Late decaying axino as CDM and its lifetime bound
نویسندگان
چکیده
The axino with mass in the GeV region can be cold dark matter(CDM) in the galactic halo. However, if R-parity is broken, for example by the bilinear terms, then axino(ã) can decay to ν + γ. In this case, the most stringent bound on the axino lifetime comes from the diffuse photon background and we obtain that the axino lifetime should be greater than 3.9 × 10Ωãh s which amounts to a very small bilinear R-parity violation, i.e. μα < 1 keV. This invalidates the atmospheric neutrino mass generation through bilinear R-violating terms in SUSY. [
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تاریخ انتشار 2001