Reconstruction of the two-dimensional gravitational potential of galaxy clusters from X-ray and Sunyaev-Zel’dovich measurements

• Verfasst von: Tchernin, Céline [VerfasserIn]
• Verfasst von: Bartelmann, Matthias [VerfasserIn]
• Verfasst von: Majer, Charles Ludwig [VerfasserIn]
• Verfasst von: Meyer, Sven [VerfasserIn]
• Titel: Reconstruction of the two-dimensional gravitational potential of galaxy clusters from X-ray and Sunyaev-Zel’dovich measurements
• Verf.angabe: C. Tchernin, M. Bartelmann, K. Huber, A. Dekel, G. Hurier, C.L. Majer, S. Meyer, E. Zinger, D. Eckert, M. Meneghetti, J. Merten
• E-Jahr: 2018
• Jahr: 12 June 2018
• Umfang: 15 S.
• Fussnoten: Gesehen am 09.05.2019
• Titel Quelle: Enthalten in: Astronomy and astrophysics
• Ort Quelle: Les Ulis : EDP Sciences, 1969
• Jahr Quelle: 2018
• Band/Heft Quelle: 614(2018) Artikel-Nummer A38, 15 Seiten
• ISSN Quelle: 1432-0746
• DOI: doi:10.1051/0004-6361/201629364
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1665052325

Abstract

The mass of galaxy clusters is not a direct observable, nonetheless it is commonly used to probe cosmological models. Based on the combination of all main cluster observables, that is, the X-ray emission, the thermal Sunyaev-Zel’dovich (SZ) signal, the velocity dispersion of the cluster galaxies, and gravitational lensing, the gravitational potential of galaxy clusters can be jointly reconstructed.<i>Aims.<i/> We derive the two main ingredients required for this joint reconstruction: the potentials individually reconstructed from the observables and their covariance matrices, which act as a weight in the joint reconstruction. We show here the method to derive these quantities. The result of the joint reconstruction applied to a real cluster will be discussed in a forthcoming paper.<i>Methods.<i/> We apply the Richardson-Lucy deprojection algorithm to data on a two-dimensional (2D) grid. We first test the 2D deprojection algorithm on a <i>β<i/>-profile. Assuming hydrostatic equilibrium, we further reconstruct the gravitational potential of a simulated galaxy cluster based on synthetic SZ and X-ray data. We then reconstruct the projected gravitational potential of the massive and dynamically active cluster Abell 2142, based on the X-ray observations collected with <i>XMM-Newton<i/> and the SZ observations from the <i>Planck<i/> satellite. Finally, we compute the covariance matrix of the projected reconstructed potential of the cluster Abell 2142 based on the X-ray measurements collected with <i>XMM-Newton<i/>.<i>Results.<i/> The gravitational potentials of the simulated cluster recovered from synthetic X-ray and SZ data are consistent, even though the potential reconstructed from X-rays shows larger deviations from the true potential. Regarding Abell 2142, the projected gravitational cluster potentials recovered from SZ and X-ray data reproduce well the projected potential inferred from gravitational-lensing observations. We also observe that the covariance matrix of the potential for Abell 2142 reconstructed from <i>XMM-Newton<i/> data sensitively depends on the resolution of the deprojected grid and on the smoothing scale used in the deprojection.<i>Conclusions.<i/> We show that the Richardson-Lucy deprojection method can be effectively applied on a grid and that the projected potential is well recovered from real and simulated data based on X-ray and SZ signal. The comparison between the reconstructed potentials from the different observables provides additional information on the validity of the assumptions as function of the projected radius.