2024/02/08 by Xueguang Zhang, Zhang, XueGuang
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics of Galaxies (astro-ph.GA) #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena #Stellar, planetary, and galactic studies
paper · pdf · doi:10.48550/arxiv.2402.05365
openalex publication_date 2024/02/08 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
In this manuscript, clues are provided to support globally negative AGN feedback on star formation in the host galaxies of the local low-redshift SDSS Type-2 AGN, based on the different dependence of narrow Hα line luminosity LHα on optical continuum luminosity λLcont between the starforming galaxies and the Type-2 AGN. Through the measured LHα and λLcont in SDSS starforming galaxies, there is a strong linear correlation between λLcont and LHα, accepted as a standard correlation without effects of AGN activity. Meanwhile, considering apparent contributions of AGN activity to narrow Hα line emissions in the Type-2 AGN, the correlation between λLcont and LHα in the SDSS Type-2 AGN leads to statistically lower LHα in the Type-2 AGN than in the starforming galaxies, with significance level higher than 5σ, even after considering necessary effects (including effects of host galaxy properties), leading to accepted conclusion on the globally negative AGN feedback in the local Type-2 AGN. Meanwhile, properties of Dn(4000) and HδA can provide indirect clues to support the globally negative AGN feedback in the local Type-2 AGN, due to older stellar ages in the Type-2 AGN. Moreover, it is interesting to expect more than 50% narrow Hα emissions globally suppressed in the host galaxies of the Type-2 AGN relative to the starforming galaxies. The results not only support globally negative AGN feedback in the local Type-2 AGN, but also show further clues on the quantification of suppressions of star formation by the globally negative AGN feedback.