Reconstructing the projected gravitational potential of galaxy clusters from galaxy kinematics
We develop 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 third of an intended series of papers aiming at a unique reconstruction method for cluster potentials combi...
Saved in:
| Main Authors: | , , , , , |
|---|---|
| Format: | Article (Journal) Chapter/Article |
| Language: | English |
| Published: |
29 Apr 2013
|
| In: |
Arxiv
|
| Online Access: | Verlag, kostenfrei, Volltext: http://arxiv.org/abs/1304.7681
|
| Author Notes: | Eleonora Sarli, Sven Meyer, Massimo Meneghetti, Sara Konrad, Charles L. Majer, and Matthias Bartelmann |
| Summary: | We develop 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 third of an intended series of papers aiming at a unique reconstruction method for cluster potentials combining 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 test the method with a numerically simulated galaxy cluster and galaxies identified therein. We extract a projected velocity-dispersion profile from the simulated cluster and pass it through our algorithm, showing that the deviation between the true and the reconstructed gravitational potential is less then 10% within approximately 1.2 Mpc/h from the cluster centre. |
|---|---|
| Item Description: | Gesehen am 19.09.2017 |
| Physical Description: | Online Resource |