A hypercritical accretion scenario in Central Compact Objects accompanied with an expected neutrino burst

TL;DR

This paper proposes a hypercritical accretion model for Central Compact Objects (CCOs), suggesting their magnetic fields are buried during early neutron star formation, with neutrino bursts serving as potential observational evidence.

Contribution

It introduces a new scenario based on magnetohydrodynamic simulations that explains the low magnetic fields of CCOs through early magnetic burial during hypercritical accretion.

Findings

Neutrino bursts are predicted during the hypercritical phase.

Neutrino flavor ratios could be detected on Earth.

The model explains the low magnetic fields observed in CCOs.

Abstract

The measurement of the period and period derivative, and the canonical model of dipole radiation have provided a method to estimate the low superficial magnetic fields in the so-called Central Compact Objects (CCOs). In the present work, a scenario is introduced in order to explain the magnetic behavior of such CCOs. Based on magnetohydrodynamic simulations of the post core-collapse supernova phase during the hypercritical accretion episode, we argue that the magnetic field of a newborn neutron star could have been early buried. During this phase, thermal neutrinos are created mainly by the pair annihilation, plasmon decay, photo-neutrino emission and other processes. We study the dynamics of these neutrinos in this environment and also estimate the number expected of the neutrino events with their flavor ratios on Earth. The neutrino burst is the only viable observable that could provide compelling evidence of the hypercritical phase and therefore, the hidden magnetic field mechanism as the most favorable scenario to explain the anomalous low magnetic fields estimated for CCOs.