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in subjects: "Cosmic Radiation"

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Pseudorapidity distributions and correlations in central sup 16 O interactions at 200 A GeV

Whether or not adequate energy densities for a transition to the Quark-Gluon Plasma (QGP) phase are possible in {sup 16}O and {sup 32}S induced reactions is still an open question. Before unambiguous signals can be identified it is necessary to understand the background upon which the expected QGP signatures can be sought. An important aim of early experiments in this new energy density regime is thus to understand the process of hadronization in a nuclear environment. In any discussion of high… more

Date: January 1, 1988

Creator: Wilkes, R. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Products from cosmic-ray interactions in extraterrestrial matter: What they tell us about radiation backgrounds in space

The nuclides and the heavy-nuclei ''tracks'' made by the interactions of solar and galactic cosmic-ray particles with meteorites, lunar samples, and the Earth have been extensively studied, simulated, and modelled. Most research involves the use of these cosmogenic products to study the history of the ''targets'' or of the cosmic rays. However, much work has also been done in understanding these interactions and in predicting their rates as a function of the target's size and shape and of the l… more

Date: January 1, 1987

Creator: Reedy, R. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Gamma rays from Cygnus X-1: Modeling and nonthermal pair production

The gamma-ray bump observed between 0.5 and 2 MeV in the spectrum of Cygnus X-1 can be interpreted as the thermal emissions from a hot (kT)approximately)400 keV) pair-dominated cloud. We argue that the X-rays and gamma rays are produced in separate emission regions, and calculate the photon-photon pair production rate from X-ray and gamma-ray interactions in the vicinity of Cyg X-1 by employing a simplified geometry for the two emitting regions.

Date: February 1, 1988

Creator: Dermer, C. D. & Liang, E. P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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JACEE long duration balloon flights

JACEE balloon-borne emulsion chamber detectors are used to observe the spectra and interactions of cosmic ray protons and nuclei in the energy range 1-100A TeV. Experience with long duration mid-latitude balloon flights and characteristics of the detector system that make it ideal for planned Antarctic balloon flights are discussed. 5 refs., 2 figs.

Date: January 1, 1989

Creator: Burnett, T.; Iwai, J.; Lord, J.J.; Strausz, S.; Wilkes, R.J. (Washington Univ., Seattle, WA (USA)); Dake, S. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Pseudorapidity densities and fluctuations in central sup 32 S interactions at 200A GeV

Observations of heavy ion interactions at the highest available accelerator energies provide essential information for the analysis and interpretation of cosmic ray interactions. We report on an experiment in which emulsion chamber detectors were exposed to beams of 200A GeV {sup 32}S ions at the CERN SPS. We present statistical features of pseudorapidity distributions from central collisions in the experimental sample and compare them with the predictions from the Lund Model (FRITIOF) which co… more

Date: January 1, 1990

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Particle correlations in JACEE (Japanese-American Cooperative Emulsion Experiment) nucleus-nucleus collisions

Correlations in the production of charged particles and photons can be examined in detail in the central and forward rapidity range using high multiplicity ({ge}100 charged tracks) events from JACEE emulsion chambers. Results are presented on several forms of correlations studies. 9 refs., 2 figs.

Date: January 1, 1990

Item Type: Article

Partner: UNT Libraries Government Documents Department

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A proposal for a precision test of the standard model by neutrino-electron scattering (Large /hacek C/erenkov Detector Project)

A precision measurement of neutrino-electron elastic scattering from a beam stop neutrino source at LAMPF is proposed. The total error in sin/sup 2/theta/sub W/ is estimated to be +-0.89/percent/. The experiment also will be sensitive to neutrino oscillations and supernova-neutrino bursts, and should set improved limits on the neutrino-charge radius and magnetic-dipole moment. The detector consists of a 2.5-million-gallon tank of water with approximately 14,000 photomultiplier tubes lining the … more

Date: April 1, 1988

Creator: Allen, R. C.; Lu, X.-Q.; Gollwitzer, K.; Igo, G. J.; Gulmez, E.; Whitten, C. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Cosmic ray half life of sup 54 Mn

