Pressure distribution of the high-redshift cluster of galaxies CL J1226.9+3332 with NIKA
Adam, R.; Benoît, A.; Catalano, A.; Désert, F. -X.; Pajot, F.; Perotto, L.; Pointecouteau, E.; Savini, G.; Rodriguez, L.; Billot, N.; Kramer, C.; André, P.; Beelen, A.; Ade, P.; Bourrion, O.; Calvo, M.; Doyle, S.; Goupy, J.; Leclercq, S.; Mauskopf, P.; Mayet, F.; Monfardini, A.; Ponthieu, N.; Revéret, V.; Ritacco, A.; Schuster, K.; Sievers, A.; Tucker, C.; Zylka, R.; Bideaud, A.; Coiffard, G.; Comis, B.; D'Addabbo, A.; Pascale, E.; Martino, J.; Macías-Pérez, J. -F.; Cruciani, A.; Adane, A.; Belier, B.; Blanquer, G.
France, United Kingdom, Spain, Italy, United States
Abstract
The thermal Sunyaev-Zel'dovich (tSZ) effect is expected to provide a low scatter mass proxy for galaxy clusters since it is directly proportional to the cluster thermal energy. The tSZ observations have proven to be a powerful tool for detecting and studying them, but high angular resolution observations are now needed to push their investigation to a higher redshift. In this paper, we report high angular (<20 arcsec) resolution tSZ observations of the high-redshift cluster CL J1226.9+3332 (z = 0.89). It was imaged at 150 and 260 GHz using the NIKA camera at the IRAM 30-m telescope. The 150 GHz map shows that CL J1226.9+3332 is morphologically relaxed on large scales with evidence of a disturbed core, while the 260 GHz channel is used mostly to identify point source contamination. NIKA data are combined with those of Planck and X-ray from Chandra to infer the cluster's radial pressure, density, temperature, and entropy distributions. The total mass profile of the cluster is derived, and we find M500 = 5.96+1.02-0.79 × 1014M⊙ within the radius R500 = 930+50-43 kpc, at a 68% confidence level. (R500 is the radius within which the average density is 500 times the critical density at the cluster's redshift.) NIKA is the prototype camera of NIKA2, a KIDs (kinetic inductance detectors) based instrument to be installed at the end of 2015. This work is, therefore, part of a pilot study aiming at optimizing tSZ NIKA2 large programs.
The FITS file of the published maps is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/576/A12