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A<sc>bstract</sc> In studying secondary gamma-ray emissions from Primordial Black Holes (PBHs), the production of scalar particles like pions and axion-like particles (ALPs) via Hawking radiation is crucial. While previous analyses assumed relativistic production, asteroid-mass PBHs, relevant to upcoming experiments like AMEGO-X, likely produce pions and ALPs non-relativistically when their masses exceed 10 MeV. To account for mass dependence in Hawking radiation, we revisit the greybody factors for massive scalars from Schwarzschild black holes, revealing significant mass corrections to particle production rates compared to the projected AMEGO-X sensitivity. We highlight the importance of considering non-relativisticπ0production in interpreting PBH gamma-ray signals, essential for determining PBH properties. Additionally, we comment on the potential suppression of pion production due to form factor effects when producing extended objects via Hawking radiation. We also provide an example code for calculating the Hawking radiation spectrum of massive scalar particles Image missing<#comment/>.
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This content will become publicly available on March 4, 2026
Looking for traces of Hawking radiation in correlation functions of BEC acoustic black holes
Renaud Parentani was one of the leading figures in Quantum Field Theory in curved spacetime, in particular concerning its applications to Hawking-like radiation in analogue models. In this paper dedicated to him, we discuss the characteristic features appearing in the correlation functions in an acoustic black hole formed by a Bose–Einstein condensate, considered as signature of the presence of Hawking radiation in this system.
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- Award ID(s):
- 2309186
- PAR ID:
- 10586110
- Publisher / Repository:
- Academia des Sciences, Institut de France
- Date Published:
- Journal Name:
- Comptes Rendus. Physique
- Volume:
- 25
- Issue:
- S2
- ISSN:
- 1878-1535
- Page Range / eLocation ID:
- 1 to 15
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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