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arXiv · 2305.05167

The HI gas fraction scaling relation of the Green Pea galaxies

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

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Siqi Liu, A-Li Luo, Wei Zhang, Yan-Xia Zhang, Xiao Kong, Yong-Heng Zhao. 2023-05-09. The HI gas fraction scaling relation of the Green Pea galaxies. https://doi.org/10.1088/1674-4527%2Faccb78

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