Thermal SZ effect at the core of CL J1226.9+3332 revealed by NOEMA
M. Muñoz-Echeverría, J. -F. Macías-Pérez, R. Neri, E. Pointecouteau, R. Adam, P. Ade, H. Ajeddig, S. Amarantidis, P. André, H. Aussel, A. Beelen, A. Benoît, S. Berta, M. Béthermin, A. Bongiovanni, J. Bounmy, O. Bourrion, M. Calvo, A. Catalano, D. Chérouvrier, U. Chowdhury, M. De Petris, F. -X. Désert, S. Doyle, E. F. C. Driessen, G. Ejlali, A. Ferragamo, A. Gomez, J. Goupy, C. Hanser, S. Katsioli, F. Kéruzoré, C. Kramer, B. Ladjelate, G. Lagache, S. Leclercq, J. -F. Lestrade, S. C. Madden, A. Maury, F. Mayet, A. Monfardini, A. Moyer-Anin, I. Myserlis, A. Paliwal, L. Perotto, G. Pisano, N. Ponthieu, V. Revéret, A. J. Rigby, A. Ritacco, H. Roussel, F. Ruppin, M. Sánchez-Portal, S. Savorgnano, K. Schuster, A. Sievers, C. Tucker, R. Zylka, I. Bartalucci, J. -B. Melin, G. W. Pratt
Published: 2025/9/17
Abstract
We present first detailed maps of the thermal Sunyaev-Zel'dovich (tSZ) effect on a $z = 0.89$ cluster with the NOrthern Extended Millimeter Array (NOEMA). The high sensitivity of these observations enabled the effective identification and removal of the millimetre-wave sources contaminating the tSZ signal, thus isolating the influence of the cluster's hot electron gas on the cosmic microwave background radiation from other emissions. The tSZ observed with success by NOEMA is modelled together with previous single dish (IRAM 30-metre, Green Bank Telescope, and Caltech Sub-millimeter Observatory) observations to obtain the first core to outskirts (from $\sim$ 15 to $\sim$ 1500 kpc) pressure profile reconstruction on such a high redshift galaxy cluster. High angular resolution NOEMA observations have shown that the pressure profile is flat in the core of the cluster. These observations confirm the disturbed nature of CL J1226.9+3332 and map for the first time the distribution of its thermal gas at arcsecond scales, in the environments of the central cluster galaxy. Our results showcase NOEMA's excellent capabilities to complement and enhance the data provided by other millimetre-wave instruments in resolving the core of high-redshift clusters via tSZ emission.