Open AccessGravitational‐wave background of neutron star–white dwarf binaries
Author(s) -
Cooray Asantha
Publication year - 2004
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1111/j.1365-2966.2004.08152.x
Subject(s) - physics , white dwarf , neutron star , astrophysics , gravitational wave , astronomy , luminosity function , luminosity , stars , galaxy
We discuss the stochastic background of gravitational waves from ultra‐compact neutron star–white dwarf (NS–WD) binaries at cosmological distances. Under the assumption that accreting neutron stars and donor white dwarf stars form most of the low‐mass X‐ray binaries (LMXBs), our calculation makes use of recent results related to the luminosity function determined from X‐ray observations. Even after accounting for detached NS–WD binaries not captured in X‐ray data, the NS–WD background is at least an order of magnitude below that due to extragalactic white dwarf–white dwarf binaries and below the detectability level of the Laser Interferometer Space Antenna ( LISA ) at frequencies between 10 −5 and 10 −1 Hz. While the extragalactic background is unlikely to be detected, we suggest that around one to 10 galactic NS–WD binaries may be resolved with LISA such that their positions are determined to an accuracy of several degrees on the sky.