Authors: P. Ajith
Date: 6 Jul 2011
Abstract: This paper presents a post-Newtonian (PN) template family of gravitational waveforms from inspiralling compact binaries with non-precessing spins, where the spin effects are described by a single "reduced-spin" parameter. This template family, which reparametrizes all the spin-dependent PN terms in terms of the leading-order (1.5PN) spin-orbit coupling term in an approximate way, has very high overlaps (fitting factor > 0.99) with non-precessing binaries with arbitrary mass ratios and spins. We also show that this template family is "effectual" towards a significant fraction of generic spinning binaries in the comparable-mass regime (m_2/m_1 < 10), providing an attractive and feasible way of searching for gravitational waves (GWs) from spinning low-mass binaries. We also show that the secular (non-oscillatory) spin-dependent effects in the phase evolution (which are taken into account by the non-precessing templates) are more important than the oscillatory effects of precession in the comparable-mass (m_1 ~= m_2) regime. Hence the effectualness of non-spinning templates is particularly poor in this case, as compared to non-precessing-spin templates. For the case of binary neutron stars observable by Advanced LIGO, even small spins (L_N . S/mˆ2 ~= 0.1) will cause significant de-phasing with non-spinning templates. This is contrary to the expectation that neutron-star spins may not be relevant for GW detection.
© M. Vallisneri 2012 — last modified on 2010/01/29
Tantum in modicis, quantum in maximis