MIGHTEE/COSMOS-3D: The discovery of three spectroscopically confirmed radio-selected star-forming galaxies at z=4.9-5.6
University of Oxford(牛津大学);University College London(伦敦大学学院);University of the Western Cape(西开普大学);University of Geneva(日内瓦大学);University of Edinburgh(爱丁堡大学)
R. G. Varadaraj, A. Saxena, S. Fakiolas, I. H. Whittam, M. J. Jarvis, R. A. Meyer, C. L. Hale, K. Kakiichi, M. Li, J. B. Champagne, B. Jin, Z. J. Li, M. Shuntov
备注:
11 pages, 5 figures. Accepted for publication in MNRAS
射电观测提供了一种不依赖尘埃的恒星形成和活动星系核(AGN)活动的探测手段,但需要足够深的数据才能在高红移(z>4.5)时探测这两种过程的交叉光度。我们报道了三个高红移射电源(HzRSs),在1.3 GHz处检测到z=4.9-5.6,其射电光度覆盖L_{1.3 GHz}≈2-5×10^{24} W Hz^{-1}。这些源最初通过归档哈勃、JWST NIRCam+MIRI和地面光度数据的光谱能分布(SED)拟合被识别为高红移候选者,然后通过JWST COSMOS-3D的宽视场无狭缝光谱法利用Hα发射线进行光谱确认。通过SED拟合测量的恒星形成率(SFRs)、Hα流量和1.3 GHz光度覆盖约100-1800 M_⊙ yr^{-1},显示这些SFR探测器之间有广泛的共识。我们发现这三个源位于z=4-6的恒星形成主序列上或0.5-1.0个数量级以上,并且经历了最近的恒星形成爆发。这些源具有扩展的静止紫外/光学形态,没有主导点源成分的证据,表明AGN不太可能主导它们的静止紫外和光学发射。其中两个源具有复杂的、多成分的静止紫外/光学形态,表明它们的恒星爆发可能由合并活动触发。这些HzRSs为探测z>4.5由恒星形成驱动的射电发射打开了新的窗口,代表了一个开始追踪恒星形成、不依赖尘埃的早期宇宙的机会。
英文摘要:
Radio observations offer a dust-independent probe of star formation and active galactic nucleus (AGN) activity, but sufficiently deep data are required to access the crossover luminosity between these processes at high redshift ($z>4.5$). We present three spectroscopically confirmed high-redshift radio sources (HzRSs) detected at 1.3 GHz at $z=4.9$-$5.6$, with radio luminosities spanning $L_{\rm 1.3 \, GHz}\approx2$-$5\times10^{24} \, \rm W \, Hz^{-1}$. These sources were first identified as high-redshift candidates through spectral energy distribution (SED) fitting of archival Hubble, JWST NIRCam+MIRI, and ground-based photometry, and then spectroscopically confirmed via the $\rm H\,α$ emission line using wide-field slitless spectroscopy from JWST COSMOS-3D. The star formation rates (SFRs) measured from SED fitting, the $\rm H\,α$ flux, and the 1.3 GHz luminosity, span $\sim100$-$1800\, M_{\odot} \, \rm yr^{-1}$, demonstrating broad agreement between these SFR tracers. We find that these three sources lie either on or $0.5$-1.0 dex above the star-forming main sequence at $z=4$-6 and have undergone a recent burst of star formation. The sources have extended rest-UV/optical morphologies with no evidence for a dominant point source component, indicating that an AGN is unlikely to dominate their rest-UV and optical emission. Two of the sources have complex, multi-component rest-frame UV/optical morphologies, suggesting that their starbursts may be triggered by merging activity. These HzRSs open up a new window towards probing radio emission powered by star formation alone at $z> 4.5$, representing a remarkable opportunity to begin tracing star formation, independent of dust, in the early Universe.
