Optical-faint, Far-infrared-bright Herschel Sources in the CANDELS Fields: Ultra-Luminous Infrared Galaxies at z>1 and the Effect of Source Blending
Haojing Yan, Mauro Stefanon, Zhiyuan Ma, Steven Willner, Rachel Somerville, Matthew Ashby, Romeel Dave, Pablo G. Perez-Gonzalez, Antonio Cava, Tommy Wiklind, Da… 展开作者
Haojing Yan, Mauro Stefanon, Zhiyuan Ma, Steven Willner, Rachel Somerville, Matthew Ashby, Romeel Dave, Pablo G. Perez-Gonzalez, Antonio Cava, Tommy Wiklind, Dale Kocevski, Marc Rafelski, Jeyhan Kartaltepe, Asantha Cooray
The Herschel very wide-field surveys have charted hundreds of square degrees in multiple far-IR (FIR) bands. While the Sloan Digital Sky Survey (SDSS) is currently the best resource for optical counterpart identifications over such wide areas, it does not detect a large number of Herschel FIR sources and leaves their nature undetermined. As a test case, we studied seven "SDSS-invisible", very bright 250um sources (S_{250} > 55 mJy) in the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) fields where we have a rich multi-wavelength data set. We took a new approach to decompose the FIR sources, using the near-IR or the optical images directly for position priors. This is an improvement over the previous decomposition efforts where the priors are from mid-IR data that still suffer from the source blending problem in the first place. We found that in most cases the single Herschel sources are made of multiple components that are not necessarily at the same redshifts. Our decomposition succeeded in identifying and extracting their major contributors. We show that these are all ULIRGs at z ~ 1--2 whose high L_IR is mainly due to dust-obscured star formation. Most of them would not be selected as sub-mm galaxies. They all have complicated morphologies indicative of merger or violent instability, and their stellar populations are heterogeneous in terms of stellar masses, ages and formation histories. Their current ULIRG phases are of various degrees of importance in their stellar mass assembly. Our practice provides a promising starting point to develop an automatic routine to reliably study bright Herschel sources.
3D-Herschel: Constraining Dust Emission with Panchromatic Modeling of 3D-HST Galaxies
University of Massachusetts, Amherst（马萨诸塞大学阿默斯特分校）；Niels Bohr Institute, University of Copenhagen（哥本哈根大学尼尔斯·玻尔研究所）；The Pennsylvania State University（宾夕法尼亚州立大学）；NSF’s National Optical-Infrared Astronomy Research Laboratory（美国国家光学-红外天文研究实验室）；Hiroshima University（广岛大学）
The CANDELS/SHARDS multi-wavelength catalog in GOODS-N: Photometry, Photometric Redshifts, Stellar Masses, Emission line fluxes and Star Formation Rates
Dust Heating by Low-mass Stars in Massive Galaxies at z<1
利用Hubble空间望远镜/Wide Field Camera 3的成像数据和多波长光度表，研究了CANDELS场中0.2<z<1.0处被动演化星系和恒星形成星系的尘埃温度。我们从这些星系的恒星质量和表面亮度分布估算了低质量恒星的恒星辐射场，并计算了它们的稳态尘埃温度。首先，我们使用赫歇尔室女星系团巡天的深远红外数据，使用附近的早型星系测试了我们的方法，并证实估计的尘埃温度与观测到的温度在不确定性范围内是一致的。然后我们将该方法应用于0.2<z<1.0的星系，发现大多数Mstar > 10^{10} Msun的被动演化星系都具有较高的尘埃温度（Tdust > 20 K），因此实验室实验预计在弥漫ISM中尘埃颗粒表面分子氢的形成效率很低。被动演化星系的比例强烈依赖于所有红移处的预期尘埃温度，并随着温度的增加而迅速增加。这些结果表明，大质量星系中低质量恒星对尘埃的加热对大质量星系被动演化的继续起着重要作用，因为缺乏氢分子对紫外辐射的屏蔽作用，阻止了气体冷却和新恒星的形成。
The FourStar Galaxy Evolution Survey (ZFOURGE): ultraviolet to far-infrared catalogs, medium-bandwidth photometric redshifts with improved accuracy, stellar masses, and confirmation of quiescent galaxies to z~3.5
The Spitzer/IRAC Legacy over the GOODS Fields: Full-Depth 3.6, 4.5, 5.8 and 8.0um Mosaics and Photometry for > 9000 Galaxies at z~3.5-10 from the GOODS Re-ionization Era wide-Area Treasury from Spitzer (GREATS)
