Tight Bound on the Neutron Star Radius with Quasiperiodic Oscillations in Short Gamma-Ray Bursts

Journal Article · 09 April 2025 · The Astrophysical Journal

DOI: https://doi.org/10.3847/1538-4357/adc101 · OSTI ID:2554104

Guedes, Victor; Radice, David ; Chirenti, Cecilia ; Yagi, Kent

Abstract Quasiperiodic oscillations (QPOs) have been recently discovered in the short gamma-ray bursts (GRBs) 910711 and 931101B. Their frequencies are consistent with those of the quasiradial and quadrupolar oscillations of binary neutron star (BNS) merger remnants, as obtained in numerical relativity simulations. These simulations reveal quasi-universal relations between the remnant oscillation frequencies and the tidal coupling constant of the binaries. Under the assumption that the observed QPOs are due to these postmerger oscillations, we use the frequency–tide relations in a Bayesian framework to infer the source redshift, as well as the chirp mass and the binary tidal deformability of the BNS progenitors for GRBs 910711 and 931101B. We further use this inference to estimate bounds on the mass–radius relation for neutron stars. By combining the estimates from the two GRBs, we find a 68% credible range $R_{1.4}=12.48_{-0.40}^{+0.41}$ km for the radius of a neutron star with mass M = 1.4 M _⊙ , which is one of the tightest bounds to date.

• Sponsoring Organization: USDOE
• Grant/Contract Number: SC0021177; SC0024388
• OSTI ID: 2554104
• Journal Information: The Astrophysical Journal, Journal Name: The Astrophysical Journal Journal Issue: 2 Vol. 983; ISSN 0004-637X
• Publisher: American Astronomical SocietyCopyright Statement
• Country of Publication: United States
• Language: English