A search for the {beta}{sup +} decay of {sup 54}Mn has established an upper limit of 4.4 {times} 10{sup {minus}8} for this branching ratio, and a lower limit of 13.3 for the log ft value for this second forbidden unique transition. Assuming that the {beta}{sup {minus}} decay branch has the same log ft value, then its partial half life must be greater than 4 {times} 10{sup 4} years. Experiments to directly measure the {beta}{sup {minus}} decay rate of {sup 54}Mn are now in progress. 6 refs., 2 f… more

Date: August 1, 1989

Creator: Norman, E.B.; Sur, B.; Vogel, K.R.; Lesko, K.T.; Larimer, R.M. & Browne, E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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The digital data acquisition chain and the cosmic ray trigger system for the SLD Warm Iron Calorimeter

The entire data-acquisition chain, from the custom-made front-end electronics to the Fastbus readout and data-reduction module, for the digital readout of the SLD limited streamer tube Warm Iron Calorimeter and Muon Identifier is described. Also described is a Fastbus Cosmic Logic Unit being developed to achieve the capability of reading cosmic ray events, also during the inter-crossing time, for apparatus monitoring and calibration purposes. 9 refs., 9 figs.

Date: August 1, 1989

Creator: Benvenuti, A.; Piemontese, L.; Calcaterra, A.; De Sangro, R.; De Simone, P.; Burrows, P. N. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Status of the expansion of the CYGNUS array at Los Alamos

The CYGNUS air shower array, located in Los Alamos, New Mexico, has been operating since April, 1986. The expansion of the array from 108 to 200 counters is described along with the increase in muon detection area. The new array, to be fully operational by the end of 1989, will have three times the sensitivity to UHE sources. 5 refs., 2 figs.

Date: January 1, 1989

Creator: Berley, D.; Chang, C. Y.; Dingus, B. L.; Goodman, J. A.; Haines, T. J.; Stark, M. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Silver isotopic anomalies in iron meteorites: cosmic-ray production and other possible sources

The sources of excess /sup 107/Ag observed in iron meteorites by Kaiser, Kelly, and Wasserburg (1980) are examined, with emphasis on the reactions of cosmic-ray particles with palladium. The cross sections for the production of the silver isotopes from palladium by energetic cosmic-ray particles are evaluated or estimated and used to calculate spallogenic production rates relative to that of /sup 53/Mn from iron. The upper limit for the production rate of excess /sup 107/Ag by galactic-cosmic-r… more

Date: April 18, 1980

Creator: Reedy, R. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Spectrum of the microwave background radiation

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.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Research in nuclear astrophysics: Stellar collapse and supernovae

This progress report describes the nuclear astrophysics research activities in the Earth and Space Sciences Department at Stony Brook during the last year. Our research focused on three aspects of nuclear astrophysics: (1) the equation of state of hot, dense matter, (2) the origin of supernovae and neutron stars, (3) the early cooling epoch of neutron stars. The following contains detailed reports which summarize each completed project.

Date: January 1, 1992

Creator: Lattimer, J.M. & Yahil, A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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CYGNUS Collaboration contributions to the twenty-second ICRC

This report contains short papers on the cygnus experiments on the detection of cosmic air showers from distant sources such as nebulae, galaxies, x-ray sources, etc. (LSP).

Date: August 1, 1991

Creator: Alexandreas, D. E.; Biller, S.; Dion, G. M.; Lu, X. Q.; Yodh, G. B.; Berley, D. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

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

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)

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Cosmic ray events in Soudan 2

The Soudan 2 detector is located at a depth of 2090 meters-water equivalent (mwe). About 2 million muon events have been recorded. Here we report on our plans to analyze them for comparison with expectations from atmospheric cosmic ray models. Plans and capabilities to analyze multiple muons and monopoles are also discussed. 3 refs., 5 figs.

Date: August 23, 1989

Creator: Allison, W. W. M.; Alner, G. J.; Ambats, I.; Ayres, D.; Balka, L.; Barr, G. D. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Studies of. mu. prime s underground with the Soudan 2 Tracker

During the period July 1987 through March 1988, a section of the Soudan 2 active shield known as the Tracker' recorded {approximately}250,000 muon tracks. The detector is located in the Tower-Soudan State Park in Soudan, Minnesota USA at a depth of 2090 meters-water equivalent. We have analysed the data collected and searched for time-dependent astronomical sources. Distributions in azimuthal and zenith angles as well as declination and right ascension are shown. 1 ref., 7 figs., 1 tab.

