论文标题
原子气体主导着$ z \ $ z \ 1.3 $的星形星系的重质质量
Atomic Gas Dominates the Baryonic Mass of Star-forming Galaxies at $z \approx 1.3$
论文作者
论文摘要
我们提供了平均原子气体质量，$ \ langle m_ {atom} \ rangle $（包括HI和HE），平均分子气体质量，$ \ langle m_ {mol} \ rangle $和平均星级质量，$ \ langle m _*\ rangle m _*\ rangle $， $ z \ of约0.75-1.45 $，用于探测宇宙中峰值恒星形成活性时期星系的重岩组成。 $ \ langle m_ {atom} \ rangle $ $ $ z = 0.74-1.25 $和$ z = 1.25-1.45 $的两个恒星质量匹配的样品中的星形星系值，是通过在GMRT-cat $ z1 $ z1 $调查中堆叠HI 21cm信号来得出的。我们发现，$ z \ gtrsim 1 $的星形星系的重结构与$ z \ of y of l的重大不同。对于带有$ \ langle m _*\ rangle \ langle \ of10^{10} m_ \ odot $的星形星系，恒星对总baryonic质量的贡献，$ m_ {baryon} $，是$ \％$ \％\％$ z \ z \％$ z \％$ z \ of $ s $ \ y mol $ \ y mor $ \％$ \％$ \ at y mor16 \％， Baryonic质量的$ \ of6 \％$在$ z \ of Yout0 $中，$ \ of 14 \％$在$ z \ of1.3 $中。值得注意的是，我们发现原子气是$ \％的$ \％$ $ m_ {baryon} $，在$ z \ of 1.3 $的星形星系中。我们发现，比例$ \ langle m_ {atom} \ rangle/\ langle m _*\ rangle $在$ z \ of1.0 $和$ z \ th $ z \左右均高于本地宇宙中的比例，均高于本地宇宙，$ \ langle m_ {atom} \ langle m_ {atom} \ rangle} \ langle/\ langle m_* $ z \ of1.0 $，$ \ of 4.4 $在$ z \ of1.3 $，而今天的$ \ of $ \ of $ \ of。此外，我们发现比率$ \ langle m_ {atom} \ rangle/\ langle m_ {mol} \ rangle $ in Star-forming星系中，带有$ \ langle m _*\ langle m _*\ rangle \ rangle \ rangle \ rangle \ rangle \ langle \ langle \ of10^{10} m_ \ odot $ \ odot $ \ y y $ y $ at $ at $ at $ at 2.3 $ at 2. 3.3.3.3 $ z \大约1.3 $。总体而言，我们发现在宇宙中峰值恒星形成活性时期，原子气是$ z \ of $ z \ 3 $的恒星星系的主要成分。
We present a comparison between the average atomic gas mass, $\langle M_{Atom}\rangle$ (including HI and He), the average molecular gas mass, $\langle M_{Mol}\rangle$, and the average stellar mass, $\langle M_*\rangle$, of a sample of star-forming galaxies at $z\approx0.75-1.45$, to probe the baryonic composition of galaxies in and during the epoch of peak star-formation activity in the universe. The $\langle M_{Atom}\rangle$ values of star-forming galaxies in two stellar-mass matched samples at $z=0.74-1.25$ and $z=1.25-1.45$, were derived by stacking their HI 21cm signals in the GMRT-CAT$z1$ survey. We find that the baryonic composition of star-forming galaxies at $z\gtrsim 1$ is dramatically different from that at $z\approx0$. For star-forming galaxies with $\langle M_*\rangle\approx10^{10} M_\odot$, the contribution of stars to the total baryonic mass, $M_{Baryon}$, is $\approx61\%$ at $z\approx0$, but only $\approx16\%$ at $z\approx1.3$, while molecular gas constitutes $\approx6\%$ of the baryonic mass at $z\approx0$, and $\approx14\%$ at $z\approx1.3$. Remarkably, we find that atomic gas makes up $\approx70\%$ of $M_{Baryon}$ in star-forming galaxies at $z\approx1.3$. We find that the ratio $\langle M_{Atom}\rangle/\langle M_*\rangle$ is higher both at $z\approx1.0$ and at $z\approx1.3$ than in the local Universe, with $\langle M_{Atom}\rangle/\langle M_*\rangle\approx1.4$ at $z\approx1.0$, and $\approx4.4$ at $z\approx1.3$, compared to its value of $\approx0.5$ today. Further, we find that the ratio $\langle M_{Atom}\rangle/\langle M_{Mol}\rangle$ in star-forming galaxies with $\langle M_*\rangle \approx10^{10} M_\odot$ is $\approx2.3$ at $z\approx1.0$ and $\approx5.0$ at $z\approx1.3$. Overall, we find that atomic gas is the dominant component of the baryonic mass of star-forming galaxies at $z\approx1.3$, during the epoch of peak star-formation activity in the universe.
