# Non-parametric deprojection of NIKA SZ observations: pressure distribution in the Planck-discovered cluster PSZ1 G045.85+57.71

6 Cryo - Cryogénie
NEEL - Institut Néel
Abstract : The determination of the thermodynamic properties of clusters of galaxies at intermediate and high redshift can bring new insights into the formation of large scale structures. It is essential for a robust calibration of the mass-observable scaling relations and their scatter, which are key ingredients for precise cosmology using cluster statistics. Here we illustrate an application of high-resolution $(< 20$ arcsec) thermal Sunyaev-Zel'dovich (tSZ) observations by probing the intracluster medium (ICM) of the Planck-discovered galaxy cluster PSZ1 G045.85+57.71 at redshift $z = 0.61$, using tSZ data obtained with the NIKA camera, a dual-band (150 and 260~GHz) instrument operated at the IRAM 30-meter telescope. We deproject jointly NIKA and Planck data to extract the electronic pressure distribution non-parametrically from the cluster core ($R \sim 0.02\, R_{500}$) to its outskirts ($R \sim 3\, R_{500}$), for the first time at intermediate redshift. The constraints on the resulting pressure profile allow us to reduce the relative uncertainty on the integrated Compton parameter by a factor of two compared to the Planck value. Combining the tSZ data and the deprojected electronic density profile from XMM-Newton allows us to undertake a hydrostatic mass analysis, for which we study the impact of a spherical model assumption on the total mass estimate. We also investigate the radial temperature and entropy distributions. These data indicate that PSZ1 G045.85+57.71 is a massive ($M_{500} \sim 5.5 \times 10^{14}$ M$_{\odot}$) cool-core cluster. This work is part of a pilot study aimed at optimising the treatment of the NIKA2 tSZ Large Programme dedicated to the follow-up of SZ-discovered clusters at intermediate and high redshifts. (abridged)
Document type :
Journal articles

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Submitted on : Wednesday, July 27, 2016 - 4:34:15 PM
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### Citation

F. Ruppin, R. Adam, B. Comis, P. Ade, P. André, et al.. Non-parametric deprojection of NIKA SZ observations: pressure distribution in the Planck-discovered cluster PSZ1 G045.85+57.71. Astronomy and Astrophysics - A&A, EDP Sciences, 2017, 597, pp.A110. ⟨10.1051/0004-6361/201629405 ⟩. ⟨in2p3-01349507⟩

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