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Report of Group II-2: Running at ISA

Description: A discussion is given of the anticipated operating conditions at the ISABELLE storage rings. Communications between experimental and control areas are considered, and beam luminosity monitoring is discussed. Running conditions and expected problems are outlined. (PMA)
Date: August 4, 1977
Creator: Chen, M.; Herrera, J. C.; Littenberg, L.; Thorndike, A.; Ogren, H.; Potter, K. et al.
Partner: UNT Libraries Government Documents Department
open access

Reducing radon daughter background in alpha continuous air monitors

Description: Alpha continuous air monitors are instruments designed to sample aerosols which may contain alpha-emitting radionuclides and, in near-real time, to monitor the sample for alpha emissions. This process is subject to interference from radon decay products. The usual method for overcoming this interference is by signal processing or data processing in such a manner as to accurately subtract a portion of the background from the transuranic count. An innovative alternative approach has been jointly … more
Date: January 1, 1991
Creator: Rodgers, J.C. (Los Alamos National Lab., NM (United States)) & McFarland, A.R. (Texas A and M Univ., College Station, TX (United States). Dept. of Mechanical Engineering)
Partner: UNT Libraries Government Documents Department
open access

Low-background measurements of neutron emission from Ti metal in pressurized deuterium gas

Description: A wide variety of neutron detector systems have been used at various research facilities to search for anomalous neutron emission from deuterated metals. Some of these detector systems are summarized here together with possible sources of spurious signals from electronic noise. During the past two years, we have performed experiments to measure neutron emission from pressurized D{sub 2} gas mixed with various forms of titanium metal chips and sponge. Details concerning the neutron detectors, ex… more
Date: January 1, 1991
Creator: Menlove, H. O.; Paciotti, M. A.; Claytor, T. N. & Tuggle, D. G.
Partner: UNT Libraries Government Documents Department
open access

Si(Li)-NaI(Tl) sandwich detector array for measurements of trace radionuclides in soil samples

Description: An ultra-sensitive x-/..gamma..-ray detector system for assaying trace radioactivity in actinide contaminated soil and ash samples has been developed. The new system consists of an array of 6 large Si(Li) x-ray detectors sensitive on both faces and mounted on edge in a paddle-shaped cryostat with a 14 cm dia Be window on each side. The paddle, with a sample of the soil placed at each window, is sandwiched between 2 large NaI(Tl) scintillators which suppress the ..gamma.. background. With x rays… more
Date: January 1, 1985
Creator: Strauss, M. G.; Sherman, I. S.; Roche, C. T. & Pehl, R. H.
Partner: UNT Libraries Government Documents Department
open access

Spectrum of the microwave background radiation

Description: A review is given of the present status of measurements of the spectrum of the microwave background. Factors which limit experimental accuracy are discussed with particular reference to high frequency measurements. A selection of the available measurements yields a data set which is reasonably consistent with the blackbody spectrum for a temperature of 2.9 K. A simple statistical analysis suggests either that there are errors in the data set, or that deviations from a blackbody spectrum exist. … more
Date: April 1, 1982
Creator: Richards, P.L.
Partner: UNT Libraries Government Documents Department
open access

The excess flux in the cosmic submillimeter background radiation and the primordial deuterium abundance

Description: Recent measurements of the cosmic background radiation (CBR) show an enhanced flux in the submillimeter regime, compared to the spectrum of a 2.7 K blackbody. Thermal Comptonization of the relic radiation by a hot nonrelativistic plasma has long been known to produce distortions in the CBR spectrum, similar to what has now been observed. Heating of the primeval plasma to temperatures T {approximately} 10{sup 6} {minus} 10{sup 8} K could result from the injection of subcosmic ray protons at epoc… more
Date: October 27, 1989
Creator: Dermer, C. D.; Guessoum, N. (Lawrence Livermore National Lab., CA (USA) & National Aeronautics and Space Administration, Greenbelt, MD (USA). Lab. for High Energy Astrophysics)
Partner: UNT Libraries Government Documents Department
open access

Computational astrophysics relating to the interstellar medium: problems and prospects for the 1980's

Description: The general goal of research on the interstellar medium is to understand the structure and dynamics of the interstellar gas. This subject is important for three reasons. First, the classic tracers of the spiral structure of galaxies are related directly to the gaseous component of galactic disks. Therefore an understanding of the dynamics of the gas is essential in interpreting observations of spiral galaxies. Second, radio continuum observations relate to the magnetic field, which is frozen in… more
Date: May 1, 1980
Creator: Woodward, P.R.
Partner: UNT Libraries Government Documents Department
open access

Neutron-antineutron experiment at Los Alamos Omega West Reactor

Description: The experimental setup is described in detail, and a summary of the characteristics and sensitivities of n-anti n conversion experiments running, under construction, and proposed is given. (WHK)
Date: January 1, 1982
Creator: Anderson, H.L.
Partner: UNT Libraries Government Documents Department
open access

