511 keV line and diffuse gamma rays from moduli

  title={511 keV line and diffuse gamma rays from moduli},
  author={S. Kasuya and M. Kawasaki},
  journal={Physical Review D},
We obtain the spectrum of gamma-ray emissions from the moduli whose decay into e{sup +}e{sup -} 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 {approx}40 MeV model-independently. On the other hand, the flux of two gammas directly decayed from the moduli through one-loop… Expand

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