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A high-resolution view of the filament of gas between Abell 399 and Abell 401 from the Atacama Cosmology Telescope and MUSTANG-2

Hincks, Adam D. and Radiconi, Federico and Romero, Charles and Madhavacheril, Mathew S. and Mroczkowski, Tony and Austermann, Jason E. and Barbavara, Eleonora and Battaglia, Nicholas and Battistelli, Elia and Bond, J. Richard and Calabrese, Erminia and de Bernardis, Paolo and Devlin, Mark J. and Dicker, Simon R. and Duff, Shannon M. and Duivenvoorden, Adriaan J. and Dunkley, Jo and Dünner, Rolando and Gallardo, Patricio A. and Govoni, Federica and Hill, J. Colin and Hilton, Matt and Hubmayr, Johannes and Hughes, John P. and Lamagna, Luca and Lokken, Martine and Masi, Silvia and Mason, Brian S. and McMahon, Jeff and Moodley, Kavilan and Murgia, Matteo and Naess, Sigurd and Page, Lyman and Piacentini, Francesco and Salatino, Maria and Sarazin, Craig L. and Schillaci, Alessandro and Sievers, Jonathan L. and Sifón, Cristóbal and Staggs, Suzanne and Ullom, Joel N. and Vacca, Valentina and Van Engelen, Alexander and Vissers, Michael R. and Wollack, Edward J. and Xu, Zhilei (2022) A high-resolution view of the filament of gas between Abell 399 and Abell 401 from the Atacama Cosmology Telescope and MUSTANG-2. Monthly Notices of the Royal Astronomical Society, 510 (3). pp. 3335-3355. ISSN 0035-8711. doi:10.1093/mnras/stab3391.

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We report a significant detection of the hot intergalactic medium in the filamentary bridge connecting the galaxy clusters Abell 399 and Abell 401. This result is enabled by a low-noise, high-resolution map of the thermal Sunyaev–Zeldovich signal from the Atacama Cosmology Telescope (ACT) and Planck satellite. The ACT data provide the 1.65 arcmin resolution that allows us to clearly separate the profiles of the clusters, whose centres are separated by 37 arcmin, from the gas associated with the filament. A model that fits for only the two clusters is ruled out compared to one that includes a bridge component at >5σ. Using a gas temperature determined from Suzaku X-ray data, we infer a total mass of (3.3±0.7)×10¹⁴M⊙ associated with the filament, comprising about 8 per cent of the entire Abell 399–Abell 401 system. We fit two phenomenological models to the filamentary structure; the favoured model has a width transverse to the axis joining the clusters of ∼1.9Mpc⁠. When combined with the Suzaku data, we find a gas density of (0.88±0.24)×10⁻⁴cm⁻³, considerably lower than previously reported. We show that this can be fully explained by a geometry in which the axis joining Abell 399 and Abell 401 has a large component along the line of sight, such that the distance between the clusters is significantly greater than the 3.2Mpc projected separation on the plane of the sky. Finally, we present initial results from higher resolution (12.7 arcsec effective) imaging of the bridge with the MUSTANG-2 receiver on the Green Bank Telescope.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Hincks, Adam D.0000-0003-1690-6678
Madhavacheril, Mathew S.0000-0001-6740-5350
Mroczkowski, Tony0000-0003-3816-5372
Austermann, Jason E.0000-0002-6338-0069
Battaglia, Nicholas0000-0001-5846-0411
Battistelli, Elia0000-0001-5210-7625
Bond, J. Richard0000-0003-2358-9949
Calabrese, Erminia0000-0003-0837-0068
Devlin, Mark J.0000-0002-3169-9761
Dicker, Simon R.0000-0002-1940-4289
Duff, Shannon M.0000-0002-9693-4478
Duivenvoorden, Adriaan J.0000-0003-2856-2382
Dunkley, Jo0000-0002-7450-2586
Gallardo, Patricio A.0000-0001-9731-3617
Hill, J. Colin0000-0002-9539-0835
Hilton, Matt0000-0002-8490-8117
Hubmayr, Johannes0000-0002-2781-9302
Hughes, John P.0000-0002-8816-6800
