A comparison of observed and simulated absorption from H I, C IV, and Si IV around z ≈ 2 star-forming galaxies suggests redshift–space distortions are due to inflows
A comparison of observed and simulated absorption from H I, C IV, and Si IV around z ≈ 2 star-forming galaxies suggests redshift–space distortions are due to inflows
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对 z ≈ 2 恒星形成星系周围的 H I、C IV 和 Si IV 的观测到的和模拟的吸收进行比较表明，红移空间扭曲是由于流入造成的
DOI：
10.1093/mnras/stx1616
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发表时间：
2017
影响因子：
4.8
通讯作者：
T. Theuns
中科院分区：
文献类型：
--
作者：
M. Turner;J. Schaye;R. Crain;G. Rudie;C. Steidel;A. Strom;T. Theuns
我们研究的H I和金属线的吸收z 2恒星形成星系的凯克重子结构巡天模拟光谱的演化和组装的星系及其环境（EAGLE）的宇宙学，流体动力学模拟产生的数据进行比较分析。我们从模拟中提取视线，并比较H I，C IV，和Si IV周围的模拟和观察到的星系使用像素光学深度的吸收特性。我们模拟的分辨率，像素大小，和观测的信噪比，以及影响参数和星系红移误差的分布。我们发现EAGLE参考模型与观测结果非常吻合。特别是，模拟再现高金属线的光学深度发现在小银河系的距离，光学深度增强了2个适当的Mpc的影响参数，和突出的红移空间的扭曲，我们发现是由于特殊的速度，而不是红移误差。对于晕质量为10^（12.0）M的情况，这种一致性最好，观测到的恒星质量和模拟的恒星质量也最接近。我们研究了星系周围的中值离子质量加权径向气体速度，发现大部分气体都在下落，下落速度取决于晕而不是恒星质量。由此，我们得出结论，观察到的红移空间的扭曲主要是由流入，而不是流出。
We study H I and metal-line absorption around z ≈ 2 star-forming galaxies by comparing an analysis of data from the Keck Baryonic Structure Survey to mock spectra generated from the Evolution and Assembly of Galaxies and their Environments (EAGLE) cosmological, hydrodynamical simulations. We extract sightlines from the simulations and compare the properties of the absorption by H I, C IV, and Si IV around simulated and observed galaxies using pixel optical depths. We mimic the resolution, pixel size, and signal-to-noise ratio of the observations, as well as the distributions of impact parameters and galaxy redshift errors. We find that the EAGLE reference model is in excellent agreement with the observations. In particular, the simulation reproduces the high metal-line optical depths found at small galactocentric distances, the optical depth enhancements out to impact parameters of 2 proper Mpc, and the prominent redshift–space distortions which we find are due to peculiar velocities rather than redshift errors. The agreement is best for halo masses ∼10^(12.0) M⊙, for which the observed and simulated stellar masses also agree most closely. We examine the median ion mass-weighted radial gas velocities around the galaxies, and find that most of the gas is infalling, with the infall velocity depending on halo rather than stellar mass. From this, we conclude that the observed redshift–space distortions are predominantly caused by infall rather than outflows.
DOI：
10.1111/j.1365-2966.2009.15034.x
发表时间：
2008-08
影响因子：
4.8
作者：
K. Dolag;S. Borgani;S. Borgani;S. Borgani;G. Murante;V. Springel
通讯作者：
K. Dolag;S. Borgani;S. Borgani;S. Borgani;G. Murante;V. Springel