Dust Attenuation, Star Formation, and Metallicity in z ∼ 2–3 Galaxies from KBSS-MOSFIRE
Dust Attenuation, Star Formation, and Metallicity in z ∼ 2–3 Galaxies from KBSS-MOSFIRE
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来自 KBSS-MOSFIRE 的 z 〜 2–3 星系中的尘埃衰减、恒星形成和金属丰度
DOI：
10.3847/1538-4357/aaf386
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
N. Reddy
中科院分区：
文献类型：
--
作者：
Rachel L. Theios;C. Steidel;A. Strom;G. Rudie;R. Trainor;N. Reddy
本文对凯克重子结构巡天中的317个2.0 ≤ z ≤ 2.7恒星形成星系进行了详细的分析。利用Keck/LRIS和Keck/MOSFIRE的互补光谱观测，以及光谱能量分布（SED）适合宽带测光，我们研究了相同星系的联合静止紫外和静止光学特性，包括恒星和星云尘埃衰减，金属丰度和星星形成率（SFR）。推断的恒星人口（红化，年龄，SFR，和恒星质量）的参数是强烈依赖于假设的恒星人口模型的细节和衰减曲线的形状。星云红化一般比连续红化大，但散射大。与本地星系相比，高红移星系在固定的星云红化下具有较低的气相金属丰度（和/或较高的星云激发），在固定的恒星质量下具有较高的星云红化，这与气体分数随红移增加一致。我们发现连续红化与12 + log（O/H）O_3N_2的相关性为3.0σ显著性，而星云红化仅与1.1σ显著性相关。这可能反映了连续红化和O3 N2对大质量恒星产生的电离辐射场形状的依赖性。最后，我们表明，基于Hα和基于SED的估计SFR表现出显着的分散相对于彼此，平均同意只有特定的组合的频谱合成模型和衰减曲线。我们发现，SMC消光曲线预测一致的SFR，如果我们假设太阳下（0.14 Z）的二元星星模型，有利于高红移星系。
We present a detailed analysis of 317 2.0 ≤ z ≤ 2.7 star-forming galaxies from the Keck Baryonic Structure Survey. Using complementary spectroscopic observations with Keck/LRIS and Keck/MOSFIRE, as well as spectral energy distribution (SED) fits to broadband photometry, we examine the joint rest-UV and rest-optical properties of the same galaxies, including stellar and nebular dust attenuation, metallicity, and star formation rate (SFR). The inferred parameters of the stellar population (reddening, age, SFR, and stellar mass) are strongly dependent on the details of the assumed stellar population model and the shape of the attenuation curve. Nebular reddening is generally larger than continuum reddening, but with large scatter. Compared to local galaxies, high-redshift galaxies have lower gas-phase metallicities (and/or higher nebular excitation) at fixed nebular reddening, and higher nebular reddening at fixed stellar mass, consistent with gas fractions that increase with redshift. We find that continuum reddening is correlated with 12 + log(O/H)O3N2 at 3.0σ significance, whereas nebular reddening is correlated with only 1.1σ significance. This may reflect the dependence of both continuum reddening and O3N2 on the shape of the ionizing radiation field produced by the massive stars. Finally, we show that Hα-based and SED-based estimates of SFR exhibit significant scatter relative to one another, and on average agree only for particular combinations of spectral synthesis models and attenuation curves. We find that the SMC extinction curve predicts consistent SFRs if we assume the subsolar (0.14 Z⊙) binary star models that are favored for high-redshift galaxies.
影响因子：
56.9
作者：
H. Sana;S. D. Mink;A. D. Koter;N. Langer;C. Evans;M. Gieles;E. Gosset;R. Izzard;J. L. Bouquin-J.
通讯作者：
H. Sana;S. D. Mink;A. D. Koter;N. Langer;C. Evans;M. Gieles;E. Gosset;R. Izzard;J. L. Bouquin-J.