Context :

Aims : The interacting dark matter ( IDM ) scenario allows for the acceleration of the Universe without Dark Energy .

Methods : We constrain the IDM model by using the newly revised observational data including H ( z ) data and Union2 SNe Ia via the Markov chain Monte Carlo method .

Results : When mimicking the \Lambda CDM model , we obtain a more stringent upper limit to the effective annihilation term at \kappa C _ { 1 } \approx 10 ^ { -3.4 } Gyr ^ { -1 } , and a tighter lower limit to the relevant mass of Dark Matter particles at M _ { x } \approx 10 ^ { -8.6 } Gev .
When mimicking the w CDM model , we find that the effective equation of state of IDM is consistent with the concordance \Lambda CDM model and appears to be most consistent with the effective phantom model with a constant EoS for which w < -1 .

Conclusions :