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in subjects: "Cosmic Ray Detection"

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Nucleon decay in Soudan 2.

The Soudan 2 detector is used to search for evidence of nucleon decay. Particular emphasis is put on searches for modes with multiple-charged particles in the final state, and for modes suggested by super-symmetric theories.

Date: June 22, 1999

Creator: Goodman, M. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Neutrino induced muons in Soudan 2.

The neutrino-induced muon rate underground has been measured at Soudan 2. To discriminate from the intense background of atmospheric muons we consider only the through-going muons which originate from horizontal direction ({minus}0.14 < cos{theta} < 0.14). We calculate the horizontal, neutrino-induced muon rate at Soudan 2 from an exposure of 1.23 x 10{sup 8} s as {Phi}{sub {nu}{mu}} = (3.45 {+-} 0.52 {+-} 0.61) x 10{sup {minus}13} (cm{sup 2} sr s){sup {minus}1}.

Date: June 23, 1999

Creator: DeMuth, D. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Cygnus X-3 revisited: 10 years of muon and radio observations.

The Soudan 2 deep underground tracking calorimeter has recorded cosmic ray muon tracks from the direction of the galactic x-ray binary Cygnus X-3 on most transits during the interval 1989-1998. We analyze these events in the context of previous reports of Cygnus X-3-related muon flux during major radio flares of that source. We find some evidence for excess flux during a small number of transits coincident with major radio flares. We also find an indication that these events maybe distributed a… more

Date: June 23, 1999

Creator: Allison, W. W. M.; Alner, G. J.; Ayres, D. S.; Barrett, W. L.; Bode, C.; Fields, T. H. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Atmospheric neutrinos in Soudan 2.

The value and zenith angle dependence of the atmospheric neutrino flavor ratio is interpreted as evidence for neutrino oscillations. The latest values from the Soudan 2 detector are presented. From 4.2 kt-years fiducial exposure, Soudan 2 measures R = 0.66 {+-} 0.11(stat) + 0.05--0.06(syst). Using a subset of the data with the best angular resolution, they plot the L/E distribution and use this to find the allowed region in oscillation parameter space. Their fit suggests that delta m-squared is… more

Date: June 22, 1999

Creator: Goodman, M. C. & Collaboration, The Soudan 2

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Seasonal variations in Soudan 2.

Seasonal Variations in an underground detector may be a signature for Dark Matter. The Soudan 2 detector searches for nucleon decay and atmospheric neutrinos. The trigger rate is about 0.5 Hertz. It is dominated by approximately equal numbers of atmospheric muons and low level radioactivityy. The muon rate has a seasonal variation of {+-}2%, which is consistent with a similar effect at MACRO. The MACRO effect has been correlated with temperature in the upper atmosphere. Our trigger rate has a s… more

Date: June 23, 1999

Creator: Goodman, M. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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The energy spectrometer for particles (ESP): Instrument description and orbital performance

The ESP detector is functionally described, along with the pertinent orbital and spin properties of the spacecraft that supports it. The phoswiched plastic/BGO scintillators sensor design, electronic implementation, and resulting data types are recounted, and the ground calibration procedures are reported. Several illustrative examples of data are given, including the solar proton event of 29 September 1989, and the nearly periodic episodes of high relativistic electron flux that are associated… more

Date: December 31, 1994

Creator: Meier, M.; Belian, D.; Cayton, T.; Christensen, R.; Garcia, B.; Grace, K. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Cosmic ray sun shadow in Soudan 2 underground muon flux.

The absorption of cosmic rays by the sun produces a shadow at the earth. The angular offset and broadening of the shadow are determined by the magnitude and structure of the interplanetary magnetic field (IPMF) in the inner solar system. The authors report the first measurement of the solar cosmic ray shadow by detection of deep underground muon flux in observations made during the entire ten-year interval 1989 to 1998. The sun shadow varies significantly during this time, with a 3.3{sigma} sha… more

Date: June 23, 1999

Creator: Allison, W. W. M.; Alner, G. J.; Ayres, D. S.; Barrett, W. L.; Bode, C.; Fields, T. H. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Observation of the moon shadow in deep underground muon flux.

A shadow of the moon, with a statistical significance of 5{sigma}, has been observed in the underground muon flux at a depth of 2090 mwe using the Soudan 2 detector. The angular resolution of the detector is well described by a Gaussian with {sigma} {le}0.3{degree}. The position of the shadow confirms the alignment of the detector to better than 0.15{degree}. This alignment has remained stable during 10 years of data taking from 1989 through 1998.

