity of approximately $10^{-15}$ erg/s would be crucial to locate and remove over 100,000 blazars from CMB temperature and polarization maps and therefore accurately clean the primordial CMB signal from the largest population of extragalactic foreground contaminants.

P. Giommi; M. Capalbi; E. Cavazzuti; S. Colafrancesco; A. Cucchiara; A. Falcone; J. Kennea; R. Nesci; M. Perri; G. Tagliaferri; A. Tramacere; G. Tosti; A. J. Blustin; G. Branduardi-Raymont; D. N. Burrows; G. Chincarini; A. J. Dean; N. Gehrels; H. Krimm; F. Marshall; A. M. Parsons; B. Zhang

2007-03-07T23:59:59.000Z

53

Carbon monoxide line emission as a CMB foreground: tomography of the star-forming universe with different spectral resolutions  

E-Print Network (OSTI)

The rotational lines of carbon monoxide and the fine structure lines of CII and of the most abundant metals, emitted during the epoch of enhanced star formation in the universe, are redshifted in the frequency channels where the present-day and future CMB experiments are sensitive. We estimate the contribution to the CMB angular power spectrum by the emission in such lines in merging star-forming galaxies. We used the Lacey-Cole approach to characterize the distribution of the merging halos, together with a parametrization for the star formation rate in each of them. Using observational data from a sample of local, low-redshift, and high-redshift objects, we calibrated the luminosity in each line as a function of the star formation rate. We show that the correlation term arising from CO line emission is a significant source of foreground for CMB in a broad range of frequencies (in particular in the 20-60 GHz band) and for 1000foreground sources and from the primary fluctuations themselves, since these show no significant dependence on the spectral resolution. We propose to perform observations with varying spectral bandwidths as a new tool to construct a tomography of the universe, by probing different redshift slices with varying thickness. (abridged)

Mattia Righi; Carlos Hernandez-Monteagudo; Rashid Sunyaev

2008-07-24T23:59:59.000Z

54

THE COSMIC INFRARED BACKGROUND EXPERIMENT (CIBER): A SOUNDING ROCKET PAYLOAD TO STUDY THE NEAR INFRARED EXTRAGALACTIC BACKGROUND LIGHT  

SciTech Connect

The Cosmic Infrared Background Experiment (CIBER) is a suite of four instruments designed to study the near infrared (IR) background light from above the Earth's atmosphere. The instrument package comprises two imaging telescopes designed to characterize spatial anisotropy in the extragalactic IR background caused by cosmological structure during the epoch of reionization, a low resolution spectrometer to measure the absolute spectrum of the extragalactic IR background, and a narrow band spectrometer optimized to measure the absolute brightness of the zodiacal light foreground. In this paper we describe the design and characterization of the CIBER payload. The detailed mechanical, cryogenic, and electrical design of the system are presented, including all system components common to the four instruments. We present the methods and equipment used to characterize the instruments before and after flight, and give a detailed description of CIBER's flight profile and configurations. CIBER is designed to be recoverable and has flown four times, with modifications to the payload having been informed by analysis of the first flight data. All four instruments performed to specifications during the subsequent flights, and the scientific data from these flights are currently being analyzed.

Zemcov, M.; Bock, J.; Hristov, V.; Levenson, L. R.; Mason, P. [Department of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States); Arai, T.; Matsumoto, T.; Matsuura, S.; Tsumura, K.; Wada, T. [Department of Space Astronomy and Astrophysics, Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency (JAXA), Sagamihara, Kanagawa 252-5210 (Japan); Battle, J. [Jet Propulsion Laboratory (JPL), National Aeronautics and Space Administration (NASA), Pasadena, CA 91109 (United States); Cooray, A. [Center for Cosmology, University of California, Irvine, Irvine, CA 92697 (United States); Keating, B.; Renbarger, T. [Department of Physics, University of California, San Diego, San Diego, CA 92093 (United States); Kim, M. G. [Department of Physics and Astronomy, Seoul National University, Seoul 151-742 (Korea, Republic of); Lee, D. H.; Nam, U. W. [Korea Astronomy and Space Science Institute (KASI), Daejeon 305-348 (Korea, Republic of); Sullivan, I. [Department of Physics, The University of Washington, Seattle, WA 98195 (United States); Suzuki, K., E-mail: zemcov@caltech.edu [Instrument Development Group of Technical Center, Nagoya University, Nagoya, Aichi 464-8602 (Japan)

2013-08-15T23:59:59.000Z

55

EBSD Images Theoretical Background  

E-Print Network (OSTI)

Motivation EBSD Images Theoretical Background Defects in the Weld Grain Growth Low Speed Welding High Speed Welding Conclusion Heat-Affected Zone Observations Welding Experiments The low density in the transportation industries. Reproducibility and the low cost make welding a major large scale assembly process

Candea, George

56

Local microwave background radiation  

E-Print Network (OSTI)

An inquiry on a possible local origin for the Microwave Background Radiation is made. Thermal MBR photons are contained in a system called {\\it magnetic bottle} which is due to Earth magnetic field and solar wind particles, mostly electrons. Observational tests are anticipated.

Domingos Soares

2014-11-13T23:59:59.000Z

57

David Smith Academic background  

E-Print Network (OSTI)

David Smith Academic background Ph.D. in Mathematics (Algebra), Université de Sherbrooke, Canada project program (I. Assem, F. Bergeron, C. Reutenauer, D. Smith) $132,000 ($44,000 per year for 3 years. Schiffler and D. Smith, Friezes, strings and cluster variables, to appear in Glasgow Mathematcal Journal. 2

58

Swift detection of all previously undetected blazars in a micro-wave flux-limited sample of WMAP foreground sources  

E-Print Network (OSTI)

Almost the totality of the bright foreground sources in the WMAP CMB maps are blazars, a class of sources that show usually also X-ray emission. However, 23 objects in a flux-limited sample of 140 blazars of the WMAP catalog (first year) were never reported before as X-ray sources. We present here the results of 41 Swift observations which led to the detection of all these 23 blazars in the 0.3-10 keV band. We conclude that all micro-wave selected blazars are X-ray emitters and that the distribution of the micro-wave to X-ray spectral slope $\\alpha_{mu x}$ of LBL blazars is very narrow, confirming that the X-ray flux of most blazars is a very good estimator of their micro-wave emission. The X-ray spectral shape of all the objects that were observed long enough to allow spectral analysis is flat and consistent with inverse Compton emission within the commonly accepted view where the radiation from blazars is emitted in a Sychrotron-Inverse-Compton scenario. We predict that all blazars and most radio galaxies a...

Giommi, P; Cavazzuti, E; Colafrancesco, S; Cucchiara, A; Falcone, A; Kennea, J; Nesci, R; Perri, M; Tagliaferri, G; Tramacere, A; Tosti, G; Blustin, A J; Branduardi-Raymont, G; Burrows, D N; Chincarini, G; Dean, A J; Gehrels, N; Krimm, H; Marshall, F; Parsons, A M; Zhang, B

2007-01-01T23:59:59.000Z

59

Non-thermal Cosmic Backgrounds from Blazars: the contribution to the CMB, X-ray and gamma-ray Backgrounds  

E-Print Network (OSTI)

We present a new assessment of the contribution of Blazars to the extragalactic background radiation across the e.m. spectrum. Our calculations rely on deep Blazar radio counts that we derived combining several multifrequency surveys. The integrated Blazar emission yields a broad-band non-thermal background that in some parts of the e.m. spectrum dominates the extragalactic brightness. Blazars are the main point-like contributors to the CMB. Their integrated emission causes an apparent T increase of 5-50 muK in the 50-250 GHz range. The CMB fluctuation spectrum is sensibly contaminated at l>300, for a Poissonian source distribution, or at lower l values if spatial clustering is present. We estimate that well over 100,000 Blazars will produce a significant signal in the PLANCK CMB anisotropy maps. Because of the microwave-Xray flux correlation, these sources are expected to have flux > a few 10^{-15} erg/s in the soft X-ray band. Thus, a large fraction of the foreground sources in CMB anisotropy maps could be ...

Giommi, P; Cavazzuti, E; Perri, M; Pittori, C

2006-01-01T23:59:59.000Z

60

Paducah Background Factsheet | Department of Energy  

Office of Environmental Management (EM)

Background Factsheet Paducah Background Factsheet Background Fact Sheet Transfer of Depleted Uranium and Subsequent Transactions, May 15, 2012 Paducah Background...

Note: This page contains sample records for the topic "foreground background beaver" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Probing non-Gaussianities in the cosmic microwave background on an incomplete sky using surrogates  

Science Journals Connector (OSTI)

We demonstrate the feasibility to generate surrogates by Fourier-based methods for an incomplete data set. This is performed for the case of a cosmic microwave background analysis, where astrophysical foreground emission, mainly present in the Galactic plane, is a major challenge. The shuffling of the Fourier phases for generating surrogates is now enabled by transforming the spherical harmonics into a new set of basis functions that are orthonormal on the cut sky. The results show that non-Gaussianities and hemispherical asymmetries in the cosmic microwave background as identified in several former investigations, can still be detected even when the complete Galactic plane (|b|<30°) is removed. We conclude that the Galactic plane cannot be the dominant source for these anomalies. The results point towards a violation of statistical isotropy.

G. Rossmanith, H. Modest, C. Räth, A. J. Banday, K. M. Górski, and G. Morfill

2012-10-15T23:59:59.000Z

62

Non-thermal Cosmic Backgrounds from Blazars: the contribution to the CMB, X-ray and gamma-ray Backgrounds  

E-Print Network (OSTI)

We present a new assessment of the contribution of Blazars to the extragalactic background radiation across the e.m. spectrum. Our calculations rely on deep Blazar radio counts that we derived combining several multifrequency surveys. The integrated Blazar emission yields a broad-band non-thermal background that in some parts of the e.m. spectrum dominates the extragalactic brightness. Blazars are the main point-like contributors to the CMB. Their integrated emission causes an apparent T increase of 5-50 muK in the 50-250 GHz range. The CMB fluctuation spectrum is sensibly contaminated at l>300, for a Poissonian source distribution, or at lower l values if spatial clustering is present. We estimate that well over 100,000 Blazars will produce a significant signal in the PLANCK CMB anisotropy maps. Because of the microwave-Xray flux correlation, these sources are expected to have flux > a few 10^{-15} erg/s in the soft X-ray band. Thus, a large fraction of the foreground sources in CMB anisotropy maps could be identified and removed using a multi frequency approach, provided that a sufficiently deep all sky X-ray survey will be available. We further show that Blazars are a major constituent of all high-E extragalactic backgrounds. Their contribution is 11-12% at X-ray frequencies and possibly 100% in the 0.5-50 MeV band. At E>100 MeV, the Blazar collective emission, obtained extrapolating their integrated micro-wave flux to the gamma-ray band using the SED of EGRET detected sources, over-predicts the extragalactic background by a large factor, implying that Blazars not only dominate the gamma-ray sky but also that their average duty cycle at these frequencies must be rather low. We also find that Blazars of the HBL type may produce a significant amount of flux at TeV energies.

P. Giommi; S. Colafrancesco; E. Cavazzuti; M. Perri; C. Pittori

2005-08-01T23:59:59.000Z

63

DASI First Results: A Measurement of the Cosmic Microwave Background Angular Power Spectrum  

E-Print Network (OSTI)

We present measurements of anisotropy in the Cosmic Microwave Background (CMB) from the first season of observations with the Degree Angular Scale Interferometer (DASI). The instrument was deployed at the South Pole in the austral summer 1999--2000, and made observations throughout the following austral winter. We have measured the angular power spectrum of the CMB in the range 100foreground templates. We find no evidence of foregrounds other than point sources in the data, and find a maximum likelihood temperature spectral index beta = -0.1 +/- 0.2 (1 sigma), consistent with CMB. We detect a first peak in the power spectrum at l approx 200, in agreement with previous experiments. In addition, we detect a peak in the power spectrum at l approx 550 and power of similar magnitude at l approx 800 which are consistent with the second and third harmonic peaks predicted by adiabatic inflationary cosmological models.

N. W. Halverson; E. M. Leitch; C. Pryke; J. Kovac; J. E. Carlstrom; W. L. Holzapfel; M. Dragovan; J. K. Cartwright; B. S. Mason; S. Padin; T. J. Pearson; M. C. Shepherd; A. C. S. Readhead

2001-04-30T23:59:59.000Z

64

MAR Background Report MAR Background Report: Indigenous Protest in Brazil  

E-Print Network (OSTI)

MAR Background Report MAR Background Report: Indigenous Protest in Brazil Hundreds of indigenous people demonstrated at the National Congress in Brasilia, capital of Brazil, following the announcement in the 1990s in the midst of extensive protests in Brazil and around the world. On February 8, an indigenous

Milchberg, Howard

65

Background  

NLE Websites -- All DOE Office Websites (Extended Search)

Solar panels are designed as a photovoltaic module. The energy producing aspect of the photovoltaic module has two primary steps. The first is a semiconducting material such as...

66

Background  

NLE Websites -- All DOE Office Websites (Extended Search)

and the Bureau of Reclamation signed 10-year agreements - known as the Columbia Basin Fish Accords - with four Northwest tribes and two states on May 2, 2008. These historic...

67

Background  

NLE Websites -- All DOE Office Websites (Extended Search)

maintenance personnel, and film crews use small, portable lighting systems known as "mobile lighting." Traditionally, mobile lighting units are powered by diesel fuel generators...

68

Background  

Science Journals Connector (OSTI)

Onondaga Lake is located (lat. 43°06?54?; long. 76°14?34?) immediately north of the City of Syracuse, in Onondaga County, in the middle of the most urbanized ... River. The Seneca River combines with the Oneida R...

Steven W. Effler; Gena Harnett

1996-01-01T23:59:59.000Z

69

Background  

NLE Websites -- All DOE Office Websites (Extended Search)

Bonneville Power Administration is considering building a new office building on its Ross Complex in Vancouver, Wash., to meet long-standing work space needs. BPA is inviting...

70

Background  

NLE Websites -- All DOE Office Websites (Extended Search)

Administration, January 14, 2011 Figure 2 - Natural Gas Rig Count U.S. Natural Gas Rotary Rigs in Operation (Count) 0 400 800 1200 1600 2000 J a n - 0 7 M a r - 0 7 M a y -...

71

Background  

NLE Websites -- All DOE Office Websites (Extended Search)

Renewable energy sources are critical to the nation's future, and hydrogen-powered fuel cells offer an attractive alternative to current technologies. However, fuel cell...

72

Background  

Office of Scientific and Technical Information (OSTI)

Energy Star Lighting Verification Program (Program for the Evaluation and Analysis of Residential Lighting) Semi-annual report For the period of October 2003 to April 2004 Authored...

73

Background  

NLE Websites -- All DOE Office Websites (Extended Search)

build a facility in the Sandia Science & Technology Park (SS&TP) in 1998 for their Photovoltaics Division, which builds solar cells for the space industry. This division is built...

74

Aluminum as a source of background in low background experiments  

E-Print Network (OSTI)

Neutrinoless double beta decay would be a key to understanding the nature of neutrino masses. The next generation of High Purity Germanium experiments will have to be operated with a background rate of better than 10^-5 counts/(kg y keV) in the region of interest around the Q value of the decay. Therefore, so far irrelevant sources of background have to be considered. The metalization of the surface of germanium detectors is in general done with aluminum. The background from the decays of 22Na, 26Al, 226Ra and 228Th introduced by this metalization is discussed. It is shown that only a special selection of aluminum can keep these background contributions acceptable.

B. Majorovits; I. Abt; M. Laubenstein; O. Volynets

2011-05-18T23:59:59.000Z

75

Low background techniques in XMASS  

SciTech Connect

The XMASS project aims to detect pp and {sup 7}Be solar neutrinos, neutrino-less double beta decay, and dark matter searches using ultra-pure liquid xenon. The first stage of XMASS project is concentrated on dark matter searches using 800 kg liquid xenon detector which requires low background and low threshold. Several techniques applied to XMASS detector for low background will be presented.

Takeda, Atsushi [Kamioka Observatory, ICRR, University of Tokyo, 456 Higashi-Mozumi, Kamioka-cho, Hida, Gifu, 506-1205 (Japan)

2011-04-27T23:59:59.000Z

76

Solar Background Document 3 | Department of Energy  

Energy Savers (EERE)

3 Solar Background Document 3 A list of private sector investment in Solyndra. Solar Background Document 3.pdf More Documents & Publications Solar Background Document 2 GridWise...

77

Integrated global background monitoring network  

SciTech Connect

This paper describes the background and elucidates the need for an integrated global background monitoring network. This network should: establish reference levels for pollutants that have potential for global contaminatin, serve as an early warning site for detecting global spread of pollutants, and establish baseline levels for selected ecosystem parameters against which data from more impacted areas can be compared. This paper proposes the following: (1) establish an integrated global background monitoring network for pollutants and ecosystem parameters; (2) pollutant measurements be multi-media; (3) carry out ecosystem parameter studies in conjunction with pollutant measurements; (4) the network be maintained for an indefinite period of time; (5) the network be established using the international biosphere reserve system as the universe from which a subset of monitoring sites are drawn; and (6) that the project be under the overall direction of the Global Environmental Monitoring System. 43 references, 1 figure, 1 table.

Wiersma, G.B.

1984-08-01T23:59:59.000Z

78

Measurements of the spectral energy distribution of the cosmic infrared background  

E-Print Network (OSTI)

The extragalactic background light (EBL) is the relic emission of all processes of structure formation in the Universe. About half of this background, called the Cosmic Infrared Background (CIB) is emitted in the 8-1000 microns range, and peaks around 150 microns. It is due to the dust reemission from star formation processes and AGN emission. The CIB spectral energy distribution (SED) constraints the models of star formation in the Universe. It is also useful to compute the opacity of the Universe to the TeV photons. We present the different types of measurements of the CIB and discuss their strengths and weaknesses. 1. The absolute SED was measured by COBE, and by other experiments. These measurements are limited by the accuracy of the component separation, i.e. the foreground subtraction. 2. Robust lower limits are determined from the extragalactic number counts of infrared galaxies. These lower limits are very stringent up to 100 microns. At larger wavelengths, the rather low angular resolution of the ins...

Béthermin, Matthieu

2011-01-01T23:59:59.000Z

79

Observations of the Isotropic Diffuse Gamma-ray Background with the EGRET Telescope  

E-Print Network (OSTI)

An Isotropic Diffuse Gamma-Ray Background (IDGRB) in the spectral range 30-10,000 MeV was first reported in the early 1970's using measurements made by the SAS-2 instrument. Data recorded by the Energetic Gamma Ray Experiment Telescope (EGRET) on board the Compton Gamma Ray Observatory (CGRO) over the last 4 years are analysed in order to extract the best measurement yet made of the IDGRB. Extensive analysis of the EGRET instrumental background is presented in order to demonstrate that an uncontaminated data set can be extracted from the EGRET data. A model of the high latitude galactic diffuse foreground emission is presented and the existence of an IDGRB is confirmed. Spatial and spectral analysis of this background is presented. In addition, point source analysis at high galactic latitudes is performed to reveal the existence of a population of extragalactic sources. The characteristics of this population are examined and models of its flux distribution are reported. The question of whether the IDGRB is composed of unresolved point sources is addressed using fluctuation analysis. Finally, possible future directions for gamma ray astronomy are examined through simulations of a future gamma ray telescope: the Gamma-ray Large Area Space Telescope (GLAST). The GLAST baseline design is described and its scientific performance is evaluated. The ability of this telescope to detect 1,000-10,000 new extragalactic sources is demonstrated and the likely impact on the study of the IDGRB is considered.

T. D. Willis

2002-01-30T23:59:59.000Z

80

REFERENCE AND BACKGROUND CHECK PROCESS  

E-Print Network (OSTI)

REFERENCE AND BACKGROUND CHECK PROCESS Workforce Planning | 408-924-2250 classcomp process. Workforce Planning will arrange this directly with the finalist(s) once the hiring manager has provided the finalist(s) name(s) to Workforce Planning. An exception to this process is for any candidates

Su, Xiao

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81

Integrated Global Background Monitoring Network  

SciTech Connect

One of the more significant problems when trying to determine what impact is having on global cycles is not knowing what ''natural'' levels should be for both abiotic (gases, trace elements) and biotic (ecosystem functions) processes. The authors believe that a well designed, coordinated network of baseline stations in remote areas around the world can provide a data base will allow best current estimates to be made of biotic and abiotic baseline conditions. These baseline conditions will then help us make better comparisons with more impacted areas, and thus help us more fully understand the impact man is having on his world. This paper examines the history of background pollution monitoring at the international level, describes current activities in the field of ''integrated'' background monitoring, and proposes criteria for the development of a global network of baseline stations to coordinate background monitoring for the presence, accumulation and behavior of pollutants in remote ecosystems. In this paper, this network is called the Integrated Global Background Monitoring Network.

Wiersma, G.B.; Franklin, J.F.; Kohler, A.; Croze, H.; Boelcke, C.

1986-12-01T23:59:59.000Z

82

A Fast Gridded Method for the Estimation of the Power Spectrum of the CMB from Interferometer Data with Application to the Cosmic Background Imager  

E-Print Network (OSTI)

We describe an algorithm for the extraction of the angular power spectrum of an intensity field, such as the cosmic microwave background (CMB), from interferometer data. This new method, based on the gridding of interferometer visibilities in the aperture plane followed by a maximum likelihood solution for bandpowers, is much faster than direct likelihood analysis of the visibilities, and deals with foreground radio sources, multiple pointings, and differencing. The gridded aperture-plane estimators are also used to construct Wiener-filtered images using the signal and noise covariance matrices used in the likelihood analysis. Results are shown for simulated data. The method has been used to determine the power spectrum of the cosmic microwave background from observations with the Cosmic Background Imager, and the results are given in companion papers.

S. T. Myers; C. R. Contaldi; J. R. Bond; U. -L. Pen; D. Pogosyan; S. Prunet; J. L. Sievers; B. S. Mason; T. J. Pearson; A. C. S. Readhead; M. C. Shepherd

2002-05-23T23:59:59.000Z

83

Emergent Supersymmetry in Warped Backgrounds  

E-Print Network (OSTI)

We show that quantum mechanical supersymmetries are emerged in Kaluza-Klein spectrum of linearized gravity in several warped backgrounds as a consequence of higher-dimensional general coordinate invariance. These emergent supersymmetries play an essential role for the spectral structure of braneworld gravity. We show that for the case of braneworld models with two codimension-1 branes the spectral pattern is completely determined only through the supersymmetries.

Nagasawa, Tomoaki; Sakamoto, Kazuki; Sakamoto, Makoto

2011-01-01T23:59:59.000Z

84

Emergent Supersymmetry in Warped Backgrounds  

E-Print Network (OSTI)

We show that quantum mechanical supersymmetries are emerged in Kaluza-Klein spectrum of linearized gravity in several warped backgrounds as a consequence of higher-dimensional general coordinate invariance. These emergent supersymmetries play an essential role for the spectral structure of braneworld gravity. We show that for the case of braneworld models with two codimension-1 branes the spectral pattern is completely determined only through the supersymmetries.

Tomoaki Nagasawa; Satoshi Ohya; Kazuki Sakamoto; Makoto Sakamoto

2011-05-24T23:59:59.000Z

85

Solar Background Document 6 | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Background Document 6 Graph illustrating solar cell production in the United States and China from 2002 to 2010. Solar Background Document 6.pdf More Documents & Publications Solar...

86

Solar Background Document 1 | Department of Energy  

Energy Savers (EERE)

Solar Background Document 1 Solar Background Document 1 A timeline outlining the Energy Department's extensive review of the Solyndra Solar loan guarantee application from 2006 to...

87

Solar Background Document 5 | Department of Energy  

Energy Savers (EERE)

5 Solar Background Document 5 Graph illustrating Chinese Development Bank financing to Chinese solar companies. Solar Background Document 5.pdf More Documents & Publications Solar...

88

Solar Background Document 6 | Department of Energy  

Energy Savers (EERE)

6 Solar Background Document 6 Graph illustrating solar cell production in the United States and China from 2002 to 2010. Solar Background Document 6.pdf More Documents &...

89

Solar Background Document 2 | Department of Energy  

Energy Savers (EERE)

2 Solar Background Document 2 Media reports and other independent analysts which pointed to Solyndra as a very promising, innovative company. Solar Background Document 2.pdf More...

90

Solar Background Document 4 | Department of Energy  

Energy Savers (EERE)

4 Solar Background Document 4 Graph illustrating global distribution of solar manufacturing market share from 1990 to 2010. Solar Background Document 4.pdf More Documents &...

91

APS USER TRAINING HISTORY Background  

NLE Websites -- All DOE Office Websites (Extended Search)

USER TRAINING HISTORY USER TRAINING HISTORY Background The User Program Division Director has delegated to the CATs the authority to authorize the conduct of experiments because the CATs have accepted responsibility for: * identifying and evaluating the hazards posed by the experiment, * specifying controls appropriate to the hazards, and * verifying that controls are in place. One form of hazard control frequently made mandatory by law and laboratory policy is worker knowledge. The accepted means of verifying that a worker has the required knowledge is ensuring that the worker has completed appropriate training. With CAT input, the APS has developed the APS User Training History. This web-based tool enables designated CAT personnel to examine data characterizing ES&H training courses

92

Gauging the cosmic microwave background  

E-Print Network (OSTI)

We provide a new derivation of the anisotropies of the cosmic microwave background (CMB), and find an exact expression that can be readily expanded perturbatively. Close attention is paid to gauge issues, with the motivation to examine the effect of super-Hubble modes on the CMB. We calculate a transfer function that encodes the behaviour of the dipole, and examine its long-wavelength behaviour. We show that contributions to the dipole from adiabatic super-Hubble modes are strongly suppressed, even in the presence of a cosmological constant, contrary to claims in the literature. We also introduce a naturally defined CMB monopole, which exhibits closely analogous long-wavelength behaviour. We discuss the geometrical origin of this super-Hubble suppression, pointing out that it is a simple reflection of adiabaticity, and hence argue that it will occur regardless of the matter content.

J. P. Zibin; Douglas Scott

2008-12-21T23:59:59.000Z

93

DarkLight radiation backgrounds  

SciTech Connect

We report measurements of photon and neutron radiation levels observed while transmitting a 0.43 MW electron beam through millimeter-sized apertures and during beam-on, but accelerating gradient RF-on, operation. These measurements were conducted at the Free-Electron Laser (FEL) facility of the Jefferson National Accelerator Laboratory (JLab) using a 100 MeV electron beam from an energy-recovery linear accelerator. The beam was directed successively through 6 mm, 4 mm, and 2 mm diameter apertures of length 127 mm in aluminum at a maximum current of 4.3 mA (430 kW beam power). This study was conducted to characterize radiation levels for experiments that need to operate in this environment, such as the proposed DarkLight Experiment. We find that sustained transmission of a 430 kW CW beam through a 2 mm aperture is feasible with manageable beam-related backgrounds. We also find that during beam-off, RF-on operation, field emission inside the niobium cavities of the accelerator cryomodules is the primary source of ambient radiation.

Kalantarians, N. [Department of Physics, Hampton University, Hampton VA 23668 (United States); Collaboration: DarkLight Collaboration

2013-11-07T23:59:59.000Z

94

DarkLight radiation backgrounds  

SciTech Connect

We report measurements of photon and neutron radiation levels observed while transmitting a 0.43 MW electron beam through millimeter-sized apertures and during beam-on, but accelerating gradient RF-on, operation. These measurements were conducted at the Free-Electron Laser (FEL) facility of the Jefferson National Accelerator Laboratory (JLab) using a 100 MeV electron beam from an energy-recovery linear accelerator. The beam was directed successively through 6 mm, 4 mm, and 2 mm diameter apertures of length 127 mm in aluminum at a maximum current of 4.3 mA (430 kW beam power). This study was conducted to characterize radiation levels for experiments that need to operate in this environment, such as the proposed DarkLight Experiment. We find that sustained transmission of a 430 kW CW beam through a 2 mm aperture is feasible with manageable beam-related backgrounds. We also find that during beam-off, RF-on operation, field emission inside the niobium cavities of the accelerator cryomodules is the primary source of ambient radiation.

Kalantarians, Narbe [University of Texas

2013-11-01T23:59:59.000Z

95

Gravitational clustering in Static and Expanding Backgrounds  

E-Print Network (OSTI)

A brief summary of several topics in the study of gravitational many body problem is given. The discussion covers both static backgrounds (applicable to astrophysical systems) as well as clustering in an expanding background (relevant for cosmology)

T. Padmanabhan

2003-08-28T23:59:59.000Z

96

Network Requirements Workshop - Documents and Background Materials  

NLE Websites -- All DOE Office Websites (Extended Search)

Science Requirements Reviews Network Requirements Reviews Documents and Background Materials Science Engagement Move your data Programs & Workshops Science...

97

Risk Estimation; Background Radiation (Natural and Artificial )  

E-Print Network (OSTI)

-threshold mode estimate the response at lower doses. · The Committee on Biological Effects of Ionizing RadiationModule 9 Risk Estimation; Background Radiation (Natural and Artificial ) · sources of background radiation · various risk models. · estimating risk and on the sources of background radiation, both

Massey, Thomas N.

98

TEC Working Group Background | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

TEC Working Group Background TEC Working Group Background TEC Working Group Background Through the TEC/WG, DOE interacted with representatives of organizations at the state, tribal, and local levels to obtain input for program needs assessment, development and management, and to enhance their capability to carry out transportation emergency preparedness and safety activities specifically related to radioactive materials shipments. TEC membership included representatives from national, state, tribal and local government organizations, labor, industry and professional groups. Members meet semiannually to participate in plenary sessions, breakout work sessions, and in more specialized Topic Groups. To learn more about the history and background of TEC, please see the following documents:

99

TEC Working Group Background | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Background Background TEC Working Group Background Through the TEC/WG, DOE interacted with representatives of organizations at the state, tribal, and local levels to obtain input for program needs assessment, development and management, and to enhance their capability to carry out transportation emergency preparedness and safety activities specifically related to radioactive materials shipments. TEC membership included representatives from national, state, tribal and local government organizations, labor, industry and professional groups. Members meet semiannually to participate in plenary sessions, breakout work sessions, and in more specialized Topic Groups. To learn more about the history and background of TEC, please see the following documents: TEC Charter TEC Work Plan

100

LOW INCOME ENERGY EFFICIENCY PROGRAM OVERVIEW Background  

NLE Websites -- All DOE Office Websites (Extended Search)

314 LOW INCOME ENERGY EFFICIENCY PROGRAM OVERVIEW Background BPA's low income program began in 1980, serving the states of Oregon, Montana, Idaho, and Washington. Over time the...

Note: This page contains sample records for the topic "foreground background beaver" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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101

Lighting Choices - White Background | Department of Energy  

Energy Savers (EERE)

the new energy standards that take effect from 2012-2014. allbulbshiresweb.eps More Documents & Publications Lighting Choices - White Background Lighting Choices...

102

Atmospheric muon background in the ANTARES detector  

E-Print Network (OSTI)

An evaluation of the background due to atmospheric muons in the ANTARES high energy neutrino telescope is presented. Two different codes for atmospheric shower simulation have been used. Results from comparisons between these codes at sea level and detector level are presented. The first results on the capability of ANTARES to reject this class of background are given.

S. Cecchini; E. Korolkova; A. Margiotta; L. Thompson

2005-10-28T23:59:59.000Z

103

Background field method as a canonical transformation  

Science Journals Connector (OSTI)

We construct explicitly the canonical transformation which controls the full dependence (local and nonlocal) of the vertex functional of a Yang-Mills theory on a background field. After showing that the canonical transformation found is nothing but a direct field-theoretic generalization of the Lie transform of classical analytical mechanics, we comment on a number of possible applications, and, in particular, the nonperturbative implementation of the background field method on the lattice, the background field formulation of the two-particle irreducible formalism, and, finally, the formulation of the Schwinger-Dyson series in the presence of topologically nontrivial configurations.

D. Binosi and A. Quadri

2012-06-21T23:59:59.000Z

104

Background considerations for SuperCDMS  

SciTech Connect

Rejection and protection from background is a key issue for the next generation SuperCDMS SNOLAB experiment that will have a cross-section sensitivity of better than 8 × 10{sup ?46} cm{sup 2} for spin-independent WIMP-nucleon interactions. This paper presents the details of the methods used to reject electromagnetic backgrounds using the new iZIP detectors that are currently operated in the Soudan Underground Laboratory, MN and the methods the collaboration is investigating to protect against neutron background in the next generation SuperCDMS experiment.

Cooley, J. [Department of Physics, Southern Methodist University, Dallas, TX 75275 (United States)] [Department of Physics, Southern Methodist University, Dallas, TX 75275 (United States); Collaboration: SuperCDMS Collaboration

2013-08-08T23:59:59.000Z

105

LOW INCOME ENERGY EFFICIENCY PROGRAM OVERVIEW Background  

NLE Websites -- All DOE Office Websites (Extended Search)

LOW INCOME ENERGY EFFICIENCY PROGRAM OVERVIEW Background BPA's low income program began in in the mid-80s, serving the states of Oregon, Montana, Idaho, and Washington. Over time...

106

Environmental Permit Application Background Statement (Delaware)  

Energy.gov (U.S. Department of Energy (DOE))

The purpose of Chapter 79 of Delaware Title 7 is to ensure that the State has adequate information about the background of applicants or regulated parties for the purposes of processing permits and...

107

Background Knowledge, Category Labels, and Similarity Judgment  

E-Print Network (OSTI)

are more special than shared physical features. The goal of this dissertation is to provide evidence that complements these conflicting views. I suggest that the role of labels varies depending on the background knowledge: types of categories (living things...

Yu, Na-Yung

2011-10-21T23:59:59.000Z

108

Microsoft Word - Appendix A_Background.doc  

Office of Legacy Management (LM)

Background Information, Remedial Action Histories, Background Information, Remedial Action Histories, Present Site Conditions U.S. Department of Energy Weldon Spring Site LTS&M Plan July 2005 Doc. No. S0079000 Page A-iii Contents A1.1 Location and Property Ownership ................................................................................1 A1.2 Physiography and Topography.....................................................................................4 A1.3 Hydrogeology ...............................................................................................................5 A1.3.1 Regional ...........................................................................................................5 A1.3.2 Chemical Plant .................................................................................................5

109

Preliminary Results from the Cosmic Background Imager  

E-Print Network (OSTI)

The Cosmic Background Imager (CBI) is a 13-element interferometer designed to image intrinsic anisotropies in the cosmic microwave background (CMB) on arcminute scales. A review of the capabilities of the instrument is presented, together with a discussion of observations which have been taken over the past 9 months from the Atacama desert of Chile. We present preliminary high-resolution mosaiced images of the CMB obtained from recent CBI data and discuss topics which the CBI will address in the near future.

B. S. Mason; J. K. Cartwright; S. Padin; T. J. Pearson; A. C. S. Readhead; M. Shepherd; J. Sievers; P. Udomprasert

2001-01-11T23:59:59.000Z

110

Fractal generation of textures and backgrounds  

E-Print Network (OSTI)

FRACTAL GENERATION OF TEXTURES AND BACKGROUNDS A Thesis by KEVIN DUANE REUTER Subtnitted to the Oflice of Graduate Studies of Texas A&M University in partial fulfilhnent of the requirements for the degree of MASTER OF SCIENCE August 1999... Major Subject; Visualization Sciences FRACTAL GENERATION OF TEXTURES AND BACKGROUNDS A Thesis by KEVIN DUANE REUTER Submitted to Texas ARM University in partial fulfilhnent of the requirements for the degree of MASTER OF SCIENCE Approved...

Reuter, Kevin Duane

2012-06-07T23:59:59.000Z

111

Estimating radiological background using imaging spectroscopy  

SciTech Connect

Optical imaging spectroscopy is investigated as a method to estimate radiological background by spectral identification of soils, sediments, rocks, minerals and building materials derived from natural materials and assigning tabulated radiological emission values to these materials. Radiological airborne surveys are undertaken by local, state and federal agencies to identify the presence of radiological materials out of regulatory compliance. Detection performance in such surveys is determined by (among other factors) the uncertainty in the radiation background; increased knowledge of the expected radiation background will improve the ability to detect low-activity radiological materials. Radiological background due to naturally occurring radiological materials (NORM) can be estimated by reference to previous survey results, use of global 40K, 238U, and 232Th (KUT) values, reference to existing USGS radiation background maps, or by a moving average of the data as it is acquired. Each of these methods has its drawbacks: previous survey results may not include recent changes, the global average provides only a zero-order estimate, the USGS background radiation map resolutions are coarse and are accurate only to 1 km – 25 km sampling intervals depending on locale, and a moving average may essentially low pass filter the data to obscure small changes in radiation counts. Imaging spectroscopy from airborne or spaceborne platforms can offer higher resolution identification of materials and background, as well as provide imaging context information. AVIRIS hyperspectral image data is analyzed using commercial exploitation software to determine the usefulness of imaging spectroscopy to identify qualitative radiological background emissions when compared to airborne radiological survey data.

Bernacki, Bruce E.; Schweppe, John E.; Stave, Sean C.; Jordan, David V.; Kulisek, Jonathan A.; Stewart, Trevor N.; Seifert, Carolyn E.

2014-06-13T23:59:59.000Z

112

DOE Hydrogen and Fuel Cells Program: Background  

NLE Websites -- All DOE Office Websites (Extended Search)

Mission and Goals Mission and Goals Organization Chart and Contacts Background U.S. DRIVE Partnership Budget Timeline Program Activities Advisory Panels External Coordination U.S. Department of Energy Search help Home > About > Background Printable Version Background In the early 1970s, concern over our growing dependence on imported petroleum, coupled with concerns about our deteriorating air quality due to emissions from combustion of fossil fuels, spurred the Federal government to act. The timeline below provides policy and programmatic highlights for federally supported hydrogen and fuel cell R&D over the last three decades. Federal Support for Hydrogen and Fuel Cell R&D Some of the following documents are available as Adobe Acrobat PDFs. Download Adobe Reader.

113

National Climate Assessment: Background and Process  

NLE Websites -- All DOE Office Websites (Extended Search)

Background and Process Print E-mail Background and Process Print E-mail Please view the links below to find out more about the background and process of the National Climate Assessment: National Climate Assessment Development & Advisory Committee Charter ( PDF) National Climate Assessment Proposed 2013 Report Outline [updated on 12/08/2011] (PDF) Strategy On May 20th, 2011 the National Climate Assessment released the following two strategy documents: National Climate Assessment Strategy Summary National Climate Assessment Engagement Strategy Federal Register Notices November 18, 2013 National Climate Assessment and Development Advisory Committee (NCADAC) Notice of Open Meeting pdf | html A Notice by the National Oceanic and Atmospheric Administration on 10/29/2013 This notice sets forth the schedule of a forthcoming meeting of the DoC NOAA National Climate Assessment and Development Advisory Committee (NCADAC).

114

Monitored Retrievable Storage Background | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Monitored Retrievable Storage Background Monitored Retrievable Storage Background Monitored Retrievable Storage Background `The U.S. Government is seeking a site for a monitored retrievable storage facility (MRS). Employing proven technologies used in this country and abroad, the MRS will be an Integral part of the Federal system for safe and permanent disposal of the nation's high-level radioactive wastes. The MRS will accept shipments of spent fuel from commercial nuclear power plants, temporarily store the spent fuel above ground, and stage shipments of it to a geologic repository for permanent disposal. The law authorizing the MRS provides an opportunity for a State or an Indian Tribe to volunteer to host the MRS. The law establishes the Office of the Nuclear Waste Negotiator, who Is 10 seek a State or an Indian Tribe

115

Cosmological origin of anomalous radio background  

SciTech Connect

The ARCADE 2 collaboration has reported a significant excess in the isotropic radio background, whose homogeneity cannot be reconciled with clustered sources. This suggests a cosmological origin prior to structure formation. We investigate several potential mechanisms and show that injection of relativistic electrons through late decays of a metastable particle can give rise to the observed excess radio spectrum through synchrotron emission. However, constraints from the cosmic microwave background (CMB) anisotropy, on injection of charged particles and on the primordial magnetic field, present a challenge. The simplest scenario is with a ?>9 GeV particle decaying into e{sup +}e{sup ?} at a redshift of z ? 5, in a magnetic field of ? 5?G, which exceeds the CMB B-field constraints, unless the field was generated after decoupling. Decays into exotic millicharged particles can alleviate this tension, if they emit synchroton radiation in conjunction with a sufficiently large background magnetic field of a dark U(1)' gauge field.

Cline, James M. [Department of Physics, McGill University, 3600 Rue University, Montréal, Québec, H3A 2T8 Canada (Canada); Vincent, Aaron C., E-mail: jcline@physics.mcgill.ca, E-mail: vincent@ific.uv.es [Instituto de Física Corpuscular, Universitat de València - CSIC, 46071, Valencia (Spain)

2013-02-01T23:59:59.000Z

116

Cosmic Microwave Background Tests of Inflation  

E-Print Network (OSTI)

Inflation provides a unified paradigm for understanding the isotropy of the cosmic microwave background (CMB), the flatness problem, and the origin of large-scale structure. Although the physics responsible for inflation is not yet well understood, slow-roll inflation generically makes several predictions: a flat Universe, primordial adiabatic density perturbations, and a stochastic gravity-wave background. Inflation further predicts specific relations between the amplitudes and shapes of the spectrum of density perturbations and gravity waves. There are now excellent prospects for testing precisely these predictions with forthcoming CMB temperature and polarization maps. Here I discuss these new CMB tests of inflation.

Marc Kamionkowski

1998-03-14T23:59:59.000Z

117

Beaver MCCs and Switchgear  

NLE Websites -- All DOE Office Websites (Extended Search)

Little Rock District Little Rock District MCC's and Switchgear Replacement Project The Following photo's list typical damage and faults of existing equipment Customer Funding 2014 480V Station Service Switchgear Currently the switchyard has only one available feeder. The shown AK 30 breaker is obsolete and needs repairs. Similar with other Breakers. Breakers have to be swapped to place parallel feeders into service. Motor Generator MCC This Center contains the DC generator and battery chargers. Most of the scavenged parts have been taken here to keep this gear as complete as possible. See notes Unit 1 Distribution MCC Parts have been removed to keep other circuits in service. Unable to get replacement parts Motor control centers are obsolete. We have to do unacceptable

118

Survey Background and Technical Information on CBECS  

U.S. Energy Information Administration (EIA) Indexed Site

Survey Background and Technical Information Survey Background and Technical Information Survey Background and Technical Information Survey Background The commercial sector encompasses a vast range of building types- service businesses, such as retail and wholesale stores, hotels and motels, restaurants, and hospitals, as well as certain buildings that would not be considered "commercial" in a traditional economic sense, such as public and private schools, correctional institutions, and religious and fraternal organizations. Excluded from the sector are the goods-producing industries: manufacturing, agriculture, mining, forestry and fisheries, and construction. Nearly all energy use in the commercial sector takes place in, or is associated with, the buildings that house these commercial activities. Analysis of the structures, activities, and equipment associated with different types of buildings is the clearest way to evaluate commercial sector energy use. The Commercial Buildings Energy Consumption Survey (CBECS) is a national-level sample survey of commercial buildings and their energy suppliers conducted quadrennially (previously triennially) by the Energy Information Administration (EIA). The 2003 CBECS was the eighth survey in the series begun in 1979. From 1979 to 1986, the survey was known as the Nonresidential Buildings Energy Consumption Survey, or NBECS.

119

Background Simulations for the International Linear Collider  

E-Print Network (OSTI)

on superconducting technology to collide bunches of electrons and positrons. The baseline configuration (about 31 km in a clean experimental environment with low backgrounds. The LHC will likely discover the Higgs boson accelerator directly. DESY FLC, 22603 Hamburg, Germany, adrian.vogel@desy.de 1 #12;Figure 1: Overall view

120

CHAPTER 1 INTRODUCTION 1.1 Background  

E-Print Network (OSTI)

1 CHAPTER 1 INTRODUCTION 1.1 Background This thesis describes a multi-agent based architecture of the research and an outline plan for the rest of this thesis complete the chapter. 1.2 Software Project and monitor progress to check the development is on time and within budget. #12;3 1.3 Software Project

O'Connor, Rory

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While these samples are representative of the content of NLEBeta,
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We encourage you to perform a real-time search of NLEBeta
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121

1 Introduction 1.1 Background  

E-Print Network (OSTI)

#12;#12;3 1 Introduction 1.1 Background Research method is a relevant topic to anybody performing. 1.2 Classical Research, Technology and Technology Research The term research is defined in several different ways. According to Merriam-Webster [1], research is "investigation or experimentation aimed

Stølen, Ketil

122

Internships at VSTEP BV Background VSTEP  

E-Print Network (OSTI)

, the effect of the current on the ship's manoeuvring characteristics needs to be implemented. 5. A damage (www.quest3d.com) and C++. Background Ship Simulator 2006 One of VSTEP's more recent products is a PC game called Ship Simulator 2006 (www.shipsim.com), in store in many countries since June 2006

Vuik, Kees

123

Carbon Management and Implementation Plan 1. Background  

E-Print Network (OSTI)

the College's energy efficiency and use of resources by integrating sustainability with corporate strategiesCarbon Management and Implementation Plan 1. Background Energy security and the increasing concentration of greenhouse gases which contribute to climate change are one of the biggest challenges facing us

Chittka, Lars

124

Background estimation using a robust Bayesian analysis  

Science Journals Connector (OSTI)

A novel method for the estimation of the background in a powder diffraction pattern has been developed using a robust Bayesian analysis. The underlying probability theory is discussed in terms of going beyond the Gaussian approximation normally associated with counting statistics and least-squares analysis, and various examples are presented that illustrate the general applicability of the approach.

David, W.I.F.

2001-05-22T23:59:59.000Z

125

UCHC Lockout/Tagout Policy Background  

E-Print Network (OSTI)

UCHC Lockout/Tagout Policy (4/09) Background: This safety policy is applicable to all Health Center: Lockout will be utilized for equipment which is designed with a lockout capability. A valve that can be locked out with a chain is considered as having a lockout capability. Only the Office of Research Safety

Kim, Duck O.

126

Cosmic IR Backgrounds Ned Wright (UCLA)  

E-Print Network (OSTI)

Cosmic IR Backgrounds by Ned Wright (UCLA) http://www.astro.ucla.edu/~wright/intro.html See: · http://www.astro.ucla.edu/~wright/cosmolog.htm · http://www.astro.ucla.edu/~wright/DIRBE · http://www.astro.ucla.edu/~wright/CIBR · http

Wright, Edward L. "Ned"

127

Background Material Important Questions about Magnetism  

E-Print Network (OSTI)

Background Material Important Questions about Magnetism: 1) What is Magnetism?Magnetism is a force or repulsion due to charge is called the electric force. But what about magnetism, is there a fundamental property of some matter that makes things magnetic? The answer is: "sort of." Electric current

Mojzsis, Stephen J.