Deblending the MIGHTEE-COSMOS survey with XID+: The resolved radio source counts to $S_{1.4}\approx 5μ$Jy
University of South Africa(南非大学);University of the Western Cape(西开普敦大学);University of Oxford(牛津大学);South African Radio Astronomy Observatory (SARAO)(南非射电天文观测台);University of Hertfordshire(赫特福德大学)
MIGHTEE-HI: Environmental effects of cosmic filaments on extragalactic HI detections in the COSMOS and XMM-LSS fields
University of Oxford(牛津大学);University of Cambridge(剑桥大学);University of the Western Cape(西开普敦大学);University of Bristol(布里斯托大学);Universiteit Gent(根特大学);University of Edinburgh(爱丁堡大学);Inter-University Institute for Data Intensive Astronomy, Department of Astronomy, University of Cape Town(开普敦大学天文学系数据密集型天文跨大学研究所);Centre for Astrophysics Research, School of Physics, Astronomy and Mathematics, University(大学物理、天文与数学学院天体物理学研究中心)
Measurements of the HI intensity mapping power spectrum at low redshifts with MIGHTEE data: comparison with detected HI galaxies
University of the Western Cape(西开普敦大学);South African Radio Astronomy Observatory (SARAO)(南非射电天文观测台);The University of Edinburgh(爱丁堡大学);The University of Manchester(曼彻斯特大学)
MIGHTEE: The evolving radio luminosity functions of star-forming galaxies to $z\sim 4.5$ and the cosmic history of star formation
University of Oxford(牛津大学);UKRI STFC Rutherford Appleton Laboratory(英国研究与创新部STFC拉瑟福德阿普尔顿实验室);University of the Western Cape(西开普大学);Institute for Astronomy, University of Edinburgh(爱丁堡大学天文研究所);Carnegie Observatories(卡内基观测站);Rhodes University(罗德兹大学)
A MIGHTEE robust measurement of the star formation rate-radio correlation
University of Oxford(牛津大学);University of the Western Cape(西开普敦大学);Max Planck Institute for Extraterrestrial Physics(马克斯·普朗克地外物理学研究所);Excellence Cluster Universe(宇宙卓越集群);University of Edinburgh(爱丁堡大学)
MIGHTEE-HI: The direct detection of neutral hydrogen in galaxies at $z>0.25$
University of Oxford(牛津大学);University of the Western Cape(西开普敦大学);Rhodes University(罗兹大学);South African Radio Astronomy Observatory(南非射电天文观测台);University of Hertfordshire(赫特福德大学);Universiteit Gent(根特大学);University of Bristol(布里斯托大学);Queen’s University(女王大学)
Validating z > 7.5 Lyman Break Galaxy candidates in the COSMOS field with JWST/PASSAGE
Minnesota Institute for Astrophysics, University of Minnesota(明尼苏达大学天体物理研究所);INAF, Osservatorio Astronomico di Padova(意大利国家天体物理研究所帕多瓦天文台);International Centre for Radio Astronomy Research, University of Western Australia(西澳大利亚大学国际射电天文研究中心);Research School of Astronomy and Astrophysics, Australian National University(澳大利亚国立大学天文学与天体物理学研究学院);Space Telescope Science Institute(太空望远镜科学研究所);Stockholm University, Department of Astronomy(斯德哥尔摩大学天文学系);University of California, Los Angeles, Department of Physics and Astronomy(加州大学洛杉矶分校物理与天文学系);IPAC, California Institute of Technology(加州理工学院IPAC)
RUBIES spectroscopically confirms the high number density of quiescent galaxies from $\mathbf{2<z<5}$
