The SZ-Mass scaling relation with the NIKA2 SZ Large Program

¹ Univ. Grenoble Alpes, CNRS, LPSC-IN2P3, 53, av. 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 Cité, Université Paris-Saclay, CEA, CNRS, AIM, F-91191 Gif-sur-Yvette, France
⁵ INAF, IASF-Milano, Via A. Corti 12, 20133 Milano, Italy.
⁶ Institut de Radioastronomie Millimétrique (IRAM), Avenida Divina Pastora 7, Local 20, E-18012, Granada, Spain
⁷ Aix Marseille Univ, CNRS, CNES, LAM (Laboratoire d’Astrophysique de Marseille), Marseille, France
⁸ Institut Néel, CNRS, Université Grenoble Alpes, France
⁹ Institut de RadioAstronomie Millimétrique (IRAM), Grenoble, France
¹⁰ Université de Strasbourg, CNRS, Observatoire astronomique de Strasbourg, UMR 7550, 67000 Strasbourg, France
¹¹ DAMTP, Centre for Mathematical Sciences, Wilberforce Road, Cambridge CB3 0WA, U.K.
¹² Dipartimento di Fisica, Sapienza Università di Roma, Piazzale Aldo Moro 5, I-00185 Roma, Italy
¹³ Univ. Grenoble Alpes, CNRS, IPAG, 38000 Grenoble, France
¹⁴ Institute for Research in Fundamental Sciences (IPM), School of Astronomy, Tehran, Iran
¹⁵ Centro de Astrobiología (CSIC-INTA), Torrejón de Ardoz, 28850 Madrid, Spain
¹⁶ Aix Marseille Univ, CNRS/IN2P3, CPPM, Marseille, France
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 Av., 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
²⁹ Departamento de Física Teórica and CIAFF, Facultad de Ciencias, Univ. Autónoma de Madrid, 28049 Madrid, Spain.

Published online: 20 February 2026

Abstract

In Sunyaev-Zeldovich (SZ) cluster cosmology, accurately determining cluster masses is crucial for constraining cosmological parameters through cluster number counts. As the mass is not an observable, a scaling relation is needed to link cluster masses to the integrated Compton parameter Y, i.e., the SZ observable, to exploit data from large millimeter surveys. Former cosmological results use a scaling relation obtained with clusters at low redshift (z < 0.5) observed in X-ray and in SZ at an angular resolution above 1 arcminute. The SZ large program (LPSZ) of the NIKA2 collaboration uses a sample of clusters at intermediate to high redshift (from z = 0.5 to z = 0.9) observed at similarly high-angular resolution both in SZ and in X-ray. We present the SZ-Mass scaling relation parameters calibrated thanks to the LPSZ data.