Impact of axions on the Cassiopea A neutron star cooling

Understand

The observed anomalous steady decrease in surface temperature of the supernova remnant Cassiopeia A (Cas A), which was reported about ten years ago, has generated much debate.

• Several exotic cooling scenarios have been proposed using non-standard assumptions about the physics and evolution of this neutron star (NS).
• At present, significant corrections have been made to the observational data, which make it possible to numerically simulate the Cas A NS cooling process in the framework of the scenario of minimal neutrino cooling.
• If there is an additional source of cooling, such as axion emission, the steepness of the Cas A NS surface temperature drop will increase with the growth of the axion-nucleon interaction strength.