Photometric and Astrometric Determinations of Effective Temperature and Surface Gravity for the White Dwarfs in HETDEX

In this talk, we will describe our determinations for the photospheric parameters (effective temperature and surface gravity) for the white dwarf stars observed with the HET Dark Energy Experiment (HETDEX). We used the colors u, g, r, i, and z from the Sloan Digital Sky Survey (SDSS) and astrometry and photometry data from the Gaia mission and compared them with photometric models. Our independent determinations are then compared to the results from spectroscopic fits. Despite fitting much less data points in comparison with spectroscopy, our determinations are fundamental to distinguish between hot and cold solutions from line fitting techniques. Our results are not plagued by the intrinsic problem of spectroscopic flux calibration in the ultraviolet range due to Earth's atmosphere, and can even constrain the photospheric parameters when fitting white dwarf stars with infrared excess (possibly due to a companion).