Sensitivity of indirect detection of Neutralino dark matter by Sommerfeld enhancement mechanism

We have investigated neutralino dark matter in the framework of minimal supersymmetric Standard Model focusing on the coannihilatioin region. In this region, where the particle whose mass is tightly degenerated with the neutralino dark matter exists, we can solve the Lithium problem in the case of lepton flavor being violated. It turns out that Sommerfeld enhancement is important in the coannihilation region so that the dark matter signal becomes large enough to be observed by the current sensitivity of indirect experiments.