Mason, Brian S.0000-0002-8472-836X
McMahon, Jeff0000-0002-7245-4541
Moodley, Kavilan0000-0001-6606-7142
Murgia, Matteo0000-0002-4800-0806
Naess, Sigurd0000-0002-4478-7111
Page, Lyman0000-0002-9828-3525
Salatino, Maria0000-0003-4006-1134
Schillaci, Alessandro0000-0002-0512-1042
Sifón, Cristóbal0000-0002-8149-1352
Staggs, Suzanne0000-0002-7020-7301
Ullom, Joel N.0000-0003-2486-4025
Vacca, Valentina0000-0003-1997-0771
Wollack, Edward J.0000-0002-7567-4451
Xu, Zhilei0000-0001-5112-2567
Additional Information:© 2021 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model ( Accepted 2021 November 16. Received 2021 November 10; in original form 2021 July 9. Published: 26 November 2021. We thank Hiroki Akamatsu for his gracious and patient assistance in tracking down and correcting an algebraic error in Akamatsu et al. (2017) (see Appendix B). We also thank Victor Bonjean and Nabila Aghanim for their help in understanding details from their work in Bonjean et al. (2018). We are grateful to the journal’s scientific editor, Joop Schaye, and an anonymous referee for helpful suggestions. This work was supported by the U.S. National Science Foundation (NSF) through awards AST-0408698, AST-0965625, and AST-1440226 for the ACT project, as well as awards PHY-0355328, PHY-0855887 and PHY-1214379. Funding was also provided by Princeton University, the University of Pennsylvania, and a Canada Foundation for Innovation (CFI) award to UBC. ACT operates in the Parque Astronómico Atacama in northern Chile under the auspices of the La Agencia Nacional de Investigación y Desarrollo (ANID; formerly Comisión Nacional de Investigación Científica y Tecnológica de Chile, or CONICYT). The development of multichroic detectors and lenses was supported by National Aeronautics and Space Administration (NASA) grants NNX13AE56G and NNX14AB58G. Detector research at the National Institute of Standards and Technology (NIST) was supported by the NIST Innovations in Measurement Science program. Computations were performed on Cori at the National Energy Research Scientific Computing Center (NERSC) as part of the CMB Community allocation, on the Niagara supercomputer at the SciNet High Performance Computing Consortium, and on Feynman and Tiger at Princeton Research Computing, and on the hippo cluster at the University of KwaZulu-Natal. SciNet is funded by the CFI under the auspices of Compute Canada, the Government of Ontario, the Ontario Research Fund–Research Excellence, and the University of Toronto. Colleagues at AstroNorte and RadioSky provide logistical support and keep operations in Chile running smoothly. We also thank the Mishrahi Fund and the Wilkinson Fund for their generous support of the project. MUSTANG2 is supported by the NSF award number 1615604 and by the Mt. Cuba Astronomical Foundation. The Green Bank Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. GBT data were taken under the project ID AGBT_19B_095. ADH is grateful for support from the Sutton Family Chair in Science, Christianity and Cultures. CS acknowledges support from the Agencia Nacional de Investigación y Desarrollo (ANID) under Fondo Nacional de Desarrollo Científico y Tecnológico (FONDECYT) grant no. 11191125. EC acknowledges support from the Science and Technology Facilities Council (STFC) Ernest Rutherford Fellowship ST/M004856/2 and STFC Consolidated Grant ST/S00033X/1, and from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant agreement No. 849169). JLS acknowledges support from the Canada 150 Programme and an NSERC Discovery Grant. JPH acknowledges funding for SZ cluster studies from NSF AAG number AST-1615657. KM acknowledges support from the National Research Foundation of South Africa. VV acknowledges support from Istituto