and correlations between TDE and host galaxy properties. In this paper, we analyse a rich dataset for AT2019qiz including densely sampled spectroscopy, very early and late photometric observations, and the first detection of the source in X-rays. We also examine the host galaxy in detail. While we link the optical properties of the TDE to its behaviour in the radio, the full radio dataset and analysis will be presented in a companion paper (K. D. Alexander et al., in preparation).

Observations {#sec:obs}
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Ground-based imaging {#sec:ground}
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Well-sampled host-subtracted light curves of AT2019qiz were obtained by the ZTF public survey, in the $g$ and $r$ bands, and ATLAS in the $c$ and $o$ bands (effective wavelengths 5330 and 6790Å). The ZTF light curves were accessed using the Lasair alert broker[^5] [@Smith2019].

We triggered additional imaging with a typical cadence of four days in the $g,r,i$ bands using the Las Cumbres Observatory (LCO) global network of 1-m telescopes [@Brown2013]. We retrieved the reduced (de-biased and flat-fielded) images from LCO and carried out point spread function (PSF) fitting photometry using a custom wrapper for <span style="font-variant:small-caps;">daophot</span>. The zeropoint in each image was calculated by comparing the instrumental magnitudes of field stars with 