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One of the main challenges of current tidal disruption events (TDEs) studiesis that emission arising from AGN activity may potentially mimic the expectedX-ray emission of a TDE. Here we compare the X-ray properties of TDEs and AGNto determine a set of characteristics which would allow us to discriminatebetween flares arising from these two objects. We find that at peak, TDEs arebrighter than AGN found at similar redshifts. However, compared to preflareupperlimits, highly variable AGN can produce flares of a similar order ofmagnitude as those seen from X-ray TDEs. Nevertheless, TDEs decay significantlymore monotonically, and their emission exhibits little variation in spectralhardness as a function of time. We also find that X-ray TDEs are less absorbed,and their emission is much softer than the emission detected from AGN found atsimilar redshifts. We derive the X-ray luminosity function (LF) for X-ray TDEsusing the events from Auchettl et al. (2017). Interestingly, our X-ray LFmatches closely the theoretically derived LF by Milosavljevi\'c et al. (2006).which assumes a higher TDE rate currently estimated from observations. Usingour results and the results of Stone & Metzger (2016), we estimate a TDE rateof $(0.7-4.7)\times10^{-4}$ yr$^{-1}$ per galaxy, higher than currentobservational estimates. We find that TDEs can contribute significantly to theLF of AGN for $z\lesssim0.4$, while there is no evidence that TDEs influencethe growth of $10^{6-7}M_{\odot}$ BHs. However, BHs $<10^{6}M_{\odot}$ can growfrom TDEs arising from super-Eddington accretion without contributingsignificantly to the observed AGN LF at $z=0$.

Comparison of the X-ray emission from Tidal Disruption Events with those of Active Galactic Nuclei