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Three Lyman-α-emitting filaments converging to a massive galaxy group at z = 2.91: discussing the case for cold gas infall

Daddi, E. and Valentino, F. and Rich, R. M. and Neill, J. D. and Gronke, M. and O’Sullivan, D. and Elbaz, D. and Bournaud, F. and Finoguenov, A. and Marchal, A. and Delvecchio, I. and Jin, S. and Liu, D. and Strazzullo, V. and Calabrò, A. and Coogan, R. and D’Eugenio, C. and Gobat, R. and Kalita, B. S. and Laursen, P. and Martin, D. C. and Puglisi, A. and Schinnerer, E. and Wang, T. (2021) Three Lyman-α-emitting filaments converging to a massive galaxy group at z = 2.91: discussing the case for cold gas infall. Astronomy and Astrophysics, 649 . Art. No. A78. ISSN 0004-6361. doi:10.1051/0004-6361/202038700.

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We have discovered a 300 kpc-wide giant Lyman-α (Lyα) nebula centered on the massive galaxy group RO-1001 at z = 2.91 in the Cosmic Evolution Survey field. Keck Cosmic Web Imager observations reveal three cold gas filaments converging into the center of the potential well of its ∼4 × 10¹³ M_⊙ dark matter halo, hosting 1200 M_⊙ yr⁻¹ of star formation as probed by Atacama Large Millimeter Array and NOrthern Extended Millimeter Array observations. The nebula morphological and kinematics properties and the prevalence of blueshifted components in the Lyα spectra are consistent with a scenario of gas accretion. The upper limits on active galactic nuclei activity and overall energetics favor gravity as the primary Lyα powering source and infall as the main source of gas flows to the system. Although interpretational difficulties remain, with outflows and likely also photoionization with ensuing recombination still playing a role, this finding provides arguably an ideal environment to quantitatively test models of cold gas accretion and galaxy feeding inside an actively star-forming massive halo at high redshift.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Daddi, E.0000-0002-3331-9590
Valentino, F.0000-0001-6477-4011
Rich, R. M.0000-0003-0427-8387
Neill, J. D.0000-0002-0466-1119
Gronke, M.0000-0003-2491-060X
Elbaz, D.0000-0002-7631-647X
Bournaud, F.0000-0002-5743-0250
Finoguenov, A.0000-0002-4606-5403
Delvecchio, I.0000-0001-8706-2252
Calabrò, A.0000-0003-2536-1614
Martin, D. C.0000-0002-8650-1644
Puglisi, A.0000-0001-9369-1805
Schinnerer, E.0000-0002-3933-7677
Alternate Title:Three Lyman-alpha emitting filaments converging to a massive galaxy group at z = 2.91: discussing the case for cold gas infall, Three Lyman-alpha emitting filaments converging to a massive galaxy group at z = 2.91: a case for cold gas infall
Additional Information:© E. Daddi et al. 2021. Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Received 19 June 2020; Accepted 22 February 2021; Published online 13 May 2021. We are indebted to Sebastiano Cantalupo for use of his CubeEx software and for enlightening discussions. We also thank Matt Lehnert, Avishai Dekel, Nir Mandelker, Anne Verhamme, and Mauro Giavalisco for discussions. This work includes observations carried out with the IRAM NOEMA Interferometer. F.V. acknowledges support from the Carlsberg Foundation Research Grant CF18-0388 “Galaxies: Rise And Death” and the Cosmic Dawn Center of Excellence funded by the Danish National Research Foundation under then Grant No. 140. RMR acknowledges financial support from HST-GO-15910. MG was supported by NASA through the NASA Hubble Fellowship grant HST-HF2-51409 and acknowledges support from HST grants HST-GO-15643.017-A, HST-AR-15039.003-A, and XSEDE grant TG-AST180036. AP acknowledges financial support from STFC through grants ST/T000244/1 and ST/P000541/1. S.J. acknowledges financial support from the Spanish Ministry of Science, Innovation and Universities (MICIU) under AYA2017-84061-P, co-financed by FEDER (European Regional Development Funds). VS acknowledges support from the ERC-StG ClustersXCosmo grant agreement 716762. IRAM is supported by INSU/CNRS (France), MPG (Germany) and IGN (Spain). This paper makes use of data from ALMA: a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada), MOST and ASIAA (Taiwan), and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO and NAOJ. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. This work was supported by the Programme National Cosmology et Galaxies (PNCG) of CNRS/INSU with INP and IN2P3, co-funded by CEA and CNES.
Funding AgencyGrant Number
Carlsberg FoundationCF18-0388
Danish National Research Foundation140
NASA Hubble FellowshipHST-GO-15910
NASA Hubble FellowshipHST-HF2-51409
NASA Hubble FellowshipHST-GO-15643.017-A
NASA Hubble FellowshipHST-AR-15039.003-A
Science and Technology Facilities Council (STFC)ST/T000244/1
Science and Technology Facilities Council (STFC)ST/P000541/1
Ministerio de Ciencia, Innovación y Universidades (MICIU)AYA2017-84061-P
Fondo Europeo de Desarrollo Regional (FEDER)UNSPECIFIED
European Regional Development Funds (ERDF)UNSPECIFIED
European Research Council (ERC)716762
Institut national des sciences de l'Univers (INSU)UNSPECIFIED
Centre National de la Recherche Scientifique (CNRS)UNSPECIFIED
Instituto Geográfico Nacional (IGN)UNSPECIFIED
Programme National Cosmology et Galaxies (PNCG)UNSPECIFIED
Institut National de Physique Nucléaire et de Physique des Particules (IN2P3)UNSPECIFIED
Commissariat à l’Energie Atomique (CEA)UNSPECIFIED
Subject Keywords:galaxies: evolution – Galaxy: formation – galaxies: groups: individual: RO-1001 – large-scale structure of Universe – galaxies: clusters: intracluster medium
Record Number:CaltechAUTHORS:20210518-071644588
Persistent URL:
Official Citation:Three Lyman-α-emitting filaments converging to a massive galaxy group at z = 2.91: discussing the case for cold gas infall. E. Daddi, F. Valentino, R. M. Rich, J. D. Neill, M. Gronke, D. O’Sullivan, D. Elbaz, F. Bournaud, A. Finoguenov, A. Marchal, I. Delvecchio, S. Jin, D. Liu, V. Strazzullo, A. Calabro, R. Coogan, C. D’Eugenio, R. Gobat, B. S. Kalita, P. Laursen, D. C. Martin, A. Puglisi, E. Schinnerer and T. Wang. A&A, 649 (2021) A78; DOI:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:109159
Deposited By: Tony Diaz
Deposited On:19 May 2021 19:35
Last Modified:19 May 2021 19:35

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