论文标题
从爆发指示器的固有散射中改进了星系星形成随机性
Improved Measurements of Galaxy Star Formation Stochasticity from the Intrinsic Scatter of Burst Indicators
论文作者
论文摘要
短期刻度恒星形成变化（即“爆发”）的测量是我们对星系中星系中恒星形成反馈机制和恒星种群组装的理解不可或缺的一部分。我们扩展了Broussard等人的工作。 （2019年）通过引入对星系星形形成的新分析，该分析解释了$ q_ {sg} = \ mathrm {e（b-v）_ {star}}/\ mathrm {e（b-v）_ {b-v）_ {als}} $分布，一个主要的混乱因素。 We use Balmer decrements from the MOSFIRE Deep Evolution Field (MOSDEF) survey to measure $Q_{sg}$, which we use to construct mock catalogs from the Santa Cruz Semi-Analytic Models and Mufasa cosmological hydrodynamical simulation based on 3D-HST, Fiber Multi-Object Spectrograph (FMOS)-COSMOS, and MOSDEF galaxies with H$α$ detections.使用突发指示器$η= \ log_ {10}（\ Mathrm {sfr_ {sfr_ {hα}/sfr_ {nuv}}）$将模拟目录的结果与$η$分布的标准偏差表示表明爆发的标准偏差。我们发现模拟和观察到的$η$分配形状之间的体面协议；但是，与观察值相比，FMOS-COSMOS和MOSDEF模拟模拟显示出系统低的中位数，并散布在$η$中。这项工作还提出了分析的新方法，该方法得出了$η$中固有散布之间的关系，通过测量不确定性添加的散射和观察到的散射，导致固有的爆发度测量值为$ 0.06-0.16 $ dex。
Measurements of short-timescale star formation variations (i.e., "burstiness") are integral to our understanding of star formation feedback mechanisms and the assembly of stellar populations in galaxies. We expand upon the work of Broussard et al. (2019) by introducing a new analysis of galaxy star formation burstiness that accounts for variations in the $Q_{sg}=\mathrm{E(B-V)_{stars}}/\mathrm{E(B-V)_{gas}}$ distribution, a major confounding factor. We use Balmer decrements from the MOSFIRE Deep Evolution Field (MOSDEF) survey to measure $Q_{sg}$, which we use to construct mock catalogs from the Santa Cruz Semi-Analytic Models and Mufasa cosmological hydrodynamical simulation based on 3D-HST, Fiber Multi-Object Spectrograph (FMOS)-COSMOS, and MOSDEF galaxies with H$α$ detections. The results of the mock catalogs are compared against observations using the burst indicator $η= \log_{10}(\mathrm{SFR_{Hα}/SFR_{NUV}})$, with the standard deviation of the $η$ distribution indicating burstiness. We find decent agreement between mock and observed $η$ distribution shapes; however, the FMOS-COSMOS and MOSDEF mocks show a systematically low median and scatter in $η$ in comparison to the observations. This work also presents the novel approach of analytically deriving the relationship between the intrinsic scatter in $η$, scatter added by measurement uncertainties, and observed scatter, resulting in an intrinsic burstiness measurement of $0.06-0.16$ dex.
