The Evolution of Gas-Phase Metallicity and Resolved Abundances in Star-forming Galaxies at z ≈ 0.6 – 1.8
The Evolution of Gas-Phase Metallicity and Resolved Abundances in Star-forming Galaxies at z ≈ 0.6 – 1.8
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z ≈ 0.6 – 1.8 处恒星形成星系中气相金属丰度的演化和解析丰度
DOI：
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发表时间：
2020
影响因子：
4.8
通讯作者：
Lancaster
中科院分区：
文献类型：
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作者：
S. Gillman;A. Tiley;A. M. Swinbank;U. Dudzevivciut.e;R. Sharples;I. Smail;C. Harrison;A. Bunker;M. Bureau;M. Cirasuolo;G. Magdis;T. Mendel;J. P. S. Cea;Durham;Dawn;Copenhagen;Dtu;Icrar;Perth;CfAI;Newcastle;Uk;Oxford;Ipmu;Japan;Eso;Munich;Denmark;Iaasars;Greece.;Anu;Australia.;Lancaster
我们分析了10650个恒星形成星系在z = 0.6 - 1.8的化学丰度特性。利用K波段多目标光谱仪（KMOS）的积分场观测，我们量化了[N ii]/Hα发射线比，这是星际介质中气相氧丰度的代表。定义了z = 0.6 - 1.0和z = 1.2 - 1.8的恒星质量-金属丰度关系，并分析了该关系中的散射与星系基本性质（Hα恒星形成率、Hα比恒星形成率、自转优势、恒星连续半光半径和哈勃型形态）之间的相关性。我们发现，对于一个给定的恒星质量，更高的恒星形成，更大的和不规则的星系有较低的气相金属丰度，这可能是由于它们的表面质量密度较低，不规则系统的气体分数较高。我们测量了星系中气相金属丰度的径向依赖性，建立了一个中值，光束拖尾校正，金属丰度梯度ΔZ/ΔR= 0.002 ± 0.004 dex kpc−1，表明平均而言，对半径没有显着的依赖性。一个星系的金属丰度梯度是独立于其静止框架的光学形态，而与它的恒星质量和特定的恒星形成率，在协议的星系演化的由内而外的模型，以及它的旋转优势。我们量化了金属丰度梯度的演变，将我们样本中的ΔZ/ΔR分布与数值模拟和z = 0 - 3的观测结果进行了比较。我们样本中的星系比本地恒星形成星系表现出更平坦的金属丰度梯度，这与恒星反馈在重新分配金属中发挥关键作用的数值模型一致。
We present an analysis of the chemical abundance properties of ≈650 star-forming galaxies at z ≈ 0.6 – 1.8. Using integral-field observations from the K - band Multi-Object Spectrograph (KMOS), we quantify the [N ii]/Hα emission-line ratio, a proxy for the gas-phase Oxygen abundance within the interstellar medium. We define the stellar mass – metallicity relation at z ≈ 0.6 – 1.0 and z ≈ 1.2 – 1.8 and analyse the correlation between the scatter in the relation and fundamental galaxy properties (e.g. Hα star-formation rate, Hα specific star-formation rate, rotation dominance, stellar continuum half-light radius and Hubble-type morphology). We find that for a given stellar mass, more highly star-forming, larger and irregular galaxies have lower gas-phase metallicities, which may be attributable to their lower surface mass densities and the higher gas fractions of irregular systems. We measure the radial dependence of gas-phase metallicity in the galaxies, establishing a median, beam smearing-corrected, metallicity gradient of ΔZ/ΔR= 0.002 ± 0.004 dex kpc−1, indicating on average there is no significant dependence on radius. The metallicity gradient of a galaxy is independent of its rest-frame optical morphology, whilst correlating with its stellar mass and specific star-formation rate, in agreement with an inside-out model of galaxy evolution, as well as its rotation dominance. We quantify the evolution of metallicity gradients, comparing the distribution of ΔZ/ΔR in our sample with numerical simulations and observations at z ≈ 0 – 3. Galaxies in our sample exhibit flatter metallicity gradients than local star-forming galaxies, in agreement with numerical models in which stellar feedback plays a crucial role redistributing metals.
DOI：
10.1093/mnras/stab1803
发表时间：
2020-07
期刊：
arXiv: Astrophysics of Galaxies
影响因子：
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作者：
Z. Hemler;P. Torrey;J. Qi;L. Hernquist;M. Vogelsberger;Xiangcheng Ma;L. Kewley;D. Nelson;A. Pillepich;R. Pakmor;F. Marinacci
通讯作者：
Z. Hemler;P. Torrey;J. Qi;L. Hernquist;M. Vogelsberger;Xiangcheng Ma;L. Kewley;D. Nelson;A. Pillepich;R. Pakmor;F. Marinacci