point source. We find visibly smoother residuals in this case.[]{data-label="fig:galfit"}](galfit.pdf){width="\columnwidth"}

Velocity dispersion and black hole mass
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Following @Wevers2017 [@Wevers2019], we fit the velocity dispersion of stellar absorption lines with the code <span style="font-variant:small-caps;">ppxf</span> [@Cappellari2017] to estimate the mass of the central SMBH. We use a late-time spectrum obtained from X-shooter, resampled to a logarithmic spacing in wavelength and with the continuum removed via polynomial fits. We find a dispersion $\sigma=69.7\pm2.3$kms$^{-1}$.

Using relations between velocity dispersion and black hole mass (the $M_\bullet-\sigma$ relation), this gives a SMBH mass $\log (M_\bullet/M_\odot)=5.75\pm0.45$ in the calibration of @McConnell2013, or $\log (M_\bullet/M_\odot)=6.52\pm0.34$ in the calibration of @Kormendy2013. The calibration of @Gultekin2009 gives an intermediate value $\log (M_\bullet/M_\odot)=6.18\pm0.44$. The reason for the large spread in these estimates is that these relations were calibrated based on samples that comprised mostly black holes more massive than $10^7$. However, the estimates here are consistent, within the errors, with an independent mass measurement based on the TDE light curve (section \[sec:phot\]).

Host SED model
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Archival photometry of this galaxy is available from the PanSTARRS catalog in the $g,r,i,z,y$ filters, as well as in data releases from the 2 Micron All Sky Survey [2MASS; @Skrutskie2006] in the $J,H,K$ filters 