The Atacama Cosmology Telescope (ACT): Beam Profiles and First SZ Cluster Maps
Abstract
The Atacama Cosmology Telescope (ACT) is currently observing the cosmic microwave background with arcminute resolution at 148 GHz, 218 GHz, and 277 GHz. In this paper, we present ACT's first results. Data have been analyzed using a maximum-likelihood map-making method which uses B-splines to model and remove the atmospheric signal. It has been used to make high-precision beam maps from which we determine the experiment's window functions. This beam information directly impacts all subsequent analyses of the data. We also used the method to map a sample of galaxy clusters via the Sunyaev-Zel'dovich (SZ) effect, and show five clusters previously detected with X-ray or SZ observations. We provide integrated Compton-y measurements for each cluster. Of particular interest is our detection of the z = 0.44 component of A3128 and our current non-detection of the low-redshift part, providing strong evidence that the further cluster is more massive as suggested by X-ray measurements. This is a compelling example of the redshift-independent mass selection of the SZ effect.
Keywords
Cite
@article{arxiv.0907.0461,
title = {The Atacama Cosmology Telescope (ACT): Beam Profiles and First SZ Cluster Maps},
author = {A. D. Hincks and V. Acquaviva and P. Ade and P. Aguirre and M. Amiri and J. W. Appel and L. F. Barrientos and E. S. Battistelli and J. R. Bond and B. Brown and B. Burger and J. Chervenak and S. Das and M. J. Devlin and S. Dicker and W. B. Doriese and J. Dunkley and R. Dünner and T. Essinger-Hileman and R. P. Fisher and J. W. Fowler and A. Hajian and M. Halpern and M. Hasselfield and C. Hernández-Monteagudo and G. C. Hilton and M. Hilton and R. Hlozek and K. Huffenberger and D. Hughes and J. P. Hughes and L. Infante and K. D. Irwin and R. Jimenez and J. B. Juin and M. Kaul and J. Klein and A. Kosowsky and J. M. Lau and M. Limon and Y. -T. Lin and R. H. Lupton and T. Marriage and D. Marsden and K. Martocci and P. Mauskopf and F. Menanteau and K. Moodley and H. Moseley and C. B. Netterfield and M. D. Niemack and M. R. Nolta and L. A. Page and L. Parker and B. Partridge and H. Quintana and B. Reid and N. Sehgal and J. Sievers and D. N. Spergel and S. T. Staggs and O. Stryzak and D. Swetz and E. Switzer and R. Thornton and H. Trac and C. Tucker and L. Verde and R. Warne and G. Wilson and E. Wollack and Y. Zhao},
journal= {arXiv preprint arXiv:0907.0461},
year = {2010}
}
Comments
16 pages, 10 figures. Accepted for publication in ApJS. See Marriage et al. (arXiv:1010.1065) and Menanteau et al. (arXiv:1006.5126) for additional cluster results