English

Retrieving the True Masses of Gravitational-wave Sources

High Energy Astrophysical Phenomena 2019-07-18 v1 General Relativity and Quantum Cosmology

Abstract

Gravitational waves (GWs) encode important information about the mass of the source. For binary black holes (BBHs), the templates that are used to retrieve the masses normally are developed under the assumption of a vacuum environment. However, theories suggest that some BBHs form in gas-rich environments. Here we study the effect of hydrodynamic drag on the chirp signal of a stellar-mass BBH and the impact on the measurement of the mass. Based on theoretical arguments, we show that the waveform of a BBH in gas resembles that of a more massive BBH residing in a vacuum. The effect is important for LISA sources but negligible for LIGO/Virgo binaries. Furthermore, we carry out a matched-filtering search of the best fitting parameters. We find that the best-fit chirp mass could be significantly greater than the real mass if the gas effect is not appropriately accounted for. Our results have important implications for the future joint observation of BBHs using both ground- and space-based detectors.

Keywords

Cite

@article{arxiv.1906.11055,
  title  = {Retrieving the True Masses of Gravitational-wave Sources},
  author = {Xian Chen and Zhe-Feng Shen},
  journal= {arXiv preprint arXiv:1906.11055},
  year   = {2019}
}

Comments

5 pages, 1 figure. This is a contribution to the conference proceedings: Recent Progress in Relativistic Astrophysics, Fudan University, China