The Intense Starburst HDF850.1 in a Galaxy Overdensity at z=5.2 in the Hubble Deep Field
Fabian Walter, R. Decarli, C. Carilli, F. Bertoldi, P. Cox, E. Da Cunha, E. Daddi, M. Dickinson, D. Downes, D. Elbaz, R. Ellis, J. Hodge, R. Neri, D. Riechers, … 展开作者
Fabian Walter, R. Decarli, C. Carilli, F. Bertoldi, P. Cox, E. Da Cunha, E. Daddi, M. Dickinson, D. Downes, D. Elbaz, R. Ellis, J. Hodge, R. Neri, D. Riechers, A. Weiss, E. Bell, H. Dannerbauer, M. Krips, M. Krumholz, L. Lentati, R. Maiolino, K. Menten, H. -W. Rix, B. Robertson, H. Spinrad, D. Stark, D. Stern
The Hubble Deep Field (HDF) is a region in the sky that provides one of the deepest multi-wavelength views of the distant universe and has led to the detection of thousands of galaxies seen throughout cosmic time. An early map of the HDF at a wavelength of 850 microns that is sensitive to dust emission powered by star formation revealed the brightest source in the field, dubbed HDF850.1. For more than a decade, this source remained elusive and, despite significant efforts, no counterpart at shorter wavelengths, and thus no redshift, size or mass, could be identified. Here we report, using a millimeter wave molecular line scan, an unambiguous redshift determination for HDF850.1 of z=5.183. This places HDF850.1 in a galaxy overdensity at z~5.2 in the HDF, corresponding to a cosmic age of only 1.1 Gyr after the Big Bang. This redshift is significantly higher than earlier estimates and higher than most of the >100 sub-millimeter bright galaxies identified to date. The source has a star formation rate of 850 M_sun/yr and is spatially resolved on scales of 5 kpc, with an implied dynamical mass of ~1.3x10^11 M_sun, a significant fraction of which is present in the form of molecular gas. Despite our accurate redshift and position, a counterpart arising from starlight remains elusive.
We report the serendipitous discovery of a dusty, starbursting galaxy at $z=5.667$ (hereafter called CRLE) in close physical association with the "normal" main-sequence galaxy HZ10 at $z=5.654$. CRLE was identified by detection of [CII], [NII] and CO(2-1) line emission, making it the highest redshift, most luminous starburst in the COSMOS field. This massive, dusty galaxy appears to be forming stars at a rate of at least 1500$\,M_\odot$ yr$^{-1}$ in a compact region only $\sim3$ kpc in diameter. The dynamical and dust emission properties of CRLE suggest an ongoing merger driving the starburst,…
We report interferometric measurements of [NII] 205 um fine-structure line emission from a representative sample of three galaxies at z=5-6 using the Atacama Large (sub)Millimeter Array (ALMA). These galaxies were previously detected in [CII] and far-infrared continuum emission and span almost two orders of magnitude in star formation rate (SFR). Our results show at least two different regimes of ionized inter-stellar medium properties for galaxies in the first billion years of cosmic time, separated by their L_[CII]/L_[NII] ratio. We find extremely low [NII] emission compared to [CII] (L_ [CI…
We report the results of a deep SCUBA-2 850- and 450-$μ$m survey for dust-obscured ultra-luminous infrared galaxies (U/LIRGs) in the field of the z=1.46 cluster XCS J2215.9-1738. We detect a striking overdensity of sub-millimeter sources coincident with the core of this cluster: $\sim 3-4 \times$ higher than expected in a blank field. We use the likely radio and mid-infrared counterparts to show that the bulk of these sub-millimeter sources have spectroscopic or photometric redshifts which place them in the cluster and that their multi-wavelength properties are consistent with this association…
