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Signals from cosmic ray sources, some statistical issues (open access)

Signals from cosmic ray sources, some statistical issues

The possible existence of discrete sources of cosmic rays is presently one of the main topics of study in non-accelerator particle physics. The search is being conducted in a wide variety of experiments using UHE-{gamma} rays, VHE-{gamma} rays, EeV particles, underground {mu}'s and {nu}'s. The current experimental situation, however, can be described as chaotic. The number of claimed observations of sources by different groups using a variety of experimental techniques is quite large, but a consistent interpretation of the various results has failed to emerge. Most of the observations rely on either on dc excess'' from the direction of the source, a periodicity of the events from that direction, or some combination of these two effects. In the first section of this paper, we discuss some of the techniques that may be used in searching for a dc excess. We review two common bin free tests of the light curves. We discuss a particular problem involving phase coherence when doing a period search. This paper discusses some of the issues and meanings involved in combining probabilities from more than one test. Prescribing the right'' way to do analysis is certainly beyond this paper's scope. However some of the issues and …
Date: October 27, 1990
Creator: Goodman, M.
System: The UNT Digital Library
Application of Soil Venting at a Large Scale: A Data and Modeling Analysis (open access)

Application of Soil Venting at a Large Scale: A Data and Modeling Analysis

Soil venting will be applied at a demonstration scale to a site at the Idaho National Engineering Laboratory which is contaminated with carbon tetrachloride and other organic vapors. The application of soil venting at the site is unique in several aspects including scale, geology, and data collection. The containmented portion of the site has a surface area of over 47,000 square meters (12 acres) and the depth to the water table is approximately 180 meters. Migration of contaminants through the entire depth of the vadose zone is evidenced by measured levels of chlorinated solvents in the underlying aquifer. The geology of the site consists of a series of layered basalt flows interspersed with sedimentary interbeds. The depth of the vadose zone, the nature of fractured basalt flows, and the degree of contamination all tend to make drilling difficult and expensive. Because of the scale of the site, extent of contamination, and expense of drilling, a computer model has been developed to simulate the migration of the chlorinated solvents during plume growth and cleanup. The demonstration soil venting operation has been designed to collect pressure drop and plume migration data to assist with calibration of the transport model. The model will …
Date: February 27, 1990
Creator: Walton, J. C.; Baca, R. G.; Sisson, J. B. & Wood, T. R.
System: The UNT Digital Library
J/. psi. suppression: Catching up with the comovers (open access)

J/. psi. suppression: Catching up with the comovers

The combined role of inelastic scattering with nucleons and comoving secondary particles in J/{psi} suppression is explored. An analysis of the latest FNAL and CERN data suggests that the high-density comover contribution emerges with increasing incident energy and A.
Date: August 27, 1990
Creator: Vogt, R. (Lawrence Livermore National Lab., CA (USA) Lawrence Berkeley Lab., CA (USA)) & Gavin, S. (Helsinki Univ. (Finland). Research Inst. for Theoretical Physics)
System: The UNT Digital Library
Uses of Fabry-Perot Velocimeters in Studies of High Explosives Detonation (open access)

Uses of Fabry-Perot Velocimeters in Studies of High Explosives Detonation

The Fabry Perot has become an important and valuable tool by which explosive performance information can be obtained relatively easily and inexpensively. Principle uses of the Fabry Perot have been free surface, and particle velocity measurements in one dimensional studies of explosive performance. In the cylinder test, it has been very useful to resolve early wall motions. We have refined methods of characterizing new explosives i.e. equation of state, C-J pressure, via the cylinder shot, flat plate, and particle velocity techniques. All of these use Fabry Perot as one of the principle diagnostics. Each of these experimental techniques are discussed briefly and some of the results obtained. Modeling developed to fit Fabry-Perot results are described along with future testing.
Date: August 27, 1990
Creator: Breithaupt, R. D. & Tarver, C. M.
System: The UNT Digital Library
810 Future plans (open access)

810 Future plans

It is believed that a good bet for finding the Quark-Gluon Plasma at AGS energies is with the heaviest projectiles on the heaviest target, i.e. Au on Au. One of the likely signatures of the plasma is strangeness enhancement. Al Saulys has shown what it's like to find {Delta} and K{degree} with Si projectiles. Our Monte Carlo simulations show track densities 4 times higher for Au projectiles. In addition, the Au beam itself produces 30 times more ionization. Thus the present TPC's will be limited to only a few hundred ions per sec. This paper discusses plans for these experiments and modification to TPC. 9 figs.
Date: March 27, 1990
Creator: Etkin, A.; Foley, K. J.; Hackenburg, R. W.; Longacre, R. S.; Love, W. A.; Morris, T. W. et al.
System: The UNT Digital Library