Authors: Louis J. Rubbo, Kelly Holley-Bockelmann, Lee Samuel Finn Date: Mon, 20 Feb 2006 Abstract: Stellar mass compact objects in short period orbits about a $10ˆ{4.5}$--$10ˆ{7.5}$ solar mass massive black hole (MBH) are thought to be a significant continuous-wave source of gravitational radiation for the ESA/NASA Laser Interferometer Space Antenna (LISA) gravitational wave detector. However, these extreme mass-ratio inspiral sources began in long-period, nearly parabolic orbits that have multiple close encounters with the MBH. The gravitational radiation emitted during these close encounters may be detectable by LISA as a gravitational wave burst if the characteristic passage timescale is less than $10ˆ5$ seconds. Scaling a static, spherical model to the size and mass of the Milky Way bulge we estimate an event rate of ~ 15 per year for such burst signals, detectable by LISA with signal-to-noise greater than five, originating in our galaxy. When extended to include Virgo cluster galaxies our estimate increases to a gravitational wave burst rate of ~ 18. We conclude that these extreme mass-ratio burst sources may be a steady and significant source of gravitational radiation in the LISA data streams. |
0602445
(/preprints/astro-ph)
2006-02-23, 08:40
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