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Résumé |
In SUGRA, gravitino is predicted as a super partner of graviton. For
weak scale mass of gravitino due to the SUSY breaking which at least
gravitino is supposed to obtain, it is known that gravitino has a long
lifetime due to the gravitational interaction and inevitably decays
during/after the epoch of big-bang nucleosynthesis. Due to the decay
of gravitino, high energy particles are emitted, which modifies light
element abundances and may disagree with observations. This is called
the gravitino problem. If gravitino is the lightest SUSY Particle
(LSP), the next LSP decays into gravitino, which induces the similar
problem. I introduce recent progresses on those topics by reviewing a
serris of our works on cosmological constraints on gravitino
including our recent paper (arXiv:1709.01211 [hep-ph]) in which we updated our own bounds
in astro-ph/0408426.
In addition, I also mention our updated constrains on annihilating cold dark matter (like WIMP)
given in arXiv:1509.03665, which have less astrophysical ambiguities. |