Date: June 22, 1999

Creator: Allison, W. W. M.; Alner, G. J.; Ayres, D. S.; Cobb, J. H.; Fields, T. H.; Goodman, M. C. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Experimental overview of axion searches

Experimental methods to search for the ``invisible axion`` (f{sub a} {much_gt} 250 GeV) are reviewed. The report focuses on the axion-photon coupling, both for laboratory experiments as well as those looking for stellar or cosmologically produced axions. The conclusion is that while the axion-photon mixing in principle would permit laboratory axion searches which are broadband in mass, in fact no such experiment could have the sensitivity to the axion, where m{sub afa} {approx} m{sub {pi}f{pi}}… more

Date: June 28, 1995

Creator: van Bibber, K.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Search for neutrinos from active galactic nuclei in Soudan 2.

Models for AGN neutrino production suggest a measurable muon flux in underground detectors in this paper we comment on neutrino point sources and discuss our methods for determining an upper limit on the intensity of horizontal, neutrino induced muons with energy above 1 TeV at the Soudan 2 detector. We set a limit of 1.8 x 10{sup {minus}13} (cm{sup 2} sr s){sup {minus}} for detecting 5 TeV {nu}-induced muons from AGN.

Date: June 22, 1999

Creator: DeMuth, D. M. & Collaboration, The Soudan 2

Item Type: Article

Partner: UNT Libraries Government Documents Department

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A drift chamber telescope for high-Z particles

Drift chambers are one of the position sensing technologies used in cosmic ray balloon and satellite experiments with potential application to the next generation of detectors for space flight. A low mass TPC type drift chamber, employing 8 distinct drift regions within a single gas volume has been built, tested and used at the LBL Bevalac. From the drift time X-coordinate, spatial resolutions below 100 {mu}m are obtained for a variety of heavy ions with selected trigger modes. The Y-coordinate… more

Date: February 1, 1990

Creator: Isbert, J.; Crawford, H.J.; Mathis, K.D.; Guzik, T.G.; Mitchell, J.W.; Wefel, J.P. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Experimental results obtained with the positron-annihilation- radiation telescope of the Toulouse-Argonne collaboration

We present laboratory measurements obtained with a ground-based prototype of a focusing positron-annihilation-radiation telescope developed by the Toulouse-Argonne collaboration. This balloon-borne telescope has been designed to collect 511-keV photons with an extremely low instrumental background. The telescope features a Laue diffraction lens and a detector module containing a small array of germanium detectors. It will provide a combination of high spatial and energy resolution (15 arc sec a… more

Date: October 1, 1995

Creator: Naya, J.E.; von Ballmoos, P.; Albernhe, F.; Vedrenne, G.; Smither, R.K.; Faiz, M. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

A space bourne crystal diffraction telescope for the energy range of nuclear transitions

Recent experimental work of the Toulouse-Argonne collaboration has opened for perspective of a focusing gamma-ray telescope operating in the energy range of nuclear transitions, featuring unprecedented sensitivity, angular and energy resolution. The instrument consists of a tunable crystal diffraction lens situated on a stabilized spacecraft, focusing gamma-rays onto a small array of Germanium detectors perched on an extendible boom. While the weight of such an instrument is less than 500 kg, i… more

Date: October 1, 1995

Creator: von Ballmoos, P.; Naya, J.E.; Albernhe, F.; Vedrenne, G.; Smither, R.K.; Faiz, M. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

The Pierre Auger project

The Pierre Auger project is a broadly based international effort to make a detailed study of cosmic rays at the highest energies. Two air shower detectors are proposed, one to be placed in the Northern Hemisphere and one in the Southern Hemisphere. Each installation will consist of an array of 1600 particle detectors spread over 3000 km{sup 2} with a solid angle acceptance of 2 sr for cosmic ray air showers. Eah installation will also have an atmospheric fluorescence detector viewing the volume… more

Date: January 1, 1996

Creator: Mantsch, P.M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Time profiles and pulse structure of bright, long gamma-ray bursts using BATSE TTS data

The time profiles of many gamma-ray bursts observed by BATSE consist of distinct pulses, which offer the possibility of characterizing the temporal structure of these bursts using a relatively small set of pulse-shape parameters. This pulse analysis has previously been performed on some bright, long bursts using binned data, and on some short bursts using BATSE Time-Tagged Event (TTE) data. The BATSE Time- to-Spill (TTS) burst data records the times required to accumulate a fixed number of phot… more

Date: April 1, 1996

Creator: Lee, A.; Bloom, E. & Scargle, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Review of crystal diffraction and its application to focusing energetic gamma rays

The basic features of crystal diffraction and their application to the construction of a crystal diffraction lens for focusing energetic gamma rays are described using examples from the work preformed at the Argonne National Laboratory. Both on-axis and off-axis performance are discussed. The review includes of normal crystals, bent crystals, and crystals with variable crystal-plane spacings to develop both condenser-type lenses and point-to-point imaging lenses.

