* Astronomy

Blobrana · L

RE: SPT-CL J0546-5345

Blobrana · L

Astronomers today said they found a massive space system known as a galaxy cluster 7 billion light-years away from Earth that holds hundreds of galaxies and weighs in at around 800 trillion Suns.
The cluster, designated SPT-CL J0546-5345, seen at 7 billion light years away would be four times larger in real time making it one of the most massive galaxy clusters in the universe, astronomers claim.
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Blobrana · L

Title: SPT-CL J0546-5345: A Massive z > 1 Galaxy Cluster Selected Via the Sunyaev-Zel'dovich Effect with the South Pole Telescope
Authors: M. Brodwin, J. Ruel, P. A. R. Ade, K. A. Aird, K. Andersson, M. L. N. Ashby, M. Bautz, G. Bazin, B. A. Benson, L. E. Bleem, J. E. Carlstrom, C. L. Chang, T. M. Crawford, A. T. Crites, T. de Haan, S. Desai, M. A. Dobbs, J. P. Dudley, G. G. Fazio, R. J. Foley, W. R. Forman, G. Garmire, E. M. George, M. D. Gladders, A. H. Gonzalez, N. W. Halverson, F. W. High, G. P. Holder, W. L. Holzapfel, J. D. Hrubes, C. Jones, M. Joy, R. Keisler, L. Knox, A. T. Lee, E. M. Leitch, M. Lueker, D. P. Marrone, J. J. McMahon, J. Mehl, S. S. Meyer, J. J. Mohr, T. E. Montroy, S. S. Murray, S. Padin, T. Plagge, C. Pryke, C. L. Reichardt, A. Rest, J. E. Ruhl, K. K. Schaffer, L. Shaw, E. Shirokoff, J. Song, H. G. Spieler, B. Stalder, S. A. Stanford, Z. Staniszewski, A. A. Stark, C. W. Stubbs, K. Vanderlinde, J. D. Vieira,
A. Vikhlinin, R. Williamson, Y. Yang, O. Zahn, A. Zenteno
et al. (5 additional authors not shown)
(Version v2)

We report the spectroscopic confirmation of SPT-CL J0546-5345 at <z> = 1.067. To date this is the most distant cluster to be spectroscopically confirmed from the 2008 South Pole Telescope (SPT) catalogue, and indeed the first z > 1 cluster discovered by the Sunyaev-Zel'dovich Effect (SZE). We identify 21 secure spectroscopic members within 0.9 Mpc of the SPT cluster position, 18 of which are quiescent, early-type galaxies. From these quiescent galaxies we obtain a velocity dispersion of 1179^{+232}_{-167} km/s, ranking SPT-CL J0546-5345 as the most dynamically massive cluster yet discovered at z > 1. Assuming that SPT-CL J0546-5345 is virialised, this implies a dynamical mass of M_200 = 1.0^{+0.6}_{-0.4} x 10^{15} Msun, in agreement with the X-ray and SZE mass measurements. Combining masses from several independent measures leads to a best-estimate mass of M_200 = (7.95 ±0.92) x 10^{14} Msun. The spectroscopic confirmation of SPT-CL J0546-5345, discovered in the wide-angle, mass-selected SPT cluster survey, marks the onset of the high redshift SZE-selected galaxy cluster era.

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Blobrana · L

Title: SPT-CL J0546-5345: A Massive z > 1 Galaxy Cluster Selected Via the Sunyaev-Zel'dovich Effect with the South Pole Telescope
Authors: M. Brodwin, J. Ruel, P. A. R. Ade, K. A. Aird, K. Andersson, M. L. N. Ashby, M. Bautz, G. Bazin, B. A. Benson, L. E. Bleem, J. E. Carlstrom, C. L. Chang, T. M. Crawford, A. T. Crites, T. de Haan, S. Desai, M. A. Dobbs, J. P. Dudley, G. G. Fazio, R. J. Foley, W. R. Forman, G. Garmire, E. M. George, M. D. Gladders, A. H. Gonzalez, N. W. Halverson, F. W. High, G. P. Holder, W. L. Holzapfel, J. D. Hrubes, C. Jones, M. Joy, R. Keisler, L. Knox, A. T. Lee, E. M. Leitch, M. Lueker, D. P. Marrone, J. J. McMahon, J. Mehl, S. S. Meyer, J. J. Mohr, T. E. Montroy, S. S. Murray, S. Padin, T. Plagge, C. Pryke, C. L. Reichardt, A. Rest, J. E. Ruhl, K. K. Schaffer, L. Shaw, E. Shirokoff, J. Song, H. G. Spieler, B. Stalder, S. A. Stanford, Z. Staniszewski, A. A. Stark, C. W. Stubbs, K. Vanderlinde, J. D. Vieira,
A. Vikhlinin, R. Williamson, Y. Yang, O. Zahn, A. Zenteno
et al. (5 additional authors not shown)

We report the spectroscopic confirmation of SPT-CL J0546-5345 at = 1.067. To date this is the most distant cluster to be spectroscopically confirmed from the 2008 South Pole Telescope (SPT) catalogue, and indeed the first z > 1 cluster discovered by the Sunyaev-Zel'dovich Effect (SZE). We identify 21 secure spectroscopic members within 0.9 Mpc of the SPT cluster position, 18 of which are quiescent, early-type galaxies. From these quiescent galaxies we obtain a velocity dispersion of 1179^{+232}_{-167} km/s, ranking SPT-CL J0546-5345 as the most dynamically massive cluster yet discovered at z > 1. Assuming that SPT-CL J0546-5345 is virialised, this implies a dynamical mass of M_200 = 1.0^{+0.6}_{-0.4} x 10^{15} Msun, in agreement with the X-ray and SZE mass measurements. The spectroscopic confirmation of SPT-CL J0546-5345, discovered in the wide-angle, mass-selected SPT cluster survey, marks the onset of the high redshift SZE-selected galaxy cluster era.

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