@article{533cdf111be8425b9eeb26a53c8d4224,
title = "The MeerKAT Fornax Survey: II. The rapid removal of HIfrom dwarf galaxies in the Fornax cluster",
abstract = "We present MeerKAT Fornax Survey atomic hydrogen (H′ ¯I) observations of the dwarf galaxies located in the central ~2.5×4 deg2 of the Fornax galaxy cluster (Rvir ~2). The H′ ¯I images presented in this work have a 3σ column density sensitivity between 2.7 and 50×1018 cm-2 over 25 km s-1 for spatial resolution between 4 and 1 kpc. We are able to detect an impressive MHI = 5×105 M⊙ 3σ point source with a line width of 50 km s-1 at a distance of 20 Mpc. We detected H′ ¯I in 17 out of the 304 dwarfs in our field, with 14 out of the 36 late-type dwarfs (LTDs) and three out of the 268 early-type dwarfs (ETDs). The H′ ¯I-detected LTDs have likely just joined the cluster and are on their first infall as they are located at large clustocentric radii, with comparable MHI and mean stellar surface brightness at fixed luminosity as blue, star-forming LTDs in the field. By contrast, the H′ ¯I-detected ETDs have likely been in the cluster longer than the LTDs and acquired their H′ ¯I through a recent merger or accretion from nearby H′ ¯I. Eight of the H′ ¯I-detected LTDs host irregular or asymmetric H′ ¯I emission and disturbed or lopsided stellar emission. There are two clear cases of ram pressure shaping the H′ ¯I, with the LTDs displaying compressed H′ ¯I on the side closest to the cluster centre and a one-sided, starless tail pointing away from the cluster centre. The H′ ¯I-detected dwarfs avoid the most massive potentials (i.e. cluster centre and massive galaxies), consistent with massive galaxies playing an active role in the removal of H′ ¯I. We created a simple toy model to quantify the timescale of H′ ¯I stripping in the cluster by reproducing the observed Mr′- MHI relation. We find that a MHI = 108 M⊙ dwarf is stripped in ~240 Myr. The model is consistent with our observations, where low-mass LTDs are directly stripped of their H′ ¯I from a single encounter and more massive LTDs can harbour a disturbed H′ ¯I morphology due to longer times or multiple encounters being required to fully strip their H′ ¯I. This is the first time dwarf galaxies with MHI ≲ 1×106 M⊙ have been detected and resolved beyond the local group and in a galaxy cluster.",
keywords = "Galaxies: clusters: individual: Fornax, Galaxies: dwarf, Galaxies: evolution, Galaxies: general, Galaxies: interactions, Radio lines: ISM",
author = "D. Kleiner and P. Serra and MacCagni, {F. M.} and Raj, {M. A.} and {De Blok}, {W. J.G.} and J{\'o}zsa, {G. I.G.} and P. Kamphuis and R. Kraan-Korteweg and F. Loi and A. Loni and Loubser, {S. I.} and Moln{\'a}r, {D. Cs} and Oosterloo, {T. A.} and R. Peletier and Pisano, {D. J.}",
note = "Funding Information: The MeerKAT telescope is operated by the South African Radio Astronomy Observatory, which is a facility of the National Research Foundation, an agency of the Department of Science and Innovation. We are grateful to the full MeerKAT team at SARAO for their work on building and commissioning MeerKAT. This work made use of the Inter-University Institute for Data Intensive Astronomy (IDIA) visualisation lab ( https://vislab.idia.ac.za ). IDIA is a partnership of the University of Cape Town, the University of Pretoria and the University of Western Cape. This work has received funding from the European Research Council (ERC) under the European Union{\textquoteright}s Horizon 2020 research and innovation programme (grant agreement No. 882793 “MeerGas”). This project has received funding from the European Research Council (ERC) under the European Union{\textquoteright}s Horizon 2020 research and innovation programme (grant agreement no. 679627; project name FORNAX). MAR acknowledges funding from the European Union{\textquoteright}s Horizon 2020 research and innovation programme under the Marie Sk{\l}odowska-Curie grant agreement No. 101066353 (project ELATE). A.L. has received support from the Science and Technologies Facilities Council (STFC) through their New Applicant grant ST/T000503/1. F.L. acknowledges financial support from the Italian Minister for Research and Education (MIUR), project FARE, project code R16PR59747, project name FORNAX-B. F.L. acknowledges financial support from the Italian Ministry of University and Research – Project Proposal CIR01_00010. P.K. is supported by the BMBF project 05A20PC4 for D-MeerKAT. The Legacy Surveys consist of three individual and complementary projects: the Dark