128

First National Climate Assessment: Background and Process  

NLE Websites -- All DOE Office Websites (Extended Search)

Background and Process Print E-mail Background and Process Print E-mail Workshops of the First National Climate Assessment In February 1997, the U.S. Global Change Research Program and the Office of Science and Technology Policy initiated a series of Regional Climate Change Workshops with the goal of starting the process of examining the vulnerabilities of regions of the United States to climate variability and climate change. What was initially intended to be three or four workshops developed into a series of twenty, covering every state and territory of the United States. The workshops span from May 1997 to September 1998 and represented the first step in conducting a regional assessment. Each workshop was sponsored by one or more government agencies,and was carried out by coordinators from local institutions. For details on each workshop, including its geographic coverage, see:

129

Polarization Observations with the Cosmic Background Imager  

E-Print Network (OSTI)

Polarization observations of the cosmic microwave background with the Cosmic Background Imager from September 2002 to May 2004 provide a significant detection of the E-mode polarization and reveal an angular power spectrum of polarized emission showing peaks and valleys that are shifted in phase by half a cycle relative to those of the total intensity spectrum. This key agreement between the phase of the observed polarization spectrum and that predicted based on the total intensity spectrum provides support for the standard model of cosmology, in which dark matter and dark energy are the dominant constituents, the geometry is close to flat, and primordial density fluctuations are predominantly adiabatic with a matter power spectrum commensurate with inflationary cosmological models.

A. C. S. Readhead; S. T. Myers; T. J. Pearson; J. L. Sievers; B. S. Mason; C. R. Contaldi; J. R. Bond; R. Bustos; P. Altamirano; C. Achermann; L. Bronfman; J. E. Carlstrom; J. K. Cartwright; S. Casassus; C. Dickinson; W. L. Holzapfel; J. M. Kovac; E. M. Leitch; J. May; S. Padin; D. Pogosyan; M. Pospieszalski; C. Pryke; R. Reeves; M. C. Shepherd; S. Torres

2004-09-23T23:59:59.000Z

130

Sideband Mixing in Intense Laser Backgrounds  

E-Print Network (OSTI)

The electron propagator in a laser background has been shown to be made up of a series of sideband poles. In this paper we study this decomposition by analysing the impact of the residual gauge freedom in the Volkov solution on the sidebands. We show that the gauge transformations do not alter the location of the poles. The identification of the propagator from the two-point function is maintained but we show that the sideband structures mix under residual gauge transformations.

Martin Lavelle; David McMullan

2014-07-04T23:59:59.000Z

131

Cosmic Microwave Background: Past, Future, and Present  

E-Print Network (OSTI)

I explain the origin and evolution of anisotropies in the Cosmic Microwave Background (CMB) and argue that upcoming experiments will measure cosmological and fundamental parameters very accurately. Most of the paper focuses on present data, which strongly suggest that the universe is flat. Several arguments are given to prove that present data sets are not contaminated by systematics. New techniques to compare different experiments visually are introduced. These are illustrated for two years of the MSAM and Python experiments.

Scott Dodelson

1999-12-22T23:59:59.000Z

132

Higher-order gravitational perturbations of the cosmic microwave background  

Science Journals Connector (OSTI)

We study the behavior of light rays in perturbed Robertson-Walker cosmologies, calculating the redshift between an observer and the surface of last scattering to second order in the metric perturbation. At first order we recover the classic results of Sachs and Wolfe, and at second order we delineate the various new effects which appear; there is no a priori guarantee that these effects are significantly smaller than those at first order, since there are large length scales in the problem which could lead to sizable prefactors. We find that secondorder terms of potential observational interest may be interpreted as transverse and longitudinal lensing by foreground density perturbations, and a correction to the integrated Sachs-Wolfe effect.

Ted Pyne and Sean M. Carroll

1996-03-15T23:59:59.000Z

133

Higher-Order Gravitational Perturbations of the Cosmic Microwave Background  

E-Print Network (OSTI)

We study the behavior of light rays in perturbed Robertson-Walker cosmologies, calculating the redshift between an observer and the surface of last scattering to second order in the metric perturbation. At first order we recover the classic results of Sachs and Wolfe, and at second order we delineate the various new effects which appear; there is no {\\it a priori} guarantee that these effects are significantly smaller than those at first order, since there are large length scales in the problem which could lead to sizable prefactors. We find that second order terms of potential observational interest may be interpreted as transverse and longitudinal lensing by foreground density perturbations, and a correction to the integrated Sachs-Wolfe effect.

Ted Pyne; Sean M. Carroll

1995-12-07T23:59:59.000Z

134

Hanford Site background: Part 1, Soil background for nonradioactive analytes. Revision 1, Volume 1  

SciTech Connect

The determination of soil background is one of the most important activities supporting environmental restoration and waste management on the Hanford Site. Background compositions serve as the basis for identifying soil contamination, and also as a baseline in risk assessment processes used to determine soil cleanup and treatment levels. These uses of soil background require an understanding of the extent to which analytes of concern occur naturally in the soils. This report documents the results of sampling and analysis activities designed to characterize the composition of soil background at the Hanford Site, and to evaluate the feasibility for use as Sitewide background. The compositions of naturally occurring soils in the vadose Zone have been-determined for-nonradioactive inorganic and organic analytes and related physical properties. These results confirm that a Sitewide approach to the characterization of soil background is technically sound and is a viable alternative to the determination and use of numerous local or area backgrounds that yield inconsistent definitions of contamination. Sitewide soil background consists of several types of data and is appropriate for use in identifying contamination in all soils in the vadose zone on the Hanford Site. The natural concentrations of nearly every inorganic analyte extend to levels that exceed calculated health-based cleanup limits. The levels of most inorganic analytes, however, are well below these health-based limits. The highest measured background concentrations occur in three volumetrically minor soil types, the most important of which are topsoils adjacent to the Columbia River that are rich in organic carbon. No organic analyte levels above detection were found in any of the soil samples.

Not Available

1993-04-01T23:59:59.000Z

135

DOE Vendor Communication Plan I. Background  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Vendor Communication Plan Vendor Communication Plan I. Background On February 2, 2011, the Office of Federal Procurement Policy (OFPP) issued a memorandum entitled "Myth-Busting: Addressing Misconceptions to Improve Communication with Industry during the Acquisition Process." In addition to identifying and refuting common misconceptions about vendor engagement, the memorandum directed agencies to develop high-level vendor communication plans to discuss how each agency will reduce unnecessary barriers, publicize communication opportunities, and prioritize engagement opportunities for high-risk, complex programs or those that fail to attract new vendors during re-competitions.

136

New physics from the Cosmic Microwave Background  

E-Print Network (OSTI)

I review the present status of the Cosmic Microwave Background, with some emphasis on the current and future implications for particle physics. Conclusions are: gravitational instability in a dark matter dominated universe grew today's structure; the Universe remained neutral until z<~50; the CMB power spectrum peaks at 150<~l<~350; the large-scale structure of spacetime appears to be simple; something like inflation is something like proven; we will learn a great deal about cosmology, astrophysics and particle physics from MAP and Planck.

Douglas Scott

1999-11-17T23:59:59.000Z

137

../fusion/templates/mapguide/maroon/css/maroon_fusion.css background-image: url(../images/background.gif);  

E-Print Network (OSTI)

../fusion/templates/mapguide/maroon/css/maroon_fusion.css body { background-image: url(../images/background.gif); ../fusion/templates/mapguide/maroon/css/ maroon_fusion.css body { background-color: #3e5c5f; ../fusion/templates/mapguide/maroon/css/ maroon_fusion.css #ToolbarVertical { background: #500000; maroon_fusion.css #Toolbar { background

Ahmad, Sajjad

138

Notices Background The National Wildlife Refuge System  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

89 Federal Register 89 Federal Register / Vol. 74, No. 223 / Friday, November 20, 2009 / Notices Background The National Wildlife Refuge System Administration Act of 1966 (16 U.S.C. 668dd-668ee) (Administration Act), as amended by the National Wildlife Refuge System Improvement Act of 1997, requires us to develop a CCP for each national wildlife refuge. The purpose for developing a CCP is to provide refuge managers with a 15-year plan for achieving refuge purposes and contributing toward the mission of the National Wildlife Refuge System, consistent with sound principles of fish and wildlife management, conservation, legal mandates, and our policies. In addition to outlining broad management direction on conserving wildlife and their habitats, CCPs identify wildlife-

139

Anisotropies in the Cosmic Microwave Background: Theory  

E-Print Network (OSTI)

Anisotropies in the Cosmic Microwave Background (CMB) contain a wealth of information about the past history of the universe and the present values of cosmological parameters. I ouline some of the theoretical advances of the last few years. In particular, I emphasize that for a wide class of cosmological models, theorists can accurately calculate the spectrum to better than a percent. The specturm of anisotropies today is directly related to the pattern of inhomogeneities present at the time of recombination. This recognition leads to a powerful argument that will enable us to distinguish inflationary models from other models of structure formation. If the inflationary models turn out to be correct, the free parameters in these models will be determined to unprecedented accuracy by the upcoming satellite missions.

Scott Dodelson

1997-02-14T23:59:59.000Z

140

Fast neutron background measurements at shallow depths  

SciTech Connect

We report on measurements of the neutron backgrounds for neutrino experiments at shallow depth (such as the proposed San Onofre neutrino oscillation experiment). A detector capable of pulse-shape discrimination measured the flux of fast neutrons at 20 mwe depth in the Stanford Underground Facility to be (1.07 {+-} 0.30) X 10{sup -6} cm{sup -2} s{sup -1}. An experiment, situated in the Tendon Gallery of the San Onofre Unit 2 reactor. studied spallation neutrons from muons traversing Pb and Cu. An underground experiment in the SUF, employing a detector filled with Gd-loaded liquid scintillator, is measuring the neutron production rate and multiplicity for muon spallation in low-A material (hydrocarbon-based liquid scintillator).

Chen, M.; Hertenberger, R.; Novikov, V. [Inst. of Nuclear Research, Moscow (Russian Federation); Dougherty, B.

1993-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "foreground background beaver" from the National Library of EnergyBeta (NLEBeta).
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141

Information Gains from Cosmic Microwave Background Experiments  

E-Print Network (OSTI)

To shed light on the fundamental problems posed by Dark Energy and Dark Matter, a large number of experiments have been performed and combined to constrain cosmological models. We propose a novel way of quantifying the information gained by updates on the parameter constraints from a series of experiments which can either complement earlier measurements or replace them. For this purpose, we use the Kullback-Leibler divergence or relative entropy from information theory to measure differences in the posterior distributions in model parameter space from a pair of experiments. We apply this formalism to a historical series of Cosmic Microwave Background experiments ranging from Boomerang to WMAP, SPT, and Planck. Considering different combinations of these experiments, we thus estimate the information gain in units of bits and distinguish contributions from the reduction of statistical errors and the `surprise' corresponding to a significant shift of the parameters' central values. For this experiment series, we...

Seehars, Sebastian; Refregier, Alexandre; Paranjape, Aseem; Akeret, Joël

2014-01-01T23:59:59.000Z

142

The Cosmic Microwave Background and Particle Physics  

E-Print Network (OSTI)

In forthcoming years, connections between cosmology and particle physics will be made increasingly important with the advent of a new generation of cosmic microwave background (CMB) experiments. Here, we review a number of these links. Our primary focus is on new CMB tests of inflation. We explain how the inflationary predictions for the geometry of the Universe and primordial density perturbations will be tested by CMB temperature fluctuations, and how the gravitational waves predicted by inflation can be pursued with the CMB polarization. The CMB signatures of topological defects and primordial magnetic fields from cosmological phase transitions are also discussed. Furthermore, we review current and future CMB constraints on various types of dark matter (e.g. massive neutrinos, weakly interacting massive particles, axions, vacuum energy), decaying particles, the baryon asymmetry of the Universe, ultra-high-energy cosmic rays, exotic cosmological topologies, and other new physics.

Marc Kamionkowski; Arthur Kosowsky

1999-04-09T23:59:59.000Z

143

Schwarzschild black hole in dark energy background  

E-Print Network (OSTI)

In this paper we present an exact solution of Einstein's field equations describing the Schwarzschild black hole in dark energy background. It is also regarded as an embedded solution that the Schwarzschild black hole is embedded into the dark energy space producing Schwarzschild-dark energy black hole. It is found that the space-time geometry of Schwarzschild-dark energy solution is non-vacuum Petrov type $D$ in the classification of space-times. We study the energy conditions (like weak, strong and dominant conditions) for the energy-momentum tensor of the Schwarzschild-dark energy solution. We also find that the energy-momentum tensor of the Schwarzschild-dark energy solution violates the strong energy condition due to the negative pressure leading to a repulsive gravitational force of the matter field in the space-time. It is shown that the time-like vector field for an observer in the Schwarzschild-dark energy space is expanding, accelerating, shearing and non-rotating. We investigate the surface gravity and the area of the horizons for the Schwarzschild-dark energy black hole.

Ngangbam Ishwarchandra; Ng. Ibohal; K. Yugindro Singh

2014-09-27T23:59:59.000Z

144

Statistics of Cosmic Microwave Background Polarization  

E-Print Network (OSTI)

We present a formalism for analyzing a full-sky temperature and polarization map of the cosmic microwave background. Temperature maps are analyzed by expanding over the set of spherical harmonics to give multipole moments of the two-point correlation function. Polarization, which is described by a second-rank tensor, can be treated analogously by expanding in the appropriate tensor spherical harmonics. We provide expressions for the complete set of temperature and polarization multipole moments for scalar and tensor metric perturbations. Four sets of multipole moments completely describe isotropic temperature and polarization correlations; for scalar metric perturbations one set is identically zero, giving the possibility of a clean determination of the vector and tensor contributions. The variance with which the multipole moments can be measured in idealized experiments is evaluated, including the effects of detector noise, sky coverage, and beam width. Finally, we construct coordinate-independent polarization two-point correlation functions, express them in terms of the multipole moments, and derive small-angle limits.

Marc Kamionkowski; Arthur Kosowsky; Albert Stebbins

1996-11-15T23:59:59.000Z

145

Building Technologies Office: Home Energy Score Research and Background  

NLE Websites -- All DOE Office Websites (Extended Search)

Research and Background to someone by E-mail Research and Background to someone by E-mail Share Building Technologies Office: Home Energy Score Research and Background on Facebook Tweet about Building Technologies Office: Home Energy Score Research and Background on Twitter Bookmark Building Technologies Office: Home Energy Score Research and Background on Google Bookmark Building Technologies Office: Home Energy Score Research and Background on Delicious Rank Building Technologies Office: Home Energy Score Research and Background on Digg Find More places to share Building Technologies Office: Home Energy Score Research and Background on AddThis.com... About Take Action to Save Energy Partner With DOE Activities Solar Decathlon Building America Home Energy Score Get Involved Partners Research & Background

146

Loops and spurs: the angular power spectrum of the Galactic synchrotron background  

SciTech Connect

We present a new model of the diffuse Galactic synchrotron radiation, concentrating on its angular anisotropies. While previous studies have focussed on either the variation of the emissivity on large ( ? kpc) scales, or on fluctuations due to MHD turbulence in the interstellar medium, we unify these approaches to match the angular power spectrum. We note that the usual turbulence cascade calculation ignores spatial correlations at the injection scale ( ? 100 pc) due to compression of the interstellar medium by of O(1000) old supernova remnants — the 'radio loops' only four of which are visible in radio maps. This new component naturally provides the otherwise missing power on intermediate and small scales in the all-sky map at 408 MHz. Our model can enable more reliable subtraction of the synchrotron foreground for studies of CMB anisotropies or searches for dark matter annihilation. We conclude with some remarks on the relevance to modelling of the polarised foreground.

Mertsch, Philipp [Kavli Institute for Particle Astrophysics and Cosmology, 2575 Sand Hill Road, M/S 29, Menlo Park, CA 94025 (United States); Sarkar, Subir, E-mail: pmertsch@stanford.edu, E-mail: sarkar@nbi.dk [Rudolf Peierls Centre for Theoretical Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP (United Kingdom)

2013-06-01T23:59:59.000Z

147

Evidence-Based Background Material Underlying Guidance for Federal...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Material Underlying Guidance for Federal Agencies in Implementing Strategic Sustainability Performance Plans Evidence-Based Background Material Underlying Guidance for...

148

Muon-induced backgrounds in the CUORICINO experiment  

E-Print Network (OSTI)

background in the neutrinoless double beta decay region ofis searching for neutrinoless double beta decay (0???), a

Andreotti, E.

2010-01-01T23:59:59.000Z

149

Surface-wave-enabled darkfield aperture for background suppression during  

E-Print Network (OSTI)

can be directly incorporated onto optical sensors to accom- plish predetection background suppression if the sensor is fully capable of measuring the same weak signal in the absence of background (1, 2- trivial to employ. A sensor that can intrinsically cancel a strong background prior to signal detection

Yang, Changhuei

150

PoGOLite: Neutron Background Studies for High Latitudes  

E-Print Network (OSTI)

PoGOLite: Neutron Background Studies for High Latitudes Maria Fernanda Muñoz Salinas SH2006. The measurements showed a neutron background ten times higher than expected. Because of this, new simulations of the PoGOLite flight which will take place in the summer of 2012. The neutron background was simulated

Haviland, David

151

Matrix Model in a Class of Time Dependent Supersymmetric Backgrounds  

E-Print Network (OSTI)

We discuss the matrix model in a class of 11D time dependent supersymmetric backgrounds as obtained in hep-th/0508191 . We construct the matrix model action through the matrix regularization of the membrane action in the background. We show that the action is exact to all order of fermionic coordinates. Furthermore We discuss the fuzzy sphere solutions in this background.

Hong-Zhi Chen; Bin Chen

2006-03-19T23:59:59.000Z

152

Role of Background in the CERCLA Cleanup Program  

NLE Websites -- All DOE Office Websites (Extended Search)

Background in the CERCLA Cleanup Program Background in the CERCLA Cleanup Program U.S. Environmental Protection Agency Office of Solid Waste and Emergency Response Office of Emergency and Remedial Response April 26, 2002 OSWER 9285.6-07P OSWER 9285.6-07P page 2 of 13 Table of Contents Purpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 3 of 13 History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 4 of 13 Definitions of Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 5 of 13 Consideration of Background in Risk Assessment . . . . . . . . . . . . . . . . . . . . . . . . . . Page 6 of 13 Consideration of Background in Risk Management . . . . . . . . . . . . . . . . . . . . . . . . . Page 7 of 13 Consideration of Background in Risk Communication . . . . . . . . . . . . . . . . . . . . . . . Page 8 of 13 Hypothetical Case Examples .

153

Microsoft PowerPoint - Powerpoint_Background.ppt [Compatibility Mode]  

NLE Websites -- All DOE Office Websites (Extended Search)

g g Radiation Radiation Radiation is everywhere Cosmic Inhaled Radon Inhaled Radon Bodies Plants Bodies Radioactive Elements We live in a sea of radiation... Rocks BACKGROUND RADIATION BACKGROUND RADIATION The average background radiation per person is 370 millirems per person is 370 millirems (mrem) per year. This varies widely depending on where someone lives and their someone lives, and their occupation, health and lifestyle. Background Radiation g Most background radiation is g natural. It is part of nat re It is part of nature. It has always been here. y People have always lived with it. Radiation comes from space- sun and cosmic rays Because this type of radiation is somewhat shielded by the atmosphere, y p the dose is higher at higher altitudes Background Radiation Exposure at Different Elevations

154

Overcoming High Energy Backgrounds at Pulsed Spallation Sources  

E-Print Network (OSTI)

Instrument backgrounds at neutron scattering facilities directly affect the quality and the efficiency of the scientific measurements that users perform. Part of the background at pulsed spallation neutron sources is caused by, and time-correlated with, the emission of high energy particles when the proton beam strikes the spallation target. This prompt pulse ultimately produces a signal, which can be highly problematic for a subset of instruments and measurements due to the time-correlated properties, and different to that from reactor sources. Measurements of this background have been made at both SNS (ORNL, Oak Ridge, TN, USA) and SINQ (PSI, Villigen, Switzerland). The background levels were generally found to be low compared to natural background. However, very low intensities of high-energy particles have been found to be detrimental to instrument performance in some conditions. Given that instrument performance is typically characterised by S/N, improvements in backgrounds can both improve instrument pe...

Cherkashyna, Nataliia; DiJulio, Douglas D; Khaplanov, Anton; Pfeiffer, Dorothea; Scherzinger, Julius; Cooper-Jensen, Carsten P; Fissum, Kevin G; Ansell, Stuart; Iverson, Erik B; Ehlers, Georg; Gallmeier, Franz X; Panzner, Tobias; Rantsiou, Emmanouela; Kanaki, Kalliopi; Filges, Uwe; Kittelmann, Thomas; Extegarai, Maddi; Santoro, Valentina; Kirstein, Oliver; Bentley, Phillip M

2015-01-01T23:59:59.000Z

155

The Killing superalgebra of ten-dimensional supergravity backgrounds  

E-Print Network (OSTI)

We construct the Killing superalgebra of supersymmetric backgrounds of ten-dimensional heterotic and type II supergravities and prove that it is a Lie superalgebra. We also show that if the fraction of supersymmetry preserved by the background is greater than 1/2, in the heterotic case, or greater than 3/4 in the type II case, then the background is locally homogeneous.

José Figueroa-O'Farrill; Emily Hackett-Jones; George Moutsopoulos

2007-03-21T23:59:59.000Z

156

Smoothing of the cosmic background radiation by multiple gravitational scattering  

Science Journals Connector (OSTI)

We investigated the smoothing of the cosmic background radiation (CBR) ... rays increases exponentially through multiple scatterings. This exponential growth occurs if the distance is smaller...

Junichiro Making

1994-01-01T23:59:59.000Z

157

Backgrounds and Projected Limits from Dark Matter Direct Detection Experiments  

E-Print Network (OSTI)

A simple formula is introduced which indicates the amount by which projections of dark matter direct detection experiments are expected to be degraded due to backgrounds.

Scott Dodelson

2008-12-08T23:59:59.000Z

158

ESnet supports Sandia and APNIC IPv6 Background Radiation research  

NLE Websites -- All DOE Office Websites (Extended Search)

supports Sandia and APNIC IPv6 Background Radiation research Engineering Services The Network OSCARS Fasterdata IPv6 Network IPv6 Implementation Checklist ESnet IPv6 Mirror Servers...

159

Muon-induced backgrounds in the CUORICINO experiment  

E-Print Network (OSTI)

Muon-induced backgrounds in the CUORICINO experiment E.the contribution of cosmic ray muons to the CUORICINOKey words: CUORICINO, muons, cosmic rays, double beta decay,

Andreotti, E.

2010-01-01T23:59:59.000Z

160

An electronic radiation of blackbody: Cosmic electron background  

E-Print Network (OSTI)

The Universe owns the electronic radiation of blackbody at temperature 2.725 K, which we call the cosmic electron background. We calculate its radiation spectrum. The energy distribution of number density of electrons in the cosmic electron background becomes zero as energy goes to both zero and infinity. It has one maximum peak near the energy level of 10**(-23) J.

Jian-Miin Liu

2008-02-23T23:59:59.000Z

Note: This page contains sample records for the topic "foreground background beaver" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Background Long history of research and education in "nuclear  

E-Print Network (OSTI)

· Degradation Nuclear Materials · Multi physics modelling · Severe nuclear accidents · Non destructive testing#12;Background · Long history of research and education in "nuclear engineering" at Chalmers. · "Nuclear engineering" = multi-disciplinary research area. #12;Background Establishment of the Sustainable

Lemurell, Stefan

162

cognitive backgroundCIS4140-2 1 administrivia  

E-Print Network (OSTI)

Cognitive background human-computer interaction understand computer workings (reasonably well) how about humans? once part of psychology now considered cognitive science may also need some sociology later #12;cognitive backgroundCIS4140-2 4 perceptual 2 perceptions considered for UI auditory visual new interfaces

Damon, Craig A.

163

Low Background Radiation Experiment Yields Interesting Preliminary Results  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Low Background Radiation Experiment Yields Interesting Preliminary Low Background Radiation Experiment Yields Interesting Preliminary Results Low Background Radiation Experiment Yields Interesting Preliminary Results May 18, 2011 - 12:00pm Addthis Media Contact Deb Gill U.S. DOE Carlsbad Field Office (575) 234-7270 CARLSBAD, N.M. - New Mexico State University"s Low Background Radiation Experiment (LBRE), which takes place 2,150 feet below the earth"s surface at the Waste Isolation Pilot Plant, recently released some results about the project"s first two years of experimentation. The March 2011 edition of Health Physics printed an article titled "Exploring Biological Effects of Low Level Radiation from the Other Side of Background," summarizing some initial data taken from LBRE and from a sister experiment conducted at the Lovelace Respiratory Research Institute

164

Spinning Test Particle in Kalb-Ramond background  

E-Print Network (OSTI)

In this work we explore the geodesic deviations of spinning test particles in a string inspired Einstein-Kalb Ramond background. Such a background is known to be equivalent to a spacetime geometry with torsion. We have shown here that the antisymmetric Kalb-Ramond field has significant effect on the geodesic deviation of a spinning test particle. A search for an observational evidence of such an effect in astrophysical experiments may lead to a better undestanding of the geometry of the background spacetime.

Debaprasad Maity; Soumitra SenGupta; Sourav Sur

2005-05-19T23:59:59.000Z

165

Sakai-Sugimoto model in D0-D4 background  

Science Journals Connector (OSTI)

We add smeared D0 charges to the D4 background and discuss the Sakai-Sugimoto model under this background. The corresponding gauge theory is in a state with an expectation value of ?tr(F??F˜??)?. The D8-branes go less deep than in the original S-S model and massless Goldstones are still found in the spectrum. The effects of this condensate on the meson spectra, pion decay constant, and couplings of the vector mesons and Goldstones in this background state are then investigated.

Chao Wu; Zhiguang Xiao; Da Zhou

2013-07-22T23:59:59.000Z

166

Background gamma terrestrial dose rate in Nigerian functional coal mines  

Science Journals Connector (OSTI)

......444-448 (2003). 12. Nakaoka, A., Fukushima, M. and Shinji, T. Environmental...TERRESTRIAL DOSE RATE IN NIGERIAN MINES N d Aerial ropeway Figure 2. Surface background...444 448 (2003). 12. Nakaoka, A., Fukushima, M. and Shinji, T. Environmental......

C. E. Mokobia; F. A. Balogun

2004-01-01T23:59:59.000Z

167

EXTRAGALACTIC VERY HIGH ENERGY GAMMA-RAY BACKGROUND  

SciTech Connect

We study the origin of the extragalactic diffuse gamma-ray background using the data from the Fermi telescope. To estimate the background level, we count photons at high Galactic latitudes |b| > 60 Degree-Sign . Subtracting photons associated with known sources and the residual cosmic-ray and Galactic diffuse backgrounds, we estimate the extragalactic gamma-ray background (EGB) flux. We find that the spectrum of EGB in the very high energy band above 30 GeV follows the stacked spectrum of BL Lac objects. Large Area Telescope data reveal the positive (1 + z) {sup k}, 1 < k < 4 cosmological evolution of the BL Lac source population consistent with that of their parent population, Fanaroff-Riley type I radio galaxies. We show that EGB at E > 30 GeV could be completely explained by emission from unresolved BL Lac objects if k {approx_equal} 3.

Neronov, A. [ISDC Data Center for Astrophysics, Chemin d'Ecogia 16, CH-1290 Versoix (Switzerland); Semikoz, D. V. [APC, 10 rue Alice Domon et Leonie Duquet, F-75205 Paris Cedex 13 (France)

2012-09-20T23:59:59.000Z

168

1 Mathematical Background 1 1.1 Prerequisites . . . . . . . . . . . . . . . . . . . . . . . . . 1  

E-Print Network (OSTI)

Contents 1 Mathematical Background 1 1.1 Prerequisites . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2 Computability Theory . . . . . . . . . . . . . . . . . . . . 4 1.3 Topology . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1.4 Probability Theory . . . . . . . . . . . . . . . . . . . . . . 8 1.5 Exercises and Problems

Goodman, James R.

169

1 Introduction 1 1.1 Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1  

E-Print Network (OSTI)

Contents 1 Introduction 1 1.1 Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2 Our Goal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.3 ICSI's HMM/ANN Hybrid Speech Recognition System . . . . . . . . 2 1.4 What is Multi­band Processing

Mirghafori, N. Nikki

170

Inhomogeneous Background Error Modeling and Estimation over Antarctica  

Science Journals Connector (OSTI)

The structure of the analysis increments in a variational data assimilation scheme is strongly driven by the formulation of the background error covariance matrix, especially in data-sparse areas such as the Antarctic region. The gridpoint ...

Yann Michel; Thomas Auligné

2010-06-01T23:59:59.000Z

171

Lovelock black holes in a string cloud background  

E-Print Network (OSTI)

We present an exact static, spherically symmetric black hole solution to the third order Lovelock gravity with a string cloud background in seven dimensions for the special case when the second and third order Lovelock coefficients are related via $\\tilde{\\alpha}^2_2=3\\tilde{\\alpha}_3\\;(\\equiv\\alpha^2)$. Further, we examine thermodynamic properties of this black hole to obtain exact expressions for mass, temperature, entropy and also perform the thermodynamic stability analysis. We see that a string cloud background makes a profound influence on horizon structure, thermodynamic properties and the stability of black holes. Interestingly, the entropy of the black hole is unaffected due to a string cloud background. However, the critical solution for thermodynamic stability is being affected by a string cloud background.

Tae-Hun Lee; Dharmanand Baboolal; Sushant G. Ghosh

2014-09-12T23:59:59.000Z

172

QCD background for the UA1 W?tb¯ signal  

Science Journals Connector (OSTI)

The cc¯X and bb¯X background affecting the W?tb¯ e/?+2 jets signal reported by the UA1 Collaboration is discussed. Calculations are based on an O(?s 2)+leading-pole approximation scheme, which includes jet radiation in the initial and final states of the hard binary parton process, and include the heavy-flavor excitation contribution, the stability of which has been checked. The main conclusions are the following. (i) Selection cuts naturally induce a topological event structure on the surviving background mimicking that expected for a W?tb¯ signal. (ii) The background rates for ?+2 jets events, on which we concentrate, are compatible within theoretical uncertainties with the number of events experimentally observed. The importance of purely leptonic decay modes, which survive the lepton-isolation cuts, and the bias induced by lepton-isolation cuts on background event topologies are also clarified.

A. Grosso and R. Odorico

1985-12-01T23:59:59.000Z

173

GammaSense: Infrastructureless Positioning Using Background Radioactivity  

Science Journals Connector (OSTI)

We introduce the harvesting of natural background radioactivity for positioning. Using a standard Geiger-Müller counter as sensor, we fingerprint the natural levels of gamma radiation with the aim of then roughly pinpointing the position of a client ...

Doina Bucur; Mikkel Baun Kjærgaard

2008-10-01T23:59:59.000Z

174

Simulation of PEP-II Accelerator Backgrounds Using TURTLE  

SciTech Connect

We present studies of accelerator-induced backgrounds in the BaBar detector at the SLAC B-Factory, carried out using LPTURTLE, a modified version of the DECAY TURTLE simulation package. Lost-particle backgrounds in PEP-II are dominated by a combination of beam-gas bremstrahlung, beam-gas Coulomb scattering, radiative-Bhabha events and beam-beam blow-up. The radiation damage and detector occupancy caused by the associated electromagnetic shower debris can limit the usable luminosity. In order to understand and mitigate such backgrounds, we have performed a full program of beam-gas and luminosity-background simulations, that include the effects of the detector solenoidal field, detailed modeling of limiting apertures in both collider rings, and optimization of the betatron collimation scheme in the presence of large transverse tails.

Barlow, R.J.; Fieguth, T.; /SLAC; Kozanecki, W.; /DSM, DAPNIA, Saclay; Majewski, S.A.; /Stanford U., Phys. Dept.; Roudeau, P.; Stocchi, A.; /Orsay, LAL

2006-02-15T23:59:59.000Z

175

The Cosmic Near Infrared Background: Remnant Light from Early Stars  

E-Print Network (OSTI)

The redshifted ultraviolet light from early stars at z ~ 10 contributes to the cosmic near infrared background. We present detailed calculations of its spectrum with various assumptions about metallicity and mass spectrum of early stars. We show that if the near infrared background has a stellar origin, metal-free stars are not the only explanation of the excess near infrared background; stars with metals (e.g. Z=1/50 Z_sun) can produce the same amount of background intensity as the metal-free stars. We quantitatively show that the predicted average intensity at 1-2 microns is essentially determined by the efficiency of nuclear burning in stars, which is not very sensitive to metallicity. We predict \

Elizabeth Fernandez; Eiichiro Komatsu

2005-08-08T23:59:59.000Z

176

Muon-Induced Backgrounds in Double Chooz Emily Conover  

E-Print Network (OSTI)

to scintillator 8 MeV n capture energy, 30µs backgrounds due to muons remain E¯e = Ee+ + 10-40keV En + 1.8MeMuon-Induced Backgrounds in Double Chooz Emily Conover University of Chicago Second Thesis and Stopped Muons 9Li and 8He 3. Double Chooz Results 4. Conclusions Timeline/Future work Emily Conover (Univ

177

The X-ray background and the evolution of AGN  

E-Print Network (OSTI)

We discuss the constraints on the AGN evolution from the cosmic X-ray background and source counts. A synthesis model to fit the X-ray background is presented. In the model, the spectrum of type 2 AGN has been modeled including Compton down--scattering within the absorbing material. Besides, we introduced a dependence on redshift of the relative number of obscured sources and found a decrease of the fraction of type 2 AGN at redshifts larger than 2.

Fulvio Pompilio; Fabio La Franca; Giorgio Matt

1999-09-23T23:59:59.000Z

178

Muon-induced backgrounds in the CUORICINO experiment  

E-Print Network (OSTI)

To better understand the contribution of cosmic ray muons to the CUORICINO background, 10 plastic scintillator detectors were installed at the CUORICINO site and operated during the final 3 months of the experiment. From these measurements, an upper limit of 0.0021 counts/(keV kg yr) (95% CL) was obtained on the cosmic ray-induced background in the neutrinoless double beta decay region of interest. The measurements were also compared to Geant4 simulations.

E. Andreotti; C. Arnaboldi; F. T. Avignone III; M. Balata; I. Bandac; M. Barucci; J. W. Beeman; F. Bellini; T. Bloxham; C. Brofferio; A. Bryant; C. Bucci; L. Canonica; S. Capelli; L. Carbone; M. Carrettoni; M. Clemenza; O. Cremonesi; R. J. Creswick; S. Di Domizio; M. J. Dolinski; L. Ejzak; R. Faccini; H. A. Farach; E. Ferri; F. Ferroni; E. Fiorini; L. Foggetta; A. Giachero; L. Gironi; A. Giuliani; P. Gorla; E. Guardincerri; T. D. Gutierrez; E. E. Haller; R. Kadel; K. Kazkaz; S. Kraft; L. Kogler; Yu. G. Kolomensky; C. Maiano; R. H. Maruyama; C. Martinez; M. Martinez; L. Mizouni; S. Morganti; S. Nisi; C. Nones; E. B. Norman; A. Nucciotti; F. Orio; M. Pallavicini; V. Palmieri; L. Pattavina; M. Pavan; M. Pedretti; G. Pessina; S. Pirro; E. Previtali; L. Risegari; C. Rosenfeld; C. Rusconi; C. Salvioni; S. Sangiorgio; D. Schaeffer; N. D. Scielzo; M. Sisti; A. R. Smith; C. Tomei; G. Ventura; M. Vignati

2009-12-18T23:59:59.000Z

179

Kinematic interpretation of string instability in a background gravitational field  

Science Journals Connector (OSTI)

The unstable regime in which the string oscillating modes develop imaginary frequencies is shown to be characterized, kinematically, by a positive relative acceleration among the different points of the string. Instability occurs when this acceleration, induced by the background curvature, is large enough to make the extension of the corresponding causally connected region smaller than the string maximal size. This kinematic characterization is applied, in particular, to discuss string instability in a static and spherically symmetric gravitational background.

M. Gasperini

1991-01-01T23:59:59.000Z

180

Background reduction and sensitivity for germanium double beta decay experiments  

E-Print Network (OSTI)

Germanium detectors have very good capabilities for the investigation of rare phenomena like the neutrinoless double beta decay. Rejection of the background entangling the expected signal is one primary goal in this kind of experiments. Here, the attainable background reduction in the energy region where the neutrinoless double beta decay signal of 76Ge is expected to appear has been evaluated for experiments using germanium detectors, taking into consideration different strategies like the granularity of the detector system, the segmentation of each individual germanium detector and the application of Pulse Shape Analysis techniques to discriminate signal from background events. Detection efficiency to the signal is affected by background rejection techniques, and therefore it has been estimated for each of the background rejection scenarios considered. Finally, conditions regarding crystal mass, radiopurity, exposure to cosmic rays, shielding and rejection capabilities are discussed with the aim to achieve a background level of 10-3 c keV-1 kg-1 y-1 in the region of interest, which would allow to explore neutrino effective masses around 40 meV.

H. Gómez; S. Cebrián; J. Morales; J. A. Villar

2007-08-29T23:59:59.000Z

Note: This page contains sample records for the topic "foreground background beaver" from the National Library of EnergyBeta (NLEBeta).
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181

Background-independent measurement of $?_{13}$ in Double Chooz  

E-Print Network (OSTI)

The oscillation results published by the Double Chooz collaboration in 2011 and 2012 rely on background models substantiated by reactor-on data. In this analysis, we present a background-model-independent measurement of the mixing angle $\\theta_{13}$ by including 7.53 days of reactor-off data. A global fit of the observed neutrino rates for different reactor power conditions is performed, yielding a measurement of both $\\theta_{13}$ and the total background rate. The results on the mixing angle are improved significantly by including the reactor-off data in the fit, as it provides a direct measurement of the total background rate. This reactor rate modulation analysis considers antineutrino candidates with neutron captures on both Gd and H, whose combination yields $\\sin^2(2\\theta_{13})=$ 0.102 $\\pm$ 0.028(stat.) $\\pm$ 0.033(syst.). The results presented in this study are fully consistent with the ones already published by Double Chooz, achieving a competitive precision. They provide, for the first time, a determination of $\\theta_{13}$ that does not depend on a background model.

Y. Abe; J. C. dos Anjos; J. C. Barriere; E. Baussan; I. Bekman; M. Bergevin; T. J. C. Bezerra; L. Bezrukov; E. Blucher; C. Buck; J. Busenitz; A. Cabrera; E. Caden; L. Camilleri; R. Carr; M. Cerrada; P. -J. Chang; E. Chauveau; P. Chimenti; A. P. Collin; E. Conover; J. M. Conrad; J. I. Crespo-Anadón; K. Crum; A. Cucoanes; E. Damon; J. V. Dawson; D. Dietrich; Z. Djurcic; M. Dracos; M. Elnimr; A. Etenko; M. Fallot; F. von Feilitzsch; J. Felde; S. M. Fernandes; V. Fischer; D. Franco; M. Franke; H. Furuta; I. Gil-Botella; L. Giot; M. Göger-Neff; L. F. G. Gonzalez; L. Goodenough; M. C. Goodman; C. Grant; N. Haag; T. Hara; J. Haser; M. Hofmann; G. A. Horton-Smith; A. Hourlier; M. Ishitsuka; J. Jochum; C. Jollet; F. Kaether; L. N. Kalousis; Y. Kamyshkov; D. M. Kaplan; T. Kawasaki; E. Kemp; H. de Kerret; T. Konno; D. Kryn; M. Kuze; T. Lachenmaier; C. E. Lane; T. Lasserre; A. Letourneau; D. Lhuillier; H. P. Lima Jr; M. Lindner; J. M. López-Castaño; J. M. LoSecco; B. K. Lubsandorzhiev; S. Lucht; J. Maeda; C. Mariani; J. Maricic; J. Martino; T. Matsubara; G. Mention; A. Meregaglia; T. Miletic; R. Milincic; A. Minotti; Y. Nagasaka; K. Nakajima; Y. Nikitenko; P. Novella; M. Obolensky; L. Oberauer; A. Onillon; A. Osborn; C. Palomares; I. M. Pepe; S. Perasso; P. Pfahler; A. Porta; G. Pronost; J. Reichenbacher; B. Reinhold; M. Röhling; R. Roncin; S. Roth; B. Rybolt; Y. Sakamoto; R. Santorelli; F. Sato; A. C. Schilithz; S. Schönert; S. Schoppmann; M. H. Shaevitz; R. Sharankova; S. Shimojima; V. Sibille; V. Sinev; M. Skorokhvatov; E. Smith; J. Spitz; A. Stahl; I. Stancu; L. F. F. Stokes; M. Strait; A. Stüken; F. Suekane; S. Sukhotin; T. Sumiyoshi; Y. Sun; R. Svoboda; K. Terao; A. Tonazzo; H. H. Trinh Thi; G. Valdiviesso; N. Vassilopoulos; C. Veyssiere; M. Vivier; S. Wagner; H. Watanabe; C. Wiebusch; L. Winslow; M. Wurm; G. Yang; F. Yermia; V. Zimmer

2014-04-25T23:59:59.000Z

182

Cavern background measurement with the ATLAS RPC system  

E-Print Network (OSTI)

The measurement of cavern background has been carried out systematically since the beginning of LHC, as soon as the luminosity produced a detectable signal, from L = 10^28 cm^2s^1 of the early 2010 operation up to L=10^28 cm^2s^1 at the end of 2011 proton-proton run, which is just 1/3 of the nominal LHC luminosity. The reason for this is to early foresee the running condition for the detector for the nominal LHC luminosity and beyond, in view of the super-LHC upgrade. Background Montecarlo calculations have been validated against data and the background map analysis pointed out hotspots due to localized cracks in the radiation shielding. The RPCs participated to this effort since the earliest stages providing an accurate correlation between luminosity and background, a 3D background map in the barrel region and a direct measurement of the cavern activation. Moreover due to the high sensitivity and very good signal to noise ratio of the proposed method, based on the gap current, the measurement was provided in...

Aielli, G; The ATLAS collaboration

2012-01-01T23:59:59.000Z

183

No increase in background, manmade radioactivity for Los Alamos area  

NLE Websites -- All DOE Office Websites (Extended Search)

March » March » Man-Made Radioactivity For Los Alamos area No increase in background, manmade radioactivity for Los Alamos area Two aerial flyovers found that radioisotopes and their associated exposure rates are consistent with those expected from normal background radiation. March 19, 2013 High southwest aerial view of Los Alamos National Laboratory (left) and Los Alamos townsite (middle and right). High southwest aerial view of Los Alamos National Laboratory (left) and Los Alamos townsite (middle and right). The results are good news and the information will benefit the Lab and the community for years to come as we work toward cleanup and sustainability. Two aerial flyovers of the Los Alamos area to determine the presence of background and manmade radioactivity found that radioisotopes and their

184

BACKGROUND REVIEW OF THE BRUSH BERYLLIUM AND DIAMOND MAGNESIUM PLANTS  

Office of Legacy Management (LM)

BACKGROUND REVIEW OF THE BRUSH BERYLLIUM AND DIAMOND MAGNESIUM PLANTS BACKGROUND REVIEW OF THE BRUSH BERYLLIUM AND DIAMOND MAGNESIUM PLANTS IN LUCKEY, OHIO October 27, 1989 Prepared for: U.S. Department of Energy Formerly Utilized Sites Remedial Action Program Prepared by: R.F. Weston/Office of Technical Services BACKGROUND REVIEW OF THE BRUSH BERYLLIUM AND DIAMOND MAGNESIUM PLANTS IN LUCKEY, OHIO INTRODUCTION The Department of Energy (DOE) is conducting a program to identify and examine the radiological conditions at sites used in the early years of nuclear energy development by the U.S. Army Corps of Engineer's Manhattan Engineer District (MED) and the Atomic Energy Commission (AEC). This program, the Formerly Utilized Sites Remedial Action Program (FUSRAP), is administered by the Assistant Secretary for Nuclear Energy through the

185

Direct Imaging of Exoplanets Without Background Subtraction: Implications for ELTs  

E-Print Network (OSTI)

The ultra-high contrast capability required to form images of other solar systems is arguably the highest-profile challenge in astronomy today. The current high-contrast imaging efforts all require background subtraction to separate the planetary image from the image of the host star. Background estimation is difficult due to the presence of non-common path aberrations (NCPAs) that change with time. The only major source of information that is not being utilized by current efforts is the random encoding of the planetary image and the NCPAs by the atmosphere on millisecond time-scales. Here, a method that utilizes this information in order to avoid background subtraction altogether is proposed. This new paradigm will allow simultaneous estimation of the time-dependent NCPAs and the planetary image via rigorous statistical inference procedures. These procedures are fully compatible with other information sources, such as diurnal field rotation and spectral diversity. Given the open-ended nature of the backgroun...

Frazin, Richard A

2015-01-01T23:59:59.000Z

186

Extended Mosaic Observations with the Cosmic Background Imager  

E-Print Network (OSTI)

Two years of microwave background observations with the Cosmic Background Imager (CBI) have been combined to give a sensitive, high resolution angular power spectrum over the range 400 2000 power previously seen with the CBI is reduced. Under the assumption that any signal in excess of the primary anisotropy is due to a secondary Sunyaev-Zeldovich anisotropy in distant galaxy clusters we use CBI, ACBAR, and BIMA data to place a constraint on the present-day rms mass fluctuation sigma_8. We present the results of a cosmological parameter analysis on the l < 2000 primary anisotropy data which show significant improvements in the parameters as compared to WMAP alone, and we explore the role of the small-scale cosmic microwave background data in breaking parameter degeneracies.

A. C. S. Readhead; B. S. Mason; C. R. Contaldi; T. J. Pearson; J. R. Bond; S. T. Myers; S. Padin; J. L. Sievers; J. K. Cartwright; M. C. Shepherd; D. Pogosyan; S. Prunet; P. Altamirano; R. Bustos; L. Bronfman; S. Casassus; W. L. Holzapfel; J. May; U. -L. Pen; S. Torres; P. S. Udomprasert

2004-02-15T23:59:59.000Z

187

The local potential approximation in the background field formalism  

E-Print Network (OSTI)

Working within the familiar local potential approximation, and concentrating on the example of a single scalar field in three dimensions, we show that the commonly used approximation method of identifying the total and background fields, leads to pathologies in the resulting fixed point structure and the associated spaces of eigenoperators. We then show how a consistent treatment of the background field through the corresponding modified shift Ward identity, can cure these pathologies, restoring universality of physical quantities with respect to the choice of dependence on the background field, even within the local potential approximation. Along the way we point out similarities to what has been previously found in the f(R) approximation in asymptotic safety for gravity.

I. Hamzaan Bridle; Juergen A. Dietz; Tim R. Morris

2014-03-20T23:59:59.000Z

188

Reducing backgrounds in the higgs factory muon collider detector  

SciTech Connect

A preliminary design of the 125-GeV Higgs Factory (HF) Muon Collider (MC) has identified an enormous background loads on the HF detector. This is related to the twelve times higher muon decay probability at HF compared to that previously studied for the 1.5-TeV MC. As a result of MARS15 optimization studies, it is shown that with a carefully designed protection system in the interaction region, in the machine-detector interface and inside the detector one can reduce the background rates to a manageable level similar to that achieved for the optimized 1.5-TeV case. The main characteristics of the HF detector background are presented for the configuration found.

Mokhov, N. V.; Tropin, I. S.

