Probing the low-energy spectrum of non-thermal electrons in galaxy clusters with soft gamma ray observations

  • P. MarchegianiEmail author
Original Article


In this paper we study the possibility of probing the low-energy part of the spectrum of non-thermal electrons in galaxy clusters by detecting their non-thermal bremsstrahlung (NTB) emission in the soft gamma ray band, using instruments like e-ASTROGAM. Using the Coma cluster as a reference case, we find that, for very low values of the minimum energy of the electrons, in principle the NTB is detectable, but this situation is possible only for conditions that can be maintained only for a short time compared to the cluster lifetime. The possibility of constraining the low energy spectrum of non-thermal electrons through NTB is therefore hard to achieve in next years.


Gamma rays: galaxies: clusters Galaxies: clusters: general 



This work is based on the research supported by the South African Research Chairs Initiative of the Department of Science and Technology and National Research Foundation of South Africa (Grant No. 77948). PM acknowledges support from the Department of Science and Technology/National Research Foundation (DST/NRF) Square Kilometre Array (SKA) post-graduate bursary initiative under the same Grant. I thank the Referee for useful comments and suggestions.


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© Springer Nature B.V. 2019

Authors and Affiliations

  1. 1.School of PhysicsUniversity of the WitwatersrandJohannesburgSouth Africa

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