GRAVITATIONAL WAVE BACKGROUND from BINARY MERGERS and METALLICITY EVOLUTION of GALAXIES

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

The cosmological evolution of the binary black hole (BH) merger rate and the energy density of the gravitational wave (GW) background are investigated. To evaluate the redshift dependence of the BH formation rate, BHs are assumed to originate from low-metallicity stars, and the relations between the star formation rate, metallicity and stellar mass of galaxies are combined with the stellar mass function at each redshift. As a result, it is found that when the energy density of the GW background is scaled with the merger rate at the local universe, the scaling factor does not depend on the critical metallicity for the formation of BHs. Also taking into account the merger of binary neutron stars, a simple formula to express the energy spectrum of the GW background is constructed for the inspiral phase. The relation between the local merger rate and the energy density of the GW background will be examined by future GW observations.

Original languageEnglish
Article number146
JournalAstrophysical Journal
Volume832
Issue number2
DOIs
Publication statusPublished - Dec 1 2016

Fingerprint

gravitational waves
merger
metallicity
flux density
stellar mass
energy
binary stars
star formation rate
neutron stars
energy spectra
universe
rate
galaxies
scaling
stars

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

GRAVITATIONAL WAVE BACKGROUND from BINARY MERGERS and METALLICITY EVOLUTION of GALAXIES. / Nakazato, Ken'ichiro; Niino, Yuu; Sago, Norichika.

In: Astrophysical Journal, Vol. 832, No. 2, 146, 01.12.2016.

Research output: Contribution to journalArticle

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