The Prospects of Observing Tidal Disruption Events with the Large Synoptic Survey Telescope

Abstract

Abstract The upcoming Large Synoptic Survey Telescope (LSST) will observe 18,000 deg2 of the southern sky and is expected to discover thousands of transients every night due to its large coverage area and its observing strategy. In this work, we address the prospects for the LSST in discovering tidal disruption events (TDEs) and in probing the supermassive black hole (SMBH) mass distribution in the universe. We used the LSST simulation framework and defined TDE catalogs on 20 fields of 20.25 deg2 size. TDE properties were defined by randomly chosen impact factors and SMBH masses drawn from six different mass distributions. Observations of TDEs over 10 years of LSST operation were simulated by querying the simulated observing strategy database minion_1016. Based on the results of our simulations, we estimate that the LSST should discover between 35,000 and 80,000 TDEs in 10 years of operation, depending on the assumed SMBH mass distribution. We also find that probing the SMBH mass distribution with TDE observations will not be straightforward, due to the fact that TDEs caused by low-mass black holes (105 M ⊙) are expected to be less luminous and shorter than TDEs by heavier SMBHs (> 106 M ⊙), and therefore will mostly be missed by the irregular LSST cadence minion_1016.