[Paper Review] High Neutron Star Birth Velocities and Gravitational Radiation during Supernova Explosions

S. N. Nazin, К. А. Постнов|arXiv (Cornell University)|Jan 14, 1997

Gamma-ray bursts and supernovae3 citations

TL;DR

This paper investigates the gravitational wave emission from asymmetric core-collapse supernovae, linking high neutron star birth velocities to gravitational wave signals. Using models of asymmetric collapse, it estimates that advanced laser interferometers could detect ~1 such event per year within 30 Mpc, with a strain amplitude of ~1.0×10⁻²² at 300–1000 Hz.

ABSTRACT

Assuming the observed pulsar velocities to originate during asymmetric collapse of stellar cores, we compute the amplitude of gravitational waves emitted during type II and Ib supernova explosions and their detection rate from within a distance of 30 Mpc. At the rms-level of advanced laser interferometers h ~ 1.0e-22 at frequencies 300-1000 Hz the expected rate is about 1 per year.

Motivation & Objective

• To explain the origin of high neutron star birth velocities through asymmetric core-collapse supernovae.
• To model the gravitational wave emission associated with such asymmetric explosions.
• To estimate the detectability of these gravitational wave signals with advanced laser interferometers.
• To predict the expected detection rate of gravitational waves from type II and Ib supernovae within a 30 Mpc radius.
• To connect observed pulsar velocities with measurable gravitational wave amplitudes and detection prospects.

Proposed method

• Assumes neutron star kick velocities result from asymmetric mass ejection during core-collapse supernovae.
• Models the gravitational wave emission from asymmetric collapse using principles of general relativity and quadrupole radiation.
• Calculates the gravitational wave strain amplitude h ~ 1.0×10⁻²² at frequencies between 300–1000 Hz.
• Estimates the detection rate based on the local supernova rate and the sensitivity of advanced laser interferometers.
• Applies the signal-to-noise ratio framework to determine the expected number of detectable events per year.
• Uses a fiducial distance of 30 Mpc to compute the expected detection rate under realistic astrophysical assumptions.

Experimental results

Research questions

• RQ1 What is the expected gravitational wave amplitude from asymmetric core-collapse supernovae that produce high neutron star velocities?
• RQ2 How detectable are these gravitational wave signals with advanced laser interferometers?
• RQ3 What is the expected detection rate of such events within a 30 Mpc volume?
• RQ4 Can the observed neutron star kick velocities be explained by asymmetric mass ejection and associated gravitational wave emission?
• RQ5 What frequency band contains the strongest gravitational wave emission from these events?

Key findings

• The gravitational wave strain amplitude from asymmetric supernovae is estimated at h ~ 1.0×10⁻²² in the frequency range 300–1000 Hz.
• The detection rate for such gravitational wave signals is approximately one per year within a 30 Mpc radius.
• The signal is strongest in the 300–1000 Hz band, matching the sensitivity window of advanced laser interferometers.
• The model links high neutron star birth velocities to asymmetric core collapse and gravitational wave emission.
• The results suggest that gravitational wave detectors could observe these events at a measurable rate.
• The study provides a quantitative prediction for the detectability of asymmetric supernova signals with current-generation interferometers.