MAGPI巡天：发射线产品数据发布及光谱孔径覆盖分数对巴尔末减缩-恒星质量关系的影响
The MAGPI Survey: Emission Line Products Data Release and the Role of Spectroscopic Aperture Covering Fraction on the Balmer Decrement-Stellar Mass Relation
中文总结 AI 辅助
本研究发布MAGPI巡天的发射线产品数据，发现光谱孔径覆盖分数f_c显著影响巴尔末减缩-恒星质量关系，该关系呈红移演化趋势，与紫外恒星连续谱消光的红移演化行为一致。
中文摘要 AI 辅助
中世纪星系积分场光谱巡天（MAGPI）是欧洲南方天文台甚大望远镜（ESO VLT）使用MUSE仪器开展的大型项目。本文发布了MAGPI的发射线产品数据，基于GIST软件，覆盖MAGPI全部56个天区，包含836个红移0.05≤z_spec≤0.424（Hα窗口）星系的发射线图，以及2607个红移0.05≤z_spec≤1.50（上限为[OⅡ]截止）星系的基于孔径的发射线测量值。我们利用这些数据研究尘埃消光，这是推导星系性质时的主要不确定来源，而这些性质对约束星系演化模型至关重要。我们探讨了光谱孔径覆盖分数（f_c）对巴尔末减缩（BD=F(Hα)/F(Hβ)，一种常用的尘埃消光代理）与总恒星质量（M_★）之间关系的影响。多项研究表明，BD-M_★关系可能与红移无关，但不同巡天因光纤或狭缝尺寸不同，往往具有不同的f_c，这会导致系统偏差。我们的结果显示，f_c对该关系有显著影响，原因是星系具有负的BD径向梯度，且在z≲0.4时，质量更大的星系的该梯度更负。将平均f_c≥0.5的光谱巡天进行比较，我们发现BD-M_★关系呈现出红移演化的趋势，且与紫外恒星连续谱消光的红移演化（A_FUV-z）行为大致一致，星系的平均尘埃消光在z~1.2时达到峰值，在更低和更高红移时均降低。
英文摘要
The Middle Ages Galaxy Properties with Integral field spectroscopy (MAGPI) survey is a Large Program on the European Southern Observatory Very Large Telescope using the MUSE instrument. This paper presents the data release for the MAGPI emission line products and includes emission line maps for 836 galaxies at $0.05\leq z_\mathrm{spec}\leq 0.424$ ($\mathrm{H}α$-window) and aperture-based emission line measurements for 2,607 galaxies at $0.05\leq z_\mathrm{spec}\leq 1.50$ (upper bound is [OII] cut-off), both based on the GIST software, for all 56 MAGPI fields. We use these data to examine dust attenuation, which represents a major source of uncertainty in the derived properties of galaxies that are critical to constrain models of galaxy evolution. We examine the role that the spectroscopic aperture covering fraction ($f_c$) has on the relationship between the Balmer decrement ($\mathrm{BD}=F(\mathrm{H}α)/F(\mathrm{H}β)$; a common proxy for dust attenuation) and the total stellar mass ($M_\star$). Several studies have suggested that the BD-$M_\star$ relation may be redshift invariant; however, the compared surveys often have different $f_c$ due to their differing fibre or slit sizes that can cause systematic offsets. Our results indicate that $f_c$ has a significant impact on this relationship, due to galaxies having negative BD radial gradients, which are more negative for more massive galaxies at $z\lesssim0.4$. Comparing spectroscopic surveys with $\left<f_c\right> \gtrsim 0.5$, we find that the BD-$M_\star$ relation shows a preference for redshift evolution and is roughly consistent with the behaviour of UV stellar continuum attenuation redshift evolution ($A_\mathrm{FUV}$-$z$), with the average dust attenuation in galaxies peaking at $z\sim1.2$ and decreasing at lower and higher redshifts.
