论文标题
阿尔玛叛军调查：$ z \ sim 7 $ lyman破裂星系的灰尘内容
The ALMA REBELS Survey: the dust content of $z \sim 7$ Lyman Break Galaxies
论文作者
论文摘要
我们包括将金属和灰尘富集的完全耦合处理到星系组的Delphi半分析模型中，以解释Atacama大毫米阵列（Alma）Rebels大型程序在$ Z \ Simeq 7 $上检测到的13个Lyman Break Galaxies（LBG）的灰尘含量。我们发现，银河尘埃质量（$ m_d $）受SNII尘埃生产，倍增，冲击破坏和流出中的弹射的结合。谷物生长（具有标准的时间尺度$τ_0= 30 $ MYR）扮演的角色可以忽略不计。该模型预测$ \ sim 0.07-0.1 \％$和UV-TOT-TOTAL恒星形成速率的关系的尘埃与星形质量比，以至于$ log（ψ_{ψ_{\ rm uv}）= -0.05〜 [log（log（log（ψ）]对于带有恒星质量$ m_* = 10^{9-10} m_ \ odot $的叛军星系的模糊）。这种关系将LBG的固有紫外线光度与观察到的亮度函数在$ z = 7 $相结合。但是，在13个系统中，有2个显示出尘埃与星的质量比（$ \ sim 0.94-1.1 \％$），其$ 18 \ times $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $。由于灰尘和金属富集之间的物理耦合，甚至将$τ_0$降低到非常低的值（0.3 Myr），只会将灰尘与恒星质量比增加一个因子$ \ sim 2 $。鉴于谷物的生长对于如此高的尘埃与恒星质量比率不是可行的解释，我们提出了替代溶液。
We include a fully coupled treatment of metal and dust enrichment into the Delphi semi-analytic model of galaxy formation to explain the dust content of 13 Lyman Break Galaxies (LBGs) detected by the Atacama Large millimetre Array (ALMA) REBELS Large Program at $z\simeq 7$. We find that the galaxy dust mass, $M_d$, is regulated by the combination of SNII dust production, astration, shock destruction, and ejection in outflows; grain growth (with a standard timescale $τ_0= 30$ Myr) plays a negligible role. The model predicts a dust-to-stellar mass ratio of $\sim 0.07-0.1\%$ and a UV-to-total star formation rate relation such that $log (ψ_{\rm UV}) = -0.05 ~[log (ψ)]^{2} + 0.86 ~log(ψ) -0.05$ (implying that 55-80\% of the star formation is obscured) for REBELS galaxies with stellar mass $M_* = 10^{9-10} M_\odot$. This relation reconciles the intrinsic UV luminosity of LBGs with their observed luminosity function at $z=7$. However, 2 out of the 13 systems show dust-to-stellar mass ratios ($\sim 0.94-1.1\%$) that are up to $18\times$ larger than expected from the fiducial relation. Due to the physical coupling between dust and metal enrichment, even decreasing $τ_0$ to very low values (0.3 Myr) only increases the dust-to-stellar mass ratio by a factor $ \sim 2$. Given that grain growth is not a viable explanation for such high observed ratios of the dust-to-stellar mass, we propose alternative solutions.