2014-06-01T23:59:59.000Z

189

Background: Today's Solyndra Solar Hearing | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Background: Today's Solyndra Solar Hearing Background: Today's Solyndra Solar Hearing Background: Today's Solyndra Solar Hearing September 14, 2011 - 12:04am Addthis Dan Leistikow Dan Leistikow Former Director, Office of Public Affairs This morning, the House Energy and Commerce Subcommittee on Oversight and Investigations is holding a hearing to discuss Solyndra Solar, the California-based solar manufacturer that declared bankruptcy last week. Jonathan Silver, Executive Director of the Department's Loan Programs Office, will be testifying. We've posted Jonathan's written testimony online. The testimony is very thorough and provides a good explanation of the loan process and the extensive reviews and analysis conducted by the Department between 2006 and 2009. He also explains the remarkable changes in the solar market since

190

Gravitational-Wave Stochastic Background from Cosmic Strings  

Science Journals Connector (OSTI)

We consider the stochastic background of gravitational waves produced by a network of cosmic strings and assess their accessibility to current and planned gravitational wave detectors, as well as to big bang nucleosynthesis (BBN), cosmic microwave background (CMB), and pulsar timing constraints. We find that current data from interferometric gravitational wave detectors, such as Laser Interferometer Gravitational Wave Observatory (LIGO), are sensitive to areas of parameter space of cosmic string models complementary to those accessible to pulsar, BBN, and CMB bounds. Future more sensitive LIGO runs and interferometers such as Advanced LIGO and Laser Interferometer Space Antenna (LISA) will be able to explore substantial parts of the parameter space.

Xavier Siemens; Vuk Mandic; Jolien Creighton

2007-03-13T23:59:59.000Z

191

Radiative emission of neutrino pair free of quantum electrodynamic backgrounds  

E-Print Network (OSTI)

A scheme of quantum electrodynamic (QED) background-free radiative emission of neutrino pair (RENP) is proposed in order to achieve precision determination of neutrino properties so far not accessible. The important point for the background rejection is the fact that the dispersion relation between wave vector along propagating direction in wave guide (and in a photonic-crystal type fiber) and frequency is modified by a discretized non-vanishing effective mass. This effective mass acts as a cutoff of allowed frequencies, and one may select the RENP photon energy region free of all macro-coherently amplified QED processes by choosing the cutoff larger than the mass of neutrinos.

Yoshimura, M; Tanaka, M

2015-01-01T23:59:59.000Z

192

Connection between the pinch technique and the background field method  

Science Journals Connector (OSTI)

The connection between the pinch technique and the background field method is further explored. We show by explicit calculations that the application of the pinch technique in the framework of the background field method gives rise to exactly the same results as in the linear renormalizable gauges. The general method for extending the pinch technique to the case of Green’s functions with off-shell fermions as incoming particles is presented. As an example, the one-loop gauge-independent quark self-energy is constructed. We briefly discuss the possibility that the gluonic Green’s functions, obtained by either method, correspond to physical quantities.

Joannis Papavassiliou

1995-01-15T23:59:59.000Z

193

Radiative emission of neutrino pair free of quantum electrodynamic backgrounds  

E-Print Network (OSTI)

A scheme of quantum electrodynamic (QED) background-free radiative emission of neutrino pair (RENP) is proposed in order to achieve precision determination of neutrino properties so far not accessible. The important point for the background rejection is the fact that the dispersion relation between wave vector along propagating direction in wave guide (and in a photonic-crystal type fiber) and frequency is modified by a discretized non-vanishing effective mass. This effective mass acts as a cutoff of allowed frequencies, and one may select the RENP photon energy region free of all macro-coherently amplified QED processes by choosing the cutoff larger than the mass of neutrinos.

M. Yoshimura; N. Sasao; M. Tanaka

2015-01-23T23:59:59.000Z

194

Beam-Induced Backgrounds in the CLIC Detectors  

E-Print Network (OSTI)

The beam parameters of the proposed CLIC linear electron-positron collider with a centre-of-mass energy of up to 3 TeV will lead to high rates of beam-induced background events. In this note simulation studies of ?? ? hadron interactions and of incoherent electron-positron pair production are presented. The CLIC detector concepts and their optimisation to reduce background occupancies are described. The characteristics of the events are discussed and resulting occupancies and energy deposits, as well as expected levels of both total ionising dose and displacement damage in the detectors are discussed.

Dannheim, D

2012-01-01T23:59:59.000Z

195

The Cosmic Microwave Background: Beyond the Power Spectrum  

E-Print Network (OSTI)

Much recent work on the cosmic microwave background (CMB) has focussed on the angular power spectrum of temperature anisotropies and particularly on the recovery of cosmological parameters from acoustic peaks in the power spectrum. However, there is more that can conceivably be done with CMB measurements. Here I briefly survey a few such ideas: cross-correlation with other cosmic backgrounds as a probe of the density of the Universe; CMB polarization as a gravitational-wave detector; secondary anisotropies and the ionization history of the Universe; tests of alternative-gravity theories; polarization, the Sunyaev-Zeldovich effect, and cosmic variance; and tests for a neutrino mass.

Marc Kamionkowski

1998-09-24T23:59:59.000Z

196

Background Fact Sheet Transfer of Depleted Uranium and Subsequent Transactions  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Background Fact Sheet Background Fact Sheet Transfer of Depleted Uranium and Subsequent Transactions At the direction of Energy Secretary Steven Chu, over many months, the Energy Department (DOE) has been working closely with Energy Northwest (ENW), the Tennessee Valley Authority (TVA), and USEC Inc. (USEC) to develop a plan to address the challenges at USEC's Paducah Gaseous Diffusion Plant (GDP) that advances America's national security interests, protects taxpayers, and provides benefits for TVA and the Bonneville Power Administration's (BPA's) electric ratepayers and business operations. BPA is ENW's sole customer, purchasing 100 percent of ENW's Columbia Generating Station's electric power as part of BPA's overall

197

The Anisotropy of the Microwave Background to l = 3500: Deep Field Observations with the Cosmic Background Imager  

E-Print Network (OSTI)

We report measurements of anisotropy in the cosmic microwave background radiation over the multipole range l ~ 200 - 3500 with the Cosmic Background Imager based on deep observations of three fields. These results confirm the drop in power with increasing l first reported in earlier measurements with this instrument, and extend the observations of this decline in power out to l \\~ 2000. The decline in power is consistent with the predicted damping of primary anisotropies. At larger multipoles, l = 2000 - 3500, the power is 3.1 sigma greater than standard models for intrinsic microwave background anisotropy in this multipole range, and 3.5 sigma greater than zero. This excess power is not consistent with expected levels of residual radio source contamination but, for sigma_8 >~ 1, is consistent with predicted levels due to a secondary Sunyaev-Zeldovich anisotropy. Further observations are necessary to confirm the level of this excess and, if confirmed, determine its origin.

B. S. Mason; T. J. Pearson; A. C. S. Readhead; M. C. Shepherd; J. L. Sievers; P. S. Udomprasert; J. K. Cartwright; A. J. Farmer; S. Padin; S. T. Myers; J. R. Bond; C. R. Contaldi; U. -L. Pen; S. Prunet; D. Pogosyan; J. E. Carlstrom; J. Kovac; E. M. Leitch; C. Pryke; N. W. Halverson; W. L. Holzapfel; P. Altamirano; L. Bronfman; S. Casassus; J. May; M. Joy

2002-05-22T23:59:59.000Z

198

Origin of the High Energy Cosmic Neutrino Background  

Science Journals Connector (OSTI)

The diffuse background of very high energy extraterrestrial neutrinos recently discovered with IceCube is compatible with that expected from cosmic ray interactions in the Galactic interstellar medium plus that expected from hadronic interactions near the source and in the intergalactic medium of the cosmic rays which have been accelerated by the jets that produce gamma ray bursts.

Shlomo Dado and Arnon Dar

2014-11-07T23:59:59.000Z

199

Rev. January 30, 2012 1 REFERENCE and BACKGROUND CHECK  

E-Print Network (OSTI)

Rev. January 30, 2012 1 REFERENCE and BACKGROUND CHECK PROCESS HUMAN RESOURCES Workforce Planning, as allowed by law, and consistent with the job described. The appropriate Workforce Planning Analyst the documentation. (Please note that the review will take place in Human Resources, under a Workforce Planning

Eirinaki, Magdalini

200

Compressed Gas Cylinder Safety I. Background. Due to the nature  

E-Print Network (OSTI)

Compressed Gas Cylinder Safety I. Background. Due to the nature of gas cylinders hazards of a ruptured cylinder. There are almost 200 different types of materials in gas cylinders, there are several general procedures to follow for safe storage and handling of a compressed gas cylinder: II

Suzuki, Masatsugu

Note: This page contains sample records for the topic "foreground background beaver" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

3.5 Nanowire Sensors 3.5.1 Background  

E-Print Network (OSTI)

117 3.5 Nanowire Sensors 3.5.1 Background Nanowires are solid, rod-like materials with diameters that similar commercial products will eventually be available. 3.5.2 Description Nanowire sensors have et al. 2003). A comprehensive review of current research activities on chemical sensors based

202

STRING LOOPS IN BACKGROUND FIELDS Scott Alan Yost  

E-Print Network (OSTI)

excellent collaborators. They have made my stay at Princeton very productive and enjoyable. I thank E. LiebSTRING LOOPS IN BACKGROUND FIELDS Scott Alan Yost A dissertation presented to the faculty formalism. ii #12;Acknowledgements I would like to thank my advisor, Chiara Nappi, for her support, advice

Yost, Scott

203

1 Background 1.1 Topic of research  

E-Print Network (OSTI)

1 Background 1.1 Topic of research Mathematical quantitative tools (like probabil- ity theory analyses on the basis of these meth- ods. 1.2 Academic and industrial con- text Interference in a security section 1.3). Applications of this work can be found in large scale, mission critical, security related

Hunt, Sebastian

204

An array of low-background 3 He proportional counters  

E-Print Network (OSTI)

with a mixture of 3 He and CF4 gas capable of detecting the neutrons liberated by the neutrino-deuteron neutral current reaction in the D2O, and four strings filled with a mixture of 4 He and CF4 gas for background

Waltham, Chris

205

Observation of objects under intense plasma background illumination  

SciTech Connect

Experiments on the observation of a brightness-amplified image of an object through a masking arc discharge are presented. The copper-vapor laser active medium was used as an image brightness amplifier. It is shown that the image quality does not worsen under plasma background illumination.

Buzhinsky, R. O.; Savransky, V. V. [Russian Academy of Sciences, Natural Science Center, Prokhorov Institute of General Physics (Russian Federation); Zemskov, K. I.; Isaev, A. A. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation); Buzhinsky, O. I. [Troitsk Institute for Innovation and Fusion Research (Russian Federation)

2010-12-15T23:59:59.000Z

206

II. HISTORICAL BACKGROUND Since 1977 the University of Oregon Solar  

E-Print Network (OSTI)

of utilities headed by the Eugene Water and Electric Board initiated the Re- gional Solar Radiation Monitoring2 II. HISTORICAL BACKGROUND Since 1977 the University of Oregon Solar Monitoring Laboratory has operated a solar radiation monitoring network in the Pacific Northwest. The number of stations participat

Oregon, University of

207

MARSAME Appendix B B. SOURCES OF BACKGROUND RADIOACTIVITY  

E-Print Network (OSTI)

consideration is given to issues associated with technologically enhanced naturally occurring radioactive reports on Exposure of the Population in the United States and Canada from Natural Background Radiation.1 Terrestrial Radioactivity The naturally occurring forms of radioactive elements incorporated into the Earth

208

Seeing is Believing: It's All About the Background  

E-Print Network (OSTI)

Seeing is Believing: It's All About the Background Thomas Meade Eileen Foell Chair in Cancer may promise for the experimental and clinical settings. Speaker Bio Thomas Meade, Ph.D., Received BS of Technology in the laboratory of Professor Harry B. Gray. In 1991 he joined the Division of Biology

Zanibbi, Richard

209

Cosmic and Galactic Neutrino Backgrounds from Thermonuclear Sources  

E-Print Network (OSTI)

We estimate energy spectra and fluxes at the Earth's surface of the cosmic and Galactic neutrino backgrounds produced by thermonuclear reactions in stars. The extra-galactic component is obtained by combining the most recent estimates of the cosmic star formation history and the stellar initial mass function with accurate theoretical predictions of the neutrino yields all over the thermonuclear lifetime of stars of different masses. Models of the structure and evolution of the Milky Way are used to derive maps of the expected flux generated by Galactic sources as a function of sky direction. The predicted neutrino backgrounds depend only slightly on model parameters. In the relevant 50 keV-10 MeV window, the total flux of cosmic neutrinos ranges between 20 and 65 particles per square cm per s. Neutrinos reaching the Earth today have been typically emitted at redshift z~2. Their energy spectrum peaks at E~0.1-0.3 MeV. The energy and entropy densities of the cosmic background are negligible with respect to the thermal contribution of relic neutrinos originated in the early universe. In every sky direction, the cosmic background is outnumbered by the Galactic one, whose integrated flux amounts to 300-1000 particles per square cm per s. The emission from stars in the Galactic disk contributes more than 95 per cent of the signal.

Cristiano Porciani; Silvia Petroni; Giovanni Fiorentini

2003-11-20T23:59:59.000Z

210

Is natural background or radiation from nuclear power plants leukemogenic  

SciTech Connect

The objective in this review is to provide some facts about normal hemopoietic cell proliferation relevant to leukemogenesis, physical, chemical, and biological facts about radiation effects with the hope that each person will be able to decide for themselves whether background radiation or emissions from nuclear power plants and facilities significantly add to the spontaneous leukemia incidence. 23 refs., 1 tab.

Cronkite, E.P.

1989-01-01T23:59:59.000Z

211

The prospects for polarized target materials with pure carbon background  

SciTech Connect

None of the materials presently in common use for polarized proton targets has a pure carbon nuclear background. The alcohols and diols contain some oxygen, and the ammonia and amine-based materials contain nitrogen and/or other noncarbon species. In the latter cases the noncarbon nuclei are measurably polarized as a concomitant of the process used to polarize the hydrogen nuclei. The relative simplicity of a pure carbon background would be advantageous for most types of scattering experiments and perhaps crucial for some. In addition to simplifying the kinematics of background events, pure carbon is relatively easy to prepare as a ``dummy`` target for background subtraction. Also, in such a target material, {sup 13}C-enrichment would yield a clean polarized {sup 13}C material. In this note I explore the possibilities for such materials, touching upon only what I consider to be the ``high`` points. The subject matter is capable of nearly endless ramification and speculation. In fact, owing to a general lack of relevant experimental data, even this relatively brief note contains much that is speculative to some degree.

Hill, D.A.

1992-10-06T23:59:59.000Z

212

The prospects for polarized target materials with pure carbon background  

SciTech Connect

None of the materials presently in common use for polarized proton targets has a pure carbon nuclear background. The alcohols and diols contain some oxygen, and the ammonia and amine-based materials contain nitrogen and/or other noncarbon species. In the latter cases the noncarbon nuclei are measurably polarized as a concomitant of the process used to polarize the hydrogen nuclei. The relative simplicity of a pure carbon background would be advantageous for most types of scattering experiments and perhaps crucial for some. In addition to simplifying the kinematics of background events, pure carbon is relatively easy to prepare as a dummy'' target for background subtraction. Also, in such a target material, [sup 13]C-enrichment would yield a clean polarized [sup 13]C material. In this note I explore the possibilities for such materials, touching upon only what I consider to be the high'' points. The subject matter is capable of nearly endless ramification and speculation. In fact, owing to a general lack of relevant experimental data, even this relatively brief note contains much that is speculative to some degree.

Hill, D.A.

1992-10-06T23:59:59.000Z

213

Overcoming a critical background to Higgs-boson detection  

Science Journals Connector (OSTI)

We show that it may well be possible to overcome the jjW background to Higgs-boson detection in mixed hadronic-leptonic final decay channels, while maintaining substantial event rates, even for Higgs-boson masses as high as 1 TeV.

J. F. Gunion and M. Soldate

1986-08-01T23:59:59.000Z

214

A method for enhancement of background sounds in forensic  

E-Print Network (OSTI)

A method for enhancement of background sounds in forensic audio recordings Robert C. Maher;Outline · Introduction ­ Audio forensic analysis ­ Adaptive interference cancelling ­ Sinusoidal modeling · Test implementation · Example processing · Conclusion #12;Audio Forensics · Audio Forensics

Maher, Robert C.

215

Differential Microwave Radiometer and the Cosmic Microwave Background |  

Office of Science (SC) Website

Differential Differential Microwave Radiometer and the Cosmic Microwave Background Laboratory Policy and Evaluation (LPE) LPE Home Staff M&O Contracts SC Laboratory Appraisal Process Laboratory Planning Process Work for Others in the Office of Science Laboratory Directed Research and Development (LDRD) DOE's Philosophy on LDRD Frequently Asked Questions Success Stories Brochures Additional Information LDRD Program Contacts Technology Transfer DOE National Laboratories Contact Information Laboratory Policy and Evaluation U.S. Department of Energy SC-32/Forrestal Building 1000 Independence Ave., SW Washington, DC 20585 P: (202) 586-5447 F: (202) 586-3119 Success Stories Differential Microwave Radiometer and the Cosmic Microwave Background Print Text Size: A A A RSS Feeds FeedbackShare Page

216

Home Energy Score Research and Background | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Residential Buildings » Home Energy Score » Home Energy Score Residential Buildings » Home Energy Score » Home Energy Score Research and Background Home Energy Score Research and Background Scoring Tool v.2014 In January 2014, the U.S. Department of Energy (DOE) released the first major update to the Home Energy Scoring Tool. After more than a year of implementation and feedback from program Partners, DOE made significant improvements to the scoring tool's calculation methodology and user interface. A newly refined scoring system will allow inefficient homes to more easily move up the scale with investments in efficiency improvements. This enhanced mobility is expected to help motivate greater action among homeowners. The Energy Department's National Renewable Energy Laboratory (NREL) performed a variety of analyses to test the updated scoring tool. Analysis

217

Plane-parallel waves as duals of the flat background  

E-Print Network (OSTI)

We give a classification of non-Abelian T-duals of the flat metric in D=4 dimensions with respect to the four-dimensional continuous subgroups of the Poincare group. After dualizing the flat background, we identify majority of dual models as conformal sigma models in plane-parallel wave backgrounds, most of them having torsion. We give their form in Brinkmann coordinates. We find, besides the plane-parallel waves, several diagonalizable curved metrics with nontrivial scalar curvature and torsion. Using the non-Abelian T-duality, we find general solution of the classical field equations for all the sigma models in terms of d'Alembert solutions of the wave equation.

Ladislav Hlavaty; Ivo Petr

2014-12-03T23:59:59.000Z

218

Performance Oversight Group: Background and Guidelines for Presenters  

NLE Websites -- All DOE Office Websites (Extended Search)

Oversight Group: Oversight Group: Background and Guidelines for Presenters Carl Strawbridge Office of Integrated Planning and Performance Management (formerly OPPS) Dean Hoffer Office of Project Support Services (formerly OPMO) 1 11/29/2012 Overview * Why POG? * Background on Laboratory Changes to Project Management Processes * POG Charter - Purpose - Membership - Roles & Responsibilities - Procedures * POG pilot meeting agenda, December 10 * Discussion--Guidelines for Presenters * Questions/Clarifications/Suggestions 2 11/29/2012 Why POG * Fermilab is managing a large number of major scientific capital construction projects to meet the future science agenda for the lab - May be unique in this respect within the DOE complex * Existing project support and oversight mechanisms not suitable for

219

Type I background fields in terms of type IIB ones  

E-Print Network (OSTI)

We choose such boundary conditions for open IIB superstring theory which preserve N=1 SUSY. The explicite solution of the boundary conditions yields effective theory which is symmetric under world-sheet parity transformation $\\Omega:\\sigma\\to-\\sigma$. We recognize effective theory as closed type I superstring theory. Its background fields,beside known $\\Omega$ even fields of the initial IIB theory, contain improvements quadratic in $\\Omega$ odd ones.

B. Nikolic; B. Sazdovic

2008-04-16T23:59:59.000Z

220

RESOLVING THE RADIO SOURCE BACKGROUND: DEEPER UNDERSTANDING THROUGH CONFUSION  

SciTech Connect

We used the Karl G. Jansky Very Large Array to image one primary beam area at 3 GHz with 8'' FWHM resolution and 1.0 {mu}Jy beam{sup -1} rms noise near the pointing center. The P(D) distribution from the central 10 arcmin of this confusion-limited image constrains the count of discrete sources in the 1 < S({mu}Jy) < 10 range. At this level, the brightness-weighted differential count S {sup 2} n(S) is converging rapidly, as predicted by evolutionary models in which the faintest radio sources are star-forming galaxies; and Almost-Equal-To 96% of the background originating in galaxies has been resolved into discrete sources. About 63% of the radio background is produced by active galactic nuclei (AGNs), and the remaining 37% comes from star-forming galaxies that obey the far-infrared (FIR)/radio correlation and account for most of the FIR background at {lambda} Almost-Equal-To 160 {mu}m. Our new data confirm that radio sources powered by AGNs and star formation evolve at about the same rate, a result consistent with AGN feedback and the rough correlation of black hole and stellar masses. The confusion at centimeter wavelengths is low enough that neither the planned Square Kilometre Array nor its pathfinder ASKAP EMU survey should be confusion limited, and the ultimate source detection limit imposed by 'natural' confusion is {<=}0.01 {mu}Jy at {nu} = 1.4 GHz. If discrete sources dominate the bright extragalactic background reported by ARCADE 2 at 3.3 GHz, they cannot be located in or near galaxies and most are {<=}0.03 {mu}Jy at 1.4 GHz.

Condon, J. J.; Cotton, W. D.; Fomalont, E. B.; Kellermann, K. I. [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903 (United States); Miller, N. [Department of Astronomy, University of Maryland, College Park, MD 20742-2421 (United States); Perley, R. A. [National Radio Astronomy Observatory, P.O. Box 0, Socorro, NM 87801 (United States); Scott, D.; Vernstrom, T.; Wall, J. V. [Department of Physics and Astronomy, University of British Columbia, Vancouver, BC V6T 1C1 (Canada)

2012-10-10T23:59:59.000Z

Note: This page contains sample records for the topic "foreground background beaver" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Towards a compensatable Muon Collider calorimeter with manageable backgrounds  

SciTech Connect

Muon Collider detectors pose very challenging problems in detector technology due to extremely large backgrounds present in the detector volume as a result of muon decays. Current designs of a 750 GeV/c per beam Muon Collider envisage 4.28 x 10{sup 5} muon decays per meter in the beam pipe close to the interaction region. The decay electrons after intense shielding still manage to produce large backgrounds in the detector volume of low energy photons, neutrons and higher energy Bethe Heitler muons. There are 170/184/6.8/177 TeVs energy entering the detector volume per crossing due to EM particles/Muons/Mesons/Baryons respectively. We investigate the capabilities of an iron calorimeter with pixelated readout where each pixel gives a yes/no answer as to whether a charged particle passed through it or not, to solve this problem. Each pixel is individually triggered by a 'travelling gate trigger' with a gate of 2 ns where the beginning of the gate is the time of arrival of a light signal from the interaction region to the pixel. We show that such a calorimeter is compensatable and propose two schemes to compensate the digital output in software to improve the resolution of the calorimeter. We show that such a calorimeter is capable of digitizing physics signals from the interaction region and as a result, the backgrounds from the muon decays are much reduced and under control.

Raja, R.; /Fermilab

2012-04-01T23:59:59.000Z

222

Background Characterization for Thermal Ion Release Experiments with 224Ra  

SciTech Connect

The Enriched Xenon Observatory for neutrinoless double beta decay uses {sup 136}Ba identification as a means for verifying the decay's occurrence in {sup 136}Xe. A current challenge is the release of Ba ions from the Ba extraction probe, and one possible solution is to heat the probe to high temperatures to release the ions. The investigation of this method requires a characterization of the alpha decay background in our test apparatus, which uses a {sup 228}Th source that produces {sup 224}Ra daughters, the ionization energies of which are similar to those of Ba. For this purpose, we ran a background count with our apparatus maintained at a vacuum, and then three counts with the apparatus filled with Xe gas. We were able to match up our alpha spectrum in vacuum with the known decay scheme of {sup 228}Th, while the spectrum in xenon gas had too many unresolved ambiguities for an accurate characterization. We also found that the alpha decays occurred at a near-zero rate both in vacuum and in xenon gas, which indicates that the rate was determined by {sup 228}Th decays. With these background measurements, we can in the future make a more accurate measurement of the temperature dependency of the ratio of ions to neutral atoms released from the hot surface of the probe, which may lead to a successful method of Ba ion release.

Kwong, H.; /Stanford U., Phys. Dept.; Rowson, P.; /SLAC

2005-12-15T23:59:59.000Z

223

Ultrarelativistic electron states in a general background electromagnetic field  

E-Print Network (OSTI)

The feasibility of obtaining exact analytical results in the realm of QED in the presence of a background electromagnetic field is almost exclusively limited to a few tractable cases, where the Dirac equation in the corresponding background field can be solved analytically. This circumstance has restricted, in particular, the theoretical analysis of QED processes in intense laser fields to within the plane-wave approximation even at those high intensities, achievable experimentally only by tightly focusing the laser energy in space. Here, within the Wentzel-Kramers-Brillouin (WKB) or eikonal approximation, we construct analytically single-particle electron states in the presence of a background electromagnetic field of general space-time structure in the realistic assumption that the initial energy of the electron is the largest dynamical energy scale in the problem. The relatively compact expression of these states opens, in particular, the possibility of investigating analytically strong-field QED processes in the presence of spatially focused laser beams, which is of particular relevance in view of the upcoming experimental campaigns in this field.

A. Di Piazza

2014-07-27T23:59:59.000Z

224

Beaver County, Oklahoma: Energy Resources | Open Energy Information  

Open Energy Info (EERE)

186°, -100.5296115° 186°, -100.5296115° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":36.7440186,"lon":-100.5296115,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

225

Beaver Cove, Maine: Energy Resources | Open Energy Information  

Open Energy Info (EERE)

60582°, -69.4606148° 60582°, -69.4606148° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":45.560582,"lon":-69.4606148,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

226

Beaver County, Pennsylvania: Energy Resources | Open Energy Information  

Open Energy Info (EERE)

812°, -80.365865° 812°, -80.365865° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":40.6367812,"lon":-80.365865,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

227

Beaver County, Utah: Energy Resources | Open Energy Information  

Open Energy Info (EERE)

266376°, -113.287085° 266376°, -113.287085° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":38.3266376,"lon":-113.287085,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

228

Directions to the Social Security Office 135 Beaver Street, Waltham  

E-Print Network (OSTI)

://www.brandeis.edu/publicsafety/safety/escort/schedule.html) 2. Take Bus 554 towards Waverly via Newton Corner & Mass. Pike (see schedule and fares at www.mbta

Fraden, Seth

229

Beaver Creek, Minnesota: Energy Resources | Open Energy Information  

Open Energy Info (EERE)

Minnesota: Energy Resources Minnesota: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 43.6141384°, -96.3644807° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":43.6141384,"lon":-96.3644807,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

230

Problem Set 6 Assigned, Wednesday, March 26, 2014  

E-Print Network (OSTI)

: #12; 05.Foreground|10)A(IPr , 2.Foreground|30)A(IPr , 3.Foreground|40)A(IPr . and 3.Background|10)A(IPr , 1.Background|30)A(IPr , 05.Background|40)A(IPr . Draw a graph that the graph cut

Jacobs, David

231

Background Measurements from Balloon-Borne CZT Detectors  

E-Print Network (OSTI)

We report detector characteristics and background measurements from two prototype imaging CZT detectors flown on a scientific balloon payload in May 2001. The detectors are both platinum-contact 10mm x 10mm x 5mm CZT crystals, each with a 4 $\\times$ 4 array of pixels tiling the anode. One is made from IMARAD horizontal Bridgman CZT, the other from eV Products high-pressure Bridgman material. Both detectors were mounted side-by-side in a flip-chip configuration and read out by a 32-channel IDE VA/TA ASIC preamp/shaper. We enclosed the detectors in the same 40deg field-of-view collimator (comprisinga graded passive shield and plastic scintillator) used in our previously-reported September 2000 flight. I-V curves for the detectors are diode-like, and we find that the platinum contacts adhere significantly better to the CZT surfaces than gold to previous detectors. The detectors and instrumentation performed well in a 20-hour balloon flight on 23/24 May 2001. Although we discovered a significant instrumental background component in flight, it was possible to measure and subtract this component from the spectra. The resulting IMARAD detector background spectrum (from 30 keV to ~450 keV) reaches ~5 x 10^{-3}$ counts/cm^2 -sec-keV at 100 keV and has a power-law index of ~2 at high energies. The eV Products detector has a similar spectrum, although there is more uncertainty in the energy scale because of calibration complications.

Johnathan A Jenkins; Tomohiko Narita; Jonathan E. Grindlay; Peter F. Bloser; Carl Stahle; Brad Parker; Scott Barthelmy

2002-11-25T23:59:59.000Z

232

FY 2013 FRPC DATA REPORTING INSTRUCTIONS I. Background  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

FY 2013 FRPC DATA REPORTING INSTRUCTIONS I. Background Executive Order 13327, "Federal Real Property Asset Management" was created to promote the efficient and economical use of the Federal Government's real property assets. The E.O. established the interagency Federal Real Property Council (FRPC), established the role of the Senior Real Property Officer, and mandated the creation of a centralized real property database. This document provides instructions for populating the required data in FIMS so that the Department can report in accordance with the FY 2013 FRPC reporting requirements.

233

A New Measurement of the Cosmic X-ray Background  

SciTech Connect

I present a new analytical description of the cosmic X-ray background (CXRB) spectrum in the 1.5-200 keV energy band, obtained by combining the new measurement performed by the Swift X-ray telescope (XRT) with the recently published Swift burst alert telescope (BAT) measurement. A study of the cosmic variance in the XRT band (1.5-7 keV) is also presented. I find that the expected cosmic variance (expected from LogN-LogS) scales as {omega}{sup -0.3}(where {omega} is the surveyed area) in very good agreement with XRT data.

Moretti, A. [INAF-Osservatorio Astronomico di Brera v. E. Bianchi 46 23807 Merate (Italy)

2009-05-11T23:59:59.000Z

234

Translational invariance and the anisotropy of the cosmic microwave background  

SciTech Connect

Primordial quantum fluctuations produced by inflation are conventionally assumed to be statistically homogeneous, a consequence of translational invariance. In this paper we quantify the potentially observable effects of a small violation of translational invariance during inflation, as characterized by the presence of a preferred point, line, or plane. We explore the imprint such a violation would leave on the cosmic microwave background anisotropy, and provide explicit formulas for the expected amplitudes of the spherical-harmonic coefficients.

Carroll, Sean M.; Tseng, C.-Y.; Wise, Mark B. [California Institute of Technology, Pasadena, California 91125 (United States)

2010-04-15T23:59:59.000Z

235

Renormalization ambiguities and conformal anomaly in metric-scalar backgrounds  

SciTech Connect

We analyze the problem of the existing ambiguities in the conformal anomaly in theories with an external scalar field in curved backgrounds. In particular, we consider the anomaly of a self-interacting massive scalar field theory and of a Yukawa model in the massless conformal limit. In all cases the ambiguities are related to finite renormalizations of local nonminimal terms in the effective action. We point out the generic nature of this phenomenon and provide a general method to identify the theories where such an ambiguity can arise.

Asorey, M.; Berredo-Peixoto, G. de; Shapiro, I. L. [Departamento de Fisica Teorica, Universidad de Zaragoza, 50009, Zaragoza (Spain); Departamento de Fisica - ICE, Universidade Federal de Juiz de Fora, Juiz de Fora, 36036-330, MG (Brazil)

2006-12-15T23:59:59.000Z

236

Pairs Emission in a Uniform Background Field: an Algebraic Approach  

E-Print Network (OSTI)

A fully algebraic general approach is developed to treat the pairs emission and absorption in the presence of some uniform external background field. In particular, it is shown that the pairs production and annihilation operators, together with the pairs number operator, do actually fulfill the SU(2) functional Lie algebra. As an example of application, the celebrated Schwinger formula is consistently and nicely recovered, within this novel approach, for a Dirac spinor field in the presence of a constant and homogeneous electric field in four spacetime dimensions.

Roberto Soldati

2011-06-23T23:59:59.000Z

237

Revisiting galactic rotation curves given a noncommutative-geometry background  

E-Print Network (OSTI)

It was shown earlier by Rahaman et al. that a noncommutative-geometry background can account for galactic rotation curves without the need for dark matter. The smearing effect that characterizes noncommutative geometry is described by means of a Gaussian distribution intended to replace the Dirac delta function. The purpose of this paper is two-fold: (1) to account for the galactic rotation curves in a more transparent and intuitively more appealing way by replacing the Gaussian function by the simpler Lorentzian distribution proposed by Nozari and Mehdipour and (2) to show that the smearing effect is both a necessary and sufficient condition for meeting the stability criterion.

Kuhfittig, Peter K F

2014-01-01T23:59:59.000Z

238

Accretion onto a black hole in a string cloud background  

E-Print Network (OSTI)

We examine the accretion process onto the black hole with a string cloud background, where the horizon of the black hole has an enlarged radius $r_H=2 M/(1-\\alpha)$, due to the string cloud parameter $\\alpha\\; (0 \\leq \\alpha cloud parameter $\\alpha$. We also find the gas compression ratios and temperature profiles below the accretion radius and at the event horizon. It is shown that the mass accretion rate, for both the relativistic and the non-relativistic fluid by a black hole in the string cloud model, increases with increase in $\\alpha$.

Apratim Ganguly; Sushant G. Ghosh; Sunil D. Maharaj

2014-09-28T23:59:59.000Z

239

Stochastic background of gravitational waves from cosmological sources  

E-Print Network (OSTI)

Gravitational waves (GW) can constitute a unique probe of the primordial universe. In many cases, the characteristic frequency of the emitted GW is directly related to the energy scale at which the GW source is operating in the early universe. Consequently, different GW detectors can probe different energy scales in the evolution of the universe. After a general introduction on the properties of a GW stochastic background of primordial origin, some examples of cosmological sources are presented, which may lead to observable GW signals.

Caprini, Chiara

2015-01-01T23:59:59.000Z

240

First Intrinsic Anisotropy Observations with the Cosmic Background Imager  

E-Print Network (OSTI)

We present the first results of observations of the intrinsic anisotropy of the cosmic microwave background radiation with the Cosmic Background Imager from a site at 5080 m altitude in northern Chile. Our observations show a sharp decrease in C_l in the range l=400 - 1500. The broadband amplitudes we have measured are deltaT(band) = 58.7 (-6.3, +7.7) microK for l = 603 (-166, +180) and 29.7 (-4.2, +4.8) microK for l = 1190 (-224, +261), where these are half-power widths in l. Such a decrease in power at high l is one of the fundamental predictions of the standard cosmological model, and these are the first observations which cover a broad enough l range to show this decrease in a single experiment. The C_l we have measured enable us to place limits on the density parameter, Omega(tot) = 0.7 (90% confidence).

S. Padin; J. K. Cartwright; B. S. Mason; T. J. Pearson; A. C. S. Readhead; M. C. Shepherd; J. Sievers; P. S. Udomprasert; W. L. Holzapfel; S. T. Myers; J. E. Carlstrom; E. M. Leitch; M. Joy; L. Bronfman; J. May

2000-12-11T23:59:59.000Z

Note: This page contains sample records for the topic "foreground background beaver" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Data series subtraction with unknown and unmodeled background noise  

E-Print Network (OSTI)

LISA Pathfinder (LPF), ESA's precursor mission to a gravitational wave observatory, will measure the degree to which two test-masses can be put into free-fall, aiming to demonstrate a residual relative acceleration with a power spectral density (PSD) below 30 fm/s$^2$/Hz$^{1/2}$ around 1 mHz. In LPF data analysis, the measured relative acceleration data series must be fit to other various measured time series data. This fitting is required in different experiments, from system identification of the test mass and satellite dynamics to the subtraction of noise contributions from measured known disturbances. In all cases, the background noise, described by the PSD of the fit residuals, is expected to be coloured, requiring that we perform such fits in the frequency domain. This PSD is unknown {\\it a priori}, and a high accuracy estimate of this residual acceleration noise is an essential output of our analysis. In this paper we present a fitting method based on Bayesian parameter estimation with an unknown frequency-dependent background noise. The method uses noise marginalisation in connection with averaged Welch's periodograms to achieve unbiased parameter estimation, together with a consistent, non-parametric estimate of the residual PSD. Additionally, we find that the method is equivalent to some implementations of iteratively re-weighted least-squares fitting. We have tested the method both on simulated data of known PSD, and to analyze differential acceleration from several experiments with the LISA Pathfinder end-to-end mission simulator.

Stefano Vitale; Giuseppe Congedo; Rita Dolesi; Valerio Ferroni; Mauro Hueller; Daniele Vetrugno; William Joseph Weber; Heather Audley; Karsten Danzmann; Ingo Diepholz; Martin Hewitson; Natalia Korsakova; Luigi Ferraioli; Ferran Gibert; Nikolaos Karnesis; Miquel Nofrarias; Henri Inchauspe; Eric Plagnol; Oliver Jennrich; Paul W. McNamara; Michele Armano; James Ira Thorpe; Peter Wass

2014-04-18T23:59:59.000Z

242

COMPONENTS OF THE EXTRAGALACTIC GAMMA-RAY BACKGROUND  

SciTech Connect

We present new theoretical estimates of the relative contributions of unresolved blazars and star-forming galaxies to the extragalactic {gamma}-ray background (EGB) and discuss constraints on the contributions from alternative mechanisms such as dark matter annihilation and truly diffuse {gamma}-ray production. We find that the Fermi source count data do not rule out a scenario in which the EGB is dominated by emission from unresolved blazars, though unresolved star-forming galaxies may also contribute significantly to the background, within order-of-magnitude uncertainties. In addition, we find that the spectrum of the unresolved star-forming galaxy contribution cannot explain the EGB spectrum found by EGRET at energies between 50 and 200 MeV, whereas the spectrum of unresolved flat spectrum radio quasars, when accounting for the energy-dependent effects of source confusion, could be consistent with the combined spectrum of the low-energy EGRET EGB measurements and the Fermi-Large Area Telescope EGB measurements.

Stecker, Floyd W. [Astrophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Venters, Tonia M., E-mail: floyd.w.stecker@nasa.gov [Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

2011-07-20T23:59:59.000Z

243

Large-Angular-Scale Anisotropy in the Cosmic Background Radiation  

DOE R&D Accomplishments (OSTI)

We report the results of an extended series of airborne measurements of large-angular-scale anisotropy in the 3 K cosmic background radiation. Observations were carried out with a dual-antenna microwave radiometer operating at 33 GHz (.089 cm wavelength) flown on board a U-2 aircraft to 20 km altitude. In eleven flights, between December 1976 and May 1978, the radiometer measured differential intensity between pairs of directions distributed over most of the northern hemisphere with an rms sensitivity of 47 mK Hz{sup 1?}. The measurements how clear evidence of anisotropy that is readily interpreted as due to the solar motion relative to the sources of the radiation. The anisotropy is well fit by a first order spherical harmonic of amplitude 360{+ or -}50km sec{sup -1} toward the direction 11.2{+ or -}0.5 hours of right ascension and 19 {+ or -}8 degrees declination. A simultaneous fit to a combined hypotheses of dipole and quadrupole angular distributions places a 1 mK limit on the amplitude of most components of quadrupole anisotropy with 90% confidence. Additional analysis places a 0.5 mK limit on uncorrelated fluctuations (sky-roughness) in the 3 K background on an angular scale of the antenna beam width, about 7 degrees.

Gorenstein, M. V.; Smoot, G. F.

1980-05-00T23:59:59.000Z

244

THE COSMIC INFRARED BACKGROUND EXPERIMENT (CIBER): THE LOW RESOLUTION SPECTROMETER  

SciTech Connect

Absolute spectrophotometric measurements of diffuse radiation at 1 {mu}m to 2 {mu}m are crucial to our understanding of the radiative content of the universe from nucleosynthesis since the epoch of reionization, the composition and structure of the zodiacal dust cloud in our solar system, and the diffuse galactic light arising from starlight scattered by interstellar dust. The Low Resolution Spectrometer (LRS) on the rocket-borne Cosmic Infrared Background Experiment is a {lambda}/{Delta}{lambda} {approx} 15-30 absolute spectrophotometer designed to make precision measurements of the absolute near-infrared sky brightness between 0.75 {mu}m <{lambda} < 2.1 {mu}m. This paper presents the optical, mechanical, and electronic design of the LRS, as well as the ground testing, characterization, and calibration measurements undertaken before flight to verify its performance. The LRS is shown to work to specifications, achieving the necessary optical and sensitivity performance. We describe our understanding and control of sources of systematic error for absolute photometry of the near-infrared extragalactic background light.

Tsumura, K.; Arai, T.; Matsumoto, T.; Matsuura, S.; Murata, K. [Department of Space Astronomy and Astrophysics, Institute of Space and Astronoutical Science (ISAS), Japan Aerospace Exploration Agency (JAXA), Sagamihara, Kanagawa 252-5210 (Japan); Battle, J.; Bock, J. [Jet Propulsion Laboratory (JPL), National Aeronautics and Space Administration (NASA), Pasadena, CA 91109 (United States); Brown, S.; Lykke, K.; Smith, A. [Optical Technology Division, National Institute of Standards and Technology (NIST), Gaithersburg, MD 20899 (United States); Cooray, A. [Center for Cosmology, University of California, Irvine, Irvine, CA 92697 (United States); Hristov, V.; Levenson, L. R.; Mason, P. [Department of Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States); Keating, B.; Renbarger, T. [Department of Physics, University of California, San Diego, San Diego, CA 92093 (United States); Kim, M. G. [Department of Physics and Astronomy, Seoul National University, Seoul 151-742 (Korea, Republic of); Lee, D. H.; Nam, U. W. [Korea Astronomy and Space Science Institute (KASI), Daejeon 305-348 (Korea, Republic of); Sullivan, I., E-mail: tsumura@ir.isas.jaxa.jp [Department of Physics, The University of Washington, Seattle, WA 98195 (United States); and others

2013-08-15T23:59:59.000Z

245

Determining the Impact of Concrete Roadways on Gamma Ray Background Readings for Radiation Portal Monitoring Systems  

E-Print Network (OSTI)

locations have reported abnormally high gamma background count rates. The higher background data has been attributed, in part, to the concrete surrounding the portal monitors. Higher background can ultimately lead to more material passing through the RPMs...

Ryan, Christopher Michael

2012-07-16T23:59:59.000Z

246

10:30AM TODAY: Senior Administration Officials to Hold a Background...  

Office of Environmental Management (EM)

TODAY: Senior Administration Officials to Hold a Background Conference Call Regarding Oil 10:30AM TODAY: Senior Administration Officials to Hold a Background Conference Call...

247

UBS AG, LONDON BRANCH Order No. EA-263 I. BACKGROUND  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

3 3 I. BACKGROUND Exports of electricity from the United States to a foreign country are regulated and require authorization under section 202(e) of the Federal Power Act (FPA) (16 U.S.C. §824a(e)). On April 11, 2002, the Office of Fossil Energy (FE) of the Department of Energy (DOE) received an application from UBS, AG London Branch (UBS) for authorization to transmit electric energy from the Untied States to Mexico and to Canada. UBS, a Swiss corporation formed in 1998 by the merger of Union Bank of Switzerland and Swiss Bank Corporation, is a power marketer that does not own or control any electric generation or transmission facilities nor does it have any franchised service territory in the United States. The designation "London Branch" indicates the principal booking location of the company's energy trading business; UBS

248

Explanatory Notes Explanatory Notes The EIA-782 Surveys Background  

Gasoline and Diesel Fuel Update (EIA)

Explanatory Notes Explanatory Notes The EIA-782 Surveys Background The EIA-782 surveys were implemented in 1983 to fulfill the data requirements necessary to meet En- ergy Information Administration (EIA) legislative mandates and user community data needs. The re- quirements include petroleum product price, market distribution, demand (or sales), and product supply data, which are needed for a complete evaluation of petroleum market performance. The EIA-782 series includes the Form EIA-782A, "Refiners'/Gas Plant Operators' Monthly Petroleum Product Sales Re- port"; Form EIA-782B, "Resellers'/Retailers' Monthly Petroleum Product Sales Report"; and Form EIA- 782C, "Monthly Report of Prime Supplier Sales of Petroleum Products Sold for Local Consumption."

249

Exelon Generation Company, LLC Order No. EA-249 I. BACKGROUND  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exelon Generation Company, LLC Exelon Generation Company, LLC Order No. EA-249 I. BACKGROUND Exports of electricity from the United States to a foreign country are regulated and require authorization under section 202(e) of the Federal Power Act (FPA) (16 U.S.C. §824a(e)). On August 20, 2001, Exelon Generation Company, LLC (Exelon) applied to the Office of Fossil Energy (FE) of the Department of Energy (DOE) for authorization to transmit electric energy to Canada as a power marketer. Exelon proposes to purchase surplus electric energy from electric utilities and other suppliers within the United States and to export this energy on its own behalf to Canada. The energy to be exported would be delivered to Canada over the international electric transmission facilities owned and operated by the following:

250

ENMAX Energy Marketing Inc. Order No. EA-264 I. BACKGROUND  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

ENMAX Energy Marketing Inc. ENMAX Energy Marketing Inc. Order No. EA-264 I. BACKGROUND Exports of electricity from the United States to a foreign country are regulated and require authorization under section 202(e) of the Federal Power Act (FPA) (16 U.S.C. §824a(e)). On February 20, 2002, the Office of Fossil Energy (FE) of the Department of Energy (DOE) received an application from ENMAX Energy Marketing, Inc. (ENMAX) to transmit electric energy from the United States to Canada. ENMAX is an Alberta corporation having its principal place of business at Calgary, Alberta, Canada. ENMAX is a power marketer and is a wholly-owned subsidiary of ENMAX Energy Corporation, which in turn is a wholly owned subsidiary of ENMAX Corporation. ENMAX currently participates in the wholesale trading of

251

Carbon Sequestration, Media Background Briefing, June 16, 2003  

NLE Websites -- All DOE Office Websites (Extended Search)

Media Background Briefing June 16, 2003 National Energy Technology Laboratory Office of Fossil Energy Scott Klara Carbon Sequestration Product Manager The Fossil Energy Situation Fossil Fuels World's Dominant Energy Source United States 99 QBtu/yr; 85% Fossil Energy World 382 Quads/yr; 86% Fossil Energy Word Data from EIA96. Does not include non-grid-connected biomass. U.S. Data from Table 2 of EIA REA 97 & AEO 2002 Table A2 0.9% Coal 25% Coal 25% Oil 39% Gas 22% Nuclear 6% 7% 7% Coal 22% Gas 24% Nuclear 8% Oil 38% 4% Hydro Solar, Wind, Geo Biomass 3% 0.6% World - 1999 12.8 Trillion kWh - 63% Fossil Energy United States - 1999 3.2 Trillion kWh - 69% Fossil Energy Source: EIA International Energy Outlook 2001 Edison Electric Institute 2001 Renewables Oil Fossil Fuels World's Dominant Electricity Source

252

Testing gaussianity, homogeneity and isotropy with the cosmic microwave background  

E-Print Network (OSTI)

We review the basic hypotheses which motivate the statistical framework used to analyze the cosmic microwave background, and how that framework can be enlarged as we relax those hypotheses. In particular, we try to separate as much as possible the questions of gaussianity, homogeneity and isotropy from each other. We focus both on isotropic estimators of non-gaussianity as well as statistically anisotropic estimators of gaussianity, giving particular emphasis on their signatures and the enhanced "cosmic variances" that become increasingly important as our putative Universe becomes less symmetric. After reviewing the formalism behind some simple model-independent tests, we discuss how these tests can be applied to CMB data when searching for large scale "anomalies"

L. Raul Abramo; Thiago S. Pereira

2010-05-13T23:59:59.000Z

253

Evaluation of Background Mercury Concentrations in the SRS Groundwater System  

SciTech Connect

Mercury analyses associated with the A-01 Outfall have highlighted the importance of developing an understanding of mercury in the Savannah River Site groundwater system and associated surface water streams. This activity is critical based upon the fact that the EPA Ambient Water Quality Criteria (AWQC) for this constituent is 0.012mg/L, a level that is well below conventional detection limits of 0.1 to 0.2 mg/L. A first step in this process is obtained by utilizing the existing investment in groundwater mercury concentrations (20,242 records) maintained in the SRS geographical information management system (GIMS) database. Careful use of these data provides a technically defensible initial estimate for total recoverable mercury in background and contaminated SRS wells.

