Neutron Star Kicks and Supernova Asymmetry

TL;DR

This paper reviews the physical mechanisms behind neutron star kicks and supernova asymmetry, discussing hydrodynamic, neutrino-magnetic, and electromagnetic models, and analyzing recent observational constraints.

Contribution

It provides a comprehensive review of proposed kick mechanisms and evaluates their viability based on current observational data.

Findings

Hydrodynamic mechanisms can produce large neutron star kicks.

Neutrino-magnetic field interactions are plausible contributors.

Electromagnetic mechanisms depend on initial neutron star properties.

Abstract

Observations over the last decade have shown that neutron stars receive a large kick velocity (of order a hundred to a thousand km/s) at birth. The physical origin of the kicks and the related supernova asymmetry is one of the central unsolved mysteries of supernova research. We review the physics of different kick mechanisms, including hydrodynamically driven, neutrino -- magnetic field driven, and electromagnetically driven kicks. The viabilities of the different kick mechanisms are directly related to the other key parameters characterizing nascent neutron stars, such as the initial magnetic field and the initial spin. Recent observational constraints on kick mechanisms are also discussed.