One of the puzzles associated with tidal disruption event candidates ( TDEs ) is that there is a dichotomy between the color temperatures of { few } \times 10 ^ { 4 } K for TDEs discovered with optical and UV telescopes , and the color temperatures of { few } \times 10 ^ { 5 } -10 ^ { 6 } K for TDEs discovered with X-ray satellites .
Here we propose that high-temperature TDEs are produced when the tidal debris of a disrupted star self-intersects relatively close to the supermassive black hole , in contrast to the more distant self-intersection that leads to lower color temperatures .
In particular , we note from simple ballistic considerations that greater apsidal precession in an orbit is the key to closer self-intersection .
Thus larger values of \beta , the ratio of the tidal radius to the pericenter distance of the initial orbit , are more likely to lead to higher temperatures of more compact disks which are super-Eddington and geometrically and optically thick .
For a given star and \beta , apsidal precession also increases for larger black hole masses , but larger black hole masses imply a lower temperature at the Eddington luminosity .
Thus the expected dependence 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 plunging stellar orbit with \beta > 3 is needed and a black hole mass of \lesssim 5 \times 10 ^ { 6 } M _ { \odot } is favored .
Although observations of TDEs are comparatively scarce and are likely dominated by selection effects , it is encouraging that both expectations are consistent with current data .