Sunyaev-Zel'dovich Effect Observations of the Bullet Cluster (1E 0657-56) with APEX-SZ

@article{citeulike:3056463, abstract = {We present observations of the Sunyaev-Zel'dovich effect (SZE) in the Bullet cluster (1E 0657-56) using the APEX-SZ instrument at 150 GHz with a resolution of 1 arcmin. The main results are maps of the SZE in this massive, merging galaxy cluster. The cluster is detected with 23 sigma significance within the central 1 arcmin radius of the source position. The SZE map has a broadly similar morphology to that in existing X-ray maps of this system, and we find no evidence for significant contamination of the SZE emission by radio or IR sources. In order to make simple quantitative comparisons with cluster gas models derived from X-ray observations, we fit our data to an isothermal elliptical beta model, despite the inadequacy of such a model for this complex merging system. With an X-ray derived prior on the power-law index, beta = 1.04 +0.16/-0.10, we find a core radius r\_c =144 +/- 19 arcsec, an axial ratio of 0.881 +/- 0.086, and a central temperature decrement of -880 +/- 80 micro-K\_CMB, including a +/- 6\% flux calibration uncertainty. These model parameters are consistent with the values determined from X-ray data. Under the assumption of an isothermal cluster gas distribution in hydrostatic equilibrium, we compute the gas mass fraction for prolate and oblate spheroidal geometries, and the mass-weighted electron temperature of the cluster. This work is the first result from the APEX-SZ experiment, and represents the first published scientific result from observations with a large array of multiplexed superconducting transition-edge sensor bolometers.}, author = {Halverson, N. W. and Lanting, T. and Ade, P. A. R. and Basu, K. and Bender, A. N. and Benson, B. A. and Bertoldi, F. and Cho, H. M. and Chon, G. and Clarke, J. and Dobbs, M. and Ferrusca, D. and Guesten, R. and Holzapfel, W. L. and Kovacs, A. and Kennedy, J. and Kermish, Z. and Kneissl, R. and Lee, A. T. and Lueker, M. and Mehl, J. and Menten, K. M. and Muders, D. and Nord, M. and Pacaud, F. and Plagge, T. and Reichardt, C. and Richards, P. L. and Schaaf, R. and Schilke, P. and Schuller, F. and Schwan, D. and Spieler, H. and Tucker, C. and Weiss, A. and Zahn, O. }, citeulike-article-id = {3056463}, eprint = {0807.4208}, keywords = {boulder, sz}, month = {Jul}, posted-at = {2008-07-29 15:48:05}, priority = {2}, title = {Sunyaev-Zel'dovich Effect Observations of the Bullet Cluster (1E 0657-56) with APEX-SZ}, url = {http://arxiv.org/abs/0807.4208}, year = {2008} }

TY - JOUR ID - citeulike:3056463 L3 - citeulike-article-id:3056463 TI - Sunyaev-Zel'dovich Effect Observations of the Bullet Cluster (1E 0657-56) with APEX-SZ N2 - We present observations of the Sunyaev-Zel'dovich effect (SZE) in the Bullet cluster (1E 0657-56) using the APEX-SZ instrument at 150 GHz with a resolution of 1 arcmin. The main results are maps of the SZE in this massive, merging galaxy cluster. The cluster is detected with 23 sigma significance within the central 1 arcmin radius of the source position. The SZE map has a broadly similar morphology to that in existing X-ray maps of this system, and we find no evidence for significant contamination of the SZE emission by radio or IR sources. In order to make simple quantitative comparisons with cluster gas models derived from X-ray observations, we fit our data to an isothermal elliptical beta model, despite the inadequacy of such a model for this complex merging system. With an X-ray derived prior on the power-law index, beta = 1.04 +0.16/-0.10, we find a core radius r_c =144 +/- 19 arcsec, an axial ratio of 0.881 +/- 0.086, and a central temperature decrement of -880 +/- 80 micro-K_CMB, including a +/- 6% flux calibration uncertainty. These model parameters are consistent with the values determined from X-ray data. Under the assumption of an isothermal cluster gas distribution in hydrostatic equilibrium, we compute the gas mass fraction for prolate and oblate spheroidal geometries, and the mass-weighted electron temperature of the cluster. This work is the first result from the APEX-SZ experiment, and represents the first published scientific result from observations with a large array of multiplexed superconducting transition-edge sensor bolometers. KW - boulder KW - sz AU - Halverson, NW AU - Lanting, T AU - Ade, PAR AU - Basu, K AU - Bender, AN AU - Benson, BA AU - Bertoldi, F AU - Cho, HM AU - Chon, G AU - Clarke, J AU - Dobbs, M AU - Ferrusca, D AU - Guesten, R AU - Holzapfel, WL AU - Kovacs, A AU - Kennedy, J AU - Kermish, Z AU - Kneissl, R AU - Lee, AT AU - Lueker, M AU - Mehl, J AU - Menten, KM AU - Muders, D AU - Nord, M AU - Pacaud, F AU - Plagge, T AU - Reichardt, C AU - Richards, PL AU - Schaaf, R AU - Schilke, P AU - Schuller, F AU - Schwan, D AU - Spieler, H AU - Tucker, C AU - Weiss, A AU - Zahn, O PY - 2008/Jul/26/ UR - http://arxiv.org/abs/0807.4208 ER -