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Title: Use of the Egret instrument in studies of the origin of the cosmic radiation

Abstract

This is a continuation of previous studies aimed at predicting spectral signatures of discrete cosmic-ray sources. In this paper, a formalism is developed for calculating gamma-ray spectra observed at Earth from the decay of neutral pions formed in collisions of cosmic-ray protons and ions with galactic gas and dust. The cosmic rays are assumed to be emitted by discrete sources, and their intensities and spectra are described by solutions to a diffusion equation. Calculations of spectral signatures expected from these hypothetical point sources of cosmic rays are presented. In particular, a steady source of cosmic rays could show a harder gamma-ray spectrum than the spectrum of the diffuse galactic background, whereas an impulsive source of cosmic rays could show a much softer spectrum. Observations of the angular variations of gamma-ray intensities and spectra near point sources will provide information on cosmic-ray propagation in other parts of our galaxy, as well as on the nature of the discrete sources themselves. Capabilities of the Egret telescope in mapping spectra from cosmic-ray point sources are briefly discussed. 14 refs., 2 figs.

Authors:
Publication Date:
Research Org.:
Lawrence Livermore National Lab., CA (USA)
Sponsoring Org.:
DOE/DP
OSTI Identifier:
5356237
Report Number(s):
UCRL-102243; CONF-900129-4
ON: DE90003595; TRN: 90-000470
DOE Contract Number:  
W-7405-ENG-48
Resource Type:
Conference
Resource Relation:
Conference: 21. international cosmic ray conference, Adelaide (Australia), 6-19 Jan 1990
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; GAMMA SPECTRA; CALCULATION METHODS; COSMIC GAMMA SOURCES; MEASURING INSTRUMENTS; TELESCOPES; COSMIC RAY SOURCES; SPECTRA; 640101* - Astrophysics & Cosmology- Cosmic Radiation

Citation Formats

Dermer, C.D. Use of the Egret instrument in studies of the origin of the cosmic radiation. United States: N. p., 1989. Web.
Dermer, C.D. Use of the Egret instrument in studies of the origin of the cosmic radiation. United States.
Dermer, C.D. Fri . "Use of the Egret instrument in studies of the origin of the cosmic radiation". United States. https://www.osti.gov/servlets/purl/5356237.
@article{osti_5356237,
title = {Use of the Egret instrument in studies of the origin of the cosmic radiation},
author = {Dermer, C.D.},
abstractNote = {This is a continuation of previous studies aimed at predicting spectral signatures of discrete cosmic-ray sources. In this paper, a formalism is developed for calculating gamma-ray spectra observed at Earth from the decay of neutral pions formed in collisions of cosmic-ray protons and ions with galactic gas and dust. The cosmic rays are assumed to be emitted by discrete sources, and their intensities and spectra are described by solutions to a diffusion equation. Calculations of spectral signatures expected from these hypothetical point sources of cosmic rays are presented. In particular, a steady source of cosmic rays could show a harder gamma-ray spectrum than the spectrum of the diffuse galactic background, whereas an impulsive source of cosmic rays could show a much softer spectrum. Observations of the angular variations of gamma-ray intensities and spectra near point sources will provide information on cosmic-ray propagation in other parts of our galaxy, as well as on the nature of the discrete sources themselves. Capabilities of the Egret telescope in mapping spectra from cosmic-ray point sources are briefly discussed. 14 refs., 2 figs.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1989},
month = {10}
}

Conference:
Other availability
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