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.
Disentangling the influence of the host galaxy in quasar spectra
Spectral properties and H and Hbeta indices for quasars in DR20 to disentangle the AGN-host galaxy contribution
Catalog Data
Abstract
This value added catalog contains the quasar properties presented in Negrete et al. (2025) to disentangle the contribution of the active galactic nucleus (AGN) from the host galaxy contribution to the observed spectrum. This VAC consists of two tables. The first one includes the delivered catalog comprising 28 parameters for 3,082 quasars, with a single row per object. Each object can be identified using the RA and DEC coordinates. Details of the sample selection and performed analysis are described in Negrete et al. (2025). The second table contains the measurements of the CaII-H and Hb indices for 6,439 quasars in the DR20 sample, selected by having 0.01 < z < 0.8, SN_MEDIAN_ALL > 15, FIRSTCARTON containing 'bhm' in the label, and CLASS = QSO.
Catalog last modified: 2026-07-30 12:12:10