A versatile classification tool for galactic activity using optical and infrared colors [GA]

http://arxiv.org/abs/2303.11691


We use the Random Forest (RF) algorithm to develop a tool for automated activity classification of galaxies into 5 different classes: Star-forming (SF), AGN, LINER, Composite, and Passive. We train the algorithm on a combination of mid-IR (WISE) and optical photometric data while the true labels (activity classes) are based on emission line ratios. Our classifier is built to be redshift-agnostic and it is applicable to objects up to z $\sim$0.1. It reaches a completeness $>$80 % for SF and Passive galaxies, and $\sim$60 % for AGN. Applying it to an all-sky galaxy catalog (HECATE) reveals a large population of low-luminosity AGNs outside the AGN locus in the standard mid-IR diagnostics.

Read this paper on arXiv…

E. Kyritsis, C. Daoutis, A. Zezas, et. al.
Wed, 22 Mar 23
25/68

Comments: 3 pages, 3 figures, the manuscript will be published on Memorie della SAIt