Cooling of a rotating strange star with a crust

As a strange star spins down, the nuclear matter in its crust contracts continuously into the quark core. The confined nuclear matter is dissolved into quark matter, liberating a lot of thermal energy. This process is called deconfinement heating. It is found that deconfinement heating dramatically changes the thermal evolution of a strange star. For a strange star with a strong surface magnetic field (∼ 1012 Gauss), the star heats instead of cooling during the first 10 years. Therefore, contrary to the previous studies, we conclude that there is evidence for strange quark matter, if a heating period is observed for a very young pulsar. For a strange star with a weaker magnetic field, the surface temperature is higher than that of a neutron star in the photon cooling era. This could also signal the existence of strange quark matter.