Date: October 1, 1995

Creator: Smither, R.K.; Fernandez, P.B.; Graber, T.; von Ballmoos, P.; Naya, J.; Albernhe, F. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

The expected rates of X-ray flashes from GRBs in ROSAT and preliminary search results

The recent long (up to days) and relatively bright soft X-ray afterglows from GRBs detected by BeppoSAX raise the possibility of detecting similar events in the ROSAT database. The authors perform detailed calculations on the expected number of ROSAT events based on the extended halo scenario. They use the realistic ROSAT capabilities and the actual exposure time on bright nearby galaxies. They find that the expected number of x-ray events is quite low, {approximately} 1, and depends on the pea… more

Date: December 1, 1998

Creator: Li, H.; Sun, X. & Fenimore, E.E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

X-ray flashes in ROSAT PSPC data

The authors find 24 short (200--2,500s) X-ray flashes from all the ROSAT Position Sensitive Proportional Counter (PSPC) observations above galactic latitude 30 degrees ({approximately} 9.6 Msec) and some observations toward low latitudes ({approximately} 2.4 Msec). The brightest flash is quite extraordinary. Its flux rises from nondetection by a factor of > 200 in less than 100 sec. Its spectrum can be fitted either by a thermal plasma model with kT {ge} 2.4 keV, or by a single power-law with t… more

Date: December 1, 1998

Creator: Sun, X.; Li, H.; Fenimore, E.E. & Wang, Q.D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Dark matter axions `96

This report discusses why axions have been postulated to exist, what cosmology implies about their presence as cold dark matter in the galactic halo, how axions might be detected in cavities wherein strong magnetic fields stimulate their conversion into photons, and relations between axions` energy spectra and galactic halos` properties.

Date: December 31, 1996

Creator: Sikivie, P.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Response of the D0 calorimeter to cosmic ray muons

The D0 Detector at the Fermi National Accelerator Laboratory is a large multi-purpose detector facility designed for the study of proton-antiproton collision products at the center-of-mass energy of 2 TeV. It consists of an inner tracking volume, hermetic uranium/liquid argon sampling calorimetry, and an outer 4{pi} muon detector. In preparation for our first collider run, the collaboration organized a Cosmic Ray Commissioning Run, which took place from February - May of 1991. This thesis is a … more

Date: October 1, 1992

Creator: Kotcher, J.

Item Type: Thesis or Dissertation

Partner: UNT Libraries Government Documents Department

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Detection of cosmic ray tracks using scintillating fibers and position sensitive multi-anode photomultipliers

This experiment demonstrates detection of cosmic ray tracks by using Scintillating fiber planes and multi-anode photomultipliers (MA-PMTs). In a laboratory like this, cosmic rays provide a natural source of high-energy charged particles which can be detected with high efficiency and with nanosecond time resolution.

Date: February 1, 1998

Creator: Atac, M.; Streets, J. & Wilcer, N.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

A continuous watch of the northern sky above 40 TeV with the CYGNUS array

This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The aim of the project has been to continuously monitor the northern sky for transient high-energy gamma-ray emission from astrophysical sources. Potential objects of such emission include gamma-ray bursts and flares from active galaxies. At the start of this project, the CYGNUS extensive air shower array was used for the monitoring; CYGNUS has an e… more

Date: November 1, 1998

Creator: Haines, T.J.; Miller, R. & Sinnis, C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Results from the CACTI experiment: Air-Cerenkov and particle measurements of PeV air showers at Los Alamos

An array of six wide angle Cerenkov detectors was constructed amongst the scintillator and muon detectors of the CYGNUS II array at Los Alamos National Laboratory to investigate cosmic ray composition in the PeV region through measurements of the shape of Cerenkov lateral distributions. Data were collected during clear, moonless nights over three observing periods in 1995. Estimates of depths of shower maxima determined from the recorded Cerenkov lateral distributions align well with existing r… more

Date: July 1, 1997

Creator: Paling, S.; Hillas, A.M. & Berley, D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Overview of the GEM muon system cosmic ray test program at the SSCL

Muon track resolution exceeding 75-{mu}m per plane is one of the main strengths of the GEM detector design, and will be crucial in searches for Higgs Bosons, heavy Z-Bosons, technicolor, and supersymmetry. Achieving this resolution coal requires improved precision in muon chambers and their alignment. A cosmic ray test stand known as the Texas Test Rio, (TTR) has been created at the SSCL for studying candidate GEM muon chamber technologies. Test results led to selecting Cathode Strip Chambers (… more

Date: April 1, 1993

Creator: Milner, E.C.

Item Type: Article

Partner: UNT Libraries Government Documents Department