论文标题
灰尘，CO和[CI]：在宇宙时间富含金属星系中分子气体示踪剂的交叉校准
Dust, CO and [CI]: Cross-calibration of molecular gas mass tracers in metal-rich galaxies across cosmic time
论文作者
论文摘要
我们提出了星系中三个主要分子气体示踪剂的自洽交叉校准，$ \ rm^{12} co $ $（1-0），[ci]（$^3p_1 $ - $ - $ - $ - $^3p_0 $）线条，使用smbsm duck insission，使用407 Galaxies to smer to smer to smerges to smer to smerge最多$ z \大约6 $。一种贝叶斯方法用于生成这些分子气体指示器的星系尺度通用校准，该校准的数量超过3-4个数量级，红外发光度，$ l _ {\ rm ir} $。关于尘埃连续，我们使用大量加权的尘埃温度，$ t _ {\ rm mw} $，使用温度和光度之间的新经验关系确定。我们发现平均$ l/m _ {\ rm mol} $气体质量转换因子为$α_{850} = 6.9 \ times10^{12} \，\ rm w \，hz^{ - 1}} { - 1}} 4 \，m _ {\ odot}（k \，km \，s^{ - 1} \，pc^2）^{ - 1} $和$α_ {\ rm ci} = \ rm 17.0 \ （k \，km \，s^{ - 1} \，pc^2）^{ - 1} $，基于以下假设：样品的平均灰尘特性（$κ_H$ =气盘/灰尘比率/灰尘比率）与本地金属富金属元素和MW相似。固有散射最小的示踪剂是[CI]（1-0），而CO（1-0）的示踪剂最高。转换因子与$ l _ {\ rm ir} $较弱但显着相关。假设富含金属的星系的粉尘特性，我们推断出中性碳丰度$ x _ {\ rm ci} = [c^0/\ rm mol] = 1.6 \ times 10^{ - 5} $，类似于MW中的中性碳。我们没有发现在主序列（MS）星系和具有极端恒星形成强度的$α_ {\ rm co} $的双峰性的证据，即ULIRGS和SMG。发现三个转换因子的平均值在MS星系和ULIRGS/SMG之间相似，达到10-20％以内。我们表明，对于金属丰富的星系，$α_ {\ rm co} $，$ x _ {\ rm ci} $和$κ_H$的接近宇宙平均值足以满足全球分子气体估计。
We present a self-consistent cross-calibration of the three main molecular gas mass tracers in galaxies, the $\rm ^{12}CO$(1-0), [CI]($^3P_1$-$^3P_0$) lines, and the submm dust continuum emission, using a sample of 407 galaxies, ranging from local disks to submillimetre-selected galaxies (SMGs) up to $z \approx 6$. A Bayesian method is used to produce galaxy-scale universal calibrations of these molecular gas indicators, that hold over 3-4 orders of magnitude in infrared luminosity, $L_{\rm IR}$. Regarding the dust continuum, we use a mass-weighted dust temperature, $T_{\rm mw}$, determined using new empirical relations between temperature and luminosity. We find the average $L/M_{\rm mol}$ gas mass conversion factors to be $α_{850}= 6.9\times10^{12}\,\rm W\,Hz^{-1}\,M_{\odot}^{-1}$, $α_{\rm CO} = \rm 4\,M_{\odot} (K\,km\,s^{-1}\,pc^2)^{-1}$ and $α_{\rm CI} = \rm 17.0 \,M_{\odot} (K\,km\,s^{-1}\,pc^2)^{-1}$, based on the assumption that the mean dust properties of the sample ($κ_H$ = gas-to-dust ratio/dust emissivity) will be similar to those of local metal rich galaxies and the MW. The tracer with the least intrinsic scatter is [CI](1-0), while CO(1-0) has the highest. The conversion factors show a weak but significant correlation with $L_{\rm IR}$. Assuming dust properties typical of metal-rich galaxies, we infer a neutral carbon abundance $X_{\rm CI} = [C^0/\rm mol]=1.6\times 10^{-5}$, similar to that in the MW. We find no evidence for bimodality of $α_{\rm CO}$ between main-sequence (MS) galaxies and those with extreme star-formation intensity, i.e. ULIRGs and SMGs. The means of the three conversion factors are found to be similar between MS galaxies and ULIRGs/SMGs, to within 10-20%. We show that for metal-rich galaxies, near-universal average values for $α_{\rm CO}$, $X_{\rm CI}$ and $κ_H$ are adequate for global molecular gas estimates.
