Cooling of young neutron stars in GRB associated to supernovae

Context. The traditional study of neutron star cooling has been generally applied to quite old objects such as the Crab Pulsar (957 years) or the central compact object in Cassiopeia A (330 years) with an observed surface temperature ~106 K. However, recent observations of the late (t = 108–109 s) emission of the supernovae (SNe) associated to GRBs (GRB-SN) show a distinctive emission in the X-ray regime consistent with temperatures ~107–108 K. Similar features have been also observed in two Type Ic SNe SN 2002ap and SN 1994I that are not associated to GRBs.