The primary filter for the Roman Galactic Bulge Time Domain Survey, F146, is a very wide filter that extends from ~1-2 microns. The extinction law changes dramatically over this range, so the extinction in the F146 filter for a given star is strongly dependent on its spectrum and the absolute extinction. Galactic models typically apply a constant extinction coefficient using some effective wavelength to scale A_Ks or some other absolute extinction quantity to that of each individual filter. Here, we use model spectra and filter integration to create a more accurate estimate of the extinction coefficient as a function of A_Ks and stellar colors. For convenience we provide corrections the other Roman filters and for both absolute and apparent colors with different observed filter combinations.
This code may be modified to compute corrections for alternate filter sets and/or to use a different extinction law.
extinction_estimator.py provides functions to perform the extinction estimation on simulated or observed colors and A_Ks
ext_utils.py contains the functions used to generate the color and extinction grids from model spectra, perform the fits, and to cleanly format the results
roman_fitting_notebooks contains Jupyter notebooks where the extinction estimator fits were run and diagnostics were plotted
roman_fits_abs_AKs5.json and the other json files hold the results of the fits and get used by extinction_estimator.py