New scheme for the design and operation of proton--proton storage accelerators

Description: A new system is presented for storage accelerating rings which allows many options for operation. During injection, acceleration, and collision, the beams are maintained in the form of azimuthally long bunches. Current is built up in a low-energy, small circumference accumulator ring. Injection into the storage accelerators is carried out with the bunches phased so that they do not collide. The rf buckets can be matched to the incoming long bunches with only a small dilution. Operation of the s… more
Date: January 1, 1977
Creator: Claus, J.; Herrera, J.; Humphrey, J.; Marx, M. & Month, M.
Partner: UNT Libraries Government Documents Department
open access

Detectors for high energy nuclear collisions: problems, progress and promise

Description: Some perspective of the main issues in high energy nuclear collision physics is offered. How to identify and measure a quark-gluon plasma is considered to still be an open question. The types of detector configurations to be used in high-energy nucleus-nucleus experiments are discussed. Particular issues covered are measurements of lepton pair spectra, tracking systems and multitrack resolution, event-rate capabilities, backgrounds and other problems close to the beam, and calorimetry. 2 refs. … more
Date: January 1, 1986
Creator: Ludlam, T.W.
Partner: UNT Libraries Government Documents Department
open access

New advanced in alpha spectrometry by liquid scintillation methods

Description: Although the ability to count alpha particles by liquid scintillation methods has been long recognized, limited use has been made of the method because of problems of high background and alpha energy identification. In recent years some new developments in methods of introducing the alpha-emitting nuclide to the scintillator, in detector construction, and in electronics for processing the energy analog and time analog signals from the detector have allowed significant alleviation of the problem… more
Date: January 1, 1979
Creator: McDowell, W.J. & Case, G.N.
Partner: UNT Libraries Government Documents Department
open access

Boltzmann babies in the proper time measure

Description: After commenting briefly on the role of the typicality assumption in science, we advocate a phenomenological approach to the cosmological measure problem. Like any other theory, a measure should be simple, general, well defined, and consistent with observation. This allows us to proceed by elimination. As an example, we consider the proper time cutoff on a geodesic congruence. It predicts that typical observers are quantum fluctuations in the early universe, or Boltzmann babies. We sharpen this… more
Date: December 20, 2007
Creator: Bousso, Raphael; Bousso, Raphael; Freivogel, Ben & Yang, I-Sheng
Partner: UNT Libraries Government Documents Department
open access

Correlation of the highest energy cosmic rays with nearby extragalactic objects

Description: Using data collected at the Pierre Auger Observatory during the past 3.7 years, we demonstrate that there is a correlation between the arrival directions of cosmic rays with energy above {approx} 6 x 10{sup 19} eV and the positions of active galactic nuclei (AGN) lying within {approx} 75 Mpc. We reject the hypothesis of an isotropic distribution of these cosmic rays at over 99% confidence level from a prescribed a priori test. The correlation we observe is compatible with the hypothesis that th… more
Date: November 1, 2007
Creator: Abraham, J.; Abreu, P.; Aglietta, M.; Aguirre, C.; Allard, D.; Allekotte, I. et al.
Partner: UNT Libraries Government Documents Department
open access

3 mm Anisotropy Measurement: On the Quadrupole Component in theCosmic Background Radiation

Description: We have mapped the large-scale anisotropy in the cosmic background radiation at 3 mm wavelength using a liquid-helium-cooled balloon-borne radiometer sensitive enough to detect the dipole in one gondola rotation (1 minute). Statistical errors on the dipole and quadrupole components are below 0.1 mK with less than 0.1 m K galactic contribution. We find a dipole consistent with previous measurements but disagree with recent quadrupole reports. The measurement is also useful in searching for spect… more
Date: November 1, 1982
Creator: Lubin, Philip M.; Epstein, Gerald L. & Smoot, George F.
Partner: UNT Libraries Government Documents Department
open access

Correlation of the highest-energy cosmic rays with the positions of nearby active galactic nuclei

Description: Data collected by the Pierre Auger Observatory provide evidence for anisotropy in the arrival directions of the cosmic rays with the highest energies, which are correlated with the positions of relatively nearby active galactic nuclei (AGN) [1]. The correlation has maximum significance for cosmic rays with energy greater than {approx} 6 x 10{sup 19} eV and AGN at a distance less than {approx} 75 Mpc. We have confirmed the anisotropy at a confidence level of more than 99% through a test with par… more
Date: December 1, 2007
Creator: Collaboration, The Pierre auger
Partner: UNT Libraries Government Documents Department
open access

Evaluation of radioactive background rejection in 76Ge neutrino-lessdouble-beta decay experiments using a highly segmented HPGe detector

Description: A highly segmented coaxial HPGe detector was operated in a low background counting facility for over 1 year to experimentally evaluate possible segmentation strategies for the proposed Majorana neutrino-less double-beta decay experiment. Segmentation schemes were evaluated on their ability to reject multi-segment events while retaining single-segment events. To quantify a segmentation scheme's acceptance efficiency the percentage of peak area due to single segment events was calculated for peak… more
Date: February 5, 2007
Creator: Chan, Yuen-Dat; Campbell, D. B.; Vetter, K.; Henning, R.; Lesko, K.; Chan, Y. D. et al.
Partner: UNT Libraries Government Documents Department
open access

OPTIMIZING RADIOLOGICAL MONITOR SITING OVER THE CONTINENTAL U.S.

