AspGap: Augmented Stellar Parameters and Abundances for 24 million RGB stars from Gaia XP

AspGap is a novel data-driven model to perform regressions with the XP spectra, augmented by transfer learning from high-resolution APOGEE spectra. Using a training set of stellar labels from APOGEE, we demonstrate that AspGap can deliver effective temperature, surface gravity, metallicity, and alpha abundance to accuracies of ~ 1%, 0.15 dex, 0.07 dex, and 0.03 dex, respectively. See the paper for more details. In version 3.2, the catalog includes radial velocity measurements by Gaia (~ 12 million), and distances are obtained by cross-matching with Bailer-Jones+ (2021) for user-friendly access. The AspGap labels are introduced in our paper, and the 6-D coordinates (x, y, z, vx, vy, vz) are calculated using astropy.coord.galactocentric_frame_defaults.set('v4.0') The following code provides a recommended way to easily read the catalog: <pre><code class="language-python">import vaex cat = vaex.open("JDrgb_12m_v3_3_6dBJ.hdf5") # if you work with astropy.table tab_astropy = cat.to_astropy_table() # or pd.DataFrame ... tab_df = cat.to_pandas_df()</code></pre>