Nazionale di Astrofisica (INAF) mainstream project ‘Galaxy Clusters Science with LOFAR’ ZX is supported by the Gordon and Betty Moore Foundation. This research has made use of the NASA/IPAC Extragalactic Database (NED), which is funded by the National Aeronautics and Space Administration and operated by the California Institute of Technology. Some of the results/plots in this paper have been derived/produced using the following software: APLPY, an open-source plotting package for Python (Robitaille & Bressert 2012; Robitaille 2019); ASTROPY,28 a community-developed core Python package for Astronomy (Astropy Collaboration 2013, 2018); DS9 (Joye & Mandel 2003); EMCEE (Foreman-Mackey et al. 2013); GNUPLOT,29HEALPIX30 (Górski et al. 2005), and HEALPY (Zonca et al. 2019); MATPLOTLIB (Hunter 2007); NUMPY (Harris et al. 2020); PANDAS (Wes McKinney 2010); PIXELL;31 and SCIPY (Virtanen et al. 2020). Data Availability: The ACT y-map used in this paper will be released on the NASA Legacy Archive Microwave Background Data Analysis (LAMBDA) website.32 The MUSTANG-2 map used in this paper will be released on LAMBDA and/or the Harvard Dataverse.33
Group:Infrared Processing and Analysis Center (IPAC)
Funding AgencyGrant Number
Princeton UniversityUNSPECIFIED
University of PennsylvaniaUNSPECIFIED
Canada Foundation for InnovationUNSPECIFIED
National Institute of Standards and Technology (NIST)UNSPECIFIED
Government of OntarioUNSPECIFIED
Ontario Research Fund-Research ExcellenceUNSPECIFIED
University of TorontoUNSPECIFIED
Mt. Cuba Astronomical FoundationUNSPECIFIED
Sutton Family Chair in Science, Christianity and CulturesUNSPECIFIED
Agencia Nacional de Investigación y Desarrollo (ANID)UNSPECIFIED
Fondo Nacional de Desarrollo Científico y Tecnológico (FONDECYT)11191125
Science and Technology Facilities Council (STFC)ST/M004856/2
Science and Technology Facilities Council (STFC)ST/S00033X/1
European Research Council (ERC)849169
Canada 150 ProgrammeUNSPECIFIED
Natural Sciences and Engineering Research Council of Canada (NSERC)UNSPECIFIED
National Research Foundation (South Africa)UNSPECIFIED
Istituto Nazionale di Astrofisica (INAF)UNSPECIFIED
Gordon and Betty Moore FoundationUNSPECIFIED
Subject Keywords:galaxies: clusters: indi vidual: Abell 399 –galaxies: clusters: individual: Abell 401 –galaxies: clusters: intracluster medium –cosmic background radiation –cosmology: observations –large-scale structure of Universe
Issue or Number:3
Record Number:CaltechAUTHORS:20220419-740045500
Persistent URL:
Official Citation:Adam D Hincks, Federico Radiconi, Charles Romero, Mathew S Madhavacheril, Tony Mroczkowski, Jason E Austermann, Eleonora Barbavara, Nicholas Battaglia, Elia Battistelli, J Richard Bond, Erminia Calabrese, Paolo de Bernardis, Mark J Devlin, Simon R Dicker, Shannon M Duff, Adriaan J Duivenvoorden, Jo Dunkley, Rolando Dünner, Patricio A Gallardo, Federica Govoni, J Colin Hill, Matt Hilton, Johannes Hubmayr, John P Hughes, Luca Lamagna, Martine Lokken, Silvia Masi, Brian S Mason, Jeff McMahon, Kavilan Moodley, Matteo Murgia, Sigurd Naess, Lyman Page, Francesco Piacentini, Maria Salatino, Craig L Sarazin, Alessandro Schillaci, Jonathan L Sievers, Cristóbal Sifón, Suzanne Staggs, Joel N Ullom, Valentina Vacca, Alexander Van Engelen, Michael R Vissers, Edward J Wollack, Zhilei Xu, A high-resolution view of the filament of gas between Abell 399 and Abell 401 from the Atacama Cosmology Telescope and MUSTANG-2, Monthly Notices of the Royal Astronomical Society, Volume 510, Issue 3, March 2022, Pages 3335–3355,
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:114374
Deposited By: Tony Diaz
Deposited On:19 Apr 2022 18:17
Last Modified:19 Apr 2022 18:17

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