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Updated: Aug 24, 2026

Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Gamma rays from the Galactic bulge and large extra dimensions
Michel Cassé1, Jacques Paul, Gianfranco Bertone
1DAPNIA/Service d'Astrophysique, CEA-Saclay, 91191 Gif-sur-Yvette, France.
Abstract:
An intriguing feature of extra dimensions is the possible production of Kaluza-Klein gravitons by nucleon-nucleon bremsstrahlung, in the course of core collapse of massive stars, with gravitons then being trapped around the newly born neutron stars and decaying into two gamma rays, making neutron stars gamma-ray sources. We strengthen the limits on the radius of compactification of extra dimensions for a small number n of them, or alternatively the fundamental scale of quantum gravity, considering the gamma-ray emission of the whole population of neutron stars sitting in the Galactic bulge, instead of the closest member of this category. For n=1 the constraint on the compactification radius is R<400 microm.
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