摘要: The atomic-to-molecular gas conversion is a critical step in the baryon cycle
of galaxies, which sets the initial conditions for subsequent star formation
and influences the multi-phase interstellar medium. We compiled a sample of 94
nearby galaxies with observations of multi-phase gas contents by utilizing
public H I, CO, and optical IFU data from the MaNGA survey together with new
FAST H I observations. In agreement with previous results, our sample shows
that the global molecular-to-atomic gas ratio ($R_{\rm mol} \equiv$ log $M_{\rm
H_2}/M_{\rm H\ I}$) is correlated with the global stellar mass surface density
$\mu_*$ with a Kendall's $\tau$ coefficient of 0.25 and $p < 10^{-3}$, less
tightly but still correlated with stellar mass and NUV$-$ r color, and not
related to the specific star formation rate (sSFR). The cold gas distribution
and kinematics inferred from the H I and CO global profile asymmetry and shape
do not significantly rely on $R_{\rm mol}$. Thanks to the availability of
kpc-scale observations of MaNGA, we decompose galaxies into H II, composite,
and AGN-dominated regions by using the BPT diagrams. With increasing $R_{\rm
mol}$, the fraction of H II regions within 1.5 effective radius decreases
slightly; the density distribution in the spatially resolved BPT diagram also
changes significantly, suggesting changes in metallicity and ionization states.
Galaxies with high $R_{\rm mol}$ tend to have high oxygen abundance, both at
one effective radius with a Kendall's $\tau$ coefficient of 0.37 ($p <
10^{-3}$) and their central regions. Among all parameters investigated here,
the oxygen abundance at one effective radius has the strongest relation with
global $R_{\rm mol}$, but the dependence of gas conversion on gas distribution
and galaxy ionization states is weak.
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来自:
余捻坤
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分类:
天文学
>>
天文学
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说明:
Accepted by SCPMA. We sincerely appreciate the constructive
suggestions and comments from Lihwai Lin
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引用:
ChinaXiv:202404.00065
(或此版本
ChinaXiv:202404.00065V1)
DOI:10.12074/202404.00065V1
CSTR:32003.36.ChinaXiv.202404.00065.V1
- 推荐引用方式:
Niankun Yu,Zheng Zheng,Chao-Wei Tsai,Pei Zuo,Sara L. Ellison,David V. Stark,Di Li,Jingwen Wu,Karen L. Masters,Ting Xiao,Yinghui Zheng,Zongnan Li,Kai Zhang,Hongying Chen,Shu Liu,Sihan Jiao,Fanyi Meng.(2024).The ALMaQUEST Survey XV: The Dependence of the Molecular-to-Atomic Gas
Ratios on Resolved Optical Diagnostics.中国科学院科技论文预发布平台.[ChinaXiv:202404.00065]
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