A joint analysis of AMI and CARMA observations of the recently discovered SZ galaxy cluster system AMI-CL J0300+2613

作者:Shimwell Timothy W*; Carpenter John M; Feroz Farhan; Grainge Keith J B; Hobson Michael P; Hurley Walker Natasha; Lasenby Anthony N; Olamaie Malak; Perrott Yvette C; Pooley Guy G; Rodriguez Gonzalvez Carmen; Rumsey Clare; Saunders Richard D E; Schammel Michel P; Scott Paul F; Titterington David J; Waldram Elizabeth M
来源:Monthly Notices of the Royal Astronomical Society, 2013, 433(3): 2036-2046.
DOI:10.1093/mnras/stt873

摘要

We present Combined Array for Research in Millimeter-wave Astronomy (CARMA) observations of a massive galaxy cluster discovered in the Arcminute Microkelvin Imager (AMI) blind Sunyaev-Zel'dovich (SZ) survey. Without knowledge of the cluster redshift a Bayesian analysis of the AMI, CARMA and joint AMI and CARMA uv-data is used to quantify the detection significance and parametrize both the physical and observational properties of the cluster whilst accounting for the statistics of primary cosmic microwave background anisotropies, receiver noise and radio sources. The joint analysis of the AMI and CARMA uv-data was performed with two parametric physical cluster models: the beta-model; and the model described in Olamaie et al. with the pressure profile fixed according to Arnaud et al. The cluster mass derived from these different models is comparable but our Bayesian evidences indicate a preference for the beta-profile which we, therefore, use throughout our analysis. From the CARMA data alone we obtain a formal Bayesian probability of detection ratio of 12.8:1 when assuming that a cluster exists within our search area; alternatively assuming that Jenkins et al. accurately predict the number of clusters as a function of mass and redshift, the formal Bayesian probability of detection is 0.29:1. From the Bayesian analysis of the AMI or AMI and CARMA data the probability of detection ratio exceeds 4.5 x 10(3):1. Performing a joint analysis of the AMI and CARMA data with a physical cluster model we derive the total mass internal to r(200) as M-T,M- 200 = 4.1 +/- 1.1 x 10(14) M-circle dot. Using a phenomenological beta-model to quantify the temperature decrement as a function of angular distance we find a central SZ temperature decrement of 170 +/- 24 mu K in the AMI and CARMA data. The SZ decrement in the CARMA data is weaker than expected and we speculate that this is a consequence of the cluster morphology. In a forthcoming study the pipeline that we have developed for the analyses of these data will be used to thoroughly assess the impact of cluster morphology on the SZ decrements that are observed with interferometers such as AMI and CARMA.

  • 出版日期2013-8
  • 单位CSIRO

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