title: Molecular gas in the halo fuels the growth of a massive cluster galaxy at high redshift.
abstract: The largest galaxies in the universe reside in galaxy clusters. Using sensitive observations of carbon monoxide, we show that the Spiderweb galaxy-a massive galaxy in a distant protocluster-is forming from a large reservoir of molecular gas. Most of this molecular gas lies between the protocluster galaxies and has low velocity dispersion, indicating that it is part of an enriched intergalactic medium. This may constitute the reservoir of gas that fuels the widespread star formation seen in earlier ultraviolet observations of the Spiderweb galaxy. Our results support the notion that giant galaxies in clusters formed from extended regions of recycled gas at high redshift.
authors.affiliation: Centro de Astrobiología (Consejo Superior de Investigaciones Científicas-Instituto Nacional de Técnica Aerospacial), Carretera de Torrejón a Ajalvir, km 4, 28850 Torrejón de Ardoz, Madrid, Spain. bjornemonts@gmail.com.
authors.forename: B H C
authors.initials: BH
authors.lastname: Emonts
authors.affiliation: Sorbonne Universités, Université Pierre et Marie Curie, Université Paris 6 et Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7095, Institut d'Astrophysique de Paris, 75014 Paris, France.
authors.forename: M D
authors.initials: MD
authors.lastname: Lehnert
authors.affiliation: Centro de Astrobiología (Consejo Superior de Investigaciones Científicas-Instituto Nacional de Técnica Aerospacial), Carretera de Torrejón a Ajalvir, km 4, 28850 Torrejón de Ardoz, Madrid, Spain.|Facultad de Ciencias, Unidad Asociada Consejo Superior de Investigaciones Científicas, Astro-Universidad Autónoma de Madrid, Campus de Cantoblanco, 28049 Madrid, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Villar-Martín
authors.affiliation: Commonwealth Scientific and Industrial Research Organisation, Astronomy and Space Science, Australia Telescope National Facility, Epping, NSW 1710, Australia.|Western Sydney University, Penrith South, NSW 1797, Australia.
authors.forename: R P
authors.initials: RP
authors.lastname: Norris
authors.affiliation: Commonwealth Scientific and Industrial Research Organisation, Astronomy and Space Science, Australia Telescope National Facility, Epping, NSW 1710, Australia.
authors.forename: R D
authors.initials: RD
authors.lastname: Ekers
authors.affiliation: National Radio Astronomy Observatory, Socorro, NM 87801, USA.
authors.forename: G A
authors.initials: GA
authors.lastname: van Moorsel
authors.affiliation: Instituto de Astrofísica de Canarias, E-38205 La Laguna, Tenerife, Spain.|Departamento Astrofísica, Universidad de La Laguna, E-38206 La Laguna, Tenerife, Spain.|Institut für Astrophysik, Universität Wien, 1180 Wien, Austria.
authors.forename: H
authors.initials: H
authors.lastname: Dannerbauer
authors.affiliation: Istituto Nazionale di Astrofisica, Osservatorio Astronomico di Roma, 00040 Monteporzio (RM), Italy.
authors.forename: L
authors.initials: L
authors.lastname: Pentericci
authors.affiliation: Leiden Observatory, University of Leiden, 2300 RA Leiden, Netherlands.
authors.forename: G K
authors.initials: GK
authors.lastname: Miley
authors.affiliation: Commonwealth Scientific and Industrial Research Organisation, Astronomy and Space Science, Australia Telescope National Facility, Epping, NSW 1710, Australia.
authors.forename: J R
authors.initials: JR
authors.lastname: Allison
authors.affiliation: Sydney Institute for Astronomy, School of Physics, University of Sydney, NSW 2006, Australia.
authors.forename: E M
authors.initials: EM
authors.lastname: Sadler
authors.affiliation: Sorbonne Universités, Université Pierre et Marie Curie, Université Paris 6 et Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7095, Institut d'Astrophysique de Paris, 75014 Paris, France.
authors.forename: P
authors.initials: P
authors.lastname: Guillard
authors.affiliation: National Radio Astronomy Observatory, Socorro, NM 87801, USA.|Cavendish Laboratory, Cambridge CB3 0HE, UK.
authors.forename: C L
authors.initials: CL
authors.lastname: Carilli
authors.affiliation: Joint Institute for Very Long Baseline Interferometry, European Research Infrastructure Consortium, 7990 AA Dwingeloo, Netherlands.|Jodrell Bank Observatory, University of Manchester, Macclesfield, Cheshire SK11 9DL, UK.
authors.forename: M Y
authors.initials: MY
authors.lastname: Mao
authors.affiliation: Leiden Observatory, University of Leiden, 2300 RA Leiden, Netherlands.
authors.forename: H J A
authors.initials: HJ
authors.lastname: Röttgering
authors.affiliation: European Southern Observatory, 85748 Garching, Germany.
authors.forename: C
authors.initials: C
authors.lastname: De Breuck
authors.affiliation: International Centre for Radio Astronomy Research, Curtin University, Perth, Australia.
authors.forename: N
authors.initials: N
authors.lastname: Seymour
authors.affiliation: Centre for Extragalactic Astronomy, Department of Physics, Durham University, Durham DH1 3LE, UK.
authors.forename: B
authors.initials: B
authors.lastname: Gullberg
authors.affiliation: Centro de Astrobiología (Consejo Superior de Investigaciones Científicas-Instituto Nacional de Técnica Aerospacial), Carretera de Torrejón a Ajalvir, km 4, 28850 Torrejón de Ardoz, Madrid, Spain.|Institut für Theoretische Astrophysik, Zentrum für Astronomie der Universität Heidelberg, 69120 Heidelberg, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Ceverino
authors.affiliation: National Radio Astronomy Observatory, Socorro, NM 87801, USA.
authors.forename: P
authors.initials: P
authors.lastname: Jagannathan
authors.affiliation: European Southern Observatory, 85748 Garching, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Vernet
authors.affiliation: Commonwealth Scientific and Industrial Research Organisation, Astronomy and Space Science, Australia Telescope National Facility, Epping, NSW 1710, Australia.
authors.forename: B T
authors.initials: BT
authors.lastname: Indermuehle