Looney, B.B.

1999-03-03T23:59:59.000Z

254

Electromagnetic radiation in a time-varying background medium  

E-Print Network (OSTI)

Analytical solutions are presented for the electromagnetic radiation by an arbitrary pulsed source into a homogeneous time-varying background medium. In the constant-impedance case an explicit radiation formula is obtained for the synchronous permittivity and permeability described by any positive function of time. As might be expected, such a medium introduces significant spectral shifts and spatio-temporal modulation, which are analized here for the linear and exponential time-variations of the medium parameters. In the varying-impedance case the solution is obtained for the fourth-order polynomial time-dependence of the permittivity. In addition to the spectral shifts and modulation this spatially homogeneous medium scatters the field introducing causal echoes at the receiver location.

Budko, Neil V

2009-01-01T23:59:59.000Z

255

Background-reducing X-ray multilayer mirror  

DOE Patents (OSTI)

Background-reducing x-ray multilayer mirror. A multiple-layer "wavetrap" deposited over the surface of a layered, synthetic-microstructure soft x-ray mirror optimized for reflectivity at chosen wavelengths is disclosed for reducing the reflectivity of undesired, longer wavelength incident radiation incident thereon. In three separate mirror designs employing an alternating molybdenum and silicon layered, mirrored structure overlaid by two layers of a molybdenum/silicon pair anti-reflection coating, reflectivities of near normal incidence 133, 171, and 186 .ANG. wavelengths have been optimized, while that at 304 .ANG. has been minimized. The optimization process involves the choice of materials, the composition of the layer/pairs as well as the number thereof, and the distance therebetween for the mirror, and the simultaneous choice of materials, the composition of the layer/pairs, and their number and distance for the "wavetrap."

Bloch, Jeffrey J. (Los Alamos, NM); Roussel-Dupre', Diane (Los Alamos, NM); Smith, Barham W. (Los Alamos, NM)

1992-01-01T23:59:59.000Z

256

Weighing the Universe with the Cosmic Microwave Background  

E-Print Network (OSTI)

Variations in $\\Omega$, the total density of the Universe, leave a clear and distinctive imprint on the power spectrum of temperature fluctuations in the cosmic microwave background (CMB). This signature is virtually independent of other cosmological parameters or details of particular cosmological models. We evaluate the precision with which $\\Omega$ can be determined by a CMB map as a function of sky coverage, pixel noise, and beam size. For example, assuming only that the primordial density perturbations were adiabatic and with no prior information on the values of any other cosmological parameters, a full-sky CMB map at $0.5^\\circ$ angular resolution and a noise level of $15\\,\\mu{\\rm K}$ per pixel can determine $\\Omega$ with a variance of 5\\%. If all other cosmological parameters are fixed, $\\Omega$ can be measured to better than 1\\%.

Gerard Jungman; Marc Kamionkowski; Arthur Kosowsky; David N. Spergel

1995-07-21T23:59:59.000Z

257

UBS AG, LONDON BRANCH Order No. EA-261 I. BACKGROUND  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

1 1 I. BACKGROUND Exports of electricity from the United States to a foreign country are regulated and require authorization under section 202(e) of the Federal Power Act (FPA) (16 U.S.C. §824a(e)). On April 11, 2002, the Office of Fossil Energy (FE) of the Department of Energy (DOE) received an application from UBS AG, London Branch (UBS) for authorization to transmit electric energy from the United States to Mexico. UBS, a Swiss corporation formed in 1998 by the merger of Union Bank of Switzerland and Swiss Bank Corporation, is a power marketer that does not own or control any electric generation or transmission facilities nor does it have any franchised service territory in the United States. The designation "London Branch" indicates the

258

Indian Renewable Energy Status Report: Background Report for DIREC 2010  

NLE Websites -- All DOE Office Websites (Extended Search)

Indian Renewable Energy Status Report Indian Renewable Energy Status Report Background Report for DIREC 2010 D. S. Arora (IRADe) | Sarah Busche (NREL) | Shannon Cowlin (NREL) | Tobias Engelmeier (Bridge to India Pvt. Ltd.) | Hanna Jaritz (IRADe) | Anelia Milbrandt (NREL) | Shannon Wang (REN21 Secretariat) NREL/TP-6A20-48948 October 2010 I R A D e NOTICE This report was prepared as an account of work sponsored by an agency of the United States government. Neither the United States government 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 information, apparatus, product, or process disclosed, or represents that its use would not infringe privately

259

Measurement of a Peak in the Cosmic Microwave Background Power  

Science Journals Connector (OSTI)

We describe a measurement of the angular power spectrum of anisotropies in the cosmic microwave background (CMB) at scales of 03 to 5° from the North American test flight of the Boomerang experiment. Boomerang is a balloon-borne telescope with a bolometric receiver designed to map CMB anisotropies on a long-duration balloon flight. During a 6 hr test flight of a prototype system in 1997, we mapped more than 200 deg2 at high Galactic latitudes in two bands centered at 90 and 150 GHz with a resolution of 26' and 165 FWHM, respectively. Analysis of the maps gives a power spectrum with a peak at angular scales of 1° with an amplitude 70 ?KCMB.

P. D. Mauskopf; P. A. R. Ade; P. de Bernardis; J. J. Bock; J. Borrill; A. Boscaleri; B. P. Crill; G. DeGasperis; G. De Troia; P. Farese; P. G. Ferreira; K. Ganga; M. Giacometti; S. Hanany; V. V. Hristov; A. Iacoangeli; A. H. Jaffe; A. E. Lange; A. T. Lee; S. Masi; A. Melchiorri; F. Melchiorri; L. Miglio; T. Montroy; C. B. Netterfield; E. Pascale; F. Piacentini; P. L. Richards; G. Romeo; J. E. Ruhl; E. Scannapieco; F. Scaramuzzi; R. Stompor; N. Vittorio

2000-01-01T23:59:59.000Z

260

Theoretical Backgrounds of the Statistical Methods. Basic Concepts of Probability and Statistics.  

Science Journals Connector (OSTI)

Theoretical Backgrounds of the Statistical Methods. ... Basic Concepts of Probability and Statistics. ...

Henry Scheffe

1951-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "foreground background beaver" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

THE COSMIC NEAR-INFRARED BACKGROUND. II. FLUCTUATIONS  

SciTech Connect

The near-infrared background (NIRB) is one of a few methods that can be used to observe the redshifted light from early stars at a redshift of 6 and above, and thus it is imperative to understand the significance of any detection or nondetection of the NIRB. Fluctuations of the NIRB can provide information on the first structures, such as halos and their surrounding ionized regions in the intergalactic medium (IGM). We combine, for the first time, N-body simulations, radiative transfer code, and analytic calculations of luminosity of early structures to predict the angular power spectrum (C{sub l} ) of fluctuations in the NIRB. We study in detail the effects of various assumptions about the stellar mass, the initial mass spectrum of stars, the metallicity, the star formation efficiency (f{sub *}), the escape fraction of ionizing photons (f{sub esc}), and the star formation timescale (t{sub SF}), on the amplitude as well as the shape of C{sub l} . The power spectrum of NIRB fluctuations is maximized when f{sub *} is the largest (as C{sub l} {proportional_to} f {sup 2}{sub *}) and f{sub esc} is the smallest (as more nebular emission is produced within halos). A significant uncertainty in the predicted amplitude of C{sub l} exists due to our lack of knowledge of t{sub SF} of these early populations of galaxies, which is equivalent to our lack of knowledge of the mass-to-light ratio of these sources. We do not see a turnover in the NIRB angular power spectrum of the halo contribution, which was claimed to exist in the literature, and explain this as the effect of high levels of nonlinear bias that was ignored in the previous calculations. This is partly due to our choice of the minimum mass of halos contributing to NIRB ({approx}2 x 10{sup 9} M{sub sun}), and a smaller minimum mass, which has a smaller nonlinear bias, may still exhibit a turnover. Therefore, our results suggest that both the amplitude and shape of the NIRB power spectrum provide important information regarding the nature of sources contributing to the cosmic reionization. The angular power spectrum of the IGM, in most cases, is much smaller than the halo angular power spectrum, except when f{sub esc} is close to unity, t{sub SF} is longer, or the minimum redshift at which the star formation is occurring is high. In addition, low levels of the observed mean background intensity tend to rule out high values of f{sub *} {approx}> 0.2.

Fernandez, Elizabeth R. [Center for Astrophysics and Space Astronomy, University of Colorado, 389 UCB, Boulder, CO 80309-0389 (United States); Komatsu, Eiichiro; Shapiro, Paul R. [Texas Cosmology Center and the Department of Astronomy, University of Texas at Austin, 1 University Station, C1400, Austin, TX 78712 (United States); Iliev, Ilian T., E-mail: elizabeth.fernandez@colorado.ed [Astronomy Centre, Department of Physics and Astronomy, Pevensey II Building, University of Sussex, Falmer, Brighton BN1 9QH (United Kingdom)

2010-02-20T23:59:59.000Z

262

Kinematics of geodesic flows in stringy black hole backgrounds  

E-Print Network (OSTI)

We study the kinematics of timelike geodesic congruences in two and four dimensions in spacetime geometries representing stringy black holes. The Raychaudhuri equations for the kinematical quantities (namely, expansion, shear and rotation) characterising such geodesic flows are written down and subsequently solved analytically (in two dimensions) and numerically (in four dimensions) for specific geodesics flows. We compare between geodesic flows in dual (electric and magnetic) stringy black hole backgrounds in four dimensions, by showing the differences that arise in the corresponding evolutions of the kinematic variables. The crucial role of initial conditions and the spacetime curvature on the evolution of the kinematical variables is illustrated. Some novel general conclusions on geodesic focusing are obtained from the analytical and numerical findings. We also propose new quantifiers in terms of (a) the time (affine parameter) of approach to a singularity and (b) the location of extrema in the functional evolution of the kinematic variables, which may be used to distinguish between flows in different geometries. In summary, our quantitative findings bring out hitherto unknown features of the kinematics of geodesic flows, which, otherwise, would have remained overlooked, if we confined ourselves to only a qualitative analysis.

Anirvan Dasgupta; Hemwati Nandan; Sayan Kar

2009-06-12T23:59:59.000Z

263

Project Lyman: Quantifying 11 Gyrs of Metagalactic Ionizing Background Evolution  

E-Print Network (OSTI)

The timing and duration of the reionization epoch is crucial to the emergence and evolution of structure in the universe. The relative roles that star-forming galaxies, active galactic nuclei and quasars play in contributing to the metagalactic ionizing background across cosmic time remains uncertain. Deep quasar counts provide insights into their role, but the potentially crucial contribution from star-formation is highly uncertain due to our poor understanding of the processes that allow ionizing radiation to escape into the intergalactic medium (IGM). The fraction of ionizing photons that escape from star-forming galaxies is a fundamental free parameter used in models to "fine-tune" the timing and duration of the reionization epoch that occurred somewhere between 13.4 and 12.7 Gyrs ago (redshifts between 12 > z > 6). However, direct observation of Lyman continuum (LyC) photons emitted below the rest frame \\ion{H}{1} ionization edge at 912 \\AA\\ is increasingly improbable at redshifts z > 3, due to the stead...

McCandliss, Stephan R; Bergvall, Nils; Bianchi, Luciana; Bridge, Carrie; Bogosavljevic, Milan; Cohen, Seth H; Deharveng, Jean-Michel; Dixon, W Van Dyke; Ferguson, Harry; Friedman, Peter; Hayes, Matthew; Howk, J Christopher; Inoue, Akio; Iwata, Ikuru; Kaiser, Mary Elizabeth; Kriss, Gerard; Kruk, Jeffrey; Kutyrev, Alexander S; Leitherer, Claus; Meurer, Gerhardt R; Prochaska, Jason X; Sonneborn, George; Stiavelli, Massimo; Teplitz, Harry I; Windhorst, Rogier A

2012-01-01T23:59:59.000Z

264

Reissner-Nordstrom black hole in dark energy background  

E-Print Network (OSTI)

In this paper we propose a stationary solution of Einstein's field equations describing Reissner-Nordstrom black hole in dark energy background. It is to be regarded as the Reissner-Nordstrom black hole is embedded into the dark energy solution producing Reissner-Nordstrom-dark energy black hole. We find that the space-time geometry of Reissner-Nordstrom-dark energy solution is Petrov type $D$ in the classification of space-times. It is also shown that the embedded space-time possesses an energy-momentum tensor of the electromagnetic field interacting with the dark energy having negative pressure. We find the energy-momentum tensor for dark energy violates the the strong energy condition due to the negative pressure, whereas that of the electromagnetic field obeys the strong energy condition. It is shown that the time-like vector field for an observer in the Reissner-Nordstrom-dark energy space is expanding, accelerating, shearing and non-rotating. We investigate the surface gravity of the horizons for the embedded dark energy black hole. The characteristic properties of relativistic dark energy based on the de Sitter solution is discussed in an appendix.

Ngangbam Ishwarchandra; Ng. Ibohal; K. Yugindro Singh

2014-11-29T23:59:59.000Z

265

Cosmological-Parameter Determination with Microwave Background Maps  

E-Print Network (OSTI)

The angular power spectrum of the cosmic microwave background (CMB) contains information on virtually all cosmological parameters of interest, including the geometry of the Universe ($\\Omega$), the baryon density, the Hubble constant ($h$), the cosmological constant ($\\Lambda$), the number of light neutrinos, the ionization history, and the amplitudes and spectral indices of the primordial scalar and tensor perturbation spectra. We review the imprint of each parameter on the CMB. Assuming only that the primordial perturbations were adiabatic, we use a covariance-matrix approach to estimate the precision with which these parameters can be determined by a CMB temperature map as a function of the fraction of sky mapped, the level of pixel noise, and the angular resolution. For example, with no prior information about any of the cosmological parameters, a full-sky CMB map with $0.5^\\circ$ angular resolution and a noise level of 15 $\\mu$K per pixel can determine $\\Omega$, $h$, and $\\Lambda$ with standard errors of $\\pm0.1$ or better, and provide determinations of other parameters which are inaccessible with traditional observations. Smaller beam sizes or prior information on some of the other parameters from other observations improves the sensitivity. The dependence on the the underlying cosmological model is discussed.

Gerard Jungman; Marc Kamionkowski; Arthur Kosowsky; David N. Spergel

1996-05-23T23:59:59.000Z

266

The companion candidate near Fomalhaut - a background neutron star?  

E-Print Network (OSTI)

The directly detected planetary mass companion candidate close to the young, nearby star Fomalhaut is a subject of intense discussion. While the detection of common proper motion led to the interpretation as Jovian-mass companion, later non-detections in the infrared raised doubts. Recent astrometric measurements indicate a belt crossing or highly eccentric orbit for the object, if a companion, making the planetary interpretation potentially even more problematic. In this study we discuss the possibility of Fomalhaut\\,b being a background object with a high proper motion. By analysing the available photometric and astrometric data of the object, we show that they are fully consistent with a neutron star: Neutron stars are faint, hot (blue), and fast moving. Neutron stars with an effective temperature of the whole surface area being 112,000 K to 126,500 K (with small to negligible extinction) at a distance of roughly 11 pc (best fit) would be consistent with all observables, namely with the photometric detecti...

Neuhaeuser, Ralph; Ginski, Christian; Schmidt, Janos; Hambaryan, Valeri; Schmidt, Tobias

2015-01-01T23:59:59.000Z

267

Non-linear evolution of the cosmic neutrino background  

SciTech Connect

We investigate the non-linear evolution of the relic cosmic neutrino background by running large box-size, high resolution N-body simulations which incorporate cold dark matter (CDM) and neutrinos as independent particle species. Our set of simulations explore the properties of neutrinos in a reference ?CDM model with total neutrino masses between 0.05-0.60 eV in cold dark matter haloes of mass 10{sup 11}?10{sup 15} h{sup ?1}M{sub s}un, over a redshift range z = 0?2. We compute the halo mass function and show that it is reasonably well fitted by the Sheth-Tormen formula, once the neutrino contribution to the total matter is removed. More importantly, we focus on the CDM and neutrino properties of the density and peculiar velocity fields in the cosmological volume, inside and in the outskirts of virialized haloes. The dynamical state of the neutrino particles depends strongly on their momentum: whereas neutrinos in the low velocity tail behave similarly to CDM particles, neutrinos in the high velocity tail are not affected by the clustering of the underlying CDM component. We find that the neutrino (linear) unperturbed momentum distribution is modified and mass and redshift dependent deviations from the expected Fermi-Dirac distribution are in place both in the cosmological volume and inside haloes. The neutrino density profiles around virialized haloes have been carefully investigated and a simple fitting formula is provided. The neutrino profile, unlike the cold dark matter one, is found to be cored with core size and central density that depend on the neutrino mass, redshift and mass of the halo, for halos of masses larger than ? 10{sup 13.5}h{sup ?1}M{sub s}un. For lower masses the neutrino profile is best fitted by a simple power-law relation in the range probed by the simulations. The results we obtain are numerically converged in terms of neutrino profiles at the 10% level for scales above ? 200 h{sup ?1}kpc at z = 0, and are stable with respect to box-size and starting redshift of the simulation. Our findings are particularly important in view of upcoming large-scale structure surveys, like Euclid, that are expected to probe the non-linear regime at the percent level with lensing and clustering observations.

Villaescusa-Navarro, Francisco; Viel, Matteo [INAF/Osservatorio Astronomico di Trieste, Via Tiepolo 11, 34143, Trieste (Italy); Bird, Simeon [Institute for Advanced Study, 1 Einstein Drive, Princeton, NJ, 08540 (United States); Peña-Garay, Carlos, E-mail: villaescusa@oats.inaf.it, E-mail: spb@ias.edu, E-mail: penya@ific.uv.es, E-mail: viel@oats.inaf.it [Instituto de Física Corpuscular, CSIC-UVEG, E-46071, Paterna, Valencia (Spain)

2013-03-01T23:59:59.000Z

268

Narrative Foreground in the Plays of Osvaldo Dragún  

E-Print Network (OSTI)

the audience is prepared for an experience of storytelling, that is, of narration. Robyn Lutz notes that "the consciousness of audience is always present, with the result that the tale never becomes a you-were-there reliving of past events" (31). David... Foster points out that the audience of Historias "proporciona tanto la sustancia semántica de la obra como su validación lingüística en la medida en que el receptor justifica la presencia del mensaje" (134). The first story, "Historia de un flemón, una...

Gladhart, Amalia

1993-04-01T23:59:59.000Z

269

A Device to Evaluate Broadcast Background Sound Balance Using Loudness for Elderly Listeners  

Science Journals Connector (OSTI)

Elderly people complain that they sometimes have a hard time hearing the narration of broadcast TV programs because the background sounds (background music, sound effects) are too loud. We conducted subjective...

Tomoyasu Komori; Tohru Takagi…

2010-01-01T23:59:59.000Z

270

Graphene as a protein crystal mounting material to reduce background scatter  

Science Journals Connector (OSTI)

A new method is presented to reduce background scatter by use of graphene-based mounting of protein crystals.

Wierman, J.L.

2013-08-03T23:59:59.000Z

271

524 IEEE Transactionson Nuclear Science, Vol. 35, No. 1, February 1988 BACKGROUND EVENTS IN MICROCHANNEL PLATES  

E-Print Network (OSTI)

524 IEEE Transactionson Nuclear Science, Vol. 35, No. 1, February 1988 BACKGROUND EVENTS of the MCP's are found to have no significant effect on the background rate. Detection of 1.46 MeV y rays the environmental or operating conditions must be used to investigate the behavior of the intrinsic MCP background

Wargelin, Bradford J.

272

Variability in surface ozone background over the United States: Implications for air quality policy  

E-Print Network (OSTI)

Variability in surface ozone background over the United States: Implications for air quality policy background over the United States: Implications for air quality policy, J. Geophys. Res., 108(D24), 4787, doi Agency (EPA) accounts for a background O3 level above which risk to human health is assessed. Since

Liu, Hongyu

273

Background and Related Work Data Encoding for Failure-Prone Sensor Networks  

E-Print Network (OSTI)

Outline Background and Related Work Data Encoding for Failure-Prone Sensor Networks Encoding for Persistent Sensor Networks #12;Outline Background and Related Work Data Encoding for Failure-Prone Sensor Networks Outline 1 Background and Related Work Sensor Networks Failures in Sensor Networks Data Transfer

274

Graphene Nucleation Density on Copper: Fundamental Role of Background Pressure Ivan Vlassiouk,*  

E-Print Network (OSTI)

1 Graphene Nucleation Density on Copper: Fundamental Role of Background Pressure Ivan Vlassiouk the effect of background pressure and synthesis temperature on the graphene crystal sizes in chemical vapor of the background pressure and provide the activation energy for graphene nucleation in atmospheric pressure CVD (9

Feenstra, Randall

275

Establishment of a Background Environmental Monitoring Station for the PNNL Campus  

SciTech Connect

The environmental surveillance of background levels of radionuclides and, in particular, the siting of a background environmental surveillance (monitoring) station are examined. Many published works identify and stress the need for background monitoring; however, little definitive and comprehensive information for siting a station exists. A definition of an ideal background monitoring location and the generic criteria recommended for use in establishing such a background monitoring location are proposed. There are seven primary (mandatory) criteria described with two additional, optional criteria. The criteria are applied to the Richland, Washington (WA), Pacific Northwest National Laboratory (PNNL) Campus, which currently uses background monitoring data from the nearby Hanford Site. Eleven potential background monitoring sites were identified, with one location in Benton City, WA found to meet all of the mandatory and optional criteria. It is expected that the new sampler will be installed and operating by the end of June, 2015.

Fritz, Brad G.; Snyder, Sandra F.; Barnett, J. M.; Bisping, Lynn E.; Rishel, Jeremy P.

2014-12-18T23:59:59.000Z

276

10:30AM TODAY: Senior Administration Officials to Hold a Background  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

0:30AM TODAY: Senior Administration Officials to Hold a Background 0:30AM TODAY: Senior Administration Officials to Hold a Background Conference Call Regarding Oil 10:30AM TODAY: Senior Administration Officials to Hold a Background Conference Call Regarding Oil June 23, 2011 - 12:00am Addthis WASHINGTON, DC - Today, Thursday, June 23 at 10:30AM ET, Senior Administration Officials will hold a background conference call regarding the ongoing oil supply disruptions in the Middle East and North Africa and the announcement this morning to release oil from the Strategic Petroleum Reserve in coordination with the International Energy Agency. The call will be on background with no embargo. WHO: Senior Administration Officials WHAT: Background conference call WHEN: Thursday, June 23, 2011 10:30AM ET RSVP: Media who want to attend this call should dial (877) 941-1706 and ask to join the "White House call." No passcode is necessary.

277

Possible generation of $?$-ray laser by electrons wiggling in a background laser  

E-Print Network (OSTI)

The possibility of $\\gamma-$ray laser generation by the radiation of wiggling electrons in an usual background laser is discussed.

Qi-Ren Zhang

2014-08-13T23:59:59.000Z

278

Determination of QCD Backgrounds in ATLAS: A challenge for SUSY searches  

E-Print Network (OSTI)

In this paper we briefly discuss the estimation of uncertainties in QCD backgrounds to searches for Supersymmetry under development by the ATLAS collaboration.

B. Meirose

2009-09-24T23:59:59.000Z

279

Food and Health in Everyday Life: A Qualitative Study with Children from Contrasting Backgrounds.  

E-Print Network (OSTI)

??Background Children's relationships with food are high on the research and policy agenda of many nations, driven by the global issue of childhood obesity. However,… (more)

Fairbrother, Hannah

2013-01-01T23:59:59.000Z

280

Background Story  

NLE Websites -- All DOE Office Websites (Extended Search)

Checking for Candidate Events Checking for Candidate Events The Tevatron produces millions of collisions each second at CDF and DZero. The detectors detect most but not all of these collisions. When a collision is detected, computers must decide if the event is an interesting one for the current study. (While this decision is being made, the detector cannot process another event. Also, the detector needs a little time to recover from one event before detecting another. That is why the detector cannot detect all the collisions. Physicists try to minimize this down time.) To decide if an event is interesting, computers perform a quick preliminary data analysis looking for certain characteristics. This is done in a series of tests. Only if the event passes these tests does it "trigger" the

Note: This page contains sample records for the topic "foreground background beaver" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Legal Background  

Office of Legacy Management (LM)

Summary of Summary of Property Damage Complaints andlor Claims \ P R O J E C T R U L I S O N I - S U M M A R Y O F P R O P E R T Y D A M A G E C O M P L A I N T S A N D / O R C L A I M S AS OF MARCH 31, 1970 'E: The m a t e r i a l contained h e r e i n i s n o t t o be p u b l i c l y d i s t r i b u t e d w i t h o u t t h e p r i o r Office ( ~ E c ) , y o @ oplc-9 - Las Vegas, Nevada 89114 -- Prepared By: % & c n U a i l b 0. Brush Approved: Las Vegas Branch General Adjustment Bureau, Inc. P r o j e c t R u l i s o n Summary o f Property Damage Complaints and/or Claims DISTRIBUTION: H. E. G r i e r , President, CER Geonuclear Corp., Las Vegas, Nev. (4) G. W. Frank, A u s t r a l O i l Co., Houston, Texas (4) W. E. Ogle, LASL, Los Alamos, N. !4. (2) H. L. Reynolds, LRL, Livermore, C a l i f . ( 2 ) Fred Holzer/Gene C. Rizer, LRL, Livermore, C a l i f . ( 2 ) L l o v d A. Lee, J. A. Blume & Assoc.. San Francisco. C

282

Legal Background  

Office of Legacy Management (LM)

Text of Decision Text of Decision March 16,1970 DISCLAIMER Portions of this document may be illegible in electronic image products. Images are produced from the best available original document. PROJECT RULlSON L .. .. ---_ ---._._ /' Text of Decision March 76, 7970 Q - CHIEF JUDGE ALFRED A. ARRAJ United States District Court Denver, Colorado With Introductory Remarks By ROBERT E. MILLER Manager k v a d a Operations ~ffice:,>:?.;, .- ,.,:-. !c- - United states Atomic Energy Commission i. This page intentionally left blank UNITED STATES ATOMIC ENERGY COMMISSION N E V A D A O P E R A T I O N S O F F I C E P. 0. e o x 14100 L A S V E G A S . N E V A D A 891 1 4 June ,1970 The P r o j e c t Rulison d e t o n a t i o n was conducted i n Western Colorado on September 10, 1969 as p a r t of a j o i n t g o v e r n m e n t - i n d u s t r y e x

283

Historical background  

Science Journals Connector (OSTI)

...human trial of a vaccine of this type (Gilbert 1999). Another event in EBV research...Marek's disease, current topics in microbiology and immunology (ed. K. Hirai), pp...Japan Pathol. Soc. 20, 3^38. Gilbert, K. 1999 Results of a phase 1 clinical...

2001-01-01T23:59:59.000Z

284

Background T  

NLE Websites -- All DOE Office Websites (Extended Search)

quality, navigation, recreation, cultural resources, fish protection operations and ecosystem function needs, as well as potential effects of climate change. The U.S. Entity and...

285

LArGe - Active background suppression using argon scintillation for the GERDA $0\  

E-Print Network (OSTI)

LArGe is a GERDA low-background test facility to study novel background suppression methods in a low-background environment, for future application in the GERDA experiment. Similar to GERDA, LArGe operates bare germanium detectors submersed into liquid argon (1 m$^3$, 1.4 tons), which in addition is instrumented with photomultipliers to detect argon scintillation light. The scintillation signals are used in anti-coincidence with the germanium detectors to effectively suppress background events that deposit energy in the liquid argon. The background suppression efficiency was studied in combination with a pulse shape discrimination (PSD) technique using a BEGe detector for various sources, which represent characteristic backgrounds to GERDA. Suppression factors of a few times $10^3$ have been achieved. First background data of LArGe with a coaxial HPGe detector (without PSD) yield a background index of (0.12$-$4.6)$\\cdot 10^{-2}$ cts/(keV$\\cdot$kg$\\cdot$y) (90% C.L.), which is at the level of GERDA Phase I. Fu...

Agostini, M; Budjáš, D; Cattadori, C; Gangapshev, A; Gusev, K; Heisel, M; Junker, M; Klimenko, A; Lubashevskiy, A; Pelczar, K; Schönert, S; Smolnikov, A; Zuzel, G

2015-01-01T23:59:59.000Z

286

Fast Illumination-invariant Background Subtraction using Two Views: Error Analysis, Sensor Placement and Applications  

E-Print Network (OSTI)

Fast Illumination-invariant Background Subtraction using Two Views: Error Analysis, Sensor£ Abstract Background modeling and subtraction to detect new or moving objects in a scene is an important a detailed analysis of such errors. Then, we propose a sensor configuration that eliminates false de

Paragios, Nikos

287

Studies of Neutron Backgrounds for PoGOLite a Balloon-borne Gamma-ray Polarimeter  

E-Print Network (OSTI)

Studies of Neutron Backgrounds for PoGOLite ­ a Balloon-borne Gamma-ray Polarimeter Jaroslav, neutrons stars and jets from active galaxies. To this day, polarisation has only been measured for the Crab, performed using Monte Carlo simulations in Geant4, of the atmospheric neutron background and its effect

Haviland, David

288

The Impact of Background Error on Incomplete Observations for 4D-Var Data Assimilation with  

E-Print Network (OSTI)

The Impact of Background Error on Incomplete Observations for 4D-Var Data Assimilation with the FSU on the 4D- Var data assimilation, twin experiments were carried out with the dy- namical core of the new is also investigated. Keywords: Data assimilation, incomplete observations, background error. 1

Navon, Michael

289

Using Background Knowledge to Rank Itemsets Nikolaj Tatti and Michael Mampaey  

E-Print Network (OSTI)

for more flexible approaches for infus- ing background knowledge. Namely, we show that we can efficiently that these statistics describe forms of data that occur in practice and have been studied in data mining. To infuse-first search strate- gies [2,21]. The drawback of frequency is that we cannot infuse any background knowledge

290

SLAC-PUB-11691 Simulation of PEP-II Accelerator Backgrounds Using TURTLE  

E-Print Network (OSTI)

SLAC-PUB-11691 Simulation of PEP-II Accelerator Backgrounds Using TURTLE Work supported;SIMULATION OF PEP-II ACCELERATOR BACKGROUNDS USING TURTLE R. Barlow, Manchester University, Manchester, UK WBar detector at the SLAC B-Factory, carried out using LPTURTLE, a modified version of the DECAY TURTLE

Paris-Sud XI, Université de

291

Predicted X-ray backgrounds for the International X-ray Observatory  

E-Print Network (OSTI)

The background that will be observed by IXO's X-ray detectors naturally separates into two components: (1) a Cosmic X-ray Background (CXB), primarily due to unresolved point sources at high energies (E>2 keV), along with ...

Bautz, Marshall W.

292

Audio-video integration for background Marco Cristani, Manuele Bicego, and Vittorio Murino  

E-Print Network (OSTI)

Audio-video integration for background modelling Marco Cristani, Manuele Bicego, and Vittorio of surveillance, namely, audio-visual data integration for background modelling. Actually, visual data acquired by a fixed camera can be easily supported by audio infor- mation allowing a more complete analysis

Cristani, Marco

293

Derivation of 24-Hour Average SO2, Background for the Update 1 Report |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Derivation of 24-Hour Average SO2, Background for the Update 1 Derivation of 24-Hour Average SO2, Background for the Update 1 Report Derivation of 24-Hour Average SO2, Background for the Update 1 Report Docket No. EO-05-01. As supporting documentation for "Update 1 to: A Dispersion Modeling Analysis of Downwash from Mirant's Potomac River Power Plant: Modeling Unit 1 Emissions in a Cycling Mode" this memo documents the fact that the observed 24-hour SO2 background concentrations during periods when meteorological conditions produce the highest impacts from Unit 1. Derivation of 24-Hour Average SO2, Background for the Update 1 Report More Documents & Publications Review of the ENSR Report Titled "Update 1 to: A Dispersion Modeling Analysis of Downwash from Mirant's Potomac River Power Plant"

294

Effect of Background Emissivity on Gas Detection in Thermal Hyperspectral Imagery  

SciTech Connect

Detecting and identifying weak gaseous plumes using thermal imaging data is complicated by many factors. These include variability due to atmosphere, ground and plume temper- ature, and background clutter. This paper presents an analysis of one formulation of the physics-based radiance model, which describes at-sensor observed radiance. The background emissivity and plume/ground temperatures are isolated, and their effects on net chemical signal are described. This analysis shows that the plume’s physical state, emission or absorption, is directly dependent on the background emissivity. It then describes what conditions on the background emissivity have inhibiting effects on the net chemical signal. These claims are illustrated by analyzing synthetic hyperspectral imaging data with the Adaptive Matched Filter using four chemicals and three distinct background emissivities. Two chemicals (Carbontetrachloride and Tetraflourosilane) in the analysis had a very strong relationship with the background emissivities: they exhibited absorbance over a small range of wavenumbers and the background emissivities showed a consistent ordering at these wavenumbers. Analysis of simulated hyperspectral images containing these chemicals showed complete agreement with the analysis of the physics-based model that described when the background emissivities would have inhibiting effects on gas detection. The other chemicals considered (Ammonia and Tributylphosphate) exhibited very complex absorbance structure across the longwave infrared spectrum. Analysis of images containing these chemicals revealed that the the analysis of the physics-based model did not hold completely for these complex chemicals but did suggest that gas detection was dominated by their dominant absorbance features. These results provide some explanation of the effect of the background emissivity on gas detection and a more general exploration of gas absorbance/background emissivity variability and their effects on gas detection is warranted. i

Walsh, Stephen J.; Tardiff, Mark F.; Chilton, Lawrence K.; Metoyer, Candace N.

2008-10-02T23:59:59.000Z

295

Gravitational-wave stochastic background from kinks and cusps on cosmic strings  

Science Journals Connector (OSTI)

We compute the contribution of kinks on cosmic string loops to stochastic background of gravitational waves (SBGW). We find that kinks contribute at the same order as cusps to the SBGW. We discuss the accessibility of the total background due to kinks as well as cusps to current and planned gravitational-wave detectors, as well as to the big bang nucleosynthesis (BBN), the cosmic microwave background (CMB), and pulsar timing constraints. As in the case of cusps, we find that current data from interferometric gravitational-wave detectors, such as LIGO, are sensitive to areas of parameter space of cosmic string models complementary to those accessible to pulsar, BBN, and CMB bounds.

S. Ölmez; V. Mandic; X. Siemens

2010-05-13T23:59:59.000Z

296

The number counts and infrared backgrounds from infrared-bright galaxies  

SciTech Connect

Extragalactic number counts and diffuse backgrounds at 25, 60, and 100 microns are predicted using new luminosity functions and improved spectral-energy distribution density functions derived from IRAS observations of nearby galaxies. Galaxies at redshifts z less than 3 that are like those in the local universe should produce a minimum diffuse background of 0.0085, 0.038, and 0.13 MJy/sr at 25, 60, and 100 microns, respectively. Models with significant luminosity evolution predict backgrounds about a factor of 4 greater than this minimum. 22 refs.

Hacking, P.B.; Soifer, B.T. (JPL, Pasadena, CA (USA) California Institute of Technology, Pasadena (USA))

1991-02-01T23:59:59.000Z

297

Low-background underground facilities for the direct detection of dark matter  

SciTech Connect

This is the report of a working group formed to discuss the requirements of an underground facility for experiments trying to detect directly dark matter particles. There is a brief discussion of the general properties of underground facilities, focusing on the levels of muon induced backgrounds that are tolerable. Then the authors review the scientific motivation of the search for dark matter particles, and the existing experimental limits. There is a short description of the shielding necessary to reach the desired background levels. Finally, they report the results of their preliminary study of muon induced backgrounds in dark matter experiments, and the implications for the required depth of the facilities for such experiments.

Barnes, P.D. Jr. [Univ. of California, Berkeley, CA (United States); [Center for Particle Astrophysics, Berkeley, CA (United States); Caldwell, D. [Univ. of California, Santa Barbara, CA (United States); DaSilva, A. [Center for Particle Astrophysics, Berkeley, CA (United States)] [and others

1992-12-31T23:59:59.000Z

298

CHEMICAL WEAPONS CONVENTION BULLETIN News, Background and Comment on Chemical and Biological Warfare Issues  

E-Print Network (OSTI)

CHEMICAL WEAPONS CONVENTION BULLETIN News, Background and Comment on Chemical and Biological DUPLICATION Graham S Pearson HSP Advisory Board The Biological and Toxin Weapons Convention (BTWC) was opened biological weapons and prohibit their development, produc- tion, stockpiling, acquisition and retention

Sussex, University of

299

A STOCHASTIC LEARNING ALGORITHM FOR PIXEL-LEVEL BACKGROUND MODELS Nick Mould and Joseph P. Havlicek  

E-Print Network (OSTI)

A STOCHASTIC LEARNING ALGORITHM FOR PIXEL-LEVEL BACKGROUND MODELS Nick Mould and Joseph P. Havlicek of merit, probability correct classification (PrCC), presented here for the first time. Index Terms-- video

Havlicek, Joebob

300

Background-subtraction using contour-based fusion of thermal and visible imagery  

E-Print Network (OSTI)

rights reserved. Keywords: Background-subtraction; Fusion; Thermal imagery; Infrared; FLIR; Contour of the electromagnetic spectrum, long-wave infrared (thermal) and visible light. Thermal (FLIR) and color video cameras

Davis, James W.

Note: This page contains sample records for the topic "foreground background beaver" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

2.8 Carbon Nanotubes (Fullerenes) 2.8.1 Background  

E-Print Network (OSTI)

85 2.8 Carbon Nanotubes (Fullerenes) 2.8.1 Background After long being available only in research or apparently under consideration, though the concept has been discussed. Carbon nanotubes and fullerenes

302

Levinson’s theorem for Dirac particles moving in a background magnetic monopole field  

Science Journals Connector (OSTI)

A generalized Levinson’s theorem for a Dirac particle moving in a background magnetic monopole field is derived. The phase shifts are defined from the phases of appropriate combinations of the radial functions at infinity.

Zhong-Qi Ma

1985-10-15T23:59:59.000Z

303

Estimating background concentrations of inorganic analytes from on-site soil sample data  

SciTech Connect

At Superfund sites, regulatory agencies have commonly required that an extensive off-site study be performed to identify background concentrations of chemicals of concern in the sample medium for the purpose of establishing action levels. However, in an effort to save time and money, graphic statistics were used to estimate background concentrations of inorganic chemicals from 127 on-site soil samples collected at Andersen Air Force Base, a Superfund site on Guam. The statistical method used for this evaluation utilized probability plots, and was a modification of a technique used in mineral exploration to identify anomalous and background geochemical data. This paper provides an overview of the modified statistical method and its application at Andersen Air Force Base, and the results of the evaluation, including estimated background concentrations.

Cook, P.D. [ICF Kaiser Engineers, Inc., Pittsburgh, PA (United States)

1998-12-31T23:59:59.000Z

304

An upper bound from helioseismology on the stochastic background of gravitational waves  

E-Print Network (OSTI)

The universe is expected to be permeated by a stochastic background of gravitational radiation of astrophysical and cosmological origin. This background is capable of exciting oscillations in solar-like stars. Here we show that solar-like oscillators can be employed as giant hydrodynamical detectors for such a background in the muHz to mHz frequency range, which has remained essentially unexplored until today. We demonstrate this approach by using high-precision radial velocity data for the Sun to constrain the normalized energy density of the stochastic gravitational-wave background around 0.11 mHz. These results open up the possibility for asteroseismic missions like CoRoT and Kepler to probe fundamental physics.

Daniel M. Siegel; Markus Roth

2014-01-27T23:59:59.000Z

305

Gator: a low-background counting facility at the Gran Sasso Underground Laboratory  

E-Print Network (OSTI)

A low-background germanium spectrometer has been installed and is being operated in an ultra-low background shield (the Gator facility) at the Gran Sasso underground laboratory in Italy (LNGS). With an integrated rate of ~0.16 events/min in the energy range between 100-2700 keV, the background is comparable to those of the world's most sensitive germanium detectors. After a detailed description of the facility, its background sources as well as the calibration and efficiency measurements are introduced. Two independent analysis methods are described and compared using examples from selected sample measurements. The Gator facility is used to screen materials for XENON, GERDA, and in the context of next-generation astroparticle physics facilities such as DARWIN.

Baudis, L; Askin, A; Angle, J; Aprile, E; Bruch, T; Kish, A; Laubenstein, M; Manalaysay, A; Undagoitia, T Marrodan; Schumann, M

2011-01-01T23:59:59.000Z

306

An Adaptive Approach to Mitigate Background Covariance Limitations in the Ensemble Kalman Filter  

Science Journals Connector (OSTI)

A new approach is proposed to address the background covariance limitations arising from undersampled ensembles and unaccounted model errors in the ensemble Kalman filter (EnKF). The method enhances the representativeness of the EnKF ensemble by ...

Hajoon Song; Ibrahim Hoteit; Bruce D. Cornuelle; Aneesh C. Subramanian

2010-07-01T23:59:59.000Z

307

b¯bx and W??? backgrounds for the UA1 monojet signal  

Science Journals Connector (OSTI)

Backgrounds from W??? and b¯bx, via the leptonic decay channel Bc???, may account for three out of the five UA1 monojet events with ?EM>40 GeV.

R. Odorico

1985-12-01T23:59:59.000Z

308

Simulation of Radiation Backgrounds associated with the HEXRI Diagnostics at the National Ignition Facility  

SciTech Connect

Experiments resulting in a significant neutron yield are scheduled to start in 2010 at the National Ignition Facility (NIF). A wide range of diagnostics will be used to measure several parameters of implosion such as the core and fuel shape, temperatures and densities, and neutron yield. Accurate evaluations of the neutron and gamma backgrounds are important for several diagnostics, such as the High Energy X-ray Imager (HEXRI). Several Monte-Carlo simulations were performed to identify the expected signal to background ratios at several potential locations for the HEXRI diagnostics. Gamma backgrounds were significantly reduced by using tungsten collimators. The collimators resulted in the reduction of the gamma background at the HEXRI scintillators by more than an order of magnitude during the first 40 ns following a THD shot.

Khater, H; Dauffy, L; Tommasini, R; Eckart, M; Eder, D

2009-10-05T23:59:59.000Z

309

SPECTROPHOTOMETRIC DETERMINATION OF Fe IN DRINKING WATER Background Reading: Harris, 7th  

E-Print Network (OSTI)

SPECTROPHOTOMETRIC DETERMINATION OF Fe IN DRINKING WATER Background Reading: Harris, 7th ed., Chap contaminants in drinking water can be determined spectrophotometrically, including iron. Although iron the iron content of drinking water to

Weston, Ken

310

Access to health care for individuals with developmental disabilities from minority backgrounds  

E-Print Network (OSTI)

MENTAL RETARDATION VOLUME 42, NUMBER 6: 459–470 DECEMBER 2004 459qAmerican Association on Mental Retardation Access to Health Care for Individuals With Developmental Disabilities From Minority Backgrounds Amanda Reichard, Therese Marie Sacco, and H.... Rutherford Turnbull, III Abstract In this project we examined access to health care by individuals with developmental disabilities in Kansas from low-income populations and from minority backgrounds. Four criteria for deter- mining access were employed...

Reichard, Amanda; Sacco, T. M.; Turnbull, H. Rutherford

2011-12-27T23:59:59.000Z

311

Modeling Lost-Particle Backgrounds in PEP-II Using LPTURTLE  

SciTech Connect

Background studies during the design, construction, commissioning, operation and improvement of BaBar and PEP-II have been greatly influenced by results from a program referred to as LPTURTLE (Lost Particle TURTLE) which was originally conceived for the purpose of studying gas background for SLC. This venerable program is still in use today. We describe its use, capabilities and improvements and refer to current results now being applied to BaBar.

Fieguth, T.; /SLAC; Barlow, R.; /Manchester U.; Kozanecki, W.; /DAPNIA, Saclay

2005-05-17T23:59:59.000Z

312

Solar neutrino-electron scattering as background limitation for double beta decay  

E-Print Network (OSTI)

The background on double beta decay searches due to elastic electron scattering of solar neutrinos of all double beta emitters with Q-value larger than 2 MeV is calculated, taking into account survival probability and flux uncertainties of solar neutrinos. This work determines the background level to be [1-2]E-7 counts /keV/kg/yr, depending on the precise Q-value of the double beta emitter. It is also shown that the background level increases dramatically if going to lower Q-values. Furthermore, studies are done for various detector systems under consideration for next generation experiments. It was found that experiments based on loaded liquid scintillator have to expect a higher background. Within the given nuclear matrix element uncertainties any approach exploring the normal hierarchy has to face this irreducible background, which is a limitation on the minimal achievable background for purely calorimetric approaches. Large scale liquid scintillator experiments might encounter this problem already while exploring the inverted hierarchy. Potential caveats by using more sophisticated experimental setups are also discussed.

N. F. de Barros; K. Zuber

2011-09-16T23:59:59.000Z

313

Systematic Fast Neutron Background Measurement Fluctuations in an Urban Area Using a Mobile Detection System  

SciTech Connect

Neutron background measurements using a mobile trailer-based system were conducted in Knoxville, Tennessee. The 0.5 m2 system consisting of 8 EJ-301 liquid scintillation detectors was used to collect neutron background measurements in order to better understand the systematic background variations that depend solely on the street-level measurement position in a local, downtown area. Data was collected along 5 different streets in the downtown Knoxville area, and the measurements were found to be repeatable. Using 10 min measurements, fractional uncertainty in each measured data point was <2%. Compared with fast neutron background count rates measured away from downtown Knoxville, a reduction in background count rates ranging from 10-50% was observed in the downtown area, sometimes varying substantially over distances of tens of meters. These reductions are attributed to the shielding of adjacent buildings, quantified in part here by the metric angle-of-open-sky. The adjacent buildings may serve to shield cosmic ray neutron flux.

