Leader: Kyuseok Oh

Email: oh@kasi.re.kr

Collaborators: Jiwon Chung, Hyunjin Jeong, Jong Chul Lee, Joon Hyeop Lee, Mina Pak (and anyone interested in the project is of course welcome to join.)

Topic: The unexpected dynamics of low-mass dwarf galaxies

Status: under review by Science Committee

Abstract: Previous studies searching for black hole activity (so called, active galactic nuclei (AGNs)) in dwarf galaxies have been relied on spectroscopic observations of the galactic center using single-fiber instrument (e.g., the Sloan Digital Sky Survey). Prominent emission-lines and its ratios let us know origin of primary ionizing source distinguishing central nuclear activity from star formation, vice versa. Despite its efficiency as a useful diagnostic tool, single-fiber spectroscopic observations can miss AGN signatures due to various reasons: a) active star formation occurring in the galaxy center, b) off-centered AGN due to galaxy merger, c) switched-off AGN echoing its AGN signatures at large distances from the galaxy center, d) strong host galaxy light that dilutes apparent AGN signals. With the recent advent of integral-field unit (IFU) spectroscopic surveys, such as Hector galaxy survey, it is now possible to study AGN populations in dwarf galaxies that are less biased to central luminosity, star formation, and host galaxy light. In this project, we aim to study AGNs in dwarf galaxies by utilizing spatially resolved emission line diagnostic diagrams. We will investigate not only the demographics of actively-accreting systems in dwarf galaxies which could host the seed black holes that did not grow enough to be supermassive, but also the scaling relations in the low-mass end adding to the existing several tens of intermediate mass black holes (IMBH).

Needed data products: flux calibrated spectrum at each spaxel

Publication Date: 30/06/2023