The HI gas fraction scaling relation of the Green Pea galaxies

Author:

Siqi Liu, A-Li Luo, Wei Zhang, Yan-Xia Zhang, Xiao Kong, Yong-Heng Zhao

Keyword:

Astrophysics, Astrophysics of Galaxies, Astrophysics of Galaxies (astro-ph.GA)

journal:

date:

2023-05-08 16:00:00

Abstract

Green Pea galaxies are compact galaxies with high star formation rates. However, limited samples of Green Pea galaxies have HI 21 cm measurements. Whether the HI gas fraction f_{HI} = M_{HI}/M_{*} of Green Pea galaxies follows the existing scaling relations between the f_{HI} and NUV-r color or linear combinations of color and other physical quantities needs checking. Using archival data of HI 21cm observations, we investigate the scaling relation of the NUV-r color with the M_{HI}/M_{*} of 38 Green Pea galaxies, including 17 detections and 21 non-detections. The HI to stellar mass ratios (f_{HI}) of Green Pea galaxies deviate from the polynomial form, where a higher HI gas fraction is predicted given the current NUV-r color, even with the emission lines removed. The blue sources (NUV-r<1) from the comparison sample (ALFALFA-SDSS) follow a similar trend. The HI gas fraction scaling relations with linear combination forms of -0.34(NUV-r) - 0.64 log(mu_{*,z}) + 5.94 and -0.77 log mu_{*,i} + 0.26 log SFR/M_{*}+8.53, better predict the HI gas fraction of the Green Pea galaxies. In order to obtain accurate linear combined forms, higher-resolution photometry from space-based telescopes is needed.

PDF: The HI gas fraction scaling relation of the Green Pea galaxies.pdf