Iyengar, Anagha S [ORNL; Beach, Matthew R [ORNL; Newby, Jason [ORNL; Fabris, Lorenzo [ORNL; Heilbronn, Lawrence [University of Tennessee, Knoxville (UTK); Hayward, J P [University of Tennessee, Knoxville (UTK)

2014-01-01T23:59:59.000Z

314

Dissecting the Gamma-Ray Background in Search of Dark Matter  

E-Print Network (OSTI)

Several classes of astrophysical sources contribute to the approximately isotropic gamma-ray background measured by the Fermi Gamma-Ray Space Telescope. In this paper, we use Fermi's catalog of gamma-ray sources (along with corresponding source catalogs at infrared and radio wavelengths) to build and constrain a model for the contributions to the extragalactic gamma-ray background from astrophysical sources, including radio galaxies, star-forming galaxies, and blazars. We then combine our model with Fermi's measurement of the gamma-ray background to derive constraints on the dark matter annihilation cross section, including contributions from both extragalactic and galactic halos and subhalos. The resulting constraints are competitive with the strongest current constraints from the Galactic Center and dwarf spheroidal galaxies. As Fermi continues to measure the gamma-ray emission from a greater number of astrophysical sources, it will become possible to more tightly constrain the astrophysical contributions to the extragalactic gamma-ray background. We project that with 10 years of data, Fermi's measurement of this background combined with the improved constraints on the astrophysical source contributions will yield a sensitivity to dark matter annihilations that exceeds the strongest current constraints by a factor of ~ 5 - 10.

Ilias Cholis; Dan Hooper; Samuel D. McDermott

2013-12-02T23:59:59.000Z

315

Measurement of Neutron Background at the Pyhasalmi mine for CUPP Project, Finland  

E-Print Network (OSTI)

A natural neutron flux is one of significant kind of background in high-sensitive underground experiments. Therefore, when scheduling a delicate underground measurements one needs to measure neutron background. Deep underground the most significant source of neutrons are the U-Th natural radioactive chains giving a fission spectrum with the temperature of 2-3 MeV. Another source is the U-Th alpha-reactions on light nuclei of mine rock giving neutrons with different spectra in the 1-15 MeV energy region. Normal basalt mine rocks contain 1 ppm g/g of U-238 and less. Deep underground those rocks produce natural neutron fluxes of 10^{-7} - 10^{-6} cm^{-2}s^{-1} above 1 MeV. To measure such a background one needs a special techniques. In the Institute for Nuclear Research, Moscow, the neutron spectrometer was developed and built which is sensitive to such a low neutron fluxes. At the end of 2001 the collection of neutron data at the Pyhasalmi mine was started for the CUPP project. During 2002 the background and rough energy spectra of neutron at underground levels 410, 660, 990 and 1410 m were measured. The result of the measurement of the neutron background at different levels of the Pyhasalmi mine is presented and discussed. Data analysis is performed in different energy ranges from thermal neutrons up to 25 MeV and above.

J. N. Abdurashitov; V. N. Gavrin; V. L. Matushko; A. A. Shikhin; V. E. Yants; J. Peltoniemi; T. Keranen

2006-07-20T23:59:59.000Z

316

Design of a novel Cherenkov detectors system for machine induced background monitoring in the CMS cavern  

E-Print Network (OSTI)

A novel detector system has been designed for an efficient online measurement of the machineinduced background in the CMS experimental cavern. The suppression of the CMS cavern background originating from pp collision products and the 25 ns bunch spacing have set the requirements for the detector design. Each detector unit will be a radiation hard, cylindrical Cherenkov radiator optically coupled to an ultra-fast UV-sensitive photomultiplier tube, providing a prompt, directionally sensitive measurement. Simulation and test beam measurements have shown the achievability of the goals that have driven the baseline design. The system will consist of 20 azimuthally distributed detectors per end, installed at a radius of r ~ 180 cm and a distance 20.6 m away from the CMS interaction region. The detector units will enable a measurement of the transverse distribution of the bunchby- bunch machine induced background flux. This will provide important feedback from the CMS on the beam conditions during the LHC machine s...

Orfanelli, Styliani; Giunta, Marina; Stickland, David P; Ambrose, Mitchell J; Rusack, Roger; Finkel, Alexey

2013-01-01T23:59:59.000Z

317

Conservation Laws and Stress-energy-momentum Tensors for Systems with Background Fields  

E-Print Network (OSTI)

This article attempts to delineate the roles played by non-dynamical background structures and Killing symmetries in the construction of stress-energy-momentum tensors generated from a diffeomorphism invariant action density. An intrinsic coordinate independent approach puts into perspective a number of spurious arguments that have historically lead to the main contenders, viz the Belinfante-Rosenfeld stress-energy-momentum tensor derived from a Noether current and the Einstein-Hilbert stress-energy-momentum tensor derived in the context of Einstein's theory of general relativity. Emphasis is placed on the role played by non-dynamical background (phenomenological) structures that discriminate between properties of these tensors particularly in the context of electrodynamics in media. These tensors are used to construct conservation laws in the presence of Killing Lie-symmetric background fields.

Jonathan Gratus; Yuri N. Obukhov; Robin W. Tucker

2012-06-28T23:59:59.000Z

318

High redshift AGNs and HI reionisation: limits from the unresolved X-ray background  

E-Print Network (OSTI)

The rapidly declining population of bright quasars at z~3 appears to make an increasingly small contribution to the ionising background at the HI Lyman limit. It is then generally though that massive stars in (pre-)galactic systems may provide the additional ionising flux needed to complete HI reionisation by z>6. A galaxy dominated background, however, may require that the escape fraction of Lyman continuum radiation from high redshift galaxies is as high as 10%, a value somewhat at odds with (admittedly scarce) observational constraints. High escape fractions from dwarf galaxies have been advocated, or, alternatively, a so-far undetected (or barely detected) population of unobscured, high-redshift faint AGNs. Here we question the latter hypothesis, and show that such sources, to be consistent with the measured level of the unresolved X-ray background at z=0, can provide a fraction of the HII filling factor not larger than 13% by z=6. The fraction rises to 10%.

Haardt, Francesco

2015-01-01T23:59:59.000Z

319

THE NEAR-INFRARED BACKGROUND INTENSITY AND ANISOTROPIES DURING THE EPOCH OF REIONIZATION  

SciTech Connect

A fraction of the extragalactic near-infrared (near-IR) background light involves redshifted photons from the ultraviolet (UV) emission from galaxies present during reionization at redshifts above 6. The absolute intensity and the anisotropies of the near-IR background provide an observational probe of the first-light galaxies and their spatial distribution. We estimate the extragalactic background light intensity during reionization by accounting for the stellar and nebular emission from first-light galaxies. We require the UV photon density from these galaxies to generate a reionization history that is consistent with the optical depth to electron scattering from cosmic microwave background measurements. We also require the bright-end luminosity function (LF) of galaxies in our models to reproduce the measured Lyman-dropout LFs at redshifts of 6-8. The absolute intensity is about 0.1-0.4 nW m{sup -2} sr{sup -1} at the peak of its spectrum at {approx}1.1 {mu}m. We also discuss the anisotropy power spectrum of the near-IR background using a halo model to describe the galaxy distribution. We compare our predictions for the anisotropy power spectrum to existing measurements from deep near-IR imaging data from Spitzer/IRAC, Hubble/NICMOS, and AKARI. The predicted rms fluctuations at tens of arcminute angular scales are roughly an order of magnitude smaller than the existing measurements. While strong arguments have been made that the measured fluctuations do not have an origin involving faint low-redshift galaxies, we find that measurements in the literature are also incompatible with galaxies present during the era of reionization. The measured near-IR background anisotropies remain unexplained with an unknown origin.

Cooray, Asantha; Gong Yan; Smidt, Joseph [Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States); Santos, Mario G. [CENTRA, Instituto Superior Tecnico, Technical University of Lisbon, Lisboa 1049-001 (Portugal)

2012-09-01T23:59:59.000Z

320

Stabilization of the filamentation instability and the anisotropy of the background plasma  

SciTech Connect

The interaction of a relativistic electron beam with an anisotropic Maxwellian plasma is investigated, with a focus on the stabilization condition for the filamentation instability. It is found that this condition is very sensitive to the anisotropy degree of the background plasma so that the investigation of the beam instability may not be easily decoupled from the state of the background plasma in typical fusion conditions. Furthermore, regardless of the plasma isotropy, filamentation can no longer be suppressed when the beam density exceeds a threshold value that is determined.

Bret, A.; Deutsch, C. [ETSI Industriales, Universidad de Castilla-La Mancha, 13071 Ciudad Real (Spain); Laboratoire de Physique des Gaz et des Plasmas (CNRS-UMR 8578), Universite Paris XI, Batiment 210, 91405 Orsay cedex (France)

2006-02-15T23:59:59.000Z

Note: This page contains sample records for the topic "foreground background beaver" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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321

Searching for dust in the intracluster medium from reddening of background galaxies  

E-Print Network (OSTI)

We report a search for the presence of dust in the intra-cluster medium based on the study of statistical reddening of background galaxies. Armed with the Red Sequence Cluster survey data, from which we extracted (i) a catalog of 458 clusters with z_clust = 0.005 pm 0.008, and = 0.000 pm 0.008] were found for galaxies background to the clusters, compared to the references. Assuming a Galactic extinction law, we derive an average visual extinction of = 0.004 pm 0.010 towards the inner 1x R_200 of clusters.

Sebastien Muller; Szu-Ying Wu; Bau-Ching Hsieh; Rosa Gonzalez; Laurent Loinard; Howard Yee; Mike Gladders

2008-01-17T23:59:59.000Z

322

The impact of non-Planckian effects on radio cosmological backgrounds  

E-Print Network (OSTI)

Non-Planckian (NP) spectral modifications of the CMB radiation spectrum can be produced due to the existence of a non-zero value of the plasma frequency at the recombination epoch. We present here an analysis of NP effects on the radio cosmological background and we derive, for the first time, predictions of their amplitude on three different observables: the CMB spectrum, the Sunyaev-Zel'dovich (SZ) effect in cosmic structures, and the 21-cm background temperature brightness change. We find that NP effect can manifest in the CMB spectrum at $\

Colafrancesco, Sergio; Marchegiani, Paolo

2015-01-01T23:59:59.000Z

323

On the Ginsparg-Wilson Dirac operator in the monopole backgrounds on the fuzzy 2-sphere  

E-Print Network (OSTI)

In the previous papers, we studied the 't Hooft-Polyakov (TP) monopole configurations in the U(2) gauge theory on the fuzzy 2-sphere,and showed they have nonzero topological charge in the formalism based on the Ginsparg-Wilson (GW) relation. In this paper, we will show an index theorem in the TP monopole background, which is defined in the projected space, and provide a meaning of the projection operator. We further calculate the spectrum of the GW Dirac operator in the TP monopole backgrounds, and confirm the index theorem in these cases.

Aoki, H; Maeda, T; Aoki, Hajime; Iso, Satoshi; Maeda, Toshiharu

2006-01-01T23:59:59.000Z

324

The photonuclear neutron and gamma-ray backgrounds in the fast ignition experiment  

SciTech Connect

In the fast-ignition scheme, very hard x-rays (hereinafter referred to as {gamma}-rays) are generated by Bremsstrahlung radiation from fast electrons. Significant backgrounds were observed around the deuterium-deuterium fusion neutron signals in the experiment in 2010. In this paper the backgrounds were studied in detail, based on Monte Carlo simulations, and they were confirmed to be {gamma}-rays from the target, scattered {gamma}-rays from the experimental bay walls ({gamma}{sup Prime }-rays), and neutrons generated by ({gamma}, n) reactions in either the target vacuum chamber or the diagnostic instruments ({gamma}-n neutrons).

Arikawa, Y.; Nagai, T.; Hosoda, H.; Abe, Y.; Kojima, S.; Fujioka, S.; Sarukura, N.; Nakai, M.; Shiraga, H.; Azechi, H. [Institute of Laser Engineering, Osaka University, 2-6 Yamadaoka Suita (Japan); Ozaki, T. [National Institution Fusion Science, 322-6 Oroshi-cho, Toki-city, Gifu (Japan)

2012-10-15T23:59:59.000Z

325

Oscillating Strings and Non-Abelian T-dual Klebanov-Witten Background  

E-Print Network (OSTI)

We study oscillating string solutions in the Klebanov-Witten and its non-Abelian T-dual background dualised along an SU(2) isometry. We find the string energy as the function of oscillation number and angular momentum. We show that for a particular set of T-dual co-ordinates both the background have equal string states. We also study the string states where the strings are expanding and contracting in the T-dual co-ordinate direction. We expect the presence of the superconformal field theory dual operators whose anomalous dimensions depend on T-dual co-ordinate.

Pradhan, Pabitra M

2014-01-01T23:59:59.000Z

326

Oscillating Strings and Non-Abelian T-dual Klebanov-Witten Background  

E-Print Network (OSTI)

We study oscillating string solutions in the Klebanov-Witten and its non-Abelian T-dual background dualised along an SU(2) isometry. We find the string energy as the function of oscillation number and angular momentum. We show that for a particular set of T-dual co-ordinates both the background have equal string states. We also study the string states where the strings are expanding and contracting in the T-dual co-ordinate direction. We expect the presence of the superconformal field theory dual operators whose anomalous dimensions depend on T-dual co-ordinate.

Pabitra M. Pradhan

2014-06-09T23:59:59.000Z

327

Improved Upper Limits on the Stochastic Gravitational-Wave Background from 2009–2010 LIGO and Virgo Data  

E-Print Network (OSTI)

Gravitational waves from a variety of sources are predicted to superpose to create a stochastic background. This background is expected to contain unique information from throughout the history of the Universe that is ...

Aasi, J.

328

Upper limits on a stochastic gravitational-wave background using LIGO and Virgo interferometers at 600–1000 Hz  

E-Print Network (OSTI)

A stochastic background of gravitational waves is expected to arise from a superposition of many incoherent sources of gravitational waves, of either cosmological or astrophysical origin. This background is a target for ...

Barsotti, Lisa

329

Characterisation and mitigation of beam-induced backgrounds observed in the ATLAS detector during the 2011 proton-proton run  

E-Print Network (OSTI)

This paper presents a summary of beam-induced backgrounds observed in the ATLAS detector and discusses methods to tag and remove background contaminated events in data. Trigger-rate based monitoring of beam-related backgrounds is presented. The correlations of backgrounds with machine conditions, such as residual pressure in the beam-pipe, are discussed. Results from dedicated beam-background simulations are shown, and their qualitative agreement with data is evaluated. Data taken during the passage of unpaired, i.e. non-colliding, proton bunches is used to obtain background-enriched data samples. These are used to identify characteristic features of beam-induced backgrounds, which then are exploited to develop dedicated background tagging tools. These tools, based on observables in the Pixel detector, the muon spectrometer and the calorimeters, are described in detail and their efficiencies are evaluated. Finally an example of an application of these techniques to a monojet analysis is given, which demonstra...

Aad, Georges; Abbott, Brad; Abdallah, Jalal; Abdel Khalek, Samah; Abdelalim, Ahmed Ali; Abdinov, Ovsat; Aben, Rosemarie; Abi, Babak; Abolins, Maris; AbouZeid, Ossama; Abramowicz, Halina; Abreu, Henso; Acharya, Bobby Samir; Adamczyk, Leszek; Adams, David; Addy, Tetteh; Adelman, Jahred; Adomeit, Stefanie; Adragna, Paolo; Adye, Tim; Aefsky, Scott; Aguilar-Saavedra, Juan Antonio; Agustoni, Marco; Aharrouche, Mohamed; Ahlen, Steven; Ahles, Florian; Ahmad, Ashfaq; Ahsan, Mahsana; Aielli, Giulio; Akdogan, Taylan; Åkesson, Torsten Paul Ake; Akimoto, Ginga; Akimov, Andrei; Alam, Mohammad; Alam, Muhammad Aftab; Albert, Justin; Albrand, Solveig; Aleksa, Martin; Aleksandrov, Igor; Alessandria, Franco; Alexa, Calin; Alexander, Gideon; Alexandre, Gauthier; Alexopoulos, Theodoros; Alhroob, Muhammad; Aliev, Malik; Alimonti, Gianluca; Alison, John; Allbrooke, Benedict; Allport, Phillip; Allwood-Spiers, Sarah; Almond, John; Aloisio, Alberto; Alon, Raz; Alonso, Alejandro; Alonso, Francisco; Altheimer, Andrew David; Alvarez Gonzalez, Barbara; Alviggi, Mariagrazia; Amako, Katsuya; Amelung, Christoph; Ammosov, Vladimir; Amor Dos Santos, Susana Patricia; Amorim, Antonio; Amram, Nir; Anastopoulos, Christos; Ancu, Lucian Stefan; Andari, Nansi; Andeen, Timothy; Anders, Christoph Falk; Anders, Gabriel; Anderson, Kelby; Andreazza, Attilio; Andrei, George Victor; Andrieux, Marie-Laure; Anduaga, Xabier; Angelidakis, Stylianos; Anger, Philipp; Angerami, Aaron; Anghinolfi, Francis; Anisenkov, Alexey; Anjos, Nuno; Annovi, Alberto; Antonaki, Ariadni; Antonelli, Mario; Antonov, Alexey; Antos, Jaroslav; Anulli, Fabio; Aoki, Masato; Aoun, Sahar; Aperio Bella, Ludovica; Apolle, Rudi; Arabidze, Giorgi; Aracena, Ignacio; Arai, Yasuo; Arce, Ayana; Arfaoui, Samir; Arguin, Jean-Francois; Argyropoulos, Spyridon; Arik, Engin; Arik, Metin; Armbruster, Aaron James; Arnaez, Olivier; Arnal, Vanessa; Arnault, Christian; Artamonov, Andrei; Artoni, Giacomo; Arutinov, David; Asai, Shoji; Ask, Stefan; Åsman, Barbro; Asquith, Lily; Assamagan, Ketevi; Astbury, Alan; Atkinson, Markus; Aubert, Bernard; Auge, Etienne; Augsten, Kamil; Aurousseau, Mathieu; Avolio, Giuseppe; Avramidou, Rachel Maria; Axen, David; Azuelos, Georges; Azuma, Yuya; Baak, Max; Baccaglioni, Giuseppe; Bacci, Cesare; Bach, Andre; Bachacou, Henri; Bachas, Konstantinos; Backes, Moritz; Backhaus, Malte; Backus Mayes, John; Badescu, Elisabeta; Bagnaia, Paolo; Bahinipati, Seema; Bai, Yu; Bailey, David; Bain, Travis; Baines, John; Baker, Oliver Keith; Baker, Mark; Baker, Sarah; Balek, Petr; Banas, Elzbieta; Banerjee, Piyali; Banerjee, Swagato; Banfi, Danilo; Bangert, Andrea Michelle; Bansal, Vikas; Bansil, Hardeep Singh; Barak, Liron; Baranov, Sergei; Barbaro Galtieri, Angela; Barber, Tom; Barberio, Elisabetta Luigia; Barberis, Dario; Barbero, Marlon; Bardin, Dmitri; Barillari, Teresa; Barisonzi, Marcello; Barklow, Timothy; Barlow, Nick; Barnett, Bruce; Barnett, Michael; Baroncelli, Antonio; Barone, Gaetano; Barr, Alan; Barreiro, Fernando; Barreiro Guimarães da Costa, João; Barrillon, Pierre; Bartoldus, Rainer; Barton, Adam Edward; Bartsch, Valeria; Basye, Austin; Bates, Richard; Batkova, Lucia; Batley, Richard; Battaglia, Andreas; Battistin, Michele; Bauer, Florian; Bawa, Harinder Singh; Beale, Steven; Beau, Tristan; Beauchemin, Pierre-Hugues; Beccherle, Roberto; Bechtle, Philip; Beck, Hans Peter; Becker, Anne Kathrin; Becker, Sebastian; Beckingham, Matthew; Becks, Karl-Heinz; Beddall, Andrew; Beddall, Ayda; Bedikian, Sourpouhi; Bednyakov, Vadim; Bee, Christopher; Beemster, Lars; Begel, Michael; Behar Harpaz, Silvia; Behera, Prafulla; Beimforde, Michael; Belanger-Champagne, Camille; Bell, Paul; Bell, William; Bella, Gideon; Bellagamba, Lorenzo; Bellomo, Massimiliano; Belloni, Alberto; Beloborodova, Olga; Belotskiy, Konstantin; Beltramello, Olga; Benary, Odette; Benchekroun, Driss; Bendtz, Katarina; Benekos, Nektarios; Benhammou, Yan; Benhar Noccioli, Eleonora; Benitez Garcia, Jorge-Armando; Benjamin, Douglas; Benoit, Mathieu; Bensinger, James; Benslama, Kamal; Bentvelsen, Stan; Berge, David; Bergeaas Kuutmann, Elin; Berger, Nicolas; Berghaus, Frank; Berglund, Elina; Beringer, Jürg; Bernat, Pauline; Bernhard, Ralf; Bernius, Catrin; Berry, Tracey; Bertella, Claudia; Bertin, Antonio; Bertolucci, Federico; Besana, Maria Ilaria; Besjes, Geert-Jan; Besson, Nathalie; Bethke, Siegfried; Bhimji, Wahid; Bianchi, Riccardo-Maria; Bianchini, Louis; Bianco, Michele; Biebel, Otmar; Bieniek, Stephen Paul; Bierwagen, Katharina; Biesiada, Jed; Biglietti, Michela; Bilokon, Halina; Bindi, Marcello; Binet, Sebastien

2013-01-01T23:59:59.000Z

330

(n,n?[gamma]) reactions in 6?3?,?6?5?Cu and background in 0[nu] [beta] [beta] experiments  

E-Print Network (OSTI)

Measurements of (n, xn?[gamma]) reactions in Cu are important for understanding neutroninduced background for certain underground double beta decay experiments. Neutroninduced gammas are a contribution to background for ...

Perepelitsa, Dennis V

2008-01-01T23:59:59.000Z

331

Estimation of background radiation doses for the Peninsular Malaysia’s population by ESR dosimetry of tooth enamel  

Science Journals Connector (OSTI)

It is worth mentioning that the background dose is required in evaluating a tooth’s excess dose of radiation workers or individuals accidentally exposed to radiation, by subtracting the background level of a give...

Mohd Rodzi; Kassym Zhumadilov; Megu Ohtaki…

2011-08-01T23:59:59.000Z

332

Stochastic background from cosmic (super)strings: Popcorn-like and (Gaussian) continuous regimes  

Science Journals Connector (OSTI)

In the era of the next generation of gravitational wave experiments a stochastic background from cusps of cosmic (super)strings is expected to be probed and, if not detected, to be significantly constrained. A popcornlike background can be, for part of the parameter space, as pronounced as the (Gaussian) continuous contribution from unresolved sources that overlap in frequency and time. We study both contributions from unresolved cosmic string cusps over a range of frequencies relevant to ground based interferometers, such as the LIGO/Virgo second generation and Einstein Telescope third generation detectors, the space antenna LISA, and pulsar timing arrays. We compute the sensitivity (at the 2? level) in the parameter space for the LIGO/Virgo second generation detector, the Einstein Telescope detector, LISA, and pulsar timing arrays. We conclude that the popcorn regime is complementary to the continuous background. Its detection could therefore enhance confidence in a stochastic background detection and possibly help determine fundamental string parameters such as the string tension and the reconnection probability.

Tania Regimbau; Stefanos Giampanis; Xavier Siemens; Vuk Mandic

2012-03-01T23:59:59.000Z

333

BACKGROUND REPORTS FOR THE CALIFORNIA CARBON CAPTURE AND STORAGE REVIEW PANEL  

E-Print Network (OSTI)

BACKGROUND REPORTS FOR THE CALIFORNIA CARBON CAPTURE AND STORAGE REVIEW PANEL Prepared by the Technical Advisory Team in support of The California Carbon Capture and Storage Review Panel 12 Carbon Capture and Storage Review Panel Contents 1. Overview of the Carbon Capture and Storage Panel

334

Criminal Background Check Request Form revised 08/13/2013 #404 Page 1 of 2  

E-Print Network (OSTI)

: Recruitment & Workforce Planning MS 1255 jobpath@tamu.edu Fax (979) 847-8877 NEED HELP? Recruitment & Workforce Planning Phone (979) 845-5154 jobpath@tamu.edu #12;Criminal Background Check Request Form revised-google-email-account.html It is important you read, understand and comply with following information: Recruitment and Workforce Planning

Boas, Harold P.

335

Micro-Raman Spectroscopy of Algae: Composition Analysis and Fluorescence Background Behavior  

E-Print Network (OSTI)

analysis; biodiesel Introduction To date, analysis of algae composition is a multi-staged processARTICLE Micro-Raman Spectroscopy of Algae: Composition Analysis and Fluorescence Background performed using Stokes Raman scattering for compositional analysis of algae. Two algal species, Chlorella

336

1. BACKGROUND & OBJECTIVES For geological carbon sequestration, it is essential to  

E-Print Network (OSTI)

1. BACKGROUND & OBJECTIVES · For geological carbon sequestration, it is essential to understand Material Characterization for Intermediate-scale Testing to Develop Strategies for Geologic Sequestration to generate comprehensive data sets. Due to the nature of the CO2 geological sequestration where supercritical

337

Generalized methods and solvers for noise removal from piecewise constant signals. I. Background theory  

Science Journals Connector (OSTI)

...Background theory Max A. Little 1 2 * Nick S. Jones 1 3 * Author for correspondence...new solvers, that blend the relative merits of existing methods in useful ways...Physics Oxford United Kingdom Jones Nick S. Author 3088 3114 Proceedings...

2011-01-01T23:59:59.000Z

338

1 Background and Motivation Today, services based on web technology are a hot  

E-Print Network (OSTI)

1 Background and Motivation Today, services based on web technology are a hot topic and popularity of e-commerce is growing. The increasing role of web technology is particularly strong in business that the maturity level of web browsing performance is still low, or at least unstable. In current practise, popular

van der Mei, Rob

339

Universal macroscopic background formation in surface super-roughening and Doochul Kim2  

E-Print Network (OSTI)

Universal macroscopic background formation in surface super-roughening H.-W. Lee1 and Doochul Kim2 roughening exhibits scaling behaviors. For example, the growth of the global surface width w(L,t), when on the anomalous roughening. Numerical simulations demonstrated the occurrence of the anomalous roughening in some

Kim, Doochul

340

Background: Global Warming, 2009 1. Unequivocally, the climate is warming. Natural systems are affected.  

E-Print Network (OSTI)

Background: Global Warming, 2009 1. Unequivocally, the climate is warming. Natural systems are affected. 2. Very likely (>90% certainty), humans are causing most of the warming. 3. No single technology are very likely to impose net annual costs, which will increase over time as global temperatures increase

Minnesota, University of

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341

Stochastic Heating by ECR as a Novel Means of Background Reduction in the KATRIN Spectrometers  

E-Print Network (OSTI)

The primary objective of the KATRIN experiment is to probe the absolute neutrino mass scale with a sensitivity of 200 meV (90% C.L.) by precision spectroscopy of tritium beta-decay. To achieve this, a low background of the order of 10 mHz in the region of the tritium beta-decay endpoint is required. Measurements with an electrostatic retarding spectrometer have revealed that electrons, arising from nuclear decays in the volume of the spectrometer, are stored over long time periods and thereby act as a major source of background exceeding this limit. In this paper we present a novel active background reduction method based on stochastic heating of stored electrons by the well-known process of electron cyclotron resonance (ECR). A successful proof-of-principle of the ECR technique was demonstrated in test measurements at the KATRIN pre-spectrometer, yielding a large reduction of the background rate. In addition, we have carried out extensive Monte Carlo simulations to reveal the potential of the ECR technique t...

Mertens, S; Bornschein, L; Drexlin, G; Fränkle, F M; Furse, D; Glück, F; Görhardt, S; Krömer, O; Leiber, B; Schlösser, K; Thümmler, T; Wandkowsky, N; Wüstling, S

2012-01-01T23:59:59.000Z

342

Early Nervous Systems: Theoretical background and a preliminary model of neuronal processes  

E-Print Network (OSTI)

Early Nervous Systems: Theoretical background and a preliminary model of neuronal processes Ot de cells evolved to connect pre-existing sensors and effectors. This proposal was strongly influenced brain as Holland (2003) called it, without fast and specialized connections between specific sensors

van Elburg, Ronald A.J.

343

SMART OCEANS BC Media Backgrounder From sensors to decisions when seconds count  

E-Print Network (OSTI)

SMART OCEANS BC ­ Media Backgrounder From sensors to decisions ­ when seconds count Introduction Oceans 2.0 and high speed, real-time analytics to monitor the #12;hundreds of sensors. Funding for Smart to develop fast event detection and enable a mobile Oceans 2.0 for use in geographically remote sensor

Pedersen, Tom

344

Investigating the Performance of Solar Air Conditioning Motivation/Background Findings  

E-Print Network (OSTI)

Investigating the Performance of Solar Air Conditioning Motivation/Background Findings Two Building-thermal collectors We investigated 3 types of solar cooling technologies: · Air conditioning consumes 10% of all conditioning can reduce energy consumption, only if paired with a suitable system · Conventional office air

345

DESIGN OF A THERMOSIPHON FOR COOLING LOW-BACKGROUND HPGE ARRAYS  

SciTech Connect

ABSTRACT A two-phase nitrogen thermosiphon was developed for the new generation of low-background high-purity germanium (HPGe) arrays. The cooling system for these arrays has to be able to handle the heat load (>20 W) presented by a large detector mass while meeting stringent requirements necessary for low-background systems. The HPGe detector modules should operate as close to liquid nitrogen temperature (<80K) as possible to provide adequate operating conditions for a full range of HPGe impurity concentrations. In addition, exceptional temperature stability (<1 K) is needed to reduce electronic gain shifts due to changes in the front-end electronics operating temperature. In order to meet the background requirements of state-of-the-art systems these arrays are enclosed in passive lead and copper shielding up to 1 m thick. In this paper we present a cooling system for low-background experiments that complies with these stringent geometrical restrictions. Active cooling was integrated via a horizontal thermosiphon that can be fabricated using ultra-pure electroformed copper. It was charged with nitrogen to 434 kPa (63 PSIA) at 292 K, which provided a fill ratio of 10%. The results showed that the thermosiphon can effectively remove in excess of 25 W of heat load.

Aguayo Navarrete, Estanislao; Fast, James E.; Reid, Douglas J.

2012-11-26T23:59:59.000Z

346

Background and interpretation of the `Marine Trophic Index' as a measure of biodiversity  

E-Print Network (OSTI)

Background and interpretation of the `Marine Trophic Index' as a measure of biodiversity Daniel human impacts on marine biodiversity. 2. TROPHIC LEVEL: HISTORY AND DEFINITIONS Predation is one known as `fishing down marine food webs', and the publication of a critical rejoinder by Food

Pauly, Daniel

347

Review of Electricity and It is useful to recall the background of Maxwell's Equations. We consider  

E-Print Network (OSTI)

Chapter 2 Review of Electricity and Magnetism It is useful to recall the background of Maxwell to consider induced electric dipoles. In non-polar materials, in the linear regime, the average dipole moment polarizability. The electric polarization P =Np =oNMOL e E is the dipole moment per volume, N is the number

Palffy-Muhoray, Peter

348

Doses and risks from uranium are not increased significantly by interactions with natural background photon radiation  

Science Journals Connector (OSTI)

......retained in the skeleton is associated with mineral bone and is not incorporated into living...Pattison J. E. , Hugtenberg R. P., Green S. Enhancement of natural background gamma-radiation...R. , Khoury H. J., Viera J. W., Lime V. J. M. MAX06 and FAX06: update of......

R. J. Tanner; J. S. Eakins; J. T. M. Jansen; J. D. Harrison

2012-08-01T23:59:59.000Z

349

Background-aware Pedestrian/Vehicle Detection System for Driving Environments  

E-Print Network (OSTI)

Background-aware Pedestrian/Vehicle Detection System for Driving Environments Ji Hoon Joung, M. S to enhance the reliability of detection of objects in a driving envi- ronment (e.g. pedestrian and vehicle detections. Our approach considers that if we remove a certain region from an image taken from a vehicle

Ryoo, Michael S.

350

Adaptive Background Learning for Vehicle Detection and Spatio-Temporal Tracking  

E-Print Network (OSTI)

1 Adaptive Background Learning for Vehicle Detection and Spatio- Temporal Tracking Chengcui Zhang1 processing, can be applied to traffic video analysis to address queue detection, vehicle classification , Shu-Ching Chen1* , Mei-Ling Shyu2 , Srinivas Peeta3 1 Distributed Multimedia Information System

Chen, Shu-Ching

351

DC WRRC Report No. 103 Background Study of the Ground Water in  

E-Print Network (OSTI)

Leaching 51 5.0. FILLINGS 51 5.1 Background Infonnation 51 5.2 Special Research Needs 54 6.0. CONCLUSION. Area showing the General latitude and longitude. Figure 2. Fall line in the Middle Atlantic Region. Figure 3. Geologic section across the District of Columbia area, showing the succession and general

District of Columbia, University of the

352

c13s, 11/30/93 DECISION THEORY --HISTORICAL BACKGROUND  

E-Print Network (OSTI)

c13s, 11/30/93 CHAPTER 13 DECISION THEORY -- HISTORICAL BACKGROUND ``Your act was unwise,'' I will be supplied when we take up decision theory.'' However, in postponing the topic until now we have not deprived. Decision This situation arose as soon as we started applying probability theory to our first problem. When

Rodriguez, Carlos

353

c13s, 11/30/93 DECISION THEORY HISTORICAL BACKGROUND  

E-Print Network (OSTI)

c13s, 11/30/93 CHAPTER 13 DECISION THEORY ­ HISTORICAL BACKGROUND "Your act was unwise," I when we take up decision theory." However, in postponing the topic until now we have not deprived. Decision This situation arose as soon as we started applying probability theory to our first problem. When

Rodriguez, Carlos

354

The White Dwarf -- White Dwarf galactic background in the LISA data  

E-Print Network (OSTI)

LISA (Laser Interferometer Space Antenna) is a proposed space mission, which will use coherent laser beams exchanged between three remote spacecraft to detect and study low-frequency cosmic gravitational radiation. In the low-part of its frequency band, the LISA strain sensitivity will be dominated by the incoherent superposition of hundreds of millions of gravitational wave signals radiated by inspiraling white-dwarf binaries present in our own galaxy. In order to estimate the magnitude of the LISA response to this background, we have simulated a synthesized population that recently appeared in the literature. We find the amplitude of the galactic white-dwarf binary background in the LISA data to be modulated in time, reaching a minimum equal to about twice that of the LISA noise for a period of about two months around the time when the Sun-LISA direction is roughly oriented towards the Autumn equinox. Since the galactic white-dwarfs background will be observed by LISA not as a stationary but rather as a cyclostationary random process with a period of one year, we summarize the theory of cyclostationary random processes, present the corresponding generalized spectral method needed to characterize such process, and make a comparison between our analytic results and those obtained by applying our method to the simulated data. We find that, by measuring the generalized spectral components of the white-dwarf background, LISA will be able to infer properties of the distribution of the white-dwarfs binary systems present in our Galaxy.

Jeffrey A. Edlund; Massimo Tinto; Andrzej Krolak; Gijs Nelemans

2005-04-22T23:59:59.000Z

355

Alpha Backgrounds and Their Implications for Neutrinoless Double-Beta Decay Experiments Using HPGe Detectors  

E-Print Network (OSTI)

Alpha Backgrounds and Their Implications for Neutrinoless Double-Beta Decay Experiments Using HPGe and Their Implications for Neutrinoless Double-Beta Decay Experiments Using HPGe Detectors Robert A. Johnson Chair of the Supervisory Committee: Professor John F. Wilkerson Physics The observation of neutrinoless double-beta decay

Washington at Seattle, University of - Department of Physics, Electroweak Interaction Research Group

356

Evaluation of Ultra-Low Background Materials for Uranium and Thorium Using ICP-MS  

SciTech Connect

An increasing number of physics experiments require low background materials for their construction. The presence of Uranium and Thorium and their progeny in these materials present a variety of unwanted background sources for these experiments. The sensitivity of the experiments continues to drive the necessary levels of detection ever lower as well. This requirement for greater sensitivity has rendered direct radioassay impractical in many cases requiring large quantities of material, frequently many kilograms, and prolonged counting times, often months. Other assay techniques have been employed such as Neutron Activation Analysis but this requires access to expensive facilities and instrumentation and can be further complicated and delayed by the formation of unwanted radionuclides. Inductively Coupled Plasma Mass Spectrometry (ICP-MS) is a useful tool and recent advancements have increased the sensitivity particularly in the elemental high mass range of U and Th. Unlike direct radioassay, ICP-MS is a destructive technique since it requires the sample to be in liquid form which is aspirated into a high temperature plasma. But it benefits in that it usually requires a very small sample, typically about a gram. Here we will discuss how a variety of low background materials such as copper, polymers, and fused silica are made amenable to ICP-MS assay and how the arduous task of maintaining low backgrounds of U and Th is achieved.

Hoppe, Eric W.; Overman, Nicole R.; LaFerriere, Brian D.

2013-08-08T23:59:59.000Z

357

Alpha Backgrounds for HPGe Detectors in Neutrinoless Double-Beta Decay Experiments  

E-Print Network (OSTI)

The Majorana Experiment will use arrays of enriched HPGe detectors to search for the neutrinoless double-beta decay of 76Ge. Such a decay, if found, would show lepton-number violation and confirm the Majorana nature of the neutrino. Searches for such rare events are hindered by obscuring backgrounds which must be understood and mitigated as much as possible. A potentially important background contribution to this and other double-beta decay experiments could come from decays of alpha-emitting isotopes in the 232Th and 238U decay chains on or near the surfaces of the detectors. An alpha particle emitted external to an HPGe crystal can lose energy before entering the active region of the detector, either in some external-bulk material or within the dead region of the crystal. The measured energy of the event will only correspond to a partial amount of the total kinetic energy of the alpha and might obscure the signal from neutrinoless double-beta decay. A test stand was built and measurements were performed to quantitatively assess this background. We present results from these measurements and compare them to simulations using Geant4. These results are then used to measure the alpha backgrounds in an underground detector in situ. We also make estimates of surface contamination tolerances for double-beta decay experiments using solid-state detectors.

R. A. Johnson; T. H. Burritt; S. R. Elliott; V. M. Gehman; V. E. Guiseppe; J. F. Wilkerson

2011-12-30T23:59:59.000Z

358

Astroparticle Physics with a Customized Low-Background Broad Energy Germanium Detector  

E-Print Network (OSTI)

The MAJORANA Collaboration is building the MAJORANA DEMONSTRATOR, a 60 kg array of high purity germanium detectors housed in an ultra-low background shield at the Sanford Underground Laboratory in Lead, SD. The MAJORANA DEMONSTRATOR will search for neutrinoless double-beta decay of 76Ge while demonstrating the feasibility of a tonne-scale experiment. It may also carry out a dark matter search in the 1-10 GeV/c^2 mass range. We have found that customized Broad Energy Germanium (BEGe) detectors produced by Canberra have several desirable features for a neutrinoless double-beta decay experiment, including low electronic noise, excellent pulse shape analysis capabilities, and simple fabrication. We have deployed a customized BEGe, the MAJORANA Low-Background BEGe at Kimballton (MALBEK), in a low-background cryostat and shield at the Kimballton Underground Research Facility in Virginia. This paper will focus on the detector characteristics and measurements that can be performed with such a radiation detector in a low-background environment.

MAJORANA Collaboration; C. E. Aalseth; M. Amman; F. T. Avignone III; H. O. Back; A. S. Barabash; P. S. Barbeau; M. Bergevin; F. E. Bertrand; M. Boswell; V. Brudanin; W. Bugg; T. H. Burritt; M. Busch; G. Capps; Y-D. Chan; J. I. Collar; R. J. Cooper; R. Creswick; J. A. Detwiler; J. Diaz; P. J. Doe; Yu. Efremenko; V. Egorov; H. Ejiri; S. R. Elliott; J. Ely; J. Esterline; H. Farach; J. E. Fast; N. Fields; P. Finnerty; B. Fujikawa; E. Fuller; V. M. Gehman; G. K. Giovanetti; V. E. Guiseppe; K. Gusey; A. L. Hallin; G. C Harper; R. Hazama; R. Henning; A. Hime; E. W. Hoppe; T. W. Hossbach; M. A. Howe; R. A. Johnson; K. J. Keeter; M. Keillor; C. Keller; J. D. Kephart; M. F. Kidd; A. Knecht; O. Kochetov; S. I. Konovalov; R. T. Kouzes; L. Leviner; J. C. Loach; P. N. Luke; S. MacMullin; M. G. Marino; R. D. Martin; D. -M. Mei; H. S. Miley; M. L. Miller; L. Mizouni; A. W. Meyers; M. Nomachi; J. L. Orrell; D. Peterson; D. G. Phillips II; A. W. P. Poon; G. Prior; J. Qian; D. C. Radford; K. Rielage; R. G. H. Robertson; L. Rodriguez; K. P. Rykaczewski; H. Salazar; A. G. Schubert; T. Shima; M. Shirchenko; D. Steele; J. Strain; G. Swift; K. Thomas; V. Timkin; W. Tornow; T. D. Van Wechel; I. Vanyushin; R. L. Varner; K. Vetter; J. F. Wilkerson; B. A. Wolfe; W. Xiang; E. Yakushev; H. Yaver; A. R. Young; C. -H. Yu; V. Yumatov; C. Zhang; S. Zimmerman

2010-07-19T23:59:59.000Z

359

Cosmogenic Production as a Background in Searching for Rare Physics Processes  

E-Print Network (OSTI)

We revisit calculations of the cosmogenic production rates for several long-lived isotopes that are potential sources of background in searching for rare physics processes such as the detection of dark matter and neutrinoless double-beta decay. Using updated cosmic-ray neutron flux measurements, we use TALYS 1.0 to investigate the cosmogenic activation of stable isotopes of several detector targets and find that the cosmogenic isotopes produced inside the target materials and cryostat can result in large backgrounds for dark matter searches and neutrinoless double-beta decay. We use previously published low-background HPGe data to constrain the production of $^{3}H$ on the surface and the upper limit is consistent with our calculation. We note that cosmogenic production of several isotopes in various targets can generate potential backgrounds for dark matter detection and neutrinoless double-beta decay with a massive detector, thus great care should be taken to limit and/or deal with the cosmogenic activation of the targets.

D. -M. Mei; Z. -B. Yin; S. R. Elliott

2009-03-12T23:59:59.000Z

360

OIL SPILL BACKGROUND Marcia K McNutt, Juan Lasheras, 'Franklin Shaffer',  

E-Print Network (OSTI)

OIL SPILL BACKGROUND Marcia K McNutt, Juan Lasheras, 'Franklin Shaffer', BlIIlehr to: pmbommer on the fate and behavior of spilled oil. Of course, since this spill originates a mile deep, some. ~ Lehr book chapter .pdf #12;Review of modeling procedures for oil spill weathering behavior William J

Fleskes, Joe

Note: This page contains sample records for the topic "foreground background beaver" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

STATISTICS OF EXTREMES IN CLIMATOLOGY AND HYDROLOGY PART I: BACKGROUND AND TRADITIONAL APPROACHES  

E-Print Network (OSTI)

1 STATISTICS OF EXTREMES IN CLIMATOLOGY AND HYDROLOGY PART I: BACKGROUND AND TRADITIONAL APPROACHES;3 Outline (1) Historical Perspective (2) Basic Characteristics of Climate/Hydrologic Extremes (3) Traditional Statistical Analysis of Climate/Hydrologic Extremes (4) Spatial/Temporal Dependence of Climate

Katz, Richard

362

Background Model formulation Patch model SIK model Conclusions War of the Worlds: Modelling the spread of an  

E-Print Network (OSTI)

Background Model formulation Patch model SIK model Conclusions War of the Worlds: Modelling the spread of an invasive species an #12;Background Model formulation Patch model SIK model Conclusions Model formulation Patch model SIK model Conclusions Outline 1 Background 2 Model formulation Equations

Linder, Tamás

363

Background: Long-Term Daily and Monthly Climate Records from Stations  

NLE Websites -- All DOE Office Websites (Extended Search)

Background: Long-Term Daily and Monthly Climate Records from Stations Background: Long-Term Daily and Monthly Climate Records from Stations Across the Contiguous United States The United States Historical Climatology Network (USHCN) is a high-quality data set of daily and monthly records of basic meteorological variables from 1218 observing stations across the 48 contiguous United States. Daily data include observations of maximum and minimum temperature, precipitation amount, snowfall amount, and snow depth; monthly data consist of monthly-averaged maximum, minimum, and mean temperature and total monthly precipitation. Most of these stations are U.S. Cooperative Observing Network stations located generally in rural locations, while some are National Weather Service First-Order stations that are often located in more urbanized environments. The USHCN has been developed over the years at

364

Stochastic backgrounds in alternative theories of gravity: Overlap reduction functions for pulsar timing arrays  

Science Journals Connector (OSTI)

In the next decade gravitational waves might be detected using a pulsar timing array. In an effort to develop optimal detection strategies for stochastic backgrounds of gravitational waves in generic metric theories of gravity, we investigate the overlap reduction functions for these theories and discuss their features. We show that the sensitivity to nontransverse gravitational waves is greater than the sensitivity to transverse gravitational waves and discuss the physical origin of this effect. We calculate the overlap reduction functions for the current NANOGrav pulsar timing array and show that the sensitivity to the vector and scalar-longitudinal modes can increase dramatically for pulsar pairs with small angular separations. For example, the J1853+1303-J1857+0943 pulsar pair, with an angular separation of about 3°, is about 104 times more sensitive to the longitudinal component of the stochastic background, if it is present, than the transverse components.

Sydney J. Chamberlin and Xavier Siemens

2012-04-12T23:59:59.000Z

365

Optimal strategies for gravitational wave stochastic background searches in pulsar timing data  

Science Journals Connector (OSTI)

A low frequency stochastic background of gravitational waves may be detected by pulsar timing experiments in the next 5 to 10 yr. Using methods developed to analyze interferometric gravitational wave data, in this paper we lay out the optimal techniques to detect a background of gravitational waves using a pulsar timing array. We show that for pulsar distances and gravitational wave frequencies typical of pulsar timing experiments, neglecting the effect of the metric perturbation at the pulsar does not result in a significant deviation from optimality. We discuss methods for setting upper limits using the optimal statistic, show how to construct skymaps using the pulsar timing array, and consider several issues associated with realistic analysis of pulsar timing data.

Melissa Anholm; Stefan Ballmer; Jolien D. E. Creighton; Larry R. Price; Xavier Siemens

2009-04-21T23:59:59.000Z

366

Loop Variables and the Interacting Open String in a Curved Background  

E-Print Network (OSTI)

Applying the loop variable proposal to a sigma model (with boundary) in a curved target space, we give a systematic method for writing the gauge and generally covariant interacting equations of motion for the modes of the open string in a curved background. As in the free case described in an earlier paper, the equations are obtained by covariantizing the flat space (gauge invariant) interacting equations and then demanding gauge invariance in the curved background. The resulting equation has the form of a sum of terms that would individually be gauge invariant in flat space or at zero interaction strength, but mix amongst themselves in curved space when interactions are turned on. The new feature is that the loop variables are deformed so that there is a mixing of modes. Unlike the free case, the equations are coupled, and all the modes of the open string are required for gauge invariance.

