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Creators/Authors contains: "Kumah, Angela"

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  1. Abstract A star completely destroyed in a tidal disruption event (TDE) ignites a luminous flare that is powered by the fallback of tidally stripped debris to a supermassive black hole (SMBH) of massM. We analyze two estimates for the peak fallback rate in a TDE, one being the “frozen-in” model, which predicts a strong dependence of the time to peak fallback rate,tpeak, on both stellar mass and age, with 15 days ≲tpeak≲ 10 yr for main sequence stars with masses 0.2 ≤M/M≤ 5 andM= 106M. The second estimate, which postulates that the star is completely destroyed when tides dominate the maximum stellar self-gravity, predicts thattpeakis very weakly dependent on stellar type, with t peak = 23.2 ± 4.0 days M / 10 6 M 1 / 2 for 0.2 ≤M/M≤ 5, while t peak = 29.8 ± 3.6 days M / 10 6 M 1 / 2 for a Kroupa initial mass function truncated at 1.5M. This second estimate also agrees closely with hydrodynamical simulations, while the frozen-in model is discrepant by orders of magnitude. We conclude that (1) the time to peak luminosity in complete TDEs is almost exclusively determined by SMBH mass, and (2) massive-star TDEs power the largest accretion luminosities. Consequently, (a) decades-long extra-galactic outbursts cannot be powered by complete TDEs, including massive-star disruptions, and (b) the most highly super-Eddington TDEs are powered by the complete disruption of massive stars, which—if responsible for producing jetted TDEs—would explain the rarity of jetted TDEs and their preference for young and star-forming host galaxies. 
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