Cluster cosmology with the NIKA2 SZ Large Program

F Mayet ,F Ruppin ,A Ritacco ,E F C Driessen ,F Kéruzoré ,A Bideaud ,N Ponthieu ,Peter A R Ade ,K Schüster ,G Lagache ,A Beelen ,H Roussel ,G Pisano ,J F Lestrade ,A Sievers ,I Bartalucci ,A Andrianasolo ,P André ,B Ladjelate ,H Aussel ,L Perotto ,J F Macías-Pérez ,M De Petris ,G W Pratt ,V Revéret ,O Bourrion ,R Adam ,C Tucker ,É Pointecouteau ,J Goupy ,S Doyle ,C Romero ,S Leclercq ,B Comis ,A Catalano ,M Arnaud ,Philip Daniel Mauskopf ,A Monfardini ,S Shu ,A Gómez ,C Krämer ,A Benoı̂t ,F.‐X Désert ,M Calvo ,R Zylka

doi:10.1051/epjconf/202022800017

Abstract

The main limiting factor of cosmological analyses based on thermal Sunyaev-Zel’dovich (SZ) cluster statistics comes from the bias and systematic uncertainties that affect the estimates of the mass of galaxy clusters. High-angular resolution SZ observations at high redshift are needed to study a potential redshift or morphology dependence of both the mean pressure profile and of the mass-observable scaling relation used in SZ cosmological analyses. The NIKA2 camera is a new generation continuum instrument installed at the IRAM 30-m telescope. With a large field of view, a high angular resolution and a high-sensitivity, the NIKA2 camera has unique SZ mapping capabilities. In this paper, we present the NIKA2 SZ large program, aiming at observing a large sample of clusters at redshifts between 0.5 and 0.9, and the characterization of the first cluster oberved with NIKA2.

Highlights

There is an increasing body of evidence of discrepancies between cosmological estimations obtained with early and late Universe probes [1, 2]
High-angular resolution SZ observations at high redshift are needed to study a potential redshift or morphology dependence of both the mean pressure profile and of the mass-observable scaling relation used in SZ cosmological analyses
The NIKA2 camera is a new generation continuum instrument installed at the IRAM 30-m telescope

Summary

Cluster cosmology: the need for high-angular resolution SZ observation

There is an increasing body of evidence of discrepancies between cosmological estimations obtained with early and late Universe probes [1, 2]. The thermal Sunyaev-Zel’dovich (SZ) effect plays a key role It is the inverse Compton scattering of CMB photons on hot electrons of the intra-cluster medium (ICM) [9]. Detailed information on the intra-cluster medium is needed to study the impact of dynamical state and morphology Both the calibration precision and scatter of the mass-observable scaling relation and of the mean pressure profile must be carefully studied in order to be included in forthcoming cluster cosmology analyses. One may write down an instrument wish list for SZ science aiming at cluster cosmology It includes: high angular resolution, in order to resolve inner structures, high sensitivity, to reduce integration time, large field of view, to map the cluster up to its outskirts, and dual band observation, to remove point-source contamination. These requirements correspond to the performance and characterics of the NIKA2 camera at the IRAM 30-m telescope [17,18,19] that makes it a powerful tool for SZ observations

The NIKA2 SZ large program

First cluster observation with NIKA2