B. Sathiapalan

2005-03-01T23:59:59.000Z

367

Inflation from D3-brane motion in the background of D5-branes  

Science Journals Connector (OSTI)

We study inflation arising from the motion of a Bogomol’nyi-Prasad-Sommerfield D3-brane in the background of a stack of k parallel D5-branes. There are two scalar fields in this setup: (i) the radion field R, a real scalar field, and (ii) a complex tachyonic scalar field ? living on the world volume of the open string stretched between the D3 and D5 branes. We find that inflation is realized by the potential of the radion field, which satisfies observational constraints coming from the cosmic microwave background. After the radion becomes of the order of the string length scale ls, the dynamics is governed by the potential of the complex scalar field. Since this field has a standard kinematic term, reheating can be successfully realized by the mechanism of tachyonic preheating with spontaneous symmetry breaking.

Sudhakar Panda; M. Sami; Shinji Tsujikawa; John Ward

2006-04-07T23:59:59.000Z

368

BPS D-branes from an unstable D-brane in a curved background  

Science Journals Connector (OSTI)

We find exact tachyon kink solutions of Dirac-Born-Infeld–type effective action describing an unstable D5-brane with a world volume gauge field turned on in a curved background. The background of interest is the ten-dimensional lift of the Salam-Sezgin vacuum and, in the asymptotic limit, it approaches R1,4×T2×S3. The solutions are identified as composites of lower-dimensional D-branes and fundamental strings, and, in the BPS limit, they become a D4D2F1 composite wrapped on R1,2×T2 where T2 is inside S3. In one class of solutions we find an infinite degeneracy with respect to a constant magnetic field along the direction of the Neveu-Schwarz–Neveu-Schwarz field on S3.

Chanju Kim; Yoonbai Kim; Hwang-hyun Kwon; O-Kab Kwon

2005-07-13T23:59:59.000Z

369

The new standard’s HVAC background noise requirements and their implementation in building design  

Science Journals Connector (OSTI)

The new ANSI classroom standard recommends long?term steady?state background sound level limits of 35 dBA and 55 dBC. Since the HVAC system is typically a room’s dominant steady?state noise source it is usually reasonable to apply these limits to the design of the system assuming that other noise sources produce insignificant additions to the room’s long?term background noise environment. The recommended sound level limits are significantly lower than current industry standards and complying with them will increase system costs. School administrators architects and HVAC system designers should therefore be prepared for the changes. This paper summarizes equipment selection and system design guidelines that have been found to be necessary for ensuring compliance with the sound level limits.

2001-01-01T23:59:59.000Z

370

Neutron Inelastic Scattering Processes as Background for Double-Beta Decay Experiments  

E-Print Network (OSTI)

We investigate several Pb$(n,n'\\gamma$) and Ge$(n,n'\\gamma$) reactions. We measure $\\gamma$-ray production from Pb$(n,n'\\gamma$) reactions that can be a significant background for double-beta decay experiments which use lead as a massive inner shield. Particularly worrisome for Ge-based double-beta decay experiments are the 2041-keV and 3062-keV $\\gamma$ rays produced via Pb$(n,n'\\gamma$). The former is very close to the ^{76}Ge double-beta decay endpoint energy and the latter has a double escape peak energy near the endpoint. Excitation $\\gamma$-ray lines from Ge$(n,n'\\gamma$) reactions are also observed. We consider the contribution of such backgrounds and their impact on the sensitivity of next-generation searches for neutrinoless double-beta decay using enriched germanium detectors.

D. -M. Mei; S. R. Elliott; A. Hime; V. Gehman; K. Kazkaz

2007-04-03T23:59:59.000Z

371

Background information for programs to improve the energy efficiency of Northwest residential rental property  

SciTech Connect

This report was prepared for the Office of Conservation, Bonneville Power Administration. The report will be used by the Office as background information to support future analysis and implementation of electricity conservation programs for owners of residential rental housing in the Northwest. The principal objective of the study was to review market research information relating to attitudes and actions of Northwest rental housing owners and, to a lesser extent, tenants toward energy conservation and energy-efficiency improvements. Available market research data on these subjects were found to be quite limited. The most useful data were two surveys of Seattle rental housing owners conducted in late 1984 for Seattle City Light. Several other surveys provided supplemental market research information in selected areas. In addition to market research information, the report also includes background information on rental housing characteristics in the Northwest.

Hendrickson, P.L.

1986-02-01T23:59:59.000Z

372

Ginsparg-Wilson Dirac operator in the monopole backgrounds on the fuzzy 2-sphere  

E-Print Network (OSTI)

In the previous papers, we studied the 't Hooft-Polyakov (TP) monopole configurations in the U(2) gauge theory on the fuzzy 2-sphere,and showed that they have nonzero topological charge in the formalism based on the Ginsparg-Wilson (GW) relation. In this paper, we will show an index theorem in the TP monopole background, which is defined in the projected space, and provide a meaning of the projection operator. We also extend the index theorem to general configurations which do not satisfy the equation of motion, and show that the configuration space can be classified into the topological sectors. We further calculate the spectrum of the GW Dirac operator in the TP monopole backgrounds, and consider the index theorem in these cases.

Hajime Aoki; Satoshi Iso; Toshiharu Maeda

2006-10-11T23:59:59.000Z

373

Ginsparg-Wilson Dirac operator in monopole backgrounds on the fuzzy 2-sphere  

Science Journals Connector (OSTI)

In previous papers, we studied ’t Hooft-Polyakov (TP) monopole configurations in U(2) gauge theory on the fuzzy 2-sphere, and showed that they have nonzero topological charges in the formalism based on the Ginsparg-Wilson (GW) relation. In this paper, we will show an index theorem in the TP monopole background, which is defined in the projected space, and provides meaning of the projection operator. We also extend the index theorem to general configurations which do not satisfy the equation of motion, and show that configuration space can be classified into topological sectors. We further calculate the spectrum of the GW Dirac operator in TP monopole backgrounds, and consider the index theorem in these cases.

Hajime Aoki; Satoshi Iso; Toshiharu Maeda

2007-04-27T23:59:59.000Z

374

Gamma-Ray Bursts, Ultra High Energy Cosmic Rays, and Cosmic Gamma-Ray Background  

E-Print Network (OSTI)

We argue that gamma-ray bursts (GRBs) may be the origin of the cosmic gamma-ray background radiation observed in GeV range. It has theoretically been discussed that protons may carry a much larger amount of energy than electrons in GRBs, and this large energy can be radiated in TeV range by synchrotron radiation of ultra-high-energy protons (\\sim 10^{20} eV). The possible detection of GRBs above 10 TeV suggested by the Tibet and HEGRA groups also supports this idea. If this is the case, most of TeV gamma-rays from GRBs are absorbed in intergalactic fields and eventually form GeV gamma-ray background, whose flux is in good agreement with the recent observation.

Tomonori Totani

1998-10-14T23:59:59.000Z

375

MaGe - a Geant4-based Monte Carlo framework for low-background experiments  

E-Print Network (OSTI)

A Monte Carlo framework, MaGe, has been developed based on the Geant4 simulation toolkit. Its purpose is to simulate physics processes in low-energy and low-background radiation detectors, specifically for the Majorana and Gerda $^{76}$Ge neutrinoless double-beta decay experiments. This jointly-developed tool is also used to verify the simulation of physics processes relevant to other low-background experiments in Geant4. The MaGe framework contains simulations of prototype experiments and test stands, and is easily extended to incorporate new geometries and configurations while still using the same verified physics processes, tunings, and code framework. This reduces duplication of efforts and improves the robustness of and confidence in the simulation output.

Yuen-Dat Chan; Jason A. Detwiler; Reyco Henning; Victor M. Gehman; Rob A. Johnson; David V. Jordan; Kareem Kazkaz; Markus Knapp; Kevin Kroninger; Daniel Lenz; Jing Liu; Xiang Liu; Michael G. Marino; Akbar Mokhtarani; Luciano Pandola; Alexis G. Schubert; Claudia Tomei

2008-02-06T23:59:59.000Z

376

Landau background gauge fixing and the IR properties of Yang-Mills Green functions  

Science Journals Connector (OSTI)

We analyze the complete algebraic structure of the background field method for Yang-Mills theory in the Landau gauge and show several structural simplifications within this approach. In particular, we present a new way to study the IR behavior of Green functions in the Landau gauge and show that there exists a unique Green function whose IR behavior controls the IR properties of the gluon and the ghost propagators.

Pietro A. Grassi; Tobias Hurth; Andrea Quadri

2004-11-16T23:59:59.000Z

377

Draft 04/05/09 A new high-background-rejection dark matter Ge cryogenic  

E-Print Network (OSTI)

Draft 04/05/09 A new high-background-rejection dark matter Ge cryogenic detector The EDELWEISS of a cryogenic germanium detector for dark matter search is presented, taking advantage of the coplanar grid in the EURECA project of a one-ton cryogenic detector mass. PACS numbers: 07.57.Kp; 07.85.Nc; 72.20.Jv; 95.35.+d

Boyer, Edmond

378

Alternative treaty monitoring approaches using ultra-low background measurement technology  

SciTech Connect

The International Monitoring System (IMS) of the Comprehensive Test Ban Treaty includes a network of stations and laboratories for collection and analysis of radioactive aerosols. Alternative approaches to IMS operations are considered as a method of enhancing treaty verification. Ultra-low background (ULB) detection promises the possibility of improvements to IMS minimum detectable activities (MDAs) well below the current approach, requiring MDAp30 mBq/m3 of air for 140Ba, or about 106 fissions per daily sample.

Miley, Harry S.; Aalseth, Craig E.; Bowyer, Ted W.; Fast, James E.; Hayes, James C.; Hoppe, Eric W.; Hossbach, Todd W.; Keillor, Martin E.; Kephart, Jeremy D.; McIntyre, Justin I.; Seifert, Allen

2009-05-01T23:59:59.000Z

379

Low Frequency Measurement of the Spectrum of the Cosmic Background Radiation  

DOE R&D Accomplishments (OSTI)

We have made measurements of the cosmic background radiation spectrum at 5 wavelengths (0.33, 0.9, 3, 6.3, and 12 cm) using radiometers with wavelength-scaled corrugated horn antennas having very low sidelobes. A single large-mouth (0.7 m diameter) liquid-helium-cooled absolute reference load was used for all five radiometers. The results of the observations are consistent with previous measurements and represent a significant improvement in accuracy.

Smoot, G. F.; De Amici, G.; Friedman, S. D.; Witebsky, C.; Mandolesi, N.; Partridge, R. B.; Sironi, G.; Danese, L.; De Zotti, G.

1983-06-00T23:59:59.000Z

380

A novel approach to background reduction in double beta decay experiments  

E-Print Network (OSTI)

Active background reduction in high resolution calorimeters is a promising approach to achieve ultimate sensitivity in neutrinoless double beta decay experiments. We propose Cerenkov emission from beta rays in bolometric crystals as a viable alternative to scintillation. This novel approach could broaden the range of materials of interest for calorimetric searches of the double beta decay. We discuss the optical properties of TeO$_2$ crystals, as a show case.

T. Tabarelli de Fatis

2009-08-02T23:59:59.000Z

Note: This page contains sample records for the topic "foreground background beaver" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Background in the context of land contaminated with naturally occurring radioactive material  

Science Journals Connector (OSTI)

The financial implications of choosing a particular threshold for clearance of radioactively contaminated land are substantial, particularly when one considers the volume of naturally occurring radioactive material (NORM) created each year by the production and combustion of fossil fuels and the exploitation of industrial minerals. Inevitably, a compromise needs to be reached between the level of environmental protection sought and the finite resources available for remediation. In the case of natural series radionuclides, any anthropogenic input is always superimposed on the inventory already present in the soil; this 'background' inventory is conventionally disregarded when assessing remediation targets. Unfortunately, the term is not well defined and the concept of 'background dose' is open to alternative interpretations. In this paper, we address the issue of natural background from a geochemical rather than from a solely radiological perspective, illustrating this with an example from the china clay industry. We propose a simple procedure for decision making based on activity concentrations of primordial radionuclides and their progeny. Subsequent calculations of dose need to take into account the mineralogical and chemical characteristics of the contamination, which in the case of NORM are invariably reflected in uranium series disequilibrium.

D Read; G D Read; M C Thorne

2013-01-01T23:59:59.000Z

382

Conditions for Debris-Background Ion Interactions and Collisionless Shock Wave Generation  

SciTech Connect

We use hybrid simulations and simple theoretical arguments to determine when debris ions streaming relative to background ions in a collisionless, magnetized plasma couple strongly enough to generate a magnetosonic shock wave. We consider three types of configurations: one-dimensional, the two-dimensional extension of the 1-D case, and a more complex 2-D geometry that contains some effects that would be found in a laser-produced, laboratory plasma. We show that the simulation results as well as previous Russian and LLNL results reduce to a simple condition (R{sub m}/{rho}{sub d} = equal mass radius/debris ion gyroradius {ge} 0.7) for the generation of a shock wave. Strong debris interaction with the background is characterized by the formation of a magnetic pulse that steepens and speeds up as it encounters the debris ions deflected by the magnetic field. The pulse further evolves into a shock. As the earlier work has indicated, the process also involves the generation of a transverse electric field perpendicular to the flow and the magnetic field that accelerates the background ions radially outward, which in turn causes the speedup of the pulse. With electric and magnetic field probes, the UCLA laser experiments should be able to detect these signatures of coupling as well as the generation of the shock wave.

Winske, Dan [Los Alamos National Laboratory; Cowee, Misa [Los Alamos National Laboratory

2012-07-10T23:59:59.000Z

383

Ship Effect Neutron Measurements And Impacts On Low-Background Experiments  

SciTech Connect

The primary particles entering the upper atmosphere as cosmic rays create showers in the atmosphere that include a broad spectrum of secondary neutrons, muons and protons. These cosmic-ray secondaries interact with materials at the surface of the Earth, yielding prompt backgrounds in radiation detection systems, as well as inducing long-lived activities through spallation events, dominated by the higher-energy neutron secondaries. For historical reasons, the multiple neutrons produced in spallation cascade events are referred to as “ship effect” neutrons. Quantifying the background from cosmic ray induced activities is important to low-background experiments, such as neutrino-less double beta decay. Since direct measurements of the effects of shielding on the cosmic-ray neutron spectrum are not available, Monte Carlo modeling is used to compute such effects. However, there are large uncertainties (orders of magnitude) in the possible cross-section libraries and the cosmic-ray neutron spectrum for the energy range needed in such calculations. The measurements reported here were initiated to validate results from Monte Carlo models through experimental measurements in order to provide some confidence in the model results. The results indicate that the models provide the correct trends of neutron production with increasing density, but there is substantial disagreement between the model and experimental results for the lower-density materials of Al, Fe and Cu.

Aguayo Navarrete, Estanislao; Kouzes, Richard T.; Siciliano, Edward R.

2013-10-01T23:59:59.000Z

384

DISS. ETH No. 18454 Full Body Modeling from Video Sequences  

E-Print Network (OSTI)

is fully used. The foreground/background subtraction algorithm is dependent on the base line of the multi camera setup. If there is a small baseline between neigh- bouring sensors we use disparity maps to define the foreground and background. In an all around network with a small number of cameras where automatic identifica

Giger, Christine

385

A New Robust Operator for Computer Vision: Application to Range and Intensity Images  

E-Print Network (OSTI)

because both the foreground and background project to the same sensor pixel, and in part because along on the robustness of reconstruction techniques. First, when there are many depth discontinuities, range sensors can in the foreground and one in the background, intermingling over large image regions. The data values from one

Bystroff, Chris

386

An Analysis of the Effects of Background Variables on Attitudes and Policy at the Bonneville Power Administration.  

E-Print Network (OSTI)

?? The question is asked whether or not background, education, and training of middle and upper level bureaucratic personnel affects policy outcomes. The Bonneville Power… (more)

Millam, Philip George

1973-01-01T23:59:59.000Z

387

CUORE crystal validation runs: results on radioactive contamination and extrapolation to CUORE background  

E-Print Network (OSTI)

The CUORE Crystal Validation Runs (CCVRs) have been carried out since the end of 2008 at the Gran Sasso National Laboratories, in order to test the performances and the radiopurity of the TeO$_2$ crystals produced at SICCAS (Shanghai Institute of Ceramics, Chinese Academy of Sciences) for the CUORE experiment. In this work the results of the first 5 validation runs are presented. Results have been obtained for bulk contaminations and surface contaminations from several nuclides. An extrapolation to the CUORE background has been performed.

Alessandria, F; Ardito, R; Arnaboldi, C; Avignone, F T; Balata, M; Bandac, I; Banks, T I; Bari, G; Beeman, J W; Bellini, F; Bersani, A; Biassoni, M; Bloxham, T; Brofferio, C; Bryant, A; Bucci, C; Cai, X Z; Canonica, L; Capelli, S; Carbone, L; Cardani, L; Carrettoni, M; Chott, N; Clemenza, M; Cosmelli, C; Cremonesi, O; Creswick, R J; Dafinei, I; Dally, A; De Biasi, A; Decowski, M P; Deninno, M M; de Waard, A; Di Domizio, S; Ejzak, L; Faccini, R; Fang, D Q; Farach, H; Ferri, E; Ferroni, F; Fiorini, E; Foggetta, L; Freedman, S; Frossati, G; Giachero, A; Gironi, L; Giuliani, A; Gorla, P; Gotti, C; Guardincerri, E; Gutierrez, T D; Haller, E E; Han, K; Heeger, K M; Huang, H Z; Ichimura, K; Kadel, R; Kazkaz, K; Keppel, G; Kogler, L; Kolomensky, Y G; Kraft, S; Lenz, D; Li, Y L; Liu, X; Longo, E; Ma, Y G; Maiano, C; Maier, G; Martinez, C; Martinez, M; Maruyama, R H; Moggi, N; Morganti, S; Newman, S; Nisi, S; Nones, C; Norman, E B; Nucciotti, A; Orio, F; Orlandi, D; Ouellet, J; Pallavicini, M; Palmieri, V; Pattavina, L; Pavan, M; Pedretti, M; Pessina, G; Pirro, S; Previtali, E; Rampazzo, V; Rimondi, F; Rosenfeld, C; Rusconi, C; Salvioni, C; Sangiorgio, S; Schaeffer, D; Scielzo, N D; Sisti, M; Smith, A R; Stivanello, F; Taffarello, L; Terenziani, G; Tian, W D; Tomei, C; Trentalange, S; Ventura, G; Vignati, M; Wang, B; Wang, H W; Whitten, C A; Wise, T; Woodcraft, A; Xu, N; Zanotti, L; Zarra, C; Zhu, B X; Zucchelli, S

2011-01-01T23:59:59.000Z

388

CUORE crystal validation runs: results on radioactive contamination and extrapolation to CUORE background  

E-Print Network (OSTI)

The CUORE Crystal Validation Runs (CCVRs) have been carried out since the end of 2008 at the Gran Sasso National Laboratories, in order to test the performances and the radiopurity of the TeO$_2$ crystals produced at SICCAS (Shanghai Institute of Ceramics, Chinese Academy of Sciences) for the CUORE experiment. In this work the results of the first 5 validation runs are presented. Results have been obtained for bulk contaminations and surface contaminations from several nuclides. An extrapolation to the CUORE background has been performed.

F. Alessandria; E. Andreotti; R. Ardito; C. Arnaboldi; F. T. Avignone III; M. Balata; I. Bandac; T. I. Banks; G. Bari; J. W. Beeman; F. Bellini; A. Bersani; M. Biassoni; T. Bloxham; C. Brofferio; A. Bryant; C. Bucci; X. Z. Cai; L. Canonica; S. Capelli; L. Carbone; L. Cardani; M. Carrettoni; N. Chott; M. Clemenza; C. Cosmelli; O. Cremonesi; R. J. Creswick; I. Dafinei; A. Dally; A. De Biasi; M. P. Decowski; M. M. Deninno; A. de Waard; S. Di Domizio; L. Ejzak; R. Faccini; D. Q. Fang; H. Farach; E. Ferri; F. Ferroni; E. Fiorini; L. Foggetta; S. Freedman; G. Frossati; A. Giachero; L. Gironi; A. Giuliani; P. Gorla; C. Gotti; E. Guardincerri; T. D. Gutierrez; E. E. Haller; K. Han; K. M. Heeger; H. Z. Huang; K. Ichimura; R. Kadel; K. Kazkaz; G. Keppel; L. Kogler; Y. G. Kolomensky; S. Kraft; D. Lenz; Y. L. Li; X. Liu; E. Longo; Y. G. Ma; C. Maiano; G. Maier; C. Martinez; M. Martinez; R. H. Maruyama; N. Moggi; S. Morganti; S. Newman; S. Nisi; C. Nones; E. B. Norman; A. Nucciotti; F. Orio; D. Orlandi; J. Ouellet; M. Pallavicini; V. Palmieri; L. Pattavina; M. Pavan; M. Pedretti; G. Pessina; S. Pirro; E. Previtali; V. Rampazzo; F. Rimondi; C. Rosenfeld; C. Rusconi; C. Salvioni; S. Sangiorgio; D. Schaeffer; N. D. Scielzo; M. Sisti; A. R. Smith; F. Stivanello; L. Taffarello; G. Terenziani; W. D. Tian; C. Tomei; S. Trentalange; G. Ventura; M. Vignati; B. Wang; H. W. Wang; C. A. Whitten Jr; T. Wise; A. Woodcraft; N. Xu; L. Zanotti; C. Zarra; B. X. Zhu; S. Zucchelli

2011-09-05T23:59:59.000Z

389

Background Information for the Nevada National Security Site Integrated Sampling Plan, Revision 0  

SciTech Connect

This document describes the process followed to develop the Nevada National Security Site (NNSS) Integrated Sampling Plan (referred to herein as the Plan). It provides the Plan’s purpose and objectives, and briefly describes the Underground Test Area (UGTA) Activity, including the conceptual model and regulatory requirements as they pertain to groundwater sampling. Background information on other NNSS groundwater monitoring programs—the Routine Radiological Environmental Monitoring Plan (RREMP) and Community Environmental Monitoring Program (CEMP)—and their integration with the Plan are presented. Descriptions of the evaluations, comments, and responses of two Sampling Plan topical committees are also included.

Farnham, Irene; Marutzky, Sam

2014-12-01T23:59:59.000Z

390

Background field method: Alternative way of deriving the pinch technique’s results  

Science Journals Connector (OSTI)

We show that the background field method (BFM) is a simple way of deriving the same gauge-invariant results which are obtained by the pinch technique (PT). For illustration we construct gauge-invariant self-energy and three-point vertices for gluons at the one-loop level by the BFM and demonstrate that we get the same results which were derived via the PT. We also calculate the four-gluon vertex in the BFM and show that this vertex obeys the same Ward identity that was found with the PT.

Shoji Hashimoto; Jiro Kodaira; Yoshiaki Yasui; Ken Sasaki

1994-12-01T23:59:59.000Z

391

Early Standard Model Measurement and Determination of Standard Model Background for Searches  

E-Print Network (OSTI)

The Large Hadron Collider (LHC) at CERN in Geneva (Switzerland) will go in operation in the coming months and will soon enable us to analyze the highest energy collisions ever produced at an accelerator. Beyond Standard Model searches at LHC require a detailed understanding of the detector performance, reconstruction algorithms and triggering. Precision measurements of Standard Model processes are also mandatory to acquire the necessary knowledge of Standard Model background. Both ATLAS and CMS efforts are hence addressed to determine the best calibration candles and to design a realistic plan for the initial period of data taking.

S. Beauceron

2008-08-27T23:59:59.000Z

392

The Cosmic MeV Neutrino Background as a Laboratory for Black Hole Formation  

E-Print Network (OSTI)

Calculations of the cosmic rate of core collapses, and the associated neutrino flux, commonly assume that a fixed fraction of massive stars collapse to black holes. We argue that recent results suggest that this fraction instead increases with redshift. With relatively more stars vanishing as "unnovae" in the distant universe, the detectability of the cosmic MeV neutrino background is improved due to their hotter neutrino spectrum, and expectations for supernova surveys are reduced. We conclude that neutrino detectors, after the flux from normal SNe is isolated via either improved modeling or the next Galactic SN, can probe the conditions and history of black hole formation.

Hasan Yuksel; Matthew D. Kistler

2014-10-01T23:59:59.000Z

393

A new high-background-rejection dark matter Ge cryogenic detector  

E-Print Network (OSTI)

A new design of a cryogenic germanium detector for dark matter search is presented, taking advantage of the coplanar grid technique of event localisation for improved background discrimination. Experiments performed with prototype devices in the EDELWEISS II setup at the Modane underground facility demonstrate the remarkably high efficiency of these devices for the rejection of low-energy $\\beta$, approaching 10$^5$ . This opens the road to investigate the range beyond 10$^{-8}$ pb in the WIMP-nucleon collision cross-sections, as proposed in the EURECA project of a one-ton cryogenic detector mass.

Broniatowski, A; Armengaud, E; Bergé, L; Benoît, A; Besida, O; Blumer, J; Chantelauze, A; Chapellier, M; Chardin, G; Charlieux, F; Collin, S; Crauste, O; De Jésus, M; Di Stefano, P; Dolgorouki, Y; Domange, J; Dumoulin, L; Eitel, K; Gascon, J; Gerbier, G; Gros, M; Hannawald, M; Hervé, S; Juillard, A; Kluck, H; Kozlov, V; Lemrani, R; Lubashevskiy, A; Marrache, C; Marnieros, S; Navick, X -F; Nones, C; Olivieri, E; Pari, P; Paul, B; Rozov, S; Sanglard, V; Scorza, S; Semikh, S; Verdier, M -A; Vagneron, L; Yakushev, E

2009-01-01T23:59:59.000Z

394

Dynamical Generation of Spacetime Signature by Massive Quantum Fields on a Topologically Non-Trivial Background  

E-Print Network (OSTI)

The effective potential for a dynamical Wick field (dynamical signature) induced by the quantum effects of massive fields on a topologically non-trivial $D$ dimensional background is considered. It is shown that when the radius of the compactified dimension is very small compared with $\\Lambda^{1/2}$ (where $\\Lambda$ is a proper-time cutoff), a flat metric with Lorentzian signature is preferred on ${\\bf R}^4 \\times {\\bf S}^1$. When the compactification radius becomes larger a careful analysis of the 1-loop effective potential indicates that a Lorentzian signature is preferred in both $D=6$ and $D=4$ and that these results are relatively stable under metrical perturbations.

Sergei D. Odintsov; August Romeo; Robin W. Tucker

1994-06-22T23:59:59.000Z

395

Model-Independent Test for Scale-Dependent Non-Gaussianities in the Cosmic Microwave Background  

Science Journals Connector (OSTI)

We present a model-independent method to test for scale-dependent non-Gaussianities in combination with scaling indices as test statistics. Therefore, surrogate data sets are generated, in which the power spectrum of the original data is preserved, while the higher order correlations are partly randomized by applying a scale-dependent shuffling procedure to the Fourier phases. We apply this method to the Wilkinson Microwave Anisotropy Probe data of the cosmic microwave background and find signatures for non-Gaussianities on large scales. Further tests are required to elucidate the origin of the detected anomalies.

C. Räth, G. E. Morfill, G. Rossmanith, A. J. Banday, and K. M. Górski

2009-03-31T23:59:59.000Z

396

On the background estimation by time slides in a network of gravitational wave detectors  

E-Print Network (OSTI)

Time shifting the outputs of Gravitational Wave detectors operating in coincidence is a convenient way to estimate the background in a search for short duration signals. However this procedure is limited as increasing indefinitely the number of time shifts does not provide better estimates. We show that the false alarm rate estimation error saturates with the number of time shifts. In particular, for detectors with very different trigger rates this error saturates at a large value. Explicit computations are done for 2 detectors, and for 3 detectors where the detection statistic relies on the logical ``OR'' of the coincidences of the 3 couples in the network.

Michal Was; Marie-Anne Bizouard; Violette Brisson; Fabien Cavalier; Michel Davier; Patrice Hello; Nicolas Leroy; Florent Robinet; Vavoulidis Miltiadis

2009-11-25T23:59:59.000Z

397

Investigations of 2? decay measured by low background HPGe spectrometer OBELIX  

SciTech Connect

A low background high sensitive HPGe spectrometer OBELIX was installed at the Modane Underground Laboratory (LSM, France, 4800 m w.e.). The detector was designed to measure a contamination of enriched isotopes and radio-impurities in construction materials, to investigate rare nuclear processes such as resonance neutrinoless double electron capture and two-neutrino double beta decay to excited states of daughter nuclei. Spectrometer sensitivity, contamination of NEMO-3 sources and results of 2?2?{sup ?} decay of {sup 100}Mo to the 0{sup +} (1130 keV) and 2{sup +} (540 keV) excited states as well as future plans for OBELIX detector are given.

Rukhadze, Ekaterina [Institute of Experimental and Applied Physics, CTU in Prague, Horska 3a/22, 128 00 Prague 2 (Czech Republic); Collaboration: OBELIX Collaboration; SuperNEMO Collaboration

2013-12-30T23:59:59.000Z

398

Hanford Waste Vitrification Plant technical background document for best available radionuclide control technology demonstration  

SciTech Connect

This report provides the background documentation to support applications for approval to construct and operate new radionuclide emission sources at the Hanford Waste Vitrification Plant (HWVP) near Richland, Washington. The HWVP is required to obtain permits under federal and state statutes for atmospheric discharges of radionuclides. Since these permits must be issued prior to construction of the facility, draft permit applications are being prepared, as well as documentation to support these permits. This report addresses the applicable requirements and demonstrates that the preferred design meets energy, environmental, and economic criteria for Best Available Radionuclide Control Technology (BARCT) at HWVP. 22 refs., 11 figs., 25 tabs.

Carpenter, A.B.; Skone, S.S.; Rodenhizer, D.G.; Marusich, M.V. (Ebasco Services, Inc., Bellevue, WA (USA))

1990-10-01T23:59:59.000Z

399

An Index for the Dirac Operator on D3 Brane withBackground Fluxes  

SciTech Connect

We study the problem of instanton generated superpotentials in Calabi-Yau orientifold compactifications directly in type IIB string theory. To this end, we derive the Dirac equation on a Euclidean D3 brane in the presence of background fluxes. We propose an index which governs whether the generation of a superpotential in the effective 4d theory by D3 brane instantons is possible. Applying the formalism to various classes of examples, including the K3 x T{sup 2}/Z{sub 2} orientifold, in the absence and presence of fluxes, we show that our results are consistent with conclusions attainable via duality from an M-theory analysis.

Bergshoeff, Eric; /Groningen U.; Kallosh, Renata; /Stanford U., Phys. Dept. /Kyoto U., Yukawa Inst., Kyoto; Kashani-Poor, Amir-Kian; /Stanford U., Phys. Dept. /SLAC; Sorokin, Dmitri; /INFN, Padua /Padua U.; Tomasiello, Alessandro; /Stanford U., Phys. Dept.

2005-08-03T23:59:59.000Z

400

Stochastic background of relic gravitons in a bouncing quantum cosmological model  

SciTech Connect

The spectrum and amplitude of the stochastic background of relic gravitons produced in a bouncing universe is calculated. The matter content of the model consists of dust and radiation fluids, and the bounce occurs due to quantum cosmological effects when the universe approaches the classical singularity in the contracting phase. The resulting amplitude is very small and it cannot be observed by any present and near future gravitational wave detector. Hence, as in the ekpyrotic model, any observation of these relic gravitons will rule out this type of quantum cosmological bouncing model.

Bessada, Dennis [UNIFESP, Universidade Federal de São Paulo, Laboratório de Física Teórica e Computação Científica, Rua São Nicolau, 210, 09913-030, Diadema, SP (Brazil); Pinto-Neto, Nelson; Siffert, Beatriz B. [ICRA — CBPF, Centro Brasileiro de Pesquisas Físicas, Rua Dr. Xavier Sigaud, 150, Urca, 22290-180, Rio de Janeiro (Brazil); Miranda, Oswaldo D., E-mail: dennis.bessada@unifesp.br, E-mail: beatriz@if.ufrj.br, E-mail: nelsonpn@cbpf.br, E-mail: oswaldo@das.inpe.br [INPE, Instituto Nacional de Pesquisas Espaciais, Av. dos Astronautas, 1758, 12227-010, São José dos Campos, SP (Brazil)

2012-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "foreground background beaver" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

A Polarization Sensitive Bolometric Detector for Observations of the Cosmic Microwave Background  

E-Print Network (OSTI)

We have developed a bolometric detector that is intrinsically sensitive to linear polarization which is optimized for making measurements of the polarization of the cosmic microwave background radiation. The receiver consists of a pair of co-located silicon nitride micromesh absorbers which couple anisotropically to linearly polarized radiation through a corrugated waveguide structure. This system allows simultaneous background limited measurements of the Stokes I and Q parameters over ~ 30% bandwidths at frequencies from ~ 60 to 600 GHz. Since both linear polarizations traverse identical optical paths from the sky to the point of detection, the susceptibility to systematic effects is minimized. The amount of uncorrelated noise between the two polarization senses is limited to the quantum limit of thermal and photon shot noise, while drifts in the relative responsivity to orthogonal polarizations are limited to the effect of non-uniformity in the thin film deposition of the leads and the intrinsic thermistor properties. Devices using NTD Ge thermistors have achieved NEPs of 2 x 10^{-17} W/sqrt{Hz} with a 1/f knee below 100 mHz at a base temperature of 270 mK. Numerical modelling of the structures has been used to optimize the bolometer geometry and coupling to optics. Comparisons of numerical results and experimental data are made. A description of how the quantities measured by the device can be interpreted in terms of the Stokes parameters is presented. The receiver developed for the Boomerang and Planck HFI focal planes is presented in detail.

W. C. Jones; R. S. Bhatia; J. J. Bock; A. E. Lange

2002-09-08T23:59:59.000Z

402

The Origin of the Extragalactic Gamma-Ray Background and Implications for Dark-Matter Annihilation  

E-Print Network (OSTI)

The origin of the extragalactic $\\gamma$-ray background (EGB) has been debated for some time. { The EGB comprises the $\\gamma$-ray emission from resolved and unresolved extragalactic sources, such as blazars, star-forming galaxies and radio galaxies, as well as radiation from truly diffuse processes.} This letter focuses on the blazar source class, the most numerous detected population, and presents an updated luminosity function and spectral energy distribution model consistent with the blazar observations performed by the {\\it Fermi} Large Area Telescope (LAT). We show that blazars account for 50$^{+12}_{-11}$\\,\\% of the EGB photons ($>$0.1\\,GeV), and that {\\it Fermi}-LAT has already resolved $\\sim$70\\,\\% of this contribution. Blazars, and in particular low-luminosity hard-spectrum nearby sources like BL Lacs, are responsible for most of the EGB emission above 100\\,GeV. We find that the extragalactic background light, which attenuates blazars' high-energy emission, is responsible for the high-energy cut-off...

Ajello, M; Sanchez-Conde, M; Zaharijas, G; Gustafsson, M; Cohen-Tanugi, J; Dermer, C D; Inoue, Y; Hartmann, D; Ackermann, M; Bechtol, K; Franckowiak, A; Reimer, A; Romani, R W; Strong, A W

2015-01-01T23:59:59.000Z

403

An array of low-background 3He proportional counters for theSudbury Neutrino Observatory  

SciTech Connect

An array of Neutral-Current Detectors (NCDs) has been builtin order to make a unique measurement of the total active ux of solarneutrinos in the Sudbury Neutrino Observatory (SNO). Data in the thirdphase of the SNO experiment were collected between November 2004 andNovember 2006, after the NCD array was added to improve theneutral-current sensitivity of the SNO detector. This array consisted of36 strings of proportional counters lled with a mixture of 3He and CF4gas capable of detecting the neutrons liberated by the neutrino-deuteronneutral current reaction in the D2O, and four strings lled with a mixtureof 4He and CF4 gas for background measurements. The proportional counterdiameter is 5 cm. The total deployed array length was 398 m. The SNO NCDarray is the lowest-radioactivity large array of proportional countersever produced. This article describes the design, construction,deployment, and characterization of the NCD array, discusses theelectronics and data acquisition system, and considers event signaturesand backgrounds.

Amsbaugh, J.F.; Anaya, J.M.; Banar, J.; Bowles, T.J.; Browne,M.C.; Bullard, T.V.; Burritt, T.H.; Cox-Mobrand, G.A.; Dai, X.; H.Deng,X.; Di Marco, M.; Doe, P.J.; Dragowsky, M.R.; Duba, C.A.; Duncan, F.A.; Earle, E.D.; Elliott, S.R.; Esch, E.-I.; Fergani, H.; Formaggio, J.A.; Fowler, M.M.; Franklin, J.E.; Geissbuehler, P.; Germani, J.V.; Goldschmidt, A.; Guillian, E.; Hallin, A.L.; Harper, G.; Harvey, P.J.; Hazama, R.; Heeger, K.M.; Heise, J.; Hime, A.; Howe, M.A.; Huang, M.; Kormos, L.L.; Kraus, C.; Krauss, C.B.; Law, J.; Lawson, I.T.; Lesko,K.T.; Loach, J.C.; Majerus, S.; Manor, J.; McGee, S.; Miknaitis, K.K.S.; Miller, G.G.; Morissette, B.; Myers, A.; Oblath, N.S.; O'Kee, H.M.; Ollerhead, R.W.; Peeters, S.J.M.; Poon, A.W.P.; Prior, G.; Reitzner,S.D.; Rielage, K.; Robertson, R.G.H.; Skensved, P.; Smith, A.R.; Smith,M.W.E.; Steiger, T.D.; Stonehill,L.C.; Thornewell, P.M.; Tolich, N.; VanDevender, B.A.; VanWechel, T.D.; Wall, B.L.; Tseung, H.W.C.; Wendland,J.; West, N.; Wilhelmy, J.B.; Wilkerson, J.F.; Wouters, J.M.

2007-02-01T23:59:59.000Z

404

ON THE EFFECT OF THE COSMIC MICROWAVE BACKGROUND IN HIGH-REDSHIFT (SUB-)MILLIMETER OBSERVATIONS  

SciTech Connect

Modern (sub-)millimeter interferometers enable the measurement of the cool gas and dust emission of high-redshift galaxies (z > 5). However, at these redshifts the cosmic microwave background (CMB) temperature is higher, approaching, and even exceeding, the temperature of cold dust and molecular gas observed in the local universe. In this paper, we discuss the impact of the warmer CMB on (sub-)millimeter observations of high-redshift galaxies. The CMB affects the observed (sub-)millimeter dust continuum and the line emission (e.g., carbon monoxide, CO) in two ways: (1) it provides an additional source of (both dust and gas) heating and (2) it is a non-negligible background against which the line and continuum emission are measured. We show that these two competing processes affect the way we interpret the dust and gas properties of high-redshift galaxies using spectral energy distribution models. We quantify these effects and provide correction factors to compute what fraction of the intrinsic dust (and line) emission can be detected against the CMB as a function of frequency, redshift, and temperature. We discuss implications on the derived properties of high-redshift galaxies from (sub-)millimeter data. Specifically, the inferred dust and molecular gas masses can be severely underestimated for cold systems if the impact of the CMB is not properly taken into account.

Da Cunha, Elisabete; Groves, Brent; Walter, Fabian; Decarli, Roberto; Rix, Hans-Walter [Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, D-69117 Heidelberg (Germany)] [Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, D-69117 Heidelberg (Germany); Weiss, Axel [Max-Planck-Institut fuer Radioastronomie, Auf dem Huegel 69, D-53121 Bonn (Germany)] [Max-Planck-Institut fuer Radioastronomie, Auf dem Huegel 69, D-53121 Bonn (Germany); Bertoldi, Frank [Argelander Institute for Astronomy, University of Bonn, Auf dem Huegel 71, D-53121 Bonn (Germany)] [Argelander Institute for Astronomy, University of Bonn, Auf dem Huegel 71, D-53121 Bonn (Germany); Carilli, Chris [National Radio Astronomy Observatory, Pete V. Domenici Array Science Center, P.O. Box O, Socorro, NM 87801 (United States)] [National Radio Astronomy Observatory, Pete V. Domenici Array Science Center, P.O. Box O, Socorro, NM 87801 (United States); Daddi, Emanuele; Sargent, Mark [Laboratoire AIM, CEA/DSM-CNRS-Universite Paris Diderot, Irfu/Service d'Astrophysique, CEA Saclay, Orme des Merisiers, F-91191 Gif-sur-Yvette Cedex (France)] [Laboratoire AIM, CEA/DSM-CNRS-Universite Paris Diderot, Irfu/Service d'Astrophysique, CEA Saclay, Orme des Merisiers, F-91191 Gif-sur-Yvette Cedex (France); Elbaz, David; Ivison, Rob [UK Astronomy Technology Centre, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ (United Kingdom)] [UK Astronomy Technology Centre, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ (United Kingdom); Maiolino, Roberto [Cavendish Laboratory, University of Cambridge, 19 J. J. Thomson Avenue, Cambridge, CB3 0HE (United Kingdom)] [Cavendish Laboratory, University of Cambridge, 19 J. J. Thomson Avenue, Cambridge, CB3 0HE (United Kingdom); Riechers, Dominik [Department of Astronomy, Cornell University, Ithaca, NY 14853 (United States)] [Department of Astronomy, Cornell University, Ithaca, NY 14853 (United States); Smail, Ian, E-mail: cunha@mpia.de [Institute for Computational Cosmology, Durham University, South Road, Durham DH1 3LE (United Kingdom)] [Institute for Computational Cosmology, Durham University, South Road, Durham DH1 3LE (United Kingdom)

2013-03-20T23:59:59.000Z

405

Reduction of Radioactive Backgrounds in Electroformed Copper for Ultra-Sensitive Radiation Detectors  

SciTech Connect

Abstract Ultra-pure construction materials are required for the next generation of neutrino physics, dark matter and environmental science applications. These new efforts require materials with purity levels at or below 1 uBq/kg 232Th and 238U. Yet radiometric analysis lacks sensitivity below ~10 uBq/kg for the U and Th decay chains. This limits both the selection of clean materials and the validation of purification processes. Copper is an important high-purity material for low-background experiments due to the ease with which it can be purified by electrochemical methods. Electroplating for purification into near-final shapes, known as electroforming, is one such method. Continued refinement of the copper electroforming process is underway, for the first time guided by an ICP-MS based assay method that can measure 232Th and 238U near the desired purity levels. An assay of electroformed copper at 10 uBq/kg for 232Th has been achieved and is described. The implications of electroformed copper at or better than this purity on next-generation low-background experiments are discussed.

Hoppe, Eric W.; Aalseth, Craig E.; Farmer, Orville T.; Hossbach, Todd W.; Liezers, Martin; Miley, Harry S.; Overman, Nicole R.; Reeves, James H.

2014-02-08T23:59:59.000Z

406

Multi-wavelength Emission from the Fermi Bubble I. Stochastic acceleration from Background Plasma  

E-Print Network (OSTI)

We analyse processes of electron acceleration in the Fermi Bubbles in order to define parameters and restrictions of the models, which are suggested for the origin of these giant radio and gamma-ray structures. In the case of leptonic origin of the nonthermal radiation from the Bubbles, these electrons should be produced somehow in-situ because of relatively short lifetime of high energy electrons, which lose their energy by synchrotron and inverse Compton processes. It has been suggested that electrons in Bubbles may be accelerated by shocks produced by tidal disruption of star accreting onto the central black hole or a process of re-acceleration of electrons ejected by supernova remnants. These processes will be investigated in subsequent papers. In this paper we focus to study in-situ stochastic (Fermi) acceleration by a hydromagnetic/supersonic turbulence, in which electrons can be directly accelerated from the background plasma. We showed that the acceleration from the background plasma is able to explai...

Cheng, K S; Dogiel, V A; Ko, C M

2014-01-01T23:59:59.000Z

407

State background-radiation levels: results of measurements taken during 1975-1979  

SciTech Connect

Background radiation levels across the United States have been measured by the Off-Site Pollutant Measurements Group of the Health and Safety Research Division at Oak Ridge National Laboratory (ORNL). These measurements have been conducted as part of the ORNL program of radiological surveillance at inactive uranium mills and sites formerly utilized during Manhattan Engineer District and early Atomic Energy Commission projects. The measurements included determination of /sup 226/Ra, /sup 232/Th, and /sup 238/U concentrations in surface soil samples and measurement of external gamma-ray exposure rates at 1 m above the ground surface at the location of soil sampling. This information is being utilized for comparative purposes to determine the extent of contamination present at the survey sites and surrounding off-site areas. The sampling program to date has provided background information at 356 locations in 33 states. External gamma-ray exposure rates were found to range from less than 1 to 34 ..mu..R/h, with an US average of 8.5 ..mu..R/h. The nationwide average concentrations of /sup 226/Ra, /sup 232/Th, and /sup 238/U in surface soil were determined to be 1.1, 0.98, and 1.0 pCi/g, respectively.

Myrick, T.E.; Berven, B.A.; Haywood, F.F.

1981-11-01T23:59:59.000Z

408

Woodcutting behavior in beavers (Castoridae, Rodentia): estimating ecological performance in a modern and a fossil taxon  

Science Journals Connector (OSTI)

...paleontological evidence: Paleobiology, 23. 482-490. Uhmeier, A., 1995, Some fundamental-aspects of wood chipping: TAPPI Journal, 78, 10. 79-86. Van Valkenburgh, B., 1994, Ecomorphological analysis of fossil vertebrates and their paleocommunities...

