Reconstructing the projected gravitational potential of galaxy clusters from galaxy kinematics

• Verfasst von: Sarli-Waizmann, Eleonora [VerfasserIn]
• Verfasst von: Meyer, Sven [VerfasserIn]
• Verfasst von: Meneghetti, Massimo [VerfasserIn]
• Verfasst von: Konrad, Sara [VerfasserIn]
• Verfasst von: Majer, Charles Ludwig [VerfasserIn]
• Verfasst von: Bartelmann, Matthias [VerfasserIn]
• Titel: Reconstructing the projected gravitational potential of galaxy clusters from galaxy kinematics
• Verf.angabe: Eleonora Sarli, Sven Meyer, Massimo Meneghetti, Sara Konrad, Charles L. Majer, and Matthias Bartelmann
• E-Jahr: 2014
• Jahr: 07 October 2014
• Umfang: 9 S.
• Teil: volume:570
• Teil: year:2014
• Teil: extent:9
• Fussnoten: Gesehen am 16.07.2020
• Titel Quelle: Enthalten in: Astronomy and astrophysics
• Ort Quelle: Les Ulis : EDP Sciences, 1969
• Jahr Quelle: 2014
• Band/Heft Quelle: 570(2014) Artikel-Nummer A9, 9 Seiten
• ISSN Quelle: 1432-0746
• DOI: doi:10.1051/0004-6361/201321748
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1724929577

Abstract

We have developed a method for reconstructing the two-dimensional, projected gravitational potential of galaxy clusters from observed line-of-sight velocity dispersions of cluster galaxies. It is the second in an intended series of papers aiming at a unique reconstruction method for cluster potentials that combine lensing, X-ray, Sunyaev-Zel’dovich and kinematic data. The observed galaxy velocity dispersions are deprojected using the Richardson-Lucy algorithm. The obtained radial velocity dispersions are then related to the gravitational potential by using the tested assumption of a polytropic relation between the effective galaxy pressure and the density. Once the gravitational potential is obtained in three dimensions, projection along the line of sight yields the two-dimensional potential. For simplicity we adopt spherical symmetry and a known profile for the anisotropy parameter of the galaxy velocity dispersions. We tested the method with a numerically simulated galaxy cluster and the galaxies identified therein and performed the reconstruction for three different lines of sight. We extracted a projected velocity-dispersion profile from the simulated cluster and passed it through our algorithm, showing that the deviation between the true and the reconstructed gravitational potential is ≲10% within ≈ 1.5 <i>h<i/><sup>-1<sup/> Mpc from the cluster centre.