UVI colour gradients of 0.4
UVI colour gradients of 0.4
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CANDELS 中 0.4 z 1.4 恒星形成主序星系的 UVI 颜色梯度：尘埃消光和恒星形成剖面
DOI：
10.1093/mnras/stx1148
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发表时间：
2017
影响因子：
4.8
通讯作者：
Ashby M L N
中科院分区：
文献类型：
--
作者：
Wang Weichen;Faber S M;Liu F S;Guo Yicheng;Pacifici Camilla;Koo David C;Kassin Susan A;Mao Shude;Fang Jerome J;Chen Zhu;Koekemoer Anton M;Kocevski Dale D;Ashby M L N
本文利用径向颜色轮廓来推断z= 0.4-1.4恒星形成主序星系中尘埃、气体和恒星形成的分布。我们从基于standardarduvj的方法开始估计尘埃消光和特定恒星形成率（sSFR）。通过替换ib，创建了一种适用于ACS+WFC3数据的新校准方法（即uvidiagram）。利用基于CANDELS（宇宙组合近红外深河外遗产调查）的多波长多孔径测光目录，1328个星系的uvicolesprofiles被堆积在恒星质量和红移箱中。所得到的颜色梯度，覆盖了0.2-2.0有效半径的径向范围，随着星系质量和全球av的增加而强烈增加。颜色梯度方向几乎与Calzetti消光矢量平行，表明尘埃比恒星种群的变化起着更重要的作用。通过我们的校准，在测量的径向范围内，avs曲线比恒星质量曲线下降得慢得多。sSFR梯度几乎是平坦的，没有中心淬火特征，除了forM -百科> 1010.5M⊙，在那里观察到中心下降了20 - 25%。这两组剖面与之前的径向sSFR和（连续）avr测量结果吻合得很好。它们也与sSFR剖面一致，如果假设径向恒定的气尘比，则与最近流体动力学模型中的气体剖面一致。我们最后讨论了惊人的发现，星系内部的SFR与恒星质量密度有关，尽管那里的恒星质量表面密度很低，但外部的尘埃含量很高。
This paper uses radial colour profiles to infer the distributions of dust, gas and star formation inz= 0.4–1.4 star-forming main-sequence galaxies. We start with the standardUVJ-based method to estimate dust extinction and specific star formation rate (sSFR). By replacingJwithIband, a new calibration method suitable for use with ACS+WFC3 data is created (i.e.UVIdiagram). Using a multi-wavelength multi-aperture photometry catalogue based on CANDELS (Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey),UVIcolour profiles of 1328 galaxies are stacked in stellar mass and redshift bins. The resulting colour gradients, covering a radial range of 0.2–2.0 effective radii, increase strongly with galaxy mass and with globalAV. Colour gradient directions are nearly parallel to the Calzetti extinction vector, indicating that dust plays a more important role than stellar population variations. With our calibration, the resultingAVprofiles fall much more slowly than stellar mass profiles over the measured radial range. sSFR gradients are nearly flat without central quenching signatures, except forM⋆> 1010.5M⊙, where central declines of 20–25 per cent are observed. Both sets of profiles agree well with previous radial sSFR and (continuum)AVmeasurements. They are also consistent with the sSFR profiles and, if assuming a radially constant gas-to-dust ratio, gas profiles in recent hydrodynamic models. We finally discuss the striking findings that SFR scales with stellar mass density in the inner parts of galaxies, and that dust content is high in the outer parts despite low stellar mass surface densities there.