Cosmological Constraint on the Minimal Universal Extra Dimension Model

We investigate the relic abundance of dark matter in the minimal universal extra dimension model including resonance processes by second Kaluza-Klein (KK) particles in all coannihilation processes. After including second KK resonance processes, the relic abundance of dark matter is reduced by about 30%. Thus, the cosmologically allowed compactification scale 1/R is 600 GeV < 1/R < 1400 GeV.