Observing a Tidal Disruption Event
Abstract
The advent of MAXI and Swift provide the capability to test a physical model for what happens during the tidal-disruption of a star by a super-massive black hole (SMBH). The time evolution of the flares which arise when a star is disrupted by a SMBH are related to the internal density structure of the star. According to recent numerical simulations the standard result that the light curve decays as a power law with index -5/3 only holds at late times. Close to the peak luminosity the light curve is shallower, deviating more strongly from the -5/3 decay for more centrally concentrated (e.g. solar-type) stars. For solar-type stars, the -5/3 factor may only be reached when then luminosity has dropped by a factor of 100. The dependence on stellar structure raises the possibility that the type of star involved can be determined by observing the shape of the light curve. To do this requires two things: (1) a method to find bright tidal disruption candidates close to peak during the disruption and (2) a fast follow-up facility to track the light curve and obtain spectra. The successful launch of the Japanese MAXI instrument provides (1) while Swift is the ideal facility to provide (2). The combination of the two missions will reveal the process of tidal disruption in more detail than has previously been possible.
- Publication:
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AAS/High Energy Astrophysics Division #11
- Pub Date:
- March 2010
- Bibcode:
- 2010HEAD...11.1304O