University of Pittsburgh(匹兹堡大学);Max-Planck-Institut für Astronomie(马克斯·普朗克天文学研究所);Princeton University(普林斯顿大学);Space Telescope Science Institute(太空望远镜科学研究所);International Centre for Radio Astronomy Research (ICRAR)(国际射电天文研究中心);University of Western Australia(西澳大利亚大学);University of Massachusetts, Amherst(马萨诸塞大学阿默斯特分校);University of Wisconsin-Madison(威斯康星大学麦迪逊分校);The Pennsylvania State University(宾夕法尼亚州立大学)
Early Emergence of Environmental Effects: Accelerated Galaxy Assembly in a z=2.96 Protocluster in the COSMOS Field
Tsinghua University(清华大学);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所( Kavli IPMU ))
Tracing AGN-Galaxy Co-Evolution with UV Line-Selected Obscured AGN
University of Cape Town(开普敦大学);Inter-University Institute for Data Intensive Astronomy, Department of Astronomy, University of Cape Town(开普敦大学天文学系跨大学数据密集型天体物理研究所);INAF - Istituto di Radioastronomia(意大利国家天体物理研究所射电天文台);Inter-University Institute for Data Intensive Astronomy, Department of Physics and Astronomy, University of the Western Cape(西开普大学物理与天文学系跨大学数据密集型天体物理研究所);Dipartimento di Fisica e Astronomia “Augusto Righi”, Università degli Studi di Bologna(博洛尼亚大学“奥古斯托·里吉”物理与天文学系);INAF-OAS, 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天体物理学与空间科学观测站);Instituto de Astrofísíca e Ciências do Espaço, Faculdade de Ciências, Universidade de Lisboa(里斯本大学理学院空间科学与天体物理研究所);Astronomy and Astrophysics division, Physical Research Laboratory(物理研究实验室天文与天体物理部);Astrophysics, Department of Physics, University of Oxford(牛津大学物理系天体物理学组);Institute for Astronomy, University of Edinburgh(爱丁堡大学天体物理研究所);Department of Physics and Electronics, Rhodes University(罗德岛大学物理与电子学系);South African Radio Astronomy Observatory(南非射电天文观测台);Department of Physics and Astronomy, University of the Western Cape(西开普大学物理与天文学系)
COSMOS2025: The COSMOS-Web galaxy catalog of photometry, morphology, redshifts, and physical parameters from JWST, HST, and ground-based imaging
Cosmic Dawn Center (DAWN)(宇宙黎明中心);Niels Bohr Institute, University of Copenhagen(哥本哈根大学尼尔斯·玻尔研究所);University of Geneva(日内瓦大学);The University of Texas at Austin(德克萨斯大学奥斯汀分校);Institut d’Astrophysique de Paris, UMR 7095, CNRS, and Sorbonne Université(巴黎天体物理学研究所,法国国家科学研究中心联合研究单位7095,索邦大学);Department of Physics, University of California, Santa Barbara(加州大学圣塔芭芭拉分校物理系);Aix Marseille Univ, CNRS, LAM, Laboratoire d’Astrophysique de Marseille(艾克斯-马赛大学,法国国家科学研究中心,地中海天体物理学实验室);Université Paris-Saclay, Université Paris Cité, CEA, CNRS, AIM(巴黎萨克雷大学,巴黎西岱大学,法国原子能和替代能源委员会,法国国家科学研究中心,天体物理信息与模型实验室)
First Spectroscopic Confirmations of z ~ 7.0 Lya Emitting Galaxies in the LAGER Survey
窄带成像是发现大量z~6.6的高红移Lya发射星系(LAEs)的一种非常成功的方法。然而,在z> 7时,只有3个窄带选择性LAEs(2个在z~6.9-7.0,1个在z~7.3)得到了光谱证实,这阻碍了对这一关键时期宇宙再电离和星系演化的广泛研究。利用大面积窄带巡天LAGER(Lyman-Alpha Galerkin at the End of Reionization),我们在COSMOS场中选取了23个z~6.9的候选LAEs。在这项工作中,我们提出了12个候选人使用IMACS麦哲伦光谱的后续观测。对于其中的9个,观测足够深,可以检测到预期的线。在六个光源中识别出Lya发射线(成功率为2/3),包括3个发光的LAE,Lya光度为L(Lya)~ 10^{43.5} erg/s,是已知光谱证实的星系中最高的,>~7.0。这使光谱学确认的z>~7处的窄带选择LAE的样本大小增加了两倍,并确认了我们先前基于光度测量样本导出的Lya光度函数中的亮端凸起,支持斑片状再电离场景。两个发光的LAE出现物理联系,投影距离为1.1 pMpc,速度差为~ 170 km/s。它们可能位于由它们自己或与近邻产生的共同电离气泡中,这减少了Lya的IGM衰减。在一个源中可以看到一条暂时狭窄的NV $λ$ 1240线,暗示着中心大质量黑洞的活动,富含金属的线发射气体。