In addition to the primary SDSS photometry and spectroscopy, there are a few extra catalogs created by our collaborators that are distributed through the SAS. These Value-Added Catalogs (VACs) are listed below, and include catalogs that were released in earlier data releases.
SDSS-V/BOSS DR20 Catalogue of Galactic Orbital Elements
Catalogue of orbital parameters for over 1.5 million stars in DR20, from the Galactic dynamics framework GravPot16.
Catalog Data
Abstract
This value added catalog provides a homogeneous entry for every star observed by the SDSS-V/BOSS survey in both the northern and southern hemispheres that has a counterpart in the Gaia DR3 catalog. The VAC includes a comprehensive set of stellar parameters and, in particular, precise Galactic orbital elements derived for each source, using the GravPot16 framework, described in Fernández-Trincado et al. (2020). The VAC will be fully described in Fernández-Trincado (in preparation). Stellar orbits were integrated in a non-axisymmetric Galactic potential that includes a realistic (as far as possible) Galactic bar, using the GravPot16 galaxy modeling code. This code follows the mass-density profiles of the Besan Galaxy Model (see Robin et al. 2003; 2012; 2014), and incorporates the most up-to-date structural and dynamical constraints available for the Milky Way. For each star, we employed a Monte Carlo approach consisting of 500,000 orbital realizations to properly propagate the observational uncertainties. Initial conditions were constructed by sampling the radial velocities from SDSS-V DR20, the absolute proper motions from Gaia DR3,, and the heliocentric distances from SDSS-V DR20. This procedure allowed us to quantify the impact of measurement errors on the derived orbital properties and to assess the influence of the Galactic bar on the stellar orbits. From these realizations, we computed key orbital parameters for each star, including the orbital eccentricity, apogalactocentric and perigalactocentric distances, maximum vertical excursions from the Galactic plane, the angular momentum vector, the specific orbital energy and the Jacobi constant in the reference frame where the bar is at rest. For reference, we used the solar position R= 8.178 kpc, and Z = 25 pc, and solar motion of [U,V,W] = [11.10, 248.5, 7.25] km/s. We assumed a bar angle of 20 degrees, and a bar mass of 11 billions Solar mass. For each star, the VAC provides the median values and associated statistics derived from half-millions representative orbital ensembles integrated over a 3 Gyr timespan. Orbits were computed with a “boxy/peanut” bar structure with a patterns speed of 41 +/- 10 km/s/kpc.
Catalog last modified: 2026-07-30 12:12:10