Numerical analysis of quasiperiodic oscillations in the Hartle-Thorne spacetime

TL;DR

This paper numerically investigates quasiperiodic oscillations in neutron star systems using the Hartle-Thorne spacetime, estimating fundamental frequencies and comparing models to observational data.

Contribution

It introduces a detailed analysis of QPOs within the Hartle-Thorne metric and compares its predictions with other relativistic models using MCMC methods.

Findings

Three out of eight neutron star sources are well explained by the Hartle-Thorne model.

The study provides estimated error bars for QPO frequency measurements.

Comparison shows the Hartle-Thorne model can match observational data for certain sources.

Abstract

We numerically analyze quasiperiodic oscillations (QPOs) using a well-established spacetime model with neutron star sources. Within the framework of general relativity, we present expressions for the fundamental frequencies of test particles in the gravitational field of a slowly rotating and slightly deformed compact object defined by the Hartle-Thorne (HT) metric. Using the Relativistic Precession Model (RPM) formulated by Stella and Morinsk, we examine quasiperiodic oscillation data from eight neutron stars in low-mass X-ray binary systems. Employing Markov Chain Monte Carlo analyses with the Metropolis-Hastings algorithm, we estimate 1-$\sigma$ and 2-$\sigma$ error bars. Finally, we compare our results with predictions from the Schwarzschild, Lense-Thirring, and Kerr metrics, demonstrating that three of the eight sources can be well explained within the Hartle-Thorne model.