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arXiv · 1311.4820

An upper limit on the cosmic-ray luminosity of individual sources from gamma-ray observations

A. D. Supanitsky·V. de Souza
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Abstract

Different types of extragalactic objects are known to produce TeV gamma-rays. Some of these objects are the most probable candidates to accelerate cosmic rays up to 10^20 eV. It is very well known that gamma-rays can be produced as a result of the cosmic ray propagation through the intergalactic medium. These gamma-rays contribute to the total flux observed in the direction of the source. In this paper we propose a new method to derive an upper limit on the cosmic-ray luminosity of an individual source based on the measured upper limit on the integral flux of GeV-TeV gamma-rays. We show how it is possible to calculate an upper limit on the cosmic-ray luminosity of a particular source and we explore the parameter space in which the current GeV-TeV gamma-ray measurements can offer a useful determination. We study in detail two particular sources, Pictor A and NGC 7469, and we calculate the upper limit on the proton luminosity of each source based on the upper limit on the integral gamma-ray flux measured by the H.E.S.S. telescopes.

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A. D. Supanitsky, V. de Souza. 2013-11-19. An upper limit on the cosmic-ray luminosity of individual sources from gamma-ray observations. https://doi.org/10.1088/1475-7516%2F2013%2F12%2F023

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