Upper limit to the diffuse cosmic ultrahigh-energy. gamma. spectrum

Journal Article · Fri Nov 01 04:00:00 EST 1991 · Physical Review, D (Particles Fields); (United States)

DOI:https://doi.org/10.1103/PhysRevD.44.R2635· OSTI ID:6135959

He, Y D ^[1]; Zhu, Q Q ^[2]

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1. Department of Physics and Space Sciences Laboratory, University of California, Berkeley, California (USA) Nuclear Science Division, Lawrence Berkely Laboratory, Berkeley, California (USA)
2. Institute of High Energy Physics, Academia Sinica, Beijing 100039 (China) Istituto Nazionale di Fisica Nucleare, 67010, Assergi (AQ) (Italy)

An upper limit to the difuse cosmic ultrahigh-energy (UHE) {gamma} spectrum from {similar to}5 TeV up to {similar to}1 PeV is inferred from data on the spectrum of the electromagnetic component of secondary cosmic rays recorded by emulsion-chamber experiments at various atmospheric depths. Our Monte Carlo simulation of the atmospheric propagation and interaction of the photons and protons with primary energies of (5{times}10{sup 12})--10{sup 15} eV shows that the intensity of uncorrelated {gamma} events with visible energies {ital E}{sub {gamma}}=5--100 TeV observed in emulsion-chamber experiments is sensitive to the diffuse cosmic UHE {gamma} rays at the level of {similar to}10{sup {minus}3} compared to primary cosmic rays in the same energy region, depending on the atmospheric depth of the observation level. We also discuss the relevance of the UHE {gamma} spectrum to topics such as diffuse photons as by-products of the energy loss of extragalactic cosmic rays interacting with the cosmic 2.7 K background radiation, direct photons as a result of possible new production mechanisms, and photons as products of radiative decay of unstable cosmological relic neutrinos of mass {similar to}5 TeV--1 PeV.

• DOE Contract Number: AC03-76SF00098
• OSTI ID: 6135959
• Journal Information: Physical Review, D (Particles Fields); (United States), Journal Name: Physical Review, D (Particles Fields); (United States) Vol. 44:9; ISSN PRVDA; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

662340 -- Hadron Interactions-- (1992-)
662390* -- Electromagnetic Processes & Properties-- (1992-)
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BASIC INTERACTIONS
BOSONS
CASCADE SHOWERS
COSMIC PHOTONS
COSMIC RADIATION
ELECTROMAGNETIC INTERACTIONS
ELECTROMAGNETIC RADIATION
ELEMENTARY PARTICLES
ENERGY RANGE
ENERGY SPECTRA
GAMMA SPECTRA
HADRON-HADRON INTERACTIONS
INTERACTIONS
IONIZING RADIATIONS
MASSLESS PARTICLES
MICROWAVE RADIATION
MONTE CARLO METHOD
MULTIPLE PRODUCTION
NUCLEAR EMULSIONS
PARTICLE INTERACTIONS
PARTICLE PRODUCTION
PEV RANGE
PHOTONS
PHOTOPRODUCTION
RADIATIONS
RELICT RADIATION
SECONDARY COSMIC RADIATION
SHOWERS
SPECTRA
TEV RANGE