The Simons Observatory Large Aperture Telescope Receiver
Ningfeng Zhu, Tanay Bhandarkar, Gabriele Coppi, Anna M. Kofman, John L. Orlowski-Scherer, Zhilei Xu, Shunsuke Adachi, Peter Ade, Simone Aiola, Jason Austermann, Andrew O. Bazarko, James A. Beall, Sanah Bhimani, J. Richard Bond, Grace E. Chesmore, Steve K. Choi, Jake Connors, Nicholas F. Cothard, Mark Devlin, Simon Dicker, Bradley Dober, Cody J. Duell, Shannon M. Duff, Rolando Dünner, Giulio Fabbian, Nicholas Galitzki, Patricio A. Gallardo, Joseph E. Golec, Saianeesh K. Haridas, Kathleen Harrington, Erin Healy, Shuay-Pwu Patty Ho, Zachary B. Huber, Johannes Hubmayr, Jeffrey Iuliano, Bradley R. Johnson, Brian Keating, Kenji Kiuchi, Brian J. Koopman, Jack Lashner, Adrian T. Lee, Yaqiong Li, Michele Limon, Michael Link, Tammy J Lucas, Heather McCarrick, Jenna Moore, Federico Nati, Laura B. Newburgh, Michael D. Niemack, Elena Pierpaoli, Michael J. Randall, Karen Perez Sarmiento, Lauren J. Saunders, Joseph Seibert, Carlos Sierra, Rita Sonka, Jacob Spisak, Shreya Sutariya, Osamu Tajima, Grant P. Teply, Robert J. Thornton, Tran Tsan, Carole Tucker, Joel Ullom, Eve M. Vavagiakis, Michael R. Vissers, Samantha Walker, Benjamin Westbrook, Edward J. Wollack, Mario