Possible indirect confirmation of the existence of Pop III massive stars by gravitational wave
Abstract
We perform population synthesis simulations for Population III (Pop III) coalescing compact binary which merges within the age of the Universe. We found that the typical mass of Pop III binary black holes (BHBHs) is ∼30 M_{⊙} so that the inspiral chirp signal of gravitational waves can be detected up to z = 0.28 by KAGRA, Adv. LIGO, Adv. Virgo and GEO network. Our simulations suggest that the detection rate of the coalescing Pop III BHBHs is 140(68) events yr^{1 (SFR_p/(10^{2.5} M_{⊙} yr^{1} Mpc^{3}))\cdot Err_{sys}} for the flat (Salpeter) initial mass function, respectively, where SFR_{p} and Err_{sys} are the peak value of the Pop III star formation rate and the possible systematic errors due to the assumptions in Pop III population synthesis, respectively. Err_{sys} = 1 corresponds to conventional parameters for Pop I stars. From the observation of the chirp signal of the coalescing Pop III BHBHs, we can determine both the mass and the redshift of the binary for the cosmological parameters determined by the Planck satellite. Our simulations suggest that the cumulative redshift distribution of the coalescing Pop III BHBHs depends almost only on the cosmological parameters. We might be able to confirm the existence of Pop III massive stars of mass ∼30 M_{⊙} by the detections of gravitational waves if the merger rate of the Pop III massive BHBHs dominates that of Pop I BHBHs.
 Publication:

Monthly Notices of the Royal Astronomical Society
 Pub Date:
 August 2014
 DOI:
 10.1093/mnras/stu1022
 arXiv:
 arXiv:1402.6672
 Bibcode:
 2014MNRAS.442.2963K
 Keywords:

 gravitational waves;
 binaries: general;
 Astrophysics  High Energy Astrophysical Phenomena;
 Astrophysics  Solar and Stellar Astrophysics;
 General Relativity and Quantum Cosmology
 EPrint:
 Accepted for publication in MNRAS