The Advanced ACTPol upgrade on the Atacama Cosmology Telescope aims to improve the measurement of the cosmic microwave background anisotropies and polarization, using four new dichroic detector arrays fabricated on 150-mm silicon wafers. These bolometric cameras use AlMn transition-edge sensors, coupled to feedhorns with orthomode transducers for polarization sensitivity. The first deployed camera is sensitive to both 150 GHz and 230 GHz. Here we present the lab characterization of the thermal parameters and optical efficiencies for the two newest fielded arrays, each sensitive to both 90 GHz and 150 GHz. We provide assessments of the parameter uniformity across each array with evaluation of systematic uncertainties. Lastly, we show the arrays' initial performance in the field.
@article{arxiv.1711.04841,
title = {Characterization of the Mid-Frequency Arrays for Advanced ACTPol},
author = {Steve K. Choi and Jason Austermann and James A. Beall and Kevin T. Crowley and Rahul Datta and Shannon M. Duff and Patricio A. Gallardo and Shuay-Pwu P. Ho and Johannes Hubmayr and Brian J. Koopman and Yaqiong Li and Federico Nati and Michael D. Niemack and Lyman A. Page and Maria Salatino and Sara M. Simon and Suzanne T. Staggs and Jason Stevens and Joel Ullom and Edward J. Wollack},
journal= {arXiv preprint arXiv:1711.04841},
year = {2018}
}
Comments
Version accepted for publication by Journal of Low Temperature Physics