论文标题
高红移星系的星际介质：来自C III的收集线索]和[C II]线
The interstellar medium of high-redshift galaxies: Gathering clues from C III] and [C II] lines
论文作者
论文摘要
对于局部星系，已经观察到[C II]线的光度与恒星形成速率（SFR）之间的紧密关系。在高红移（z> 5）上，星系与本地$σ$ _ [c ii] - $σ$ _SFR关系偏下。这种偏差可能是由于早期星系中星系中不同星际培养基（ISM）特性引起的。为了检验这一假设，我们将[C II]和SFR数据与C III]线观测以及我们的物理模型相结合。我们还研究了ISM属性，例如爆发，$κ_s$，总气体密度，$ n $和金属性，$ z $，会影响与$σ$ _ [c ii] - $σ$ _SFR关系的偏差。 We present the VLT/X-SHOOTER observations targeting the C III] $λ1909$ line emission in three galaxies at 5.5 < z < 7. We include X-SHOOTER and VLT/MUSE archival data of eight galaxies at 2 < z < 7, and eleven star-forming systems at 6 < z < 7.5, with either C III] or [C II] detection reported in the literature.我们检测到CIII] $ λλ1907，1909 $在HZ10中排放，我们得出了C III] $λ1909$线的内在，集成的通量。通过应用基于MCMC算法的有力动机的模型，我们限制了我们的星系样本，$κ_s$，$ n $和$ z $的ISM属性。在大多数情况下，高Z形成星系显示出生产金属度。大多数来源都有$ log（κ_s）> 1 $，也就是说，它们超过了Kennicutt-Schmidt（KS）的关系，大约是一个数量级，这意味着整个KS关系可能在早期就向上移动。此外，我们样本的所有高Z星系都位于$σ$ _ [c ii] - $σ$ _SFR本地关系之下。总的气体密度为$ n $，与与本地$σ$ _ [c ii] - $σ$ _SFR关系的偏差最密切相关。
A tight relation between [C II] line luminosity and the star formation rate (SFR) has been observed for local galaxies. At high redshift (z > 5), galaxies instead deviate downwards from the local $Σ$_[C II] - $Σ$_SFR relation. This deviation might be caused by different interstellar medium (ISM) properties in galaxies at early epochs. To test this hypothesis, we combined the [C II] and SFR data with C III] line observations and our physical models. We additionally investigated how ISM properties, such as burstiness, $κ_s$, total gas density, $n$, and metallicity, $Z$, affect the deviation from the $Σ$_[C II] - $Σ$_SFR relation in these sources. We present the VLT/X-SHOOTER observations targeting the C III] $λ1909$ line emission in three galaxies at 5.5 < z < 7. We include X-SHOOTER and VLT/MUSE archival data of eight galaxies at 2 < z < 7, and eleven star-forming systems at 6 < z < 7.5, with either C III] or [C II] detection reported in the literature. We detected C III] $λλ1907, 1909$ line emission in HZ10 and we derived the intrinsic, integrated flux of the C III] $λ1909$ line. We constrained the ISM properties for our sample of galaxies, $κ_s$ , $n$, and $Z$, by applying our physically motivated model based on the MCMC algorithm. For the most part, high-z star-forming galaxies show subsolar metallicities. The majority of the sources have $log(κ_s) > 1$, that is, they overshoot the Kennicutt-Schmidt (KS) relation by about one order of magnitude, implying that the whole KS relation might be shifted upwards at early times. Furthermore, all the high-z galaxies of our sample lie below the $Σ$_[C II] - $Σ$_SFR local relation. The total gas density, $n$, shows the strongest correlation with the deviation from the local $Σ$_[C II] - $Σ$_SFR relation.