Natalia Rybczynski

409

Riboswitch-based sensor in low optical background Svetlana V. Harbaugh, Molly E. Davidson, Yaroslav G. Chushak*  

E-Print Network (OSTI)

Riboswitch-based sensor in low optical background Svetlana V. Harbaugh, Molly E. Davidson, Yaroslav in the presence of theophylline. However, the BFP-eGFP FRET pair posses significant optical background-4 These RNA-based sensors bind to a ligand and alter the gene expression of downstream genes. Riboswitches

410

Enhanced Self-Focusing of an Ion Beam Pulse Propagating through a Background Plasma along a Solenoidal Magnetic Field  

E-Print Network (OSTI)

Enhanced Self-Focusing of an Ion Beam Pulse Propagating through a Background Plasma along.58.Lq, 52.59.Ã?f Neutralization and focusing of charged particle beam pulses by a background plasma form plasma elec- trons. The effects of the enhanced self-focusing are of particular importance

Kaganovich, Igor

411

SEARCH F O R LINEAR POLARIZATION O F THE COSMIC BACKGROUND RADIATION  

NLE Websites -- All DOE Office Websites (Extended Search)

SEARCH F SEARCH F O R LINEAR POLARIZATION O F THE COSMIC BACKGROUND RADIATION P h i l M. Lubin and George F. Smoot Space Sciences L a b o r a t o r y and Lawrence Berkeley L a b o r a t o r y U n i v e r s i t y of C a l i f o r n i a Berkeley, C a l i f o r n i a 94720 Received ABSTRACT W e p r e s e n t p r e l i m i n a r y measurements of t h e l i n e a r p o l a r i z a t i o n of t h e cosmic microwave background ( 3 ° K blackbody) r a d i a t i o n . These ground-based measurements a r e made a t 9 mm wavelength. W e f i n d no e v i d e n c e f o r l i n e a r p o l a r i z a t i o n , and s e t a n upper l i m i t f o r a p o l a r i z e d component of 0.8 m°K with a 95% confidence l e v e l . T h i s i m p l i e s t h a t t h e p r e s e n t rate of e x p a n s i o n of t h e Universe i s i s o t r o p i c t o one p a r t i n 1 0 , assuming no r e - i o n i z a t i o n of t h e p r i m o r d i a l plasma a f t e r recombination. 6 The observed cosmic microwave background r

412

AES NewEnergy, Inc. Order No. EA-248 I. BACKGROUND  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

8 8 I. BACKGROUND Exports of electricity from the United States to a foreign country are regulated and require authorization under section 202(e) of the Federal Power Act (FPA) (16 U.S.C. §824a(e)). On July 13, 2001, AES NewEnergy, Inc. (AES NewEnergy) applied to the Office of Fossil Energy (FE) of the Department of Energy (DOE) for authorization to transmit electric energy to Canada as a power marketer. AES NewEnergy, a Delaware corporation and wholly- owned subsidiary of the AES Corporation, a public utility holding company, is a power marketer that does not own or control any electric generation or transmission facilities nor does it have any franchised service territory in the United States. AES NewEnergy proposes to purchase surplus electric energy from electric utilities and

413

Anadarko's Proposed Acquisition of Kerr-McGee and Western Gas Resources, June 23, 2006, Background  

Gasoline and Diesel Fuel Update (EIA)

Aspects of Anadarko's Acquisition of Kerr-McGee Aspects of Anadarko's Acquisition of Kerr-McGee Corp. and Western Gas Resources Background On June 23, 2006, the Wall Street Journal (WSJ) reported that Anadarko Petroleum Corp had agreed to acquire Kerr-McGee Corp. and Western Gas Resources Inc. for $21.1 billion of cash (see "Anadarko to Buy Kerr-McGee, Western Gas for $21.1 Billion" (June 23, 2006)). Anadarko also will assume $2.2 billion of debt from the two companies. Anadarko will pay $16.4 billion ($70.50 per share) and assume $1.6 billion of debt to acquire Kerr-McGee and pay $4.7 billion ($61 per share) and assume $600 million of debt to acquire Western Gas. Additional information is available on Anadarko's web site. According to the WSJ, Anadarko's president and chief executive officer Jim Hacket noted that the

414

Evidence-Based Background Material Underlying Guidance for Federal Agencies in Implementing Strategic Sustainability Performance Plans  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

3/107 3/107 Evidence-Based Background Material Underlying Guidance for Federal Agencies in Implementing Strategic Sustainability Performance Plans Implementing Sustainability: The Institutional-Behavioral Dimension Elizabeth L. Malone Tom Sanquist Amy K. Wolfe Rick Diamond Christopher Payne Jerry Dion January 2011 (Updated June 2013) Federal Energy Management Program U.S. Department of Energy DOCUMENT AVAILABILITY Reports produced after January 1, 1996, are generally available free via the U.S. Department of Energy (DOE) Information Bridge. Web site http://www.osti.gov/bridge Reports produced before January 1, 1996, may be purchased by members of the public from the following source. National Technical Information Service 5285 Port Royal Road

415

PSEG Energy Resources & Trade, LLC Order No. EA-250 I. BACKGROUND  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

PSEG Energy Resources & Trade, LLC PSEG Energy Resources & Trade, LLC Order No. EA-250 I. BACKGROUND Exports of electricity from the United States to a foreign country are regulated and require authorization under section 202(e) of the Federal Power Act (FPA) (16 U.S.C. §824a(e)). On September 14, 2001, PSEG Energy Resources & Trade, LLC (PSEG ER&T) applied to the Office of Fossil Energy (FE) of the Department of Energy (DOE) for authorization to transmit electric energy to Canada as a power marketer. The power to be exported by PSEG ER&T will be surplus to the needs of PSEG ER&T's native load and may be supplied by PSEG ER&T-owned generation or purchased from electric utilities and other suppliers within the United States. The energy to be exported would be

416

Determination of boron isotope ratios by Zeeman effect background correction-graphite furnace atomic absorption spectrometry  

Science Journals Connector (OSTI)

A new method for the determination of isotopic ratio of boron using Zeeman effect background correction-graphite furnace atomic absorption spectrometry with conventional atomizer and natural-boron hollow cathode source is described. The isotope-shift Zeeman effect at 208.9 nm is utilized for isotopic ratio determination. At a given concentration of total boron, the net absorbance decreases linearly with increasing 10B/11B ratio. The absorbances are recorded at the field strength of 1.0 T. The isotope ratios measured by the proposed method were in good agreement with the results obtained by inductively coupled plasma-quadruple mass spectrometry or thermal ionization mass spectrometry. The present method is fairly fast and less expensive compared to the above techniques and is quite suitable for plant environments.

S. Thangavel; S.V. Rao; K. Dash; J. Arunachalam

2006-01-01T23:59:59.000Z

417

Quenching methods for background reduction in luminescence-based probe-target binding assays  

DOE Patents (OSTI)

Background luminescence is reduced from a solution containing unbound luminescent probes, each having a first molecule that attaches to a target molecule and having an attached luminescent moiety, and luminescent probe/target adducts. Quenching capture reagent molecules are formed that are capable of forming an adduct with the unbound luminescent probes and having an attached quencher material effective to quench luminescence of the luminescent moiety. The quencher material of the capture reagent molecules is added to a solution of the luminescent probe/target adducts and binds in a proximity to the luminescent moiety of the unbound luminescent probes to quench luminescence from the luminescent moiety when the luminescent moiety is exposed to exciting illumination. The quencher capture reagent does not bind to probe molecules that are bound to target molecules and the probe/target adduct emission is not quenched.

Cai, Hong (Los Alamos, NM); Goodwin, Peter M (Los Alamos, NM); Keller, Richard A. (Los Alamos, NM); Nolan, Rhiannon L. (Santa Fe, NM)

2007-04-10T23:59:59.000Z

418

Historical Background on the Performance Assessment for the Waste Isolation Pilot Plant  

SciTech Connect

In 1979, six years after selecting the Delaware Basin as a potential disposal area, Congress authorized the U.S. Department of Energy to build the Waste Isolation Pilot Plant (WIPP) near Carlsbad, New Mexico, as a Research and development facility for the safe management storage, and disposal of waste contaminated with transuranic radioisotopes. In 1998, 19 years after authorization and after site selection, the U.S. Environmental Protection Agency (EPA) certified that the WIPP disposal system complied with its regulations. The EPA's decision was primarily based on the results from a performance. assessment conducted in 1996, which is summarized in this special issue of Reliability Engineering and System Safety. This performance assessment was the culmination of four preliminary performance assessments conducted between 1989 and 1992. This paper provides a historical setting and context for how the performance of the deep geologic repository at the WIPP was analyzed. Also included is background on political forces acting on the project.

RECHARD,ROBERT P.

1999-10-21T23:59:59.000Z

419

soft X-ray background as a supernova blast wave viewed from inside: solar abundance models  

SciTech Connect

A model of the soft X-ray background is presented in which the Sun is assumed to be inside an active supernova blast wave. The blast wave evolves in a preexisting cavity. The broad band surface brightnesses is explained by such a blast wave with an explosion energy of E sub approx. 5 x 10 to the 50th power ergs and radius 80 to 100 pc, using solar abundances. An approach to treating the problem of large anisotropies in the ambient medium is also explored, accommodating the observed anticorrelation between the soft X-ray surface brightness and the 21 cm column density. It is found that only for post shock temperatures below 10 6 K a shock propagating into a density enhancement will be dimmer than a similar shock in a lower density region.

Edgar, R.J.

1984-01-01T23:59:59.000Z

420

Variational Assimilation for Xenon Dynamical Forecasts in Neutronic using Advanced Background Error Covariance Matrix  

E-Print Network (OSTI)

Data assimilation method consists in combining all available pieces of information about a system to obtain optimal estimates of initial states. The different sources of information are weighted according to their accuracy by the means of error covariance matrices. Our purpose here is to evaluate the efficiency of variational data assimilation for the xenon induced oscillations forecasts in nuclear cores. In this paper we focus on the comparison between 3DVAR schemes with optimised background error covariance matrix B and a 4DVAR scheme. Tests were made in twin experiments using a simulation code which implements a mono-dimensional coupled model of xenon dynamics, thermal, and thermal-hydraulic processes. We enlighten the very good efficiency of the 4DVAR scheme as well as good results with the 3DVAR one using a careful multivariate modelling of B.

Ponçot, Angélique; Bouriquet, Bertrand; Erhard, Patrick; Gratton, Serge; Thual, Olivier

2013-01-01T23:59:59.000Z

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421

Variational assimilation for xenon dynamical forecasts in neutronic using advanced background error covariance matrix modelling  

Science Journals Connector (OSTI)

Abstract Data assimilation method consists in combining all available pieces of information about a system to obtain optimal estimates of initial states. The different sources of information are weighted according to their accuracy by the means of error covariance matrices. Our purpose here is to evaluate the efficiency of variational data assimilation for the xenon induced oscillations forecasts in nuclear cores. In this paper we focus on the comparison between 3DVAR schemes with optimised background error covariance matrix B and a 4DVAR scheme. Tests were made in twin experiments using a simulation code which implements a mono-dimensional coupled model of xenon dynamics, thermal, and thermal–hydraulic processes. We enlighten the very good efficiency of the 4DVAR scheme as well as good results with the 3DVAR one using a careful multivariate modelling of B.

Angélique Ponçot; Jean-Philippe Argaud; Bertrand Bouriquet; Patrick Erhard; Serge Gratton; Olivier Thual

2013-01-01T23:59:59.000Z

422

Observations of cosmic gamma ray sources and their contribution to the diffuse gamma ray background  

SciTech Connect

The objective is to study soft gamma ray emission in the 0.1 to 10 MeV energy band for selected active galactic nuclei and explore how much they contribute to the total diffuse gamma ray background. A series of imaging observations of extragalactic objects in the low energy gamma-ray region were carried out by the Coded Aperture Directional Gamma-ray Telescope (DGT). The DGT was successfully flown at stratospheric balloon altitudes, and observations were made of the Crab, NGC 1275, MKN 421, and NGC 4151. The measured Crab spectrum is consistent with a featureless power-law of the form. Significant emission was detected up to 500 keV from the Seyfert galaxy, NGC 4151. To increase the total sky exposure the extragalactic field images were analyzed, including the 3C 273 region, obtained by the DGT.

Bhattacharya, D.

1990-01-01T23:59:59.000Z

423

Operational background air pollution prediction over Slovenia by QualeAria modelling system - validation  

Science Journals Connector (OSTI)

Slovenia is a country of very complex terrain and many problems with air pollution in the valleys, canyons and basins, where industrial air pollution is combined with traffic and domestic heating air pollution, giving rise to problems for the health impact and the ecosystems directly or indirectly. Among indirect effects is also effect on solar radiation budget because of photochemical smog and especially particulate air pollution. To assess air pollutants over the country, a preliminary application of an experimental operational forecast system is presented here, with the aim of exploring its potentials and limitations in modelling the background air quality, and to focus the aspects where improvements are needed for a true operational use.

Marija Zlata Božnar; Primož Mlakar; Boštjan Grašič; Giuseppe Calori; Alessio D'Allura; Sandro Finardi

2014-01-01T23:59:59.000Z

424

Background Rejection in the DMTPC Dark Matter Search Using Charge Signals  

E-Print Network (OSTI)

The Dark Matter Time Projection Chamber (DMTPC) collaboration is developing low-pressure gas TPC detectors for measuring WIMP-nucleon interactions. Optical readout with CCD cameras allows for the detection for the daily modulation in the direction of the dark matter wind, while several charge readout channels allow for the measurement of additional recoil properties. In this article, we show that the addition of the charge readout analysis to the CCD allows us too obtain a statistics-limited 90% C.L. upper limit on the $e^-$ rejection factor of $5.6\\times10^{-6}$ for recoils with energies between 40 and 200 keV$_{\\mathrm{ee}}$. In addition, requiring coincidence between charge signals and light in the CCD reduces CCD-specific backgrounds by more than two orders of magnitude.

J. P. Lopez; S. Ahlen; J. Battat; T. Caldwell; M. Chernicoff; C. Deaconu; D. Dujmic; A. Dushkin; W. Fedus; P. Fisher; F. Golub; S. Henderson; A. Inglis; A. Kaboth; G. Kohse; L. Kirsch; R. Lanza; A. Lee; J. Monroe; H. Ouyang; T. Sahin; G. Sciolla; N. Skvorodnev; H. Tomita; H. Wellenstein; I. Wolfe; R. Yamamoto; H. Yegoryan

2011-09-15T23:59:59.000Z

425

Massive charged scalar field in the Kerr-Newman background II: Hawking radiation  

E-Print Network (OSTI)

We perform accurate calculations of the energy-, momentum-, and charge-emission rates of a charged scalar field in the background of the Kerr-Newman black hole at the range of parameters for which the effect is not negligibly small and, at the same time, the semiclassical regime is, at least marginally, valid. For black holes with charge below or not much higher than the charge accretion limit $Q \\sim \\mu M/e$ (where $e$ and $\\mu$ are the electron's mass and charge), the time between the consequent emitting of two charged particles is very large. For primordial black holes the transition between the increasing and decreasing of the ratio $Q/M$ occurs around the charge accretion limit. The rotation increases the intensity of radiation up to three orders, while the effect of the field's mass strongly suppresses the radiation.

R. A. Konoplya; A. Zhidenko

2014-04-03T23:59:59.000Z

426

BAYESIAN INFERENCE OF POLARIZED COSMIC MICROWAVE BACKGROUND POWER SPECTRA FROM INTERFEROMETRIC DATA  

SciTech Connect

Detection of B-mode polarization of the cosmic microwave background (CMB) radiation is one of the frontiers of observational cosmology. Because they are an order of magnitude fainter than E-modes, it is quite a challenge to detect B-modes. Having more manageable systematics, interferometers prove to have a substantial advantage over imagers in detecting such faint signals. Here, we present a method for Bayesian inference of power spectra and signal reconstruction from interferometric data of the CMB polarization signal by using the technique of Gibbs sampling. We demonstrate the validity of the method in the flat-sky approximation for a simulation of an interferometric observation on a finite patch with incomplete uv-plane coverage, a finite beam size, and a realistic noise model. With a computational complexity of O(n {sup 3/2}), n being the data size, Gibbs sampling provides an efficient method for analyzing upcoming cosmology observations.

Karakci, Ata; Korotkov, Andrei; Tucker, Gregory S. [Department of Physics, Brown University, 182 Hope Street, Providence, RI 02912 (United States); Sutter, P. M.; Wandelt, Benjamin D. [Department of Physics, 1110 W. Green Street, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States); Zhang, Le; Timbie, Peter [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Bunn, Emory F., E-mail: ata_karakci@brown.edu [Physics Department, University of Richmond, Richmond, VA 23173 (United States)

2013-01-15T23:59:59.000Z

427

THE COSMIC INFRARED BACKGROUND EXPERIMENT (CIBER): THE NARROW-BAND SPECTROMETER  

SciTech Connect

We have developed a near-infrared spectrometer designed to measure the absolute intensity of the solar 854.2 nm Ca II Fraunhofer line, scattered by interplanetary dust, in the zodiacal light (ZL) spectrum. Based on the known equivalent line width in the solar spectrum, this measurement can derive the zodiacal brightness, testing models of the ZL based on morphology that are used to determine the extragalactic background light in absolute photometry measurements. The spectrometer is based on a simple high-resolution tipped filter placed in front of a compact camera with wide-field refractive optics to provide the large optical throughput and high sensitivity required for rocket-borne observations. We discuss the instrument requirements for an accurate measurement of the absolute ZL brightness, the measured laboratory characterization, and the instrument performance in flight.

Korngut, P. M.; Bock, J. [Jet Propulsion Laboratory (JPL), National Aeronautics and Space Administration (NASA), Pasadena, CA 91109 (United States); Renbarger, T.; Keating, B. [Department of Physics, University of California, San Diego, San Diego, CA 92093 (United States); Arai, T.; Matsumoto, T.; Matsuura, S. [Department of Space Astronomy and Astrophysics, Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency (JAXA), Sagamihara, Kanagawa 252-5210 (Japan); Battle, J.; Hristov, V.; Lanz, A.; Levenson, L. R.; Mason, P. [Department of Physics, California Institute of Technology, Pasadena, CA 91125 (United States); Brown, S. W.; Lykke, K. R.; Smith, A. W. [Sensor Science Division, National Institute of Standards and Technology (NIST), Gaithersburg, MD 20899 (United States); Cooray, A. [Center for Cosmology, University of California, Irvine, Irvine, CA 92697 (United States); Kim, M. G. [Department of Physics and Astronomy, Seoul National University, Seoul 151-742 (Korea, Republic of); Lee, D. H.; Nam, U. W. [Korea Astronomy and Space Science Institute (KASI), Daejeon 305-348 (Korea, Republic of); Shultz, B., E-mail: pkorngut@caltech.edu [Materion Barr Precision Optics and Thin Film Coatings, Westford, MA 01886 (United States); and others

2013-08-15T23:59:59.000Z

428

Evidence-Based Background Material Underlying Guidance for Federal Agencies in Implementing Strategic Sustainability Performance Plans  

NLE Websites -- All DOE Office Websites (Extended Search)

3/107 3/107 Evidence-Based Background Material Underlying Guidance for Federal Agencies in Implementing Strategic Sustainability Performance Plans Implementing Sustainability: The Institutional-Behavioral Dimension Elizabeth L. Malone Tom Sanquist Amy K. Wolfe Rick Diamond Christopher Payne Jerry Dion January 2011 (Updated June 2013) Federal Energy Management Program U.S. Department of Energy DOCUMENT AVAILABILITY Reports produced after January 1, 1996, are generally available free via the U.S. Department of Energy (DOE) Information Bridge. Web site http://www.osti.gov/bridge Reports produced before January 1, 1996, may be purchased by members of the public from the following source. National Technical Information Service 5285 Port Royal Road

429

The Evolution of Swift/BAT blazars and the origin of the MeV background  

SciTech Connect

We use 3 years of data from the Swift/BAT survey to select a complete sample of X-ray blazars above 15 keV. This sample comprises 26 Flat-Spectrum Radio Quasars (FSRQs) and 12 BL Lac objects detected over a redshift range of 0.03 < z < 4.0. We use this sample to determine, for the first time in the 15-55 keV band, the evolution of blazars. We find that, contrary to the Seyfert-like AGNs detected by BAT, the population of blazars shows strong positive evolution. This evolution is comparable to the evolution of luminous optical QSOs and luminous X-ray selected AGNs. We also find evidence for an epoch-dependence of the evolution as determined previously for radio-quiet AGNs. We interpret both these findings as a strong link between accretion and jet activity. In our sample, the FSRQs evolve strongly, while our best-fit shows that BL Lacs might not evolve at all. The blazar population accounts for 10-20% (depending on the evolution of the BL Lacs) of the Cosmic X-ray background (CXB) in the 15-55 keV band. We find that FSRQs can explain the entire CXB emission for energies above 500 keV solving the mystery of the generation of the MeV background. The evolution of luminous FSRQs shows a peak in redshift (z{sub c} = 4.3 {+-} 0.5) which is larger than the one observed in QSOs and X-ray selected AGNs. We argue that FSRQs can be used as tracers of massive elliptical galaxies in the early Universe.

Ajello, M.; /SLAC /KIPAC, Menlo Park; Costamante, L.; /Stanford U., HEPL /KIPAC, Menlo Park; Sambruna, R.M.; Gehrels, N.; /NASA, Goddard; Chiang, J.; /SLAC /KIPAC, Menlo Park; Rau, A.; /Caltech; Escala, A.; /SLAC /KIPAC, Menlo Park /Cerro Calan Observ.; Greiner, J.; /Garching, Max Planck Inst., MPE; Tueller, J.; /NASA, Goddard; Wall, J.V.; /British Columbia U.; Mushotzky, R.F.; /NASA, Goddard

2009-10-17T23:59:59.000Z

430

The Cryogenic Dark Matter Search and Background Rejection with Event Position Information  

SciTech Connect

Evidence from observational cosmology and astrophysics indicates that about one third of the universe is matter, but that the known baryonic matter only contributes to the universe at 4%. A large fraction of the universe is cold and non-baryonic matter, which has important role in the universe structure formation and its evolution. The leading candidate for the non-baryonic dark matter is Weakly Interacting Massive Particles (WIMPs), which naturally occurs in the supersymmetry theory in particle physics. The Cryogenic Dark Matter Search (CDMS) experiment is searching for evidence of a WIMP interaction off an atomic nucleus in crystals of Ge and Si by measuring simultaneously the phonon energy and ionization energy of the interaction in the CDMS detectors. The WIMP interaction energy is from a few keV to tens of keV with a rate less than 0.1 events/kg/day. To reach the goal of WIMP detection, the CDMS experiment has been conducted in the Soudan mine with an active muon veto and multistage passive background shields. The CDMS detectors have a low energy threshold and background rejection capabilities based on ionization yield. However, betas from contamination and other radioactive sources produce surface interactions, which have low ionization yield, comparable to that of bulk nuclear interactions. The low-ionization surface electron recoils must be removed in the WIMP search data analysis. An emphasis of this thesis is on developing the method of the surface-interaction rejection using location information of the interactions, phonon energy distributions and phonon timing parameters. The result of the CDMS Soudan run118 92.3 live day WIMP search data analysis is presented, and represents the most sensitive search yet performed.

Wang, Gen-sheng; /Case Western Reserve U.

2005-01-01T23:59:59.000Z

431

Heavy sterile neutrinos, entropy and relativistic energy production, and the relic neutrino background  

E-Print Network (OSTI)

We explore the implications of the existence of heavy neutral fermions (i.e., sterile neutrinos) for the thermal history of the early universe. In particular, we consider sterile neutrinos with rest masses in the 100 MeV to 500 MeV range, with couplings to ordinary active neutrinos large enough to guarantee thermal and chemical equilibrium at epochs in the early universe with temperatures T > 1 GeV, but in a range to give decay lifetimes from seconds to minutes. Such neutrinos would decouple early, with relic densities comparable to those of photons, but decay out of equilibrium, with consequent prodigious entropy generation prior to, or during, Big Bang Nucleosynthesis (BBN). Most of the ranges of sterile neutrino rest mass and lifetime considered are at odds with Cosmic Microwave Background (CMB) limits on the relativistic particle contribution to energy density (e.g., as parameterized by N_eff). However, some sterile neutrino parameters can lead to an acceptable N_eff. These parameter ranges are accompanied by considerable dilution of the ordinary background relic neutrinos, possibly an adverse effect on BBN, but sometimes fall in a range which can explain measured neutrino masses in some particle physics models. A robust signature of these sterile neutrinos would be a measured N_eff not equal to 3 coupled with no cosmological signal for neutrino rest mass when the detection thresholds for these probes are below laboratory-established neutrino mass values, either as established by the atmospheric neutrino oscillation scale or direct measurements with, e.g., KATRIN or neutrino-less double beta decay experiments.

George M. Fuller; Chad T. Kishimoto; Alexander Kusenko

2011-10-28T23:59:59.000Z

432

Laboratory Studies of Lead Removal from Liquid Scintillator in Preparation for KamLAND's Low Background Phase  

SciTech Connect

The removal of Radon induced Lead from liquid scintillator was extensively studied in preparation for KamLAND's low background phase. This work presents the results from laboratory experiments performed at the University of Alabama and their implications for KamLAND and future low background experiments using carbon based liquid scintillator. It was observed that distillation was the most effective purification procedure and that one must consider a non-polar and non-ionic component of Lead in order to reach the levels of radio-purity required for these new class of ultra-low background experiments.

Keefer, Gregory [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

2011-04-27T23:59:59.000Z

433

Measurement of low radioactivity background in a high voltage cable by high resolution inductively coupled plasma mass spectrometry  

SciTech Connect

The measurement of naturally occurring low level radioactivity background in a high voltage (HV) cable by high resolution inductively coupled plasma mass spectrometry (HR ICP MS) is presented in this work. The measurements were performed at the Chemistry Service of the Gran Sasso National Laboratory. The contributions to the radioactive background coming from the different components of the heterogeneous material were separated. Based on the mass fraction of the cable, the whole contamination was calculated. The HR ICP MS results were cross-checked by gamma ray spectroscopy analysis that was performed at the low background facility STELLA (Sub Terranean Low Level Assay) of the LNGS underground lab using HPGe detectors.

Vacri, M. L. di; Nisi, S.; Balata, M. [Gran Sasso National Laboratory, Chemistry Service, SS 17bis km 18.910, 67100 Assergi (Aq) (Italy)] [Gran Sasso National Laboratory, Chemistry Service, SS 17bis km 18.910, 67100 Assergi (Aq) (Italy)

2013-08-08T23:59:59.000Z

434

Simulation of Monsoon Depressions Using WRF-VAR: Impact of Different Background Error Statistics and Lateral Boundary Conditions  

Science Journals Connector (OSTI)

In a variational data assimilation system, background error statistics (BES) spread the influence of the observations in space and filter analysis increments through dynamic balance or statistical relationships. In a data-sparse region such as the ...

A. Routray; S. C. Kar; P. Mali; K. Sowjanya

2014-10-01T23:59:59.000Z

435

Mean and Turbulent Flow Downstream of a Low-Intensity Fire: Influence of Canopy and Background Atmospheric Conditions  

Science Journals Connector (OSTI)

This study examines the sensitivity of mean and turbulent flow in the planetary boundary layer (PBL) and roughness sub-layer to a low-intensity fire and evaluates whether the sensitivity is dependent on canopy and background atmospheric ...

Michael T. Kiefer; Warren E. Heilman; Shiyuan Zhong; Joseph J. Charney; Xindi Bian

436

Neutron Energy Response and Background of Electrochemically Etched Nuclear Track Detectors: Study of Various CR-39 Materials  

Science Journals Connector (OSTI)

......Radiation Protection Dosimetry Article Neutron Energy Response and Background of Electrochemically Etched Nuclear Track Detectors: Study of Various CR-39...experiments. Results are presented for the energy dependence of the response of the various......

M. Luszik-Bhadra; W.G. Alberts; E. Piesch

1990-08-01T23:59:59.000Z

437

Small-angle neutron scattering and the errors in protein structures that arise from uncorrected background and intermolecular interactions  

Science Journals Connector (OSTI)

Making a complete background correction for SANS from solutions of biological macromolecules enables more accurate values for the calculated shapes and sizes of the molecules and leads to valid interpretations of solvation as well as the magnitudes of intermolecular interactions.

Rubinson, K.A.

2008-03-08T23:59:59.000Z

438

LIMITS ON THE STOCHASTIC GRAVITATIONAL WAVE BACKGROUND FROM THE NORTH AMERICAN NANOHERTZ OBSERVATORY FOR GRAVITATIONAL WAVES  

SciTech Connect

We present an analysis of high-precision pulsar timing data taken as part of the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) project. We have observed 17 pulsars for a span of roughly five years using the Green Bank and Arecibo radio telescopes. We analyze these data using standard pulsar timing models, with the addition of time-variable dispersion measure and frequency-variable pulse shape terms. Sub-microsecond timing residuals are obtained in nearly all cases, and the best rms timing residuals in this set are {approx}30-50 ns. We present methods for analyzing post-fit timing residuals for the presence of a gravitational wave signal with a specified spectral shape. These optimally take into account the timing fluctuation power removed by the model fit, and can be applied to either data from a single pulsar, or to a set of pulsars to detect a correlated signal. We apply these methods to our data set to set an upper limit on the strength of the nHz-frequency stochastic supermassive black hole gravitational wave background of h{sub c} (1 yr{sup -1}) < 7 Multiplication-Sign 10{sup -15} (95%). This result is dominated by the timing of the two best pulsars in the set, PSRs J1713+0747 and J1909-3744.

Demorest, P. B.; Ransom, S. [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903 (United States)] [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903 (United States); Ferdman, R. D.; Kaspi, V. M. [Department of Physics, McGill University, 3600 rue Universite, Montreal, QC H3A 2T8 (Canada)] [Department of Physics, McGill University, 3600 rue Universite, Montreal, QC H3A 2T8 (Canada); Gonzalez, M. E.; Stairs, I. H. [Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, BC V6T 1Z1 (Canada)] [Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, BC V6T 1Z1 (Canada); Nice, D. [Department of Physics, Lafayette College, Easton, PA 18042 (United States)] [Department of Physics, Lafayette College, Easton, PA 18042 (United States); Arzoumanian, Z. [Center for Research and Exploration in Space Science and Technology and X-Ray Astrophysics Laboratory, NASA Goddard Space Flight Center, Code 662, Greenbelt, MD 20771 (United States)] [Center for Research and Exploration in Space Science and Technology and X-Ray Astrophysics Laboratory, NASA Goddard Space Flight Center, Code 662, Greenbelt, MD 20771 (United States); Brazier, A.; Cordes, J. M. [Department of Astronomy, Cornell University, Ithaca, NY 14853 (United States)] [Department of Astronomy, Cornell University, Ithaca, NY 14853 (United States); Burke-Spolaor, S.; Lazio, J. [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91106 (United States)] [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91106 (United States); Chamberlin, S. J.; Ellis, J.; Giampanis, S. [Center for Gravitation, Cosmology and Astrophysics, Department of Physics, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, WI 53201 (United States)] [Center for Gravitation, Cosmology and Astrophysics, Department of Physics, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, WI 53201 (United States); Finn, L. S. [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States)] [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States); Freire, P. [Max-Planck-Institut fur Radioastronomie, D-53121 Bonn (Germany)] [Max-Planck-Institut fur Radioastronomie, D-53121 Bonn (Germany); Jenet, F. [Center for Gravitational Wave Astronomy, University of Texas at Brownsville, Brownsville, TX 78520 (United States)] [Center for Gravitational Wave Astronomy, University of Texas at Brownsville, Brownsville, TX 78520 (United States); Lommen, A. N. [Department of Physics and Astronomy, Franklin and Marshall College, P.O. Box 3003, Lancaster, PA 17604 (United States)] [Department of Physics and Astronomy, Franklin and Marshall College, P.O. Box 3003, Lancaster, PA 17604 (United States); McLaughlin, M. [Department of Physics, West Virginia University, P.O. Box 6315, Morgantown, WV 26505 (United States)] [Department of Physics, West Virginia University, P.O. Box 6315, Morgantown, WV 26505 (United States); and others

2013-01-10T23:59:59.000Z

439

Voluntary sexual exposure online among Swedish youth – social background, Internet behavior and psychosocial health  

Science Journals Connector (OSTI)

Abstract Studies have described the phenomenon of voluntary sexual exposure among youth online but only a few focus on the typical young person who has this experience. The purpose of this study was to investigate Swedish youth with experience of voluntary sexual exposure online, with regard to Internet behavior, social background, and psychosocial health including parent–child relationships. A representative sample of 3503 Swedish youths in their third year of high school completed a survey about Internet behavior, Internet-related sexual harassment, sexuality, health, and sexual abuse. Out of those taking part in the survey, 20.9% (19.2% boys and 22.3% girls) reported experiences of voluntary sexual exposure online. Multivariate analysis showed a significant association between voluntary sexual exposure online and a number of different forms of harassment online. Neither poorer psychosocial health nor problematic relationships with parents remained significant in the final model. The results underlined the fact that voluntary sexual exposure online is associated with vulnerability on the Internet among both boys and girls and that there is a need for parents and professionals to better understand what young people do on the Internet and the risks they may incur.

Linda S. Jonsson; Gisela Priebe; Marie Bladh; Carl Göran Svedin

2014-01-01T23:59:59.000Z

440

New Constraints on Cosmic Polarization Rotation from B-Mode Polarization in Cosmic Microwave Background  

E-Print Network (OSTI)

STPpol, POLARBEAR and BICEP2 have recently measured the cosmic microwave background (CMB) B-mode polarization in various sky regions of several tens of square degrees and obtained BB power spectra in the multipole range 20-3000, detecting the components due to gravitational lensing and to inflationary gravitational waves. We analyze jointly the results of these three experiments and propose modifications of their analysis of the spectra to include in the model, in addition to the gravitational lensing and the inflationary gravitational waves components, also the effects induced by the cosmic polarization rotation (CPR), if it exists within current upper limits. Although in principle our analysis would lead also to new constraints on CPR, in practice these can only be given on its fluctuations , since constraints on its mean angle are inhibited by the de-rotation which is applied by current CMB polarization experiments, in order to cope with the insufficient calibration of the polarization angle. The combined data fits from all three experiments (with 29% CPR-SPTpol correlation, depending on theoretical model) gives constraint ^1/2 areas observed by SPTpol, POLARBEAR and BICEP2.

Sperello di Serego Alighieri; Wei-Tou Ni; Wei-Ping Pan

2014-04-07T23:59:59.000Z

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441

Cosmological Parameters from Cosmic Background Imager Observations and Comparisons with BOOMERANG, DASI, and MAXIMA  

E-Print Network (OSTI)

We report on the cosmological parameters derived from observations with the Cosmic Background Imager (CBI), covering 40 square degrees and the multipole range 300 < l < 3500. The angular scales probed by the CBI correspond to structures which cover the mass range from 10^14 to 10^17 M_sun, and the observations reveal, for the first time, the seeds that gave rise to clusters of galaxies. These unique, high-resolution observations also show damping in the power spectrum to l ~ 2000, which we interpret as due to the finite width of the photon-baryon decoupling region and the viscosity operating at decoupling. Because the observations extend to much higher l the CBI results provide information complementary to that probed by the Boomerang, DASI, Maxima, and VSA experiments. As the observations are pushed to higher multipoles no anomalies relative to standard models appear, and extremely good consistency is found between the cosmological parameters derived for the CBI observations over the range 610 < l < 2000 and observations at lower l [abridged].

J. L. Sievers; J. R. Bond; J. K. Cartwright; C. R. Contaldi; B. S. Mason; S. T. Myers; S. Padin; T. J. Pearson; U. -L. Pen; D. Pogosyan; S. Prunet; A. C. S. Readhead; M. C. Shepherd; P. S. Udomprasert; L. Bronfman; W. L. Holzapfel; J. May

2002-05-23T23:59:59.000Z

442

Limits on the Polarization of the Cosmic Microwave Background Radiation at Multipoles up to l~2000  

E-Print Network (OSTI)

We report upper limits on the polarization of the CMBR as measured with the Cosmic Background Imager, a 13 element interferometer that operates in the 26-36 GHz band and is sited on Llano de Chajnantor in northern Chile. The array consists of 90-cm Cassegrain antennas mounted on a steerable platform that can be rotated about the optical axis to facilitate polarization observations. The CBI employs single-mode circularly polarized receivers and it samples multipoles from l~400 to l~3500. The polarization data were calibrated on 3C279 and Tau A. The polarization observations consist of 278 hours of data on two fields taken in 2000, during the first CBI observing season. A joint likelihood analysis of the two fields yields three upper limits (95% c.l.) for \\mathcal{C}_l^{EE} = C^{EE}l(l+1)/(2pi) under the assumption that \\mathcal{C}_l^{BB}=0: 49.0 microK^2 (l=603); 164 microK^2 (l=1144); and 630 microK^2 (l=2048).

J. K. Cartwright; T. J. Pearson; A. C. S. Readhead; M. C. Shepherd; J. L. Sievers; G. B. Taylor

2005-02-08T23:59:59.000Z

443

Study of v interactions and background estimation in the OPERA emulsion film detector  

E-Print Network (OSTI)

The OPERA (Oscillation Project with Emulsion tRacking Apparatus ) experiment or CNGS1 was approved in 2001 by CERN and presently is under construction. Data-taking is expected to start in 2006. The experiment is designated to the ?? ? ?? oscillation search. OPERA is a hybrid detector comprising a number of electronic detectors and a specially designed nuclear emulsion stack interlaced with lead plates. The total target mass of the detector will be about 1.8 kt. This impressive mass needed for neutrino detection is combined with an even more impressive spatial resolution of about a m , characteristic of the nuclear emulsion technique. The detection of ?? is based on the observation of the decay of the ? lepton. The fine grained structure of nuclear emulsions offers the possibility to directly observe such a decay and by the means of kinematical analysis can be clearly separated from background events. Nuclear emulsions will be produced and processed in industrial quantities and the readout will be don...

Janicskó-Csáthy, József

444

The Anisotropy of the Extragalactic Radio Background from Dark Matter Annihilation  

E-Print Network (OSTI)

Observations of the extragalactic radio background have uncovered a significant isotropic emission across multiple frequencies spanning from 22 MHz to 10 GHz. The intensity of this non-thermal emission component significantly exceeds the expected contribution from known astrophysical sources. Interestingly, models have indicated that the annihilation of dark matter particles may reproduce both the flux and spectrum of the excess. However, the lack of a measurable anisotropy in the residual emission remains challenging for both dark matter and standard astrophysical interpretations of the ARCADE-2 data. We calculate the expected synchrotron anisotropy from dark matter annihilation and show that these models can produce very small anisotropies, though this requires galaxy clusters to have large substructure contributions and strong magnetic fields. We show that this constraint can be significantly relaxed, however, in scenarios where electrons produced via dark matter annihilation can be efficiently reaccelerated by Alfv\\'en waves in the intra-Cluster medium. Our analysis indicates that any source capable of explaining the intensity and isotropy of the extragalactic radio excess must have a spatial extension far larger than typical for baryons in galaxies, suggesting a novel physics interpretation.

Ke Fang; Tim Linden

2014-12-23T23:59:59.000Z

445

Gravitational Wave Background from Neutrino-Driven Gamma-Ray Bursts  

E-Print Network (OSTI)

We discuss the gravitational wave background (GWB) from a cosmological population of gamma-ray bursts (GRBs). Among various emission mechanisms for the gravitational waves (GWs), we pay a particular attention to the vast anisotropic neutrino emissions from the accretion disk around the black hole formed after the so-called failed supernova explosions. The produced GWs by such mechanism are known as burst with memory, which could dominate over the low-frequency regime below \\sim 10Hz. To estimate their amplitudes, we derive general analytic formulae for gravitational waveform from the axisymmetric jets. Based on the formulae, we first quantify the spectrum of GWs from a single GRB. Then, summing up its cosmological population, we find that the resultant value of the density parameter becomes roughly \\Omega_{GW} \\approx 10^{-20} over the wide-band of the low-frequency region, f\\sim 10^{-4}-10^1Hz. The amplitude of GWB is sufficiently smaller than the primordial GWBs originated from an inflationary epoch and far below the detection limit.

Takashi Hiramatsu; Kei Kotake; Hideaki Kudoh; Atsushi Taruya

2005-09-27T23:59:59.000Z

446

QCD effective charge from the three-gluon vertex of the background-field method  

Science Journals Connector (OSTI)

In this article we study in detail the prospects of determining the infrared finite QCD effective charge from a special kinematic limit of the vertex function corresponding to three background gluons. This particular Green’s function satisfies a QED-like Ward identity, relating it to the gluon propagator, with no reference to the ghost sector. Consequently, its longitudinal form factors may be expressed entirely in terms of the corresponding gluon wave function, whose inverse is proportional to the effective charge. After reviewing certain important theoretical properties, we consider a typical lattice quantity involving this vertex, and derive its exact dependence on the various form factors, for arbitrary momenta. We then focus on the particular momentum configuration that eliminates any dependence on the (unknown) transverse form factors, projecting out only the desired quantity. A preliminary numerical analysis indicates that the effective charge is relatively insensitive to the numerical uncertainties that may afflict future simulations of the aforementioned lattice quantity. The numerical difficulties associated with a parallel determination of the dynamical gluon mass are briefly discussed.

D. Binosi; D. Ibañez; J. Papavassiliou

2013-06-17T23:59:59.000Z

447

The Distortion of the Cosmic Microwave Background by the Milky Way  

E-Print Network (OSTI)

The Milky Way can act as a large-scale weak gravitational lens of the cosmic microwave background (CMB). We study this effect using a photon ray-tracing code and a Galactic mass distribution with disk, bulge and halo components. For an observer at the Sun's coordinates in the Galaxy, the bending of CMB photon paths is limited to less than one arcsecond, and only for rays that pass within a few degrees of the Galactic Center. However, the entire sky is affected, resulting in global distortions of the CMB on large angular scales. These distortions can cause the low-order multipoles of a spherical harmonic expansion of the CMB sky temperature to leak into higher-order modes. Thus the component of the CMB dipole that results from the Local Group's motion relative to the local cosmic frame of rest contributes to higher-order moments for an observer in the solar system. With our ray-tracing code we show that the phenomenon is not sensitive to the specific choice of Galactic potential. We also quantitatively rule it...

Czaja, Benjamin

2014-01-01T23:59:59.000Z

448

Historical Background on Assessment the Performance of the Waste Isolation Pilot Plant  

SciTech Connect

In 1979, six years after selecting the Delaware Basin as a potential disposal area, Congress authorized the US Department of Energy to build the Waste Isolation Pilot Plant (WIPP) near Carlsbad, New Mexico, as a research and development facility for the safe management, storage, and disposal of waste contaminated with transuranic radioisotopes. In 1998, 19 years after authorization and 25 years after site selection, the US Environmental Protection Agency (EPA) certified that the WIPP disposal system complied with its regulations. The EPA's decision was primarily based on the results from a performance assessment conducted in 1996. This performance assessment was the culmination of four preliminary performance assessments conducted between 1989 and 1992. This report provides a historical setting and context for how the performance of the deep geologic repository at the WIPP was analyzed. Also included is background on political forces acting on the project. For example, the federal requirement to provide environmental impact statements and negotiated agreements with the State of New Mexico influenced the type of scientific areas that were investigated and the engineering analysis prior to 1989 for the WIPP.

Rechard, R.P.

1999-06-01T23:59:59.000Z

449

Neutron electric polarizability from unquenched lattice QCD using the background field approach  

E-Print Network (OSTI)

A calculational scheme for obtaining the electric polarizability of the neutron in lattice QCD with dynamical quarks is developed, using the background field approach. The scheme differs substantially from methods previously used in the quenched approximation, the physical reason being that the QCD ensemble is no longer independent of the external electromagnetic field in the dynamical quark case. One is led to compute (certain integrals over) four-point functions. Particular emphasis is also placed on the physical role of constant external gauge fields on a finite lattice; the presence of these fields complicates the extraction of polarizabilities, since it gives rise to an additional shift of the neutron mass unrelated to polarizability effects. The method is tested on a SU(3) flavor-symmetric ensemble furnished by the MILC Collaboration, corresponding to a pion mass of m_pi = 759 MeV. Disconnected diagrams are evaluated using stochastic estimation. A small negative electric polarizability of alpha =(-2.0 +/- 0.9) 10^(-4) fm^3 is found for the neutron at this rather large pion mass; this result does not seem implausible in view of the qualitative behavior of alpha as a function of m_pi suggested by Chiral Effective Theory.

Michael Engelhardt

2007-12-01T23:59:59.000Z

450

Re-Ionization and its Imprint on the Cosmic Microwave Background  

E-Print Network (OSTI)

Early reionization changes the pattern of anisotropies expected in the cosmic microwave background. To explore these changes, we derive from first principles the equations governing anisotropies, focusing on the interactions of photons with electrons. Vishniac (1987) claimed that second order terms can be large in a re-ionized Universe, so we derive equations correct to second order in the perturbations. There are many more second order terms than were considered by Vishniac. To understand the basic physics involved, we present a simple analytic approximation to the first order equation. Then turning to the sec- ond order equation, we show that the Vishniac term is indeed the only important one. We also present numerical results for a variety of ionization histories [in a standard cold dark matter Universe] and show quantitatively how the sig- nal in several experiments depends on the ionization history. The most pronounced indication of a re-ionized Universe would be seen in very small scale experiments; the expected signal in the Owens Valley experiment is smaller by a factor of order ten if the last scattering surface is at a redshift $z\\simeq100$ as it would be if the Universe were re-ionized very early. On slightly larger scales, the expected signal in a re-ionized Universe {\\it is} smaller than it would be with standard recombination, but only by a factor of two or so.

Scott Dodelson; Jay Jubas

1993-08-16T23:59:59.000Z

451

Low background high efficiency radiocesium detection system based on positron emission tomography technology  

Science Journals Connector (OSTI)

After the 2011 nuclear power plant accident at Fukushima radiocesium contamination in food became a serious concern in Japan. However low background and high efficiency radiocesium detectors are expensive and huge including semiconductor germanium detectors. To solve this problem we developed a radiocesium detector by employing positron emission tomography (PET) technology. Because 134Cs emits two gamma photons (795 and 605 keV) within 5 ps they can selectively be measured with coincidence. Such major environmental gamma photons as 40K (1.46 MeV) are single photon emitters and a coincidence measurement reduces the detection limit of radiocesium detectors. We arranged eight sets of Bi4 Ge 3O12 (BGO) scintillation detectors in double rings (four for each ring) and measured the coincidence between these detectors using PET data acquisition system. A 50 × 50 × 30 mm BGO was optically coupled to a 2 in. square photomultiplier tube (PMT). By measuring the coincidence we eliminated most single gamma photons from the energy distribution and only detected those from 134Cs at an average efficiency of 12%. The minimum detectable concentration of the system for the 100 s acquisition time is less than half of the food monitor requirements in Japan (25 Bq/kg). These results show that the developed radiocesium detector based on PET technology is promising to detect low level radiocesium.

Seiichi Yamamoto; Yoshimune Ogata

2013-01-01T23:59:59.000Z

452

On the ultra high energy cosmic rays and the origin of the cosmic microwave background radiation  

E-Print Network (OSTI)

Some inconsistencies to the assumption of a cosmological origin of the cosmic microwave background CMB, such as the absence of gravitational lensing in the WMAP data, open the doors to some speculations such as a local origin to the CMB. We argue here that this assumption agrees with the absence of the GZK cutoff (at least according to AGASA data) in the energy spectrum of the cosmic ray due to the cosmic interaction with the CMB at $6\\times 10^{19} eV$ or above. Within 50 Mpc from Earth, the matter and light distributions are close to an anisotropic distribution, where the local cluster and local super-clusters of galaxies can be identified. In contrast, the ultra high energy comic rays data is consistent to an almost isotropic distribution, and there is no correlation between their arrival direction and astronomical sources within our local cluster. This means that the events above the GZK cutoff come from distances above 50 Mpc, without an apparent energy loss. This scenario is plausible under the assumption of the CMB concentrated only within 3-4 Mpc from Earth. In other words, the CMB has a local origin linked only to the local super-cluster of galaxies. In addition, the galactic and extragalactic energy spectra index within the energy equipartition theorem strongly constrains the dark matter and dark energy hypothesis, essential in the Big Bang cosmology.

C. E. Navia; C. R. A. Augusto; K. H. Tsui

2007-07-12T23:59:59.000Z

453

Thin-shell bubbles and information loss problem in anti de Sitter background  

E-Print Network (OSTI)

We study the motion of thin-shell bubbles and their tunneling in anti de Sitter (AdS) background. We are interested in the case when the outside of a shell is a Schwarzschild-AdS space (false vacuum) and the inside of it is an AdS space with a lower vacuum energy (true vacuum). If a collapsing true vacuum bubble is created, classically it will form a Schwarzschild-AdS black hole. However, this collapsing bubble can tunnel to a bouncing bubble that moves out to spatial infinity. Then, although the classical causal structure of a collapsing true vacuum bubble has the singularity and the event horizon, quantum mechanically the wavefunction has support for a history without any singularity nor event horizon which is mediated by the non-perturbative, quantum tunneling effect. This may be regarded an explicit example that shows the unitarity of an asymptotic observer in AdS, while a classical observer who only follows the most probable history effectively lose information due to the formation of an event horizon.

