Reconstructing the projected gravitational potential of galaxy clusters from galaxy kinematics
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 potentia...
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| Main Authors: | , , , , , |
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| Format: | Article (Journal) |
| Language: | English |
| Published: |
07 October 2014
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| In: |
Astronomy and astrophysics
Year: 2014, Volume: 570 |
| ISSN: | 1432-0746 |
| DOI: | 10.1051/0004-6361/201321748 |
| Online Access: | Verlag, lizenzpflichtig, Volltext: https://doi.org/10.1051/0004-6361/201321748 Verlag, lizenzpflichtig, Volltext: https://www.aanda.org/articles/aa/abs/2014/10/aa21748-13/aa21748-13.html 
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| Author Notes: | Eleonora Sarli, Sven Meyer, Massimo Meneghetti, Sara Konrad, Charles L. Majer, and Matthias Bartelmann |
| Summary: | 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. |
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| Item Description: | Gesehen am 16.07.2020 |
| Physical Description: | Online Resource |
| ISSN: | 1432-0746 |
| DOI: | 10.1051/0004-6361/201321748 |