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One of the puzzles associated with tidal disruption event candidates (TDEs)is that there is a dichotomy between the color temperatures of ${\rm few}\times10^4$~K for TDEs discovered with optical and UV telescopes, and the colortemperatures of ${\rm few}\times 10^5 - 10^6$~K for TDEs discovered with X-raysatellites. Here we propose that high-temperature TDEs are produced when thetidal debris of a disrupted star self-intersects relatively close to thesupermassive black hole, in contrast to the more distant self-intersection thatleads to lower color temperatures. In particular, we note from simple ballisticconsiderations that greater apsidal precession in an orbit is the key to closerself-intersection. Thus larger values of $\beta$, the ratio of the tidal radiusto the pericenter distance of the initial orbit, are more likely to lead tohigher temperatures of more compact disks which are super-Eddington andgeometrically and optically thick. For a given star and $\beta$, apsidalprecession also increases for larger black hole masses, but larger black holemasses imply a lower temperature at the Eddington luminosity. Thus the expecteddependence of the temperature on the mass of the black hole is non-monotonic.We find that in order to produce a soft X-ray temperature TDE, a deep plungingstellar orbit with $\beta> 3$ is needed and a black hole mass of $\lesssim5\times 10^6 M_\odot$ is favored. Although observations of TDEs arecomparatively scarce and are likely dominated by selection effects, it isencouraging that both expectations are consistent with current data.

Soft X-ray Temperature Tidal Disruption Events from Stars on Deep Plunging Orbits