Misao Sasaki; Dong-han Yeom

2014-12-25T23:59:59.000Z

454

Cosmogenic Backgrounds in Borexino at 3800 m water-equivalent depth  

SciTech Connect

The solar neutrino experiment Borexino, which is located in the Gran Sasso underground laboratories, is in a unique position to study muon-induced backgrounds in an organic liquid scintillator. In this study, a large sample of cosmic muons is identified and tracked by a muon veto detector external to the liquid scintillator, and by the specific light patterns observed when muons cross the scintillator volume. The yield of muon-induced neutrons is found to be Y{sub n} = (3.10±0.11)·10{sup ?4} n/(?·(g/cm{sup 2})). The distance profile between the parent muon track and the neutron capture point has the average value ? = (81.5±2.7) cm. Additionally the yields of a number of cosmogenic radioisotopes are measured for {sup 12}N, {sup 12}B, {sup 8}He, {sup 9}C, {sup 9}Li, {sup 8}B, {sup 6}He, {sup 8}Li, {sup 11}Be, {sup 10}C and {sup 11}C. All results are compared with Monte Carlo simulation predictions using the FLUKA and GEANT4 packages. General agreement between data and simulation is observed for the cosmogenic production yields with a few exceptions, the most prominent case being {sup 11}C yield for which both codes return about 50% lower values. The predicted ?-n distance profile and the neutron multiplicity distribution are found to be overall consistent with data.

Bellini, G.; Avanzini, M. Buizza; Caccianiga, B.; D'Angelo, D. [Dipartimento di Fisica, Università degli Studi e INFN, Milano 20133 (Italy); Benziger, J. [Chemical Engineering Department, Princeton University, Princeton, NJ 08544 (United States); Bick, D. [University of Hamburg, Hamburg (Germany); Bonfini, G.; Cavalcante, P.; Fomenko, K. [INFN Laboratori Nazionali del Gran Sasso, Assergi 67010 (Italy); Bravo, D. [Physics Department, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061 (United States); Cadonati, L. [Physics Department, University of Massachusetts, Amherst 01003 (United States); Calaprice, F.; Chavarria, A.; Galbiati, C. [Physics Department, Princeton University, Princeton, NJ 08544 (United States); Chepurnov, A. [Lomonosov Moscow State University Skobeltsyn Institute of Nuclear Physics, Moscow 119234 (Russian Federation); Davini, S.; Empl, A. [Department of Physics, University of Houston, Houston, TX 77204 (United States); Derbin, A. [St. Petersburg Nuclear Physics Institute, Gatchina 188350 (Russian Federation); Etenko, A. [NRC Kurchatov Institute, Moscow 123182 (Russian Federation); Franco, D., E-mail: spokeperson-borex@lngs.infn.it [APC, Univ. Paris Diderot, CNRS/IN2P3, CEA/Irfu, Obs. de Paris, Sorbonne Paris Cité (France); and others

2013-08-01T23:59:59.000Z

455

Constraints on primordial magnetic fields from the optical depth of the cosmic microwave background  

E-Print Network (OSTI)

Damping of magnetic fields via ambipolar diffusion and decay of magnetohydrodynamical (MHD) turbulence in the post decoupling era heats the intergalactic medium (IGM). Collisional ionization weakly ionizes the IGM, producing an optical depth to scattering of the cosmic microwave background (CMB). The optical depth generated at $z\\gg 10$ does not affect the "reionization bump" of the CMB polarization power spectrum at low multipoles, but affects the temperature and polarization power spectra at high multipoles. Using the Planck 2013 temperature and lensing data together with the WMAP 9-year polarization data, we constrain the present-day field strength, $B_0$, smoothed over the damping length at the decoupling epoch as a function of the spectral index, $n_B$. We find the 95% upper bounds of $B_0<0.56$, 0.31, and 0.14 nG for $n_B=-2.9$, $-2.5$, and $-1.5$, respectively. For these spectral indices, the optical depth is dominated by dissipation of the decaying MHD turbulence that occurs shortly after the decou...

Kunze, Kerstin E

2015-01-01T23:59:59.000Z

456

Background monitoring of air toxics at the Waste Isolation Pilot Plant  

SciTech Connect

The Waste Isolation Pilot Plant (WIPP), located southeast of Carlsbad, New Mexico, has been constructed as a permanent repository for containerized solid or solidified transuranic (TRU) mixed waste. The repository is constructed in a massive salt bed formation, 2,150 feet below the surface. The WIPP has been granted a No-Migration Variance by the US Environmental Protection Agency (EPA) according to the requirements of 40 CFR 268.6. As part of the variance, a detailed air monitoring program has been developed for the facility. The purpose of the program is to detect airborne releases of hazardous constituents at the earliest practicable time. Routine background monitoring for volatile organic compounds (VOCs) has been performed at WIPP for the last two years. The monitoring program routinely quantifies airborne concentrations of five VOCs in the ventilation airstream of the underground facility, using Compendium Method TO-14. This paper describes the monitoring program in-place at the facility and presents a summary of the monitoring results for the last two years.

Frank-Supka, L.; Wu, C.F.; Lopez, R.H. [Westinghouse Electric Corp., Carlsbad, NM (United States). Waste Isolation Div.; Zimmer, R.A. [Harding Lawson Associates, Denver, CO (United States)

1994-12-31T23:59:59.000Z

457

A new scenario framework for climate change research: background, process, and future directions  

SciTech Connect

The scientific community is developing new integrated global, regional, and sectoral scenarios to facilitate interdisciplinary research and assessment to explore the range of possible future climates and related physical changes could pose to human and natural systems; how these could interact with social, economic, and environmental development pathways; the degree to which mitigation and adaptation policies can avoid and reduce those risks; the costs and benefits of various policy mixes; residual impacts under alternative pathways; and the relationship with sustainable development. This paper provides the background to, and process of, developing the conceptual framework for these scenarios, described in three other papers in this Special Issue (van Vuuren et al.; O'Neill et al.; Kriegler et al.). The paper also discusses research needs to further develop and apply this framework. The goal is to encourage climate change researchers from a broad range of perspectives and disciplines to work together to develop policy-relevant scenarios and explore the implications of different possible futures for the challenges and opportunities human and natural systems could face with increasing climate change.

Ebi, Kristie L.; Hallegatte, Stephane; Kram, Tom; Arnell, Nigel; Carter, Tim; Edmonds, James A.; Kriegler, Elmar; Mathur, Ritu; O'Neill, Brian; Riahi, Keywan; Winkler, Harald; Van Vuuren, Detlef; Zwickel, Timm

2014-02-01T23:59:59.000Z

458

Heavy sterile neutrinos, entropy and relativistic energy production, and the relic neutrino background  

E-Print Network (OSTI)

We explore the implications of the existence of heavy neutral fermions (i.e., sterile neutrinos) for the thermal history of the early universe. In particular, we consider sterile neutrinos with rest masses in the 100 MeV to 500 MeV range, with couplings to ordinary active neutrinos large enough to guarantee thermal and chemical equilibrium at epochs in the early universe with temperatures T > 1 GeV, but in a range to give decay lifetimes from seconds to minutes. Such neutrinos would decouple early, with relic densities comparable to those of photons, but decay out of equilibrium, with consequent prodigious entropy generation prior to, or during, Big Bang Nucleosynthesis (BBN). Most of the ranges of sterile neutrino rest mass and lifetime considered are at odds with Cosmic Microwave Background (CMB) limits on the relativistic particle contribution to energy density (e.g., as parameterized by N_eff). However, some sterile neutrino parameters can lead to an acceptable N_eff. These parameter ranges are accompanie...

Fuller, George M; Kusenko, Alexander

2011-01-01T23:59:59.000Z

459

Effect of a chameleon scalar field on the cosmic microwave background  

Science Journals Connector (OSTI)

We show that a direct coupling between a chameleonlike scalar field and photons can give rise to a modified Sunyaev-Zel’dovich (SZ) effect in the cosmic microwave background (CMB). The coupling induces a mixing between chameleon particles and the CMB photons when they pass through the magnetic field of a galaxy cluster. Both the intensity and the polarization of the radiation are modified. The degree of modification depends strongly on the properties of the galaxy cluster such as magnetic field strength and electron number density. Existing SZ measurements of the Coma cluster enable us to place constraints on the photon-chameleon coupling. The constrained conversion probability in the cluster is PComa(204??GHz)<6.2×10-5 at 95% confidence, corresponding to an upper bound on the coupling strength of geff(cell)<2.2×10-8??GeV-1 or geff(Kolmo)<(7.2–32.5)×10-10??GeV-1, depending on the model that is assumed for the cluster magnetic field structure. We predict the radial profile of the chameleonic CMB intensity decrement. We find that the chameleon effect extends farther toward the edges of the cluster than the thermal SZ effect. Thus we might see a discrepancy between the x-ray emission data and the observed SZ intensity decrement. We further predict the expected change to the CMB polarization arising from the existence of a chameleonlike scalar field. These predictions could be verified or constrained by future CMB experiments.

Anne-Christine Davis; Camilla A. O. Schelpe; Douglas J. Shaw

2009-09-10T23:59:59.000Z

460

One-loop energy-momentum tensor in QED with electric-like background  

E-Print Network (OSTI)

We have obtained nonperturbative one-loop expressions for the mean energy-momentum tensor and current density of Dirac's field on a constant electric-like background. One of the goals of this calculation is to give a consistent description of back-reaction in such a theory. Two cases of initial states are considered: the vacuum state and the thermal equilibrium state. First, we perform calculations for the vacuum initial state. In the obtained expressions, we separate the contributions due to particle creation and vacuum polarization. The latter contributions are related to the Heisenberg-Euler Lagrangian. Then, we study the case of the thermal initial state. Here, we separate the contributions due to particle creation, vacuum polarization, and the contributions due to the work of the external field on the particles at the initial state. All these contributions are studied in detail, in different regimes of weak and strong fields and low and high temperatures. The obtained results allow us to establish restrictions on the electric field and its duration under which QED with a strong constant electric field is consistent. Under such restrictions, one can neglect the back-reaction of particles created by the electric field. Some of the obtained results generalize the calculations of Heisenberg-Euler for energy density to the case of arbitrary strong electric fields.

S. P. Gavrilov; D. M. Gitman

2007-09-12T23:59:59.000Z

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461

Applied Ecosystem Analysis - Background : EDT the Ecosystem Diagnosis and Treatment Method.  

SciTech Connect

This volume consists of eight separate reports. We present them as background to the Ecosystem Diagnosis and Treatment (EDT) methodology. They are a selection from publications, white papers, and presentations prepared over the past two years. Some of the papers are previously published, others are currently being prepared for publication. In the early to mid 1980`s the concern for failure of both natural and hatchery production of Columbia river salmon populations was widespread. The concept of supplementation was proposed as an alternative solution that would integrate artificial propagation with natural production. In response to the growing expectations placed upon the supplementation tool, a project called Regional Assessment of Supplementation Project (RASP) was initiated in 1990. The charge of RASP was to define supplementation and to develop guidelines for when, where and how it would be the appropriate solution to salmon enhancement in the Columbia basin. The RASP developed a definition of supplementation and a set of guidelines for planning salmon enhancement efforts which required consideration of all factors affecting salmon populations, including environmental, genetic, and ecological variables. The results of RASP led to a conclusion that salmon issues needed to be addressed in a manner that was consistent with an ecosystem approach. If the limitations and potentials of supplementation or any other management tool were to be fully understood it would have to be within the context of a broadly integrated approach - thus the Ecosystem Diagnosis and Treatment (EDT) method was born.

Mobrand, Lars E.

1996-05-01T23:59:59.000Z

462

Synoptic Sky Surveys and the Diffuse Supernova Neutrino Background: Removing Astrophysical Uncertainties and Revealing Invisible Supernovae  

E-Print Network (OSTI)

The cumulative (anti)neutrino production from all core-collapse supernovae within our cosmic horizon gives rise to the diffuse supernova neutrino background (DSNB), which is on the verge of detectability. The observed flux depends on supernova physics, but also on the cosmic history of supernova explosions; currently, the cosmic supernova rate introduces a substantial (+/-40%) uncertainty, largely through its absolute normalization. However, a new class of wide-field, repeated-scan (synoptic) optical sky surveys is coming online, and will map the sky in the time domain with unprecedented depth, completeness, and dynamic range. We show that these surveys will obtain the cosmic supernova rate by direct counting, in an unbiased way and with high statistics, and thus will allow for precise predictions of the DSNB. Upcoming sky surveys will substantially reduce the uncertainties in the DSNB source history to an anticipated +/-5% that is dominated by systematics, so that the observed high-energy flux thus will test supernova neutrino physics. The portion of the universe (z invisible supernovae, which may be unseen either due to unexpected large dust obscuration in host galaxies, or because some core-collapse events proceed directly to black hole formation and fail to give an optical outburst.

Amy Lien; Brian D. Fields; John F. Beacom

2010-01-20T23:59:59.000Z

463

Background rejection for the IBIS telescope based on compton kinematics: Experimental tests and Montecarlo simulations  

SciTech Connect

IBIS (Imager on Board the Integral Satellite) is dedicated to fine imaging in the gamma-ray energy range. The imaging performances are achieved using a coded mask aperture system in conjunction with a position sensitive detector made of two layers. This multilayer structure of position sensitive detectors allows the application of Compton kinematics for background rejection. In order to determine the efficacy of this method, a reduced scale prototype of the instrument has been developed. The detection apparatus is composed by two scintillation matrices of 5x5 elements in the same configuration of IBIS. The upper layer pixel size is 13 x 13 x 3 mm whereas the lower layer pixel size is 13 x 13 x 30 mm. An hybrid technology electronics has been setup for signals shaping and discrimination, moreover a custom software package has been developed for system calibration and data analysis. The equipment has been tested at different energies by employing radioactive sources. The results are presented and compared, when possible, with Montecarlo simulations.

Di Cocco, G.; De Cesare, G.; Grassi, D. [Istituto TeSRE/CNR, Bologna (Italy)] [and others

1996-12-31T23:59:59.000Z

464

Measurements of the cosmic microwave background temperature at 1. 47 GHz  

SciTech Connect

A radiofrequency-gain total power radiometer measured the intensity of the cosmic microwave background (CMB) at a frequency of 1.47 GHz (20.4 cm wavelength) from White Mountain, California, in September 1988 and from the South Pole, Antarctica, in December 1989. The CMB thermodynamic temperature, TCMB, is 2.27 {plus minus} 0.25 K (68% C.L.) measured from White Mountain and 2.26 {plus minus} 0.21 K from the South Pole site. The combined result is 2.27 {plus minus} 0.19 K. The correction for galactic emission has been derived from scaled low-frequency maps and constitutes the main source, of error. The atmospheric signal is found by extrapolation from zenith scan measurements at higher frequencies. The result is consistent with previous low-frequency measurements, including a measurement at 1.41 GHz (Levin et al. 1988) made with an earlier version of this instrument. The result is {approximately}2.5 {sigma} ({approximately}l% probability) from the 2.74 {plus minus} 0.02,K global average CMB temperature.

Bensadoun, M.J.

1991-11-01T23:59:59.000Z

465

Measurements of the cosmic microwave background temperature at 1.47 GHz  

SciTech Connect

A radiofrequency-gain total power radiometer measured the intensity of the cosmic microwave background (CMB) at a frequency of 1.47 GHz (20.4 cm wavelength) from White Mountain, California, in September 1988 and from the South Pole, Antarctica, in December 1989. The CMB thermodynamic temperature, TCMB, is 2.27 {plus_minus} 0.25 K (68% C.L.) measured from White Mountain and 2.26 {plus_minus} 0.21 K from the South Pole site. The combined result is 2.27 {plus_minus} 0.19 K. The correction for galactic emission has been derived from scaled low-frequency maps and constitutes the main source, of error. The atmospheric signal is found by extrapolation from zenith scan measurements at higher frequencies. The result is consistent with previous low-frequency measurements, including a measurement at 1.41 GHz (Levin et al. 1988) made with an earlier version of this instrument. The result is {approximately}2.5 {sigma} ({approximately}l% probability) from the 2.74 {plus_minus} 0.02,K global average CMB temperature.

Bensadoun, M.J.

1991-11-01T23:59:59.000Z

466

Cosmic neutrino background absorption line in the neutrino spectrum at IceCube  

Science Journals Connector (OSTI)

The IceCube experiment has recently reported a high energy neutrino spectrum between the TeV and PeV scales. The observed neutrino flux can be as a whole well fitted by a simple power law of the neutrino energy E?, E???? (???2). As a notable feature of the spectrum, however, it has a gap between 500 TeV and 1 PeV. Although the existence of the gap in the neutrino spectrum is not statistically significant at this point, it is very enticing to ask whether it might hint at some physics beyond the Standard Model. In this paper, we investigate a possibility that the gap can be interpreted as an absorption line in the power-law spectrum by the cosmic neutrino background through a new resonance in the MeV range. We also show that the absorption line has rich information about not only the MeV scale new particle but also the neutrino masses as well as the distances to the astrophysical sources of the high energy neutrinos. Viable models to achieve this possibility are also discussed.

Masahiro Ibe and Kunio Kaneta

2014-09-24T23:59:59.000Z

467

Gravitational radiation from cosmic (super)strings: Bursts, stochastic background, and observational windows  

SciTech Connect

The gravitational wave (GW) signals emitted by a network of cosmic strings are reexamined in view of the possible formation of a network of cosmic superstrings at the end of brane inflation. The reconnection probability p of intersecting fundamental or Dirichlet strings might be much smaller than 1, and the properties of the resulting string network may differ significantly from those of ordinary strings (which have p=1). In addition, it has been recently suggested that the typical length of newly formed loops may differ by a factor {epsilon}<<1 from its standard estimate. Here, we analyze the effects of the two parameters p and {epsilon} on the GW signatures of strings. We consider both the GW bursts emitted from cusps of oscillating string loops, which have been suggested as candidate sources for the LIGO/VIRGO and LISA interferometers, and the stochastic GW background, which may be detectable by pulsar-timing observations. In both cases we find that previously obtained results are quite robust, at least when the loop sizes are not suppressed by many orders of magnitude relative to the standard scenario. We urge pulsar observers to reanalyze a recently obtained 17-yr combined data set to see whether the large scatter exhibited by a fraction of the data might be due to a transient GW burst activity of some sort, e.g., to a near cusp event.

Damour, Thibault [Institut des Hautes Etudes Scientifiques, 91440 Bures-sur-Yvette (France); Vilenkin, Alexander [Institute of Cosmology, Department of Physics and Astronomy, Tufts University, Medford, Massachusetts 02155 (United States)

2005-03-15T23:59:59.000Z

468

Final report on the Background Soil Characterization Project at the Oak Ridge Reservation, Oak Ridge, Tennessee. Volume 3: Project Plan  

SciTech Connect

The Background Soil Characterization Project (BSCP) will provide background concentration levels of selected metals, organic compounds, and radionuclides in soils from uncontaminated on-site areas at the Oak Ridge Reservation (ORR), and off-site in the western part of Roane County and the eastern part of Anderson County. The BSCP will establish a database, recommend how to use the data for contaminated site assessment, and provide estimates of the potential human health and environmental risks associated with the background level concentrations of potentially hazardous constituents. ORR background soil characterization data will be used for two purposes. The first application will be in differentiating between naturally occurring constituents and site-related contamination. This is a very important step in a risk assessment because if sufficient background data are not available, no constituent known to be a contaminant can be eliminated from the assessment even if the sampled concentration is measured at a minimum level. The second use of the background data will be in calculating baseline risks against which site-specific contamination risks can be compared.

Hatmaker, T.L.; Hook, L.A.; Jackson, B.L. [and others

1993-10-01T23:59:59.000Z

469

Extending the Sensitivity to the Detection of WIMP Dark Matter with an Improved Understanding of the Limiting Neutron Backgrounds  

SciTech Connect

The Cryogenic Dark Matter Search (CDMS) uses position-sensitive Germanium and Silicon crystals in the direct detection of Weakly Interacting Massive Particles (WIMPs) believed to constitute most of the dark matter in the Universe. WIMP interactions with matter being rare, identifying and eliminating known backgrounds is critical for detection. Event-by-event discrimination by the detectors rejects the predominant gamma and beta backgrounds while Monte Carlo simulations help estimate, and subtract, the contribution from the neutrons. This thesis describes the effort to understand neutron backgrounds as seen in the two stages of the CDMS search for WIMPs. The first stage of the experiment was at a shallow site at the Stanford Underground Facility where the limiting background came from high-energy neutrons produced by cosmic-ray muon interactions in the rock surrounding the cavern. Simulations of this background helped inform the analysis of data from an experimental run at this site and served as input for the background reduction techniques necessary to set new exclusion limits on the WIMP-nucleon cross-section, excluding new parameter space for WIMPs of masses 8-20 GeV/c{sup 2}. This thesis considers the simulation methods used as well as how various event populations in the data served as checks on the simulations to allow them to be used in the interpretation of the WIMP-search data. The studies also confirmed the presence of a limiting neutron background at the shallow site, necessitating the move to the 713-meter deep Soudan Underground Facility. Similar computer-based studies helped quantify the neutron background seen at the deeper site and informed the analysis of the data emerging from the first physics run of the experiment at Soudan. In conjunction with the WIMP-search and calibration data, the simulations confirmed that increased depth considerably reduced the neutron backgrounds seen, greatly improving the sensitivity to WIMP detection. The data run set an upper limit of 4 x 10{sup -43} on the WIMP-nucleon cross section for a WIMP mass of 60 GeV/c{sup 2} . Upper limits to the rate of background neutrons have also been determined.

Kamat, Sharmila; /Case Western Reserve U.; ,

2005-01-01T23:59:59.000Z

470

The Space Density of Compton-Thick Active Galactic Nucleus and the X-Ray Background  

Science Journals Connector (OSTI)

We constrain the number density and evolution of Compton-thick (CT) active galactic nuclei (AGNs). In the local universe, we use the wide-area surveys from the Swift and INTEGRAL satellites, while for high redshifts we explore candidate selections based on a combination of X-ray and mid-infrared (mid-IR) parameters. We find a significantly lower space density of CT AGNs in the local universe than expected from published AGN population synthesis models to explain the X-ray background (XRB). This can be explained by the numerous degeneracies in the parameters of those models; we use the high-energy surveys described here to remove those degeneracies. We show that only direct observations of CT AGNs can currently constrain the number of heavily obscured supermassive black holes. At high redshift, the inclusion of IR-selected CT AGN candidates leads to a much higher space density, implying (1) a different (steeper) evolution for these sources compared to less-obscured AGNs, (2) that the IR selection includes a large number of interlopers, and/or (3) that there is a large number of reflection-dominated AGNs missed in the INTEGRAL and Swift observations. The contribution of CT AGN to the XRB is small, ~9%, with a comparable contribution to the total cosmic accretion, unless reflection-dominated CT AGNs significantly outnumber transmission-dominated CT AGNs, in which case their contribution can be much higher. Using estimates derived here for the accretion luminosity over cosmic time, we estimate the local mass density in supermassive black holes and find a good agreement with available constraints for an accretion efficiency of ~10%. Transmission-dominated CT AGNs contribute only ~8% to total black hole growth.

E. Treister; C. Megan Urry; Shanil Virani

2009-01-01T23:59:59.000Z

471

Anisotropic dissipative effects on the buoyancy instability with background heat flux  

SciTech Connect

The linear buoyancy instability in magnetized plasmas is investigated in the presence of anisotropic resistivity and viscosity by taking into account the background heat flux. The magnetic field is assumed to be homogeneous and has both horizontal and vertical components. The heat is primarily transported along the magnetic force lines when the gyro radius is much less than the mean collision free path. The Hall term is examined first and shows a damping effect on the magnetothermal instability. The heat-flux-driven buoyancy instability (HBI) is then investigated by taking into account the parallel resistivity (PR), cross-field resistivity (CR), and the anisotropic viscosity. The general dispersion relation (DR) is derived and discussed in several special cases. We show that only the CR and viscosity exert effects on the DR in the first case. The critical condition for the occurrence of HBI is modified by the CR coupled with the viscosity and the value of the instability growth rate is diminished by them. The effects due to the PR (resp. viscosity) on the HBI are examined next. The PR (resp. viscosity) is shown to alter not only the growth rate but also the instability criterion. There exists an unstable mode when the temperature decreases in the direction of gravity while this case is proven to be magnetothermally stable in the ideal magnetohydrodynamic limit. A new unstable mode is solely induced by the presence of PR (resp. viscosity). When the PR and CR are both taken into account, the resistivity is shown to induce a damping mode rather than an instability. Finally, considering the PR and viscosity simultaneously, it is found that a new unstable mode is excited when the PR is not equal to the viscosity, or else, dissipation effects do not alter the instability criterion and just cut down the growth rate.

Ren Haijun; Wu Zhengwei [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong); CAS Key Laboratory of Basic Plasma Physics, University of Science and Technology of China, Hefei 230026 (China); Cao Jintao [CAS Key Laboratory of Basic Plasma Physics, University of Science and Technology of China, Hefei 230026 (China); Chu, Paul K. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong)

2011-03-15T23:59:59.000Z

472

SYSTEMATIC EFFECTS IN INTERFEROMETRIC OBSERVATIONS OF THE COSMIC MICROWAVE BACKGROUND POLARIZATION  

SciTech Connect

The detection of the primordial B-mode spectrum of the polarized cosmic microwave background (CMB) signal may provide a probe of inflation. However, observation of such a faint signal requires excellent control of systematic errors. Interferometry proves to be a promising approach for overcoming such a challenge. In this paper we present a complete simulation pipeline of interferometric observations of CMB polarization, including systematic errors. We employ two different methods for obtaining the power spectra from mock data produced by simulated observations: the maximum likelihood method and the method of Gibbs sampling. We show that the results from both methods are consistent with each other as well as, within a factor of six, with analytical estimates. Several categories of systematic errors are considered: instrumental errors, consisting of antenna gain and antenna coupling errors; and beam errors, consisting of antenna pointing errors, beam cross-polarization, and beam shape (and size) errors. In order to recover the tensor-to-scalar ratio, r, within a 10% tolerance level, which ensures the experiment is sensitive enough to detect the B-signal at r = 0.01 in the multipole range 28 < l < 384, we find that, for a QUBIC-like experiment, Gaussian-distributed systematic errors must be controlled with precisions of |g{sub rms}| = 0.1 for antenna gain, |{epsilon}{sub rms}| = 5 Multiplication-Sign 10{sup -4} for antenna coupling, {delta}{sub rms} Almost-Equal-To 0. Degree-Sign 7 for pointing, {zeta}{sub rms} Almost-Equal-To 0. Degree-Sign 7 for beam shape, and {mu}{sub rms} = 5 Multiplication-Sign 10{sup -4} for beam cross-polarization. Although the combined systematic effects produce a tolerance level on r twice as large for an experiment with linear polarizers, the resulting bias in r for a circular experiment is 15% which is still on the level of desirable sensitivity.

Karakci, Ata; Korotkov, Andrei; Tucker, Gregory S. [Department of Physics, Brown University, 182 Hope Street, Providence, RI 02912 (United States); Zhang Le; Timbie, Peter [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Sutter, P. M.; Wandelt, Benjamin D. [Department of Physics, 1110 W. Green Street, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States); Bunn, Emory F., E-mail: ata_karakci@brown.edu [Physics Department, University of Richmond, Richmond, VA 23173 (United States)

2013-07-15T23:59:59.000Z

473

Exact Solutions to Force-Free Electrodynamics in Black Hole Backgrounds  

E-Print Network (OSTI)

A shared property of several of the known exact solutions to the equations of force-free electrodynamics is that their charge-current four-vector is \\textit{null}. We examine the general properties of null-current solutions and then focus on the principal congruences of the Kerr black hole spacetime. We obtain a large class of exact solutions, which are in general time-dependent and non-axisymmetric. These solutions include waves that, surprisingly, propagate without scattering on the curvature of the black hole's background. They may be understood as generalizations to Robinson's solutions to vacuum electrodynamics associated with a shear-free congruence of null geodesics. When stationary and axisymmetric, our solutions reduce to those of Menon and Dermer, the only previously known solutions in Kerr. In Kerr, all of our solutions have null electromagnetic fields ($\\vec{E} \\cdot \\vec{B} = 0$ and $E^2=B^2$). However, in Schwarzschild or flat spacetime there is freedom to add a magnetic monopole field, making the solutions magnetically dominated ($B^2>E^2$). This freedom may be used to reproduce the various flat-spacetime and Schwarzschild-spacetime (split) monopole solutions available in the literature (due to Michel and later authors), and to obtain a large class of time-dependent, non-axisymmetric generalizations. These generalizations may be used to model the magnetosphere of a conducting star that rotates with arbitrary prescribed time-dependent rotation axis and speed. We thus significantly enlarge the class of known exact solutions, while organizing and unifying previously discovered solutions in terms of their null structure.

T. Daniel Brennan; Samuel E. Gralla; Ted Jacobson

2013-10-10T23:59:59.000Z

474

Human exposure to high natural background radiation: what can it teach us about  

Science Journals Connector (OSTI)

Natural radiation is the major source of human exposure to ionising radiation, and its largest contributing component to effective dose arises from inhalation of 222Rn and its radioactive progeny. However, despite extensive knowledge of radiation risks gained through epidemiologic investigations and mechanistic considerations, the health effects of chronic low-level radiation exposure are still poorly understood. The present paper reviews the possible contribution of studies of populations living in high natural background radiation (HNBR) areas (Guarapari, Brazil; Kerala, India; Ramsar, Iran; Yangjiang, China), including radon-prone areas, to low dose risk estimation. Much of the direct information about risk related to HNBR comes from case–control studies of radon and lung cancer, which provide convincing evidence of an association between long-term protracted radiation exposures in the general population and disease incidence. The success of these studies is mainly due to the careful organ dose reconstruction (with relatively high doses to the lung), and to the fact that large-scale collaborative studies have been conducted to maximise the statistical power and to ensure the systematic collection of information on potential confounding factors. In contrast, studies in other (non-radon) HNBR areas have provided little information, relying mainly on ecological designs and very rough effective dose categorisations. Recent steps taken in China and India to establish cohorts for follow-up and to conduct nested case–control studies may provide useful information about risks in the future, provided that careful organ dose reconstruction is possible and information is collected on potential confounding factors.

Jolyon H Hendry; Steven L Simon; Andrzej Wojcik; Mehdi Sohrabi; Werner Burkart; Elisabeth Cardis; Dominique Laurier; Margot Tirmarche; Isamu Hayata

2009-01-01T23:59:59.000Z

475

Cosmic Microwave Background Temperature and Polarization Anisotropy in Brans-Dicke Cosmology  

E-Print Network (OSTI)

We develop a formalism for calculating cosmic microwave background (CMB) temperature and polarization anisotropies in cosmological models with Brans-Dicke gravity. We then modify publicly available Boltzmann codes to calculate numerically the temperature and polarization power spectra. Results are illustrated with a few representative models. Comparing with the general-relativistic model with the same cosmological parameters, both the amplitude and the width of the acoustic peaks are different in the Brans-Dicke models. We use a covariance-matrix calculation to investigate whether the effects of Brans-Dicke gravity are degenerate with those of variation in other cosmological parameters and to simultaneously determine whether forthcoming CMB maps might be able to distinguish Brans-Dicke and general-relativistic cosmology. Although the predicted power spectra for plausible Brans-Dicke models differ from those in general relativity only slightly, we find that MAP and/or the Planck Surveyor may in principle provide a test of Brans-Dicke theory that is competitive to solar-system tests. For example, if all other parameters except for the CMB normalization are fixed, a value of the Brans-Dicke parameter omega as large as 500 could be identified with MAP, and for Planck, values as large as omega \\simeq3000 could be identified; these sensitivities are decreased roughly by a factor of 3 if we marginalize over the baryon density, Hubble constant, spectral index, and reionization optical depth. In more general scalar-tensor theories, omega may evolve with time, and in this case, the CMB probe would be complementary to that from solar-system tests.

Xuelei Chen; Marc Kamionkowski

1999-05-27T23:59:59.000Z

476

Improved Upper Limits on the Stochastic Gravitational-Wave Background from 2009-2010 LIGO and Virgo Data  

E-Print Network (OSTI)

Gravitational waves from a variety of sources are predicted to superpose to create a stochastic background. This background is expected to contain unique information from throughout the history of the universe that is unavailable through standard electromagnetic observations, making its study of fundamental importance to understanding the evolution of the universe. We carry out a search for the stochastic background with the latest data from LIGO and Virgo. Consistent with predictions from most stochastic gravitational-wave background models, the data display no evidence of a stochastic gravitational-wave signal. Assuming a gravitational-wave spectrum of Omega_GW(f)=Omega_alpha*(f/f_ref)^alpha, we place 95% confidence level upper limits on the energy density of the background in each of four frequency bands spanning 41.5-1726 Hz. In the frequency band of 41.5-169.25 Hz for a spectral index of alpha=0, we constrain the energy density of the stochastic background to be Omega_GW(f)<5.6x10^-6. For the 600-1000 Hz band, Omega_GW(f)<0.14*(f/900 Hz)^3, a factor of 2.5 lower than the best previously reported upper limits. We find Omega_GW(f)<1.8x10^-4 using a spectral index of zero for 170-600 Hz and Omega_GW(f)<1.0*(f/1300 Hz)^3 for 1000-1726 Hz, bands in which no previous direct limits have been placed. The limits in these four bands are the lowest direct measurements to date on the stochastic background. We discuss the implications of these results in light of the recent claim by the BICEP2 experiment of the possible evidence for inflationary gravitational waves.

The LIGO Scientific Collaboration; the Virgo Collaboration; J. Aasi; B. P. Abbott; R. Abbott; T. Abbott; M. R. Abernathy; T. Accadia; F. Acernese; K. Ackley; C. Adams; T. Adams; P. Addesso; R. X. Adhikari; C. Affeldt; M. Agathos; N. Aggarwal; O. D. Aguiar; A. Ain; P. Ajith; A. Alemic; B. Allen; A. Allocca; D. Amariutei; M. Andersen; R. Anderson; S. B. Anderson; W. G. Anderson; K. Arai; M. C. Araya; C. Arceneaux; J. Areeda; S. M. Aston; P. Astone; P. Aufmuth; C. Aulbert; L. Austin; B. E. Aylott; S. Babak; P. T. Baker; G. Ballardin; S. W. Ballmer; J. C. Barayoga; M. Barbet; B. C. Barish; D. Barker; F. Barone; B. Barr; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; A. Basti; J. C. Batch; J. Bauchrowitz; Th. S. Bauer; B. Behnke; M. Bejger; M. G. Beker; C. Belczynski; A. S. Bell; C. Bell; G. Bergmann; D. Bersanetti; A. Bertolini; J. Betzwieser; P. T. Beyersdorf; I. A. Bilenko; G. Billingsley; J. Birch; S. Biscans; M. Bitossi; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; S. Bloemen; M. Blom; O. Bock; T. P. Bodiya; M. Boer; G. Bogaert; C. Bogan; C. Bond; F. Bondu; L. Bonelli; R. Bonnand; R. Bork; M. Born; V. Boschi; Sukanta Bose; L. Bosi; C. Bradaschia; P. R. Brady; V. B. Braginsky; M. Branchesi; J. E. Brau; T. Briant; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; A. F. Brooks; D. A. Brown; D. D. Brown; F. Brückner; S. Buchman; T. Bulik; H. J. Bulten; A. Buonanno; R. Burman; D. Buskulic; C. Buy; L. Cadonati; G. Cagnoli; J. Calderón Bustillo; E. Calloni; J. B. Camp; P. Campsie; K. C. Cannon; B. Canuel; J. Cao; C. D. Capano; F. Carbognani; L. Carbone; S. Caride; A. Castiglia; S. Caudill; M. Cavaglià; F. Cavalier; R. Cavalieri; C. Celerier; G. Cella; C. Cepeda; E. Cesarini; R. Chakraborty; T. Chalermsongsak; S. J. Chamberlin; S. Chao; P. Charlton; E. Chassande-Mottin; X. Chen; Y. Chen; A. Chincarini; A. Chiummo; H. S. Cho; J. Chow; N. Christensen; Q. Chu; S. S. Y. Chua; S. Chung; G. Ciani; F. Clara; J. A. Clark; F. Cleva; E. Coccia; P. -F. Cohadon; A. Colla; C. Collette; M. Colombini; L. Cominsky; M. Constancio Jr.; A. Conte; D. Cook; T. R. Corbitt; M. Cordier; N. Cornish; A. Corpuz; A. Corsi; C. A. Costa; M. W. Coughlin; S. Coughlin; J. -P. Coulon; S. Countryman; P. Couvares; D. M. Coward; M. Cowart; D. C. Coyne; R. Coyne; K. Craig; J. D. E. Creighton; S. G. Crowder; A. Cumming; L. Cunningham; E. Cuoco; K. Dahl; T. Dal Canton; M. Damjanic; S. L. Danilishin; S. D'Antonio; K. Danzmann; V. Dattilo; H. Daveloza; M. Davier; G. S. Davies; E. J. Daw; R. Day; T. Dayanga; G. Debreczeni; J. Degallaix; S. Deléglise; W. Del Pozzo; T. Denker; T. Dent; H. Dereli; V. Dergachev; R. De Rosa; R. T. DeRosa; R. DeSalvo; S. Dhurandhar; M. Díaz; L. Di Fiore; A. Di Lieto; I. Di Palma; A. Di Virgilio; A. Donath; F. Donovan; K. L. Dooley; S. Doravari; S. Dossa; R. Douglas; T. P. Downes; M. Drago; R. W. P. Drever; J. C. Driggers; Z. Du; S. Dwyer; T. Eberle; T. Edo; M. Edwards; A. Effler; H. Eggenstein; P. Ehrens; J. Eichholz; S. S. Eikenberry; G. Endr?czi; R. Essick; T. Etzel; M. Evans; T. Evans; M. Factourovich; V. Fafone; S. Fairhurst; Q. Fang; S. Farinon; B. Farr; W. M. Farr; M. Favata; H. Fehrmann; M. M. Fejer; D. Feldbaum; F. Feroz; I. Ferrante; F. Ferrini; F. Fidecaro; L. S. Finn; I. Fiori; R. P. Fisher; R. Flaminio; J. -D. Fournier; S. Franco; S. Frasca; F. Frasconi; M. Frede; Z. Frei; A. Freise; R. Frey; T. T. Fricke; P. Fritschel; V. V. Frolov; P. Fulda; M. Fyffe; J. Gair; L. Gammaitoni; S. Gaonkar; F. Garufi; N. Gehrels; G. Gemme; E. Genin; A. Gennai; S. Ghosh; J. A. Giaime; K. D. Giardina; A. Giazotto; C. Gill; J. Gleason; E. Goetz; R. Goetz; L. Gondan; G. González; N. Gordon; M. L. Gorodetsky; S. Gossan; S. Goßler; R. Gouaty; C. Gräf; P. B. Graff; M. Granata; A. Grant; S. Gras; C. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; P. Groot; H. Grote; K. Grover; S. Grunewald; G. M. Guidi; C. Guido; K. Gushwa; E. K. Gustafson; R. Gustafson; D. Hammer; G. Hammond; M. Hanke; J. Hanks; C. Hanna; J. Hanson; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; M. Hart; M. T. Hartman; C. -J. Haster; K. Haughian; A. Heidmann; M. Heintze; H. Heitmann; P. Hello; G. Hemming; M. Hendry; I. S. Heng; A. W. Heptonstall; M. Heurs; M. Hewitson; S. Hild; D. Hoak; K. A. Hodge; K. Holt; S. Hooper; P. Hopkins; D. J. Hosken; J. Hough; E. J. Howell; Y. Hu; E. Huerta; B. Hughey; S. Husa; S. H. Huttner; M. Huynh; T. Huynh-Dinh; D. R. Ingram; R. Inta; T. Isogai; A. Ivanov; B. R. Iyer; K. Izumi; M. Jacobson; E. James; H. Jang; P. Jaranowski; Y. Ji; F. Jiménez-Forteza; W. W. Johnson; D. I. Jones; R. Jones; R. J. G. Jonker; L. Ju; Haris K; P. Kalmus; V. Kalogera; S. Kandhasamy; G. Kang; J. B. Kanner; J. Karlen; M. Kasprzack; E. Katsavounidis; W. Katzman; H. Kaufer; K. Kawabe; F. Kawazoe; F. Kéfélian; G. M. Keiser; D. Keitel; D. B. Kelley; W. Kells; A. Khalaidovski; F. Y. Khalili

2014-06-17T23:59:59.000Z

477

Evaluation of Background Concentrations of Contaminants in an Unusual Desert Arroyo Near a Uranium Mill Tailings Disposal Cell - 12260  

SciTech Connect

The U.S. Department of Energy (DOE) Office of Legacy Management (LM) manages 27 sites that have groundwater containing uranium concentrations above background levels. The distal portions of the plumes merge into background groundwater that can have 50 ?g/L or more uranium. Distinguishing background from site-related uranium is often problematic, but it is critical to determining if remediation is warranted, establishing appropriate remediation goals, and evaluating disposal cell performance. In particular, groundwater at disposal cells located on the upper Cretaceous Mancos Shale may have relatively high background concentrations of uranium. Elevated concentrations of nitrate, selenium, and sulfate accompany the uranium. LM used geologic analogs and uranium isotopic signatures to distinguish background groundwater from groundwater contaminated by a former uranium processing site. The same suite of contaminants is present in groundwater near former uranium processing sites and in groundwater seeps emanating from the Mancos Shale over a broad area. The concentrations of these contaminants in Many Devils Wash, located near LM's Shiprock disposal cell, are similar to those in samples collected from many Mancos seeps, including two analog sites that are 8 to 11 km from the disposal cell. Samples collected from Many Devils Wash and the analog sites have high AR values (about 2.0)-in contrast, groundwater samples collected near the tailings disposal cell have AR values near 1.0. These chemical signatures raise questions about the origin of the contamination seeping into Many Devils Wash. (authors)

Bush, Richard P. [U.S. Department of Energy Office of Legacy Management (United States); Morrison, Stan J. [S.M. Stoller Corporation (United States)

2012-07-01T23:59:59.000Z

478

HerMES: COSMIC INFRARED BACKGROUND ANISOTROPIES AND THE CLUSTERING OF DUSTY STAR-FORMING GALAXIES  

SciTech Connect

We present measurements of the auto- and cross-frequency power spectra of the cosmic infrared background (CIB) at 250, 350, and 500 {mu}m (1200, 860, and 600 GHz) from observations totaling {approx}70 deg{sup 2} made with the SPIRE instrument aboard the Herschel Space Observatory. We measure a fractional anisotropy {delta}I/I = 14% {+-} 4%, detecting signatures arising from the clustering of dusty star-forming galaxies in both the linear (2-halo) and nonlinear (1-halo) regimes; and that the transition from the 2- to 1-halo terms, below which power originates predominantly from multiple galaxies within dark matter halos, occurs at k{sub {theta}} {approx} 0.10-0.12 arcmin{sup -1} (l {approx} 2160-2380), from 250 to 500 {mu}m. New to this paper is clear evidence of a dependence of the Poisson and 1-halo power on the flux-cut level of masked sources-suggesting that some fraction of the more luminous sources occupy more massive halos as satellites, or are possibly close pairs. We measure the cross-correlation power spectra between bands, finding that bands which are farthest apart are the least correlated, as well as hints of a reduction in the correlation between bands when resolved sources are more aggressively masked. In the second part of the paper, we attempt to interpret the measurements in the framework of the halo model. With the aim of fitting simultaneously with one model the power spectra, number counts, and absolute CIB level in all bands, we find that this is achievable by invoking a luminosity-mass relationship, such that the luminosity-to-mass ratio peaks at a particular halo mass scale and declines toward lower and higher mass halos. Our best-fit model finds that the halo mass which is most efficient at hosting star formation in the redshift range of peak star-forming activity, z {approx} 1-3, is log(M{sub peak}/M{sub Sun }) {approx} 12.1 {+-} 0.5, and that the minimum halo mass to host infrared galaxies is log(M{sub min}/M{sub Sun }) {approx} 10.1 {+-} 0.6.

Viero, M. P.; Zemcov, M.; Bock, J.; Cooray, A.; Dowell, C. D. [California Institute of Technology, 1200 E. California Blvd., Pasadena, CA 91125 (United States); Wang, L. [Institute for Computational Cosmology, Department of Physics, University of Durham, South Road, Durham, DH1 3LE (United Kingdom); Addison, G. [Department of Astrophysics, Denys Wilkinson Building, University of Oxford, Keble Road, Oxford OX1 3RH (United Kingdom); Amblard, A. [NASA, Ames Research Center, Moffett Field, CA 94035 (United States); Arumugam, V. [Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ (United Kingdom); Aussel, H.; Bethermin, M. [Laboratoire AIM-Paris-Saclay, CEA/DSM/Irfu - CNRS - Universite Paris Diderot, CE-Saclay, pt courrier 131, F-91191 Gif-sur-Yvette (France); Boselli, A.; Buat, V.; Burgarella, D. [Laboratoire d'Astrophysique de Marseille - LAM, Universite d'Aix-Marseille and CNRS, UMR7326, 38 rue F. Joliot-Curie, F-13388 Marseille Cedex 13 (France); Casey, C. M. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Clements, D. L. [Astrophysics Group, Imperial College London, Blackett Laboratory, Prince Consort Road, London SW7 2AZ (United Kingdom); Conley, A. [Center for Astrophysics and Space Astronomy 389-UCB, University of Colorado, Boulder, CO 80309 (United States); Conversi, L. [Herschel Science Centre, European Space Astronomy Centre, Villanueva de la Canada, E-28691 Madrid (Spain); De Zotti, G. [INAF - Osservatorio Astronomico di Padova, Vicolo dell'Osservatorio 5, I-35122 Padova (Italy); Farrah, D., E-mail: marco.viero@caltech.edu [Astronomy Centre, Dept. of Physics and Astronomy, University of Sussex, Brighton BN1 9QH (United Kingdom); and others

2013-07-20T23:59:59.000Z

479

Upper limits on a stochastic gravitational-wave background using LIGO and Virgo interferometers at 600–1000 Hz  

Science Journals Connector (OSTI)

A stochastic background of gravitational waves is expected to arise from a superposition of many incoherent sources of gravitational waves, of either cosmological or astrophysical origin. This background is a target for the current generation of ground-based detectors. In this article we present the first joint search for a stochastic background using data from the LIGO and Virgo interferometers. In a frequency band of 600–1000 Hz, we obtained a 95% upper limit on the amplitude of ?GW(f)=?3(f/900??Hz)3, of ?3<0.32, assuming a value of the Hubble parameter of h100=0.71. These new limits are a factor of seven better than the previous best in this frequency band.

J. Abadie et al. (LIGO Scientific Collaboration; Virgo Collaboration)

2012-06-04T23:59:59.000Z

480

Becchi-Rouet-Stora-Tyutin quantization of closed type-II superstring in curved background with torsion  

Science Journals Connector (OSTI)

In this paper we work out some aspects of quantization of a closed type-II superstring in a curved background with torsion using the Becchi-Rouet-Stora-Tyutin (BRST) approach. The constraint algebra is shown to be superconformal and then the nilpotency of the BRST approach is shown for both the free and interacting cases. It is found that for the interacting case one has q-number anomalies in addition to c-number anomalies, a result expected from the calculation involving the bosonic string in a curved background by Banks, Nemeshansky, and Sen.

S. Alam

1989-12-15T23:59:59.000Z

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