2048273
Chaotic behavior of particle production in branching processes.
The notion of chaotic behavior is examined for particle production in branching processes. Two types of branching are considered: non-Abelian gauge interaction and an Abelian cascade model. Properties of the production processes are investigated by Monte Carlo simulation. The {open_quote}{open_quote}temporal{close_quote}{close_quote} behavior is studied by following the fluctuations in the multiplicities of each generation as the branching evolves. The {open_quote}{open_quote}spatial{close_quote}{close_quote} behavior is described in terms of the fluctuations of the normalized factorial moments from event to event. The information dimension and a new entropy index are determined. When all the measures are taken together, they collectively give a strong suggestion that the QCD branching process is chaotic, while the Abelian cascade model is not. {copyright} {ital 1996 The American Physical Society.}
119433367
The Composition of Cosmic Rays at the Knee
The observation of a small change in spectral slope, or knee in the fluxes of cosmic rays near energies 10 15 eV has caused much speculation since its discovery over 40 years ago. The origin of this feature remains unknown. A small workshop to review some modern experimental measurements of this region was held at the Adler Planetarium in Chicago, USA in June 2000. This paper summarizes the results presented at this workshop and the discussion of their interpretation in the context of hadronic models of atmospheric air showers. 2002 Elsevier Science B.V. All rights reserved.
123445006
Status of LHAASO updates from ARGO-YBJ
Abstract The Large High Altitude Air Shower Observatory (LHAASO) is a multipurpose project with a complex detector array for high energy gamma ray and cosmic ray detection. The array of 1 km 2 is composed of five types of detectors to measure shower arrival direction, total number of secondary particles, muon content, Cherenkov image and high energy gamma rays near shower core, respectively. The main scientific goals are (1) searching for galactic cosmic ray origins by extensive spectroscopy investigations of gamma ray sources above 30 TeV; (2) all sky survey for gamma ray sources at energies higher than 300 GeV; (3) energy spectrum and composition measurements of cosmic rays over a wide range covering knees with fixed energy scale and known fluxes for all species at the low energy end. In this paper, the progress on relevant detector developments is reported, including constructions of prototype detectors at Tibet site and coincidence operation with the ARGO-YBJ resistive plat chamber full coverage array at 4300 m a.s.l. The energy spectrum of cosmic ray hydrogen and Helium nuclei up to 0.8 PeV is reported as the first piece of physics measurements by the LHAASO experiment.
123646598
Progress in Very High Energy Neutrino Astronomic Experiments
In this review, I will report progress in UHE neutrino search using existing experiments and status of constructing detectors. Physics relevant to UHE neutrinos are updated as well.
121925364
SEARCH FOR 10 TEV GAMMA-RAY EMISSION FROM ACTIVE GALACTIC NUCLEI WITH THE TIBET AIR SHOWER ARRAY
117043052
SEARCH FOR 10 TeV BURST-LIKE EVENTS COINCIDENT WITH THE BATSE BURSTS USING THE TIBET AIR SHOWER ARRAY
15989714
Deuteron electromagnetic form factors in the intermediate energy region.
Based on a perturbative QCD analysis of the deuteron form factor, a model for the reduced form factor is suggested. The numerical result is consistent with the data in the intermediate energy region. {copyright} {ital 1996 The American Physical Society.}