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 ” for the detection of a significant fraction of generic spinning binaries in the comparable-mass regime ( m _ { 2 } / m _ { 1 } \lesssim 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 } \simeq 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 moderate spins ( \hat { \mathbf { L } } _ { N } \cdot \mathbf { S } / m ^ { 2 } \simeq 0.015 - 0.1 ) will cause considerable mismatches ( \sim 3 % – 25 % ) with non-spinning templates .
This is contrary to the expectation that neutron-star spins may not be relevant for GW detection .