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arXiv · hep-ph/0505167

511 keV Gamma Ray from Moduli Decay in the Galactic Bulge

M. Kawasaki·T. Yanagida
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Abstract

We show that the $e^++e^-$ decay of a light scalar boson of mass 1-10 MeV may account for the fluxes of 511 keV gamma ray observed by SPI/INTEGRAL. We argue that candidates of such a light scalar boson is one of the string moduli or a scalar partner of the axion in a supersymmetric theory.

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M. Kawasaki, T. Yanagida. 2005-06-30. 511 keV Gamma Ray from Moduli Decay in the Galactic Bulge. https://doi.org/10.1016/j.physletb.2005.07.063

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