2006/02/28 by Shinta Kasuya, Masahiro Kawasaki · 1 citation
Physics and Astronomy · #Astrophysical Phenomena and Observations #Astrophysics and Cosmic Phenomena #Galaxies: Formation, Evolution, Phenomena #astro-ph #hep-ph
paper · pdf · doi:10.1103/physrevd.73.063007
published as Phys.Rev. D73 (2006) 063007 · 6 pages, 5 figures, published version
openalex publication_date 2006/03/16 · arxiv created 2006/03/23 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We obtain the spectrum of gamma-ray emissions from the moduli whose decay into e+e^\ensuremath- accounts for the 511 keV line observed by SPI/INTERGRAL. The moduli emit gamma rays through internal bremsstrahlung, and also decay directly into two gammas via tree and/or one-loop diagrams. We show that the internal bremsstahlung constrains the mass of the moduli below \ensuremath∼40 MeV model-independently. On the other hand, the flux of two gammas directly decayed from the moduli through one-loop diagrams will exceed the observed galactic diffuse gamma-ray background if the moduli mass exceeds \ensuremath∼20 MeV in the typical situation. Moreover, forthcoming analysis of SPI data in the range of 1--8 MeV may detect the line emisson with the energy half the moduli mass in the near future, which confirms the decaying moduli scenario.