The new $(g-2)_\mu$ and Right-Handed Sneutrino Dark Matter.

In this paper we offer an explanation of the $(g-2)_\mu$ discrepancy in a R-parity conserving supersymmetric model with right-handed neutrinos in which the right-handed sneutrino is a viable dark matter candidate. We find that our scenario satisfies all up to date constraints including the latest results on $(g-2)_{\mu}$. Since right-handed sneutrinos are singlets, no new contributions for $\delta a_{\mu}$ with respect to the next to minimal supersymmetric Standard Model are present. However, the possibility to have the right-handed sneutrino as the lightest supersymmetric particle opens new ways to escape Large Hadron Collider and dark matter constraints. We find that dark matter masses within $10 \lesssim m_{\tilde{\nu}_{R}} \lesssim 600$ GeV are fully compatible with current experimental constraints. In addition, future dark matter direct detection experiments will be able to explore a sizable portion of the allowed parameter space with $m_{\tilde{\nu}_{R}} \lesssim 300$ GeV, while indirect detection experiments will be able to probe a much smaller fraction within $200 \lesssim m_{\tilde{\nu}_{R}} \lesssim 350$ GeV.