Description: The US Environmental Protection Agency (EPA) is installing a network of sensors in the US to monitor background radiation and elevated radiation levels expected from a possible nuclear incident. The network (RadNet) of 180 fixed sensors is intended to provide a basic estimate of the radiation level throughout the US and enhanced accuracy near population centers. This report discusses one of the objective methods for locating these monitors based on criteria outlined by the EPA. The analysis emp… more
Date: October 29, 2007
Creator: Chen, K; Robert Buckley, R; Robert Kurzeja, R; Lance Osteen, L & Saleem Salaymeh, S
Partner: UNT Libraries Government Documents Department
open access

Cosmic microwave background: present status and future prospects. [Review]

Description: After a brief review of the origin of the radiation according to the standard model, the status of present measurements of the spectrum and the large-scale isotropy is discussed. Finally, it is indicated what are the prospects for improved measurements in the next decade. 17 references. (JFP)
Date: December 1, 1978
Creator: Muller, R.A.
Partner: UNT Libraries Government Documents Department
open access

Surface radiation survey and soil sampling of the 300-FF-1 operable unit, Hanford Site, southeastern Washington: A case study

Description: The methods used for conducting a radiological characterization of the soil surface for the Phase I Remedial Investigation of a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) site is presented via a case study. The study site is an operable unit (300-FF-1) located in and adjacent to the 300 Area of the US Department of Energy's Hanford Site in southeastern Washington State. The operable unit contains liquid and solid waste disposal facilities associated with nucl… more
Date: October 1, 1990
Creator: Teel, S. S. & Olsen, K. B.
Partner: UNT Libraries Government Documents Department
open access

Low-level gamma-ray spectrometry

Description: Low-level gamma-ray spectrometry generally equates to high-sensitivity gamma-ray spectrometry that can be attained by background reduction, selective signal identification, or some combination of both. Various methods for selectively identifying gamma-ray events and for reducing the background in gamma-ray spectrometers are given. The relative magnitude of each effect on overall sensitivity and the relative cost'' for implementing them are given so that a cost/benefit comparison can be made and… more
Date: October 1, 1990
Creator: Brodzinski, R.L.
Partner: UNT Libraries Government Documents Department
open access

Dosimetry of x-ray beams: The measure of the problem

Description: This document contains the text of an oral presentation on dosimetry of analytical x-ray equipment presented at the Denver X-Ray Conference. Included are discussions of sources of background radiation, exposure limits from occupational sources, and the relationship of these sources to the high dose source of x-rays found in analytical machines. The mathematical basis of x-ray dosimetry is reviewed in preparation for more detailed notes on personnel dosimetry and the selection of the most approp… more
Date: August 1, 1986
Creator: de Castro, T.M.
Partner: UNT Libraries Government Documents Department
open access

Transverse momentum signatures for heavy Higgs bosons

Description: Heavy Higgs bosons produced by WW fusion at the SSC will have transverse mementum of order M/sub w/. The background due to q anti q ..-->.. ZZ will produce pairs with characteristically less transverse momentum. This provides a useful discriminator. It may be possible to tag the WW fusion events in a manner analogous to that used in two photon physics. 12 refs., 4 figs.
Date: January 1, 1986
Creator: Cahn, R. N.; Ellis, S. D.; Kleiss, R. & Stirling, W. J.
Partner: UNT Libraries Government Documents Department
open access

Recent experience with backgrounds at the SLC

Description: During the 1990 SLC/Mark II runs, machine backgrounds visible in the new vertex detectors were studied. These detectors had active elements at radii from 3 to 17 cm and were subjected to backgrounds unique to linear colliders. We describe recent progress in identifying sources and developing control techniques. 4 refs., 3 figs.
Date: May 1, 1991
Creator: Jacobsen, R.; Band, H.; Barklow, T.; Bazarko, A.; Brown, K.; Burke, D. et al.
Partner: UNT Libraries Government Documents Department
open access

Analysis of soil samples from OMRE decommissioning project

Description: In order to establish that the present Organic Moderated Reactor Experiment (OMRE) site does not exceed the criteria for radioactive contamination, samples obtained from the remainder of the facility that was not removed such as soil, concrete pads, various structural materials, and the leach pond area were analyzed to determine their radioactive content. The results of the analyses performed on soil samples are presented. Results of this study indicate that the activity at the OMRE decommissio… more
Date: January 1, 1979
Creator: Simpson, O.D.; Chapin, J.A.; Hine, R.E.; Mandler, J.W.; Orme, M.P. & Soli, G.A.
Partner: UNT Libraries Government Documents Department
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