Blind detection of galaxy clusters in the COSMOS field via the SZ effect

¹ Univ. Grenoble Alpes, CNRS, Grenoble INP, LPSC-IN2P3, 53, avenue des Martyrs, 38000 Grenoble, France
² Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, France
³ School of Physics and Astronomy, Cardiff University, Queen’s Buildings, The Parade, Cardiff, CF24 3AA, UK
⁴ Université Paris-Saclay, Université Paris Cité, CEA, CNRS, AIM, F-91191, Gif-sur-Yvette, France
⁵ Institut de Radioastronomie Millimétrique (IRAM), Avenida Divina Pastora 7, Local 20, E-18012, Granada, Spain
⁶ Instituto de Astrofísica de Canarias, C/ Vía Láctea s/n, E-38205 La Laguna, Tenerife, Spain
⁷ Universidad de La Laguna, Departamento de Astrofísica, E-38206 La Laguna, Tenerife, Spain
⁸ Aix Marseille Univ, CNRS, CNES, LAM (Laboratoire d’Astrophysique de Marseille), Marseille, France
⁹ Institut Néel, CNRS, Université Grenoble Alpes, France
¹⁰ Institut de Radioastronomie Millimétrique (IRAM), 300 rue de la Piscine, 38400 Saint-Martind’Hères, France
¹¹ Université de Strasbourg, CNRS, Observatoire astronomique de Strasbourg, UMR 7550, 67000 Strasbourg, France
¹² Astronomy Centre, Department of Physics and Astronomy, University of Sussex, Brighton BN1 9QH
¹³ Dipartimento di Fisica, Sapienza Università di Roma, Piazzale Aldo Moro 5, I-00185 Roma, Italy
¹⁴ Univ. Grenoble Alpes, CNRS, IPAG, 38000 Grenoble, France
¹⁵ Institute for Research in Fundamental Sciences (IPM), School of Astronomy, Tehran, Iran
¹⁶ Centro de Astrobiología (CSIC-INTA), Torrejón de Ardoz, 28850 Madrid, Spain
¹⁷ National Observatory of Athens, Institute for Astronomy, Astrophysics, Space Applications and Remote Sensing, Ioannou Metaxa and Vasileos Pavlou GR-15236, Athens, Greece
¹⁸ Department of Astrophysics, Astronomy & Mechanics, Faculty of Physics, University of Athens, Panepistimiopolis, GR-15784 Zografos, Athens, Greece
¹⁹ High Energy Physics Division, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, IL 60439, USA
²⁰ LERMA, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Université, UPMC, 75014 Paris, France
²¹ Institute of Space Sciences (ICE), CSIC, Campus UAB, Carrer de Can Magrans s/n, E-08193, Barcelona, Spain
²² ICREA, Pg. Lluís Companys 23, Barcelona, Spain
²³ Université Paris-Saclay, CEA, Département de Physique des Particules, 91191, Gif-sur-Yvette, France
²⁴ IRAP, CNRS, Université de Toulouse, CNES, UT3-UPS, (Toulouse), France
²⁵ Dipartimento di Fisica, Università di Roma ‘Tor Vergata’, Via della Ricerca Scientifica 1, I-00133 Roma, Italy
²⁶ School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK
²⁷ Institut d’Astrophysique de Paris, CNRS (UMR7095), 98 bis boulevard Arago, 75014 Paris, France
²⁸ University of Lyon, UCB Lyon 1, CNRS/IN2P3, IP2I, 69622 Villeurbanne, France

Published online: 20 February 2026

Abstract

Clusters of galaxies are powerful cosmological probes, and the thermal Sunyaev Zel’dovich (tSZ) effect provides an efficient method for their detection. High-angular-resolution observations, such as those provided by the NIKA2 camera on the IRAM 30-m telescope, are essential to target low mass and high-redshift clusters. We performed a blind search for galaxy clusters in the COSMOS field using 150 GHz data from the NIKA2 Cosmological Legacy Survey. We applied a matched-filter technique based on a universal pressure profile to extract cluster candidates. The purity and completeness of the sample were assessed using realistic simulations. We detected 16 cluster candidates above an S/N of 4, eight of which have confirmed counterparts.