Energy Camera Legacy Survey (DECaLS; Proposal ID #2014B-0404; PIs: David Schlegel and Arjun Dey), the Beijing-Arizona Sky Survey (BASS; NOAO Prop. ID #2015A-0801; PIs: Zhou Xu and Xiaohui Fan), and the Mayall z-band Legacy Survey (MzLS; Prop. ID #2016A-0453; PI: Arjun Dey). DECaLS, BASS and MzLS together include data obtained, respectively, at the Blanco telescope, Cerro Tololo Inter-American Observatory, NSF{\textquoteright}s NOIRLab; the Bok telescope, Steward Observatory, University of Arizona; and the Mayall telescope, Kitt Peak National Observatory, NOIRLab. The Legacy Surveys project is honored to be permitted to conduct astronomical research on Iolkam Du{\textquoteright}ag (Kitt Peak), a mountain with particular significance to the Tohono O{\textquoteright}odham Nation. NOIRLab is operated by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with the National Science Foundation. This project used data obtained with the Dark Energy Camera (DECam), which was constructed by the Dark Energy Survey (DES) collaboration. Funding for the DES Projects has been provided by the US Department of Energy, the US National Science Foundation, the Ministry of Science and Education of Spain, the Science and Technology Facilities Council of the United Kingdom, the Higher Education Funding Council for England, the National Center for Supercomputing Applications at the University of Illinois at Urbana-Champaign, the Kavli Institute of Cosmological Physics at the University of Chicago, Center for Cosmology and Astro-Particle Physics at the Ohio State University, the Mitchell Institute for Fundamental Physics and Astronomy at Texas A&M University, Financiadora de Estudos e Projetos, Fundacao Carlos Chagas Filho de Amparo, Financiadora de Estudos e Projetos, Fundacao Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro, Conselho Nacional de Desenvolvimento Cientifico e Tecnologico and the Ministerio da Ciencia, Tecnologia e Inovacao, the Deutsche Forschungsgemeinschaft and the Collaborating Institutions in the Dark Energy Survey. The Collaborating Institutions are Argonne National Laboratory, the University of California at Santa Cruz, the University of Cambridge, Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas-Madrid, the University of Chicago, University College London, the DES-Brazil Consortium, the University of Edinburgh, the Eidgenossische Technische Hochschule (ETH) Zurich, Fermi National Accelerator Laboratory, the University of Illinois at Urbana-Champaign, the Institut de Ciencies de l{\textquoteright}Espai (IEEC/CSIC), the Institut de Fisica d{\textquoteright}Altes Energies, Lawrence Berkeley National Laboratory, the Ludwig Maximilians Universitat Munchen and the associated Excellence Cluster Universe, the University of Michigan, NSF{\textquoteright}s NOIRLab, the University of Nottingham, the Ohio State University, the University of Pennsylvania, the University of Portsmouth, SLAC National Accelerator Laboratory, Stanford University, the University of Sussex, and Texas A&M University. BASS is a key project of the Telescope Access Program (TAP), which has been funded by the National Astronomical Observatories of China, the Chinese Academy of Sciences (the Strategic Priority Research Program “The Emergence of Cosmological Structures” Grant # XDB09000000), and the Special Fund for Astronomy from the Ministry of Finance. The BASS is also supported by the External Cooperation Program of Chinese Academy of Sciences (Grant # 114A11KYSB20160057), and Chinese National Natural Science Foundation (Grant # 11433005). The Legacy Survey team makes use of data products from the Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE), which is a project of the Jet Propulsion Laboratory/California Institute of Technology. NEOWISE is funded by the National Aeronautics and Space Administration. The Legacy Surveys imaging of the DESI footprint is supported by the Director, Office of Science, Office of High Energy Physics of the US Department of Energy under Contract No. DE-AC02-05CH1123, by the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility under the same contract; and by the US National Science Foundation, Division of Astronomical Sciences under Contract No. AST-0950945 to NOAO. Publisher Copyright: {\textcopyright} M. Duflot et al., published by EDP Sciences, 2023. ",
year = "2023",
month = jul,
doi = "10.1051/0004-6361/202346461",
language = "English",
volume = "675",
journal = "Astronomy and Astrophysics",
issn = "0004-6361",
publisher = " EDP Sciences",
}