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tokens: and 0.4307keV, respectively. If that is indeed the origin of these features, it would be consistent with the presence of strong, highly ionized C and N emission lines in the UV (Cenko etal. 2016 ). Interestingly, Miller etal. ( 2015 ) also suggest several highly ionized emission features are present in their high-resolution spectra, particularly near the O K-edge. Figure 6. Merged X-ray spectra of ASASSN-14li seen at early times (first 200d, black crosses) and later times (after 200d, red crosses). Each spectrum is binned with a minimum of 20 counts per energy bin. The early-time spectrum is best fit with two Gaussian emission features superimposed on a blackbody (black solid line), while the late-time spectrum is consistent with a purely blackbody model (red solid line). The residuals from the fits are shown in the bottom panel. Irrespective of the origin of the emission features, the X-ray emission from ASASSN-14li is reasonably well described by a blackbody. The temperature of the X-ray emission shows only a moderate decrease with time, from 810 5 K down to 4.510 5 K. We also find that between the early- and late-time observations, the mean column density decreases by a factor of 2, becoming comparable to at later times. This could indicate that at early times the material surrounding the TDE was dense, not highly ionized, and obscured the lower energy X-rays, while at late times the material surrounding the event has been nearly completely ionized and thus transparent to the lower energy X-ray photons. We note that the amount of material required to produce this absorbing column is small relative to the overall mass budget, even in the contrived scenario where all of the absorbing material is spherically distributed at the H-emitting radius: M, where f is the covering fraction, r 17 is the characteristic radius of the absorbing material in units of 10 17 cm and N 20 is the hydrogen column density in units of 10 20 cm 2 . Furthermore, our modelling suggests there may be a factor of a few variability in the column density between the individual epochs. Unfortunately the spectra for the individual epochs do not reach the S/N required for a precise determination of the column density. We also note similar variability and overall decrease in the absorbing column in the eight temporally binned spectra. The moderately decreasing temperature and variability in the column density are similar to the findings from Miller etal. ( 2015 ), but we have increased the temporal baseline by a factor of 3. Finally, we note that the Swift XRT detector lacks the energy coverage to discriminate between a bremsstrahlung and blackbody spectrum. While we have assumed the X-ray emission to be well described as a blackbody, there is only marginal evidence that the X-ray spectrum turns over at lower energies. It is plausible that the X-ray emission arises from tidal debris shocking the ambient medium in the vicinity of the SMBH. For ionized gas in the strong shock