February 18, 1999 CfA Colloquium


Title: Gravitational Radiation from Accreting Neutron Stars: Implications for Millisecond Pulsar Formation and LIGO

Speaker: Lars Bildsten

Abstract: Most rapidly accreting, weakly magnetic neutron stars in our Galaxy are rotating near 300 Hz. I suggest that these stars rotate fast enough so that, on average, the angular momentum added by accretion is lost to gravitational radiation. The strong spin frequency dependence of the angular momentum loss rate from gravitational radiation then provides a natural reason for similar spin frequencies. Provided that the interior temperature has a large scale asymmetry misaligned from the spin axis, then the temperature sensitive electron captures in the deep crust can provide the required quadrupole. The gravity wave strength is <10-26 from most neutron stars and >2*10-26 for Scorpius X-1. Prior knowledge of the position, spin frequency and orbital periods will allow for deep searches for these periodic signals with gravitational wave interferometers (LIGO, VIRGO and the``dual-recycled'' GEO 600 detector).

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