Imaging Atomic and Highly Excited Molecular Gas in a z=6.42 Quasar Host Galaxy: Copious Fuel for an Eddington-Limited Starburst at the End of Cosmic Reionization
The Cosmic Owl: Twin Active Collisional Ring Galaxies with Starburst Merging Front at $z=1.14$
Tsinghua University(清华大学);National Radio Astronomy Observatory(国家射电天文台);The University of Tokyo(东京大学);Kavli Institute for the Physics and Mathematics of the Universe (WPI)(宇宙物理与数学研究 Kavli 研究所(WPI));Center for Data-Driven Discovery, Kavli IPMU (WPI), UTIAS(数据驱动发现中心,Kavli IPMU(WPI),UTIAS);Aix Marseille Univ.(艾克斯马赛大学);CNRS(法国国家科学研究中心);CNES(法国国家空间研究中心);LAM(拉格朗日天体物理学实验室);European Southern Observatory(欧洲南方天文台)
Do Submillimeter Galaxies Trace Megaparsec Large-scale Structures? -- An Overdensity Analysis of 449 Submillimeter Galaxies in COSMOS
Purple Mountain Observatory, Chinese Academy of Science(中国科学院紫金山天文台);School of Astronomy and Space Sciences, University of Science and Technology of China(中国科学技术大学天文与空间科学学院);State Key Laboratory of Radio Astronomy and Technology, Purple Mountain Observatory, Chinese Academy of Sciences(中国科学院紫金山天文台射电天文与技术重点实验室);Instituto de Astrofísica de Canarias (IAC)(加那利天体物理研究所);Universidad de La Laguna(拉古纳大学);INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna(意大利国家天体物理研究所博洛尼亚空间科学观测站);INAF-Osservatorio Astronomico di Capodimonte(意大利国家天体物理研究所卡波迪蒙特天文台);Dipartimento di Fisica e Astronomia “A. Righi”, Alma Mater Studiorum Università di Bologna(博洛尼亚大学阿玛·玛特·斯图迪奥鲁姆物理与天文学“A. Righi”系)
We study a large galaxy sample from the Spitzer Matching Survey of the UltraVISTA ultra-deep Stripes (SMUVS) to search for sources with enhanced 3.6 micron fluxes indicative of strong Halpha emission at z=3.9-4.9. We find that the percentage of "Halpha excess" sources reaches 37-40% for galaxies with stellar masses log10(M*/Msun) ~ 9-10, and decreases to <20% at log10(M*/Msun) ~ 10.7. At higher stellar masses, however, the trend reverses, although this is likely due to AGN contamination. We derive star formation rates (SFR) and specific SFR (sSFR) from the inferred Halpha equivalent widths (EW…
远红外和亚毫米波长的巡天已经确定了尘埃恒星形成星系(DSFG)在宇宙中恒星质量聚集和大质量星系演化中的重要作用。这些星系中最明亮的红外线光度超过10 $^{13}$ L $_{\odot}$,意味着恒星的形成速率为每年数千个太阳质量。它们代表了宇宙中最强烈的恒星爆发,但许多都是完全光学模糊的。它们在亚毫米波段很容易被探测到,这是由于尘埃被新形成的恒星的紫外线辐射加热。总的来说,宇宙中所有尘埃、恒星形成的星系都产生一个红外辐射场,其能量密度与所有可见星系在紫外和可见光波长下的直接星光辐射相等。这种河外红外背景光的大部分来自不同的星系,从富含气体的星系盘到合并的强烈恒星爆发星系。近年来,远红外仪器的重大进展,无论是基于空间还是基于地面,都导致了近100万个DSFG的检测,但我们对管理尘埃星暴阶段开始和结束的基础天体物理学的理解仍处于初期阶段。这篇综述旨在总结DSFG研究的现状,特别关注最好理解的子集(亚毫米星系,十多年前对这一领域的最后一次综述中总结的亚毫米星系)的详细表征,Blain等人,2002),而且最近发现的DSFG种群的选择和表征。我们回顾DSFG人口统计,他们的物理性质,包括尘埃,气体和恒星的内容,他们的环境,以及目前的理论模型与这些星系的形成和演化。
Ionization Parameter as a Diagnostic of Radiation and Wind Pressures in H II Regions and Starburst Galaxies
电离参数U对于测量来自大质量星团的辐射压力反馈是潜在有用的,因为它反映了辐射与气体压力的比率,并且很容易从中红外线比率导出。我们考虑几种影响,确定在HII地区和星系的U的表观值。上限由辐射压力对气体的压缩设定。对于给定的辐射强度,来自恒星风的压力和中性团块的存在都会降低U。辐射最强烈的区域被电离光子的内部尘埃吸收而选择性地变暗,导致星系尺度上的观测偏差。我们探索这些影响的分析和数值,并用它们来解释以前的观测结果。我们发现,辐射约束设置的上限log_10 U = -1在个别地区看到。未分辨的星爆显示的最大值约为-2.3。虽然较低,但这也与其HII区域的大部分以辐射为主相一致,考虑到用于解释未解决区域的不同技术,并考虑到尘埃吸收造成的偏差。我们推断,许多个别的,强烈的照明区域不能由恒星风占主导地位,即使在银河系尺度上平均,冲击风压不可能比辐射压力大。因此,绝大多数HII区不可能是绝热风泡。我们的模型意味着金属丰度的物理结构和尘埃衰减的辐射为主的地区,这两者都应该有很大的变化,在一个临界金属丰度约二十分之一的太阳。
We present a detailed census of galaxies in and around PC217.96+32.3, a spectroscopically confirmed Coma analog at z=3.78. Diverse galaxy types identified in the field include Lya emitters (LAEs), massive star-forming galaxies, and ultra-massive galaxies (log (Mstar/Msun)>= 11) which may have already halted their star formation. The sky distribution of the star-forming galaxies suggests the presence of a significant overdensity (delta_g=8+/-2), which is spatially offset from the previously confirmed members by 3-4 Mpc to the west. Candidate quiescent and post-starburst galaxies are also found …