Date: August 23, 1989

Creator: Kochocki, J.; Benjamin, D.; Ewen, B.; Kafka, T.; Mann, A.; McMaster, L. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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A database of fragmentation cross section measurements applicable to cosmic ray propagation calculations

A database of single particle inclusive fragment production cross section measurements has been established and is accessible over common computer networks. These measurements have been obtained from both published literature and direct communication with experimenters and include cross sections for nuclear beams on H, He, and heavier targets, and for H and He beams on nuclear targets, for energies >30 MeV/nucleon. These cross sections are directly applicable to calculations involving cosmic ra… more

Date: August 1, 1989

Creator: Crawford, H. J.; Engelage, J.; Jones, F. C.; Guzik, T. G.; Mitchell, J. W.; Wefel, J. P. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Comment on an unusual event in the E594 detector from the direction of Cygnus X-3

A small array located near the 80 m/sup 2/ E594 neutrino detector at Fermilab had a two week run. The author makes two comments related to ultra high energy gamma ray physics. The first regards the question of angular resolution from muons. In general, the angle of a muon will not reflect the angle of the shower for reasons which include transverse momentum at production, multiple scattering in the atmosphere, multiple scattering in the detector and detector angular resolution. In multiple muon… more

Date: January 1, 1985

Creator: Goodman, M.C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Relating space radiation environments to risk estimates

This lecture will provide a bridge from the physical energy or LET spectra as might be calculated in an organ to the risk of carcinogenesis, a particular concern for extended missions to the moon or beyond to Mars. Topics covered will include (1) LET spectra expected from galactic cosmic rays, (2) probabilities that individual cell nuclei in the body will be hit by heavy galactic cosmic ray particles, (3) the conventional methods of calculating risks from a mixed environment of high and low LET… more

Date: October 1, 1991

Creator: Curtis, S.B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Soudan 2 nucleon decay experiment

The Soudan 2 nucleon decay experiment consists of a 1.1 Kton fine grained iron tracking calorimeter. It has a very isotropic detection structure which along with its flexible trigger will allow detection of multiparticle and neutrino proton decay modes. The detector has now entered its construction stage.

Date: January 1, 1986

Creator: Thron, J. L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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High energy neutrinos from Cyg X-3

Assuming that the UHE air showers from Cyg X-3 are produced by photons, we calculate the expected neutrino emission from a model which produces the ..gamma..-rays in the atmosphere of the Cyg X-3 companion. We discuss the possibility of detecting such neutrinos in underground detectors and the constraints that such a signal places on the use of this model in other particle production scenarios. 16 refs., 5 figs.

Date: July 1, 1985

Creator: Walker, T. P.; Kolb, E. W. & Turner, M. S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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The neutrino program at LAMPF

There are two neutrino experiments that this paper discusses: the first experiment is designed to verify the interference between charged and neutral current amplitudes in {nu}{sub e}- e scattering. The experiment is situated at 90{degree} to the beam stop, and detected recoil electrons from neutrino electron scattering. The experiment is sensitive to recoil electrons from {nu}{sub {mu}}, {nu}{sub e}, {bar {nu}}{sub {mu}} but the cross section for {nu}{sub e} - e scattering is the dominant cont… more

Date: January 1, 1989

Creator: White, D. Hywel

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Underground muon observations in the Soudan 2 detector

The Soudan 2 nucleon decay detector has recorded data since Summer 1988 using a quarter (dimensions 4 m by 8 m by 5 m high) of the eventual detector. This iron-argon time projection chamber records extensive data on each event and has excellent angular and multi-track resolution. We describe the trigger, the event analysis procedure and the current status of the detector and the underground muon data sample. 1 ref.

Date: September 11, 1989

Creator: Allison, W. W. M.; Barr, G. D.; Brooks, C. B.; Cobb, J. H.; Kirby-Gallagher, L. M.; Giles, R. H. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department