| Description |
An important problem in astrophysics is whether the jet from an accreting black hole is aligned with the black hole spin axis or the accretion disk angular momentum vector. An answer to this question can provide important information about the jet triggering mechanism, disk-jet coupling, and the high energy radiation mechanisms in a black hole system. Tidal Disruption Event (TDE) of a star by a supermassive spinning black hole provides a unique astrophysical laboratory to study the jet alignment through the possibility of jet precession, induced by the Lense-Thirring precession of the disk. In this work, we investigate the Swift XRT light curve of the most well sampled jetted TDE, Swift J1644+57. In the region of the lightcurve where the disk is thick, we estimate, using a known optimistic method and a new conservative method developed by us, the tilt angle of the jet with respect to the black hole spin axis as a function of the black hole spin parameter. We find that the previously reported dips are less likely to be caused by jet precession, i.e., the jet in Swift J1644+57 is more likely to be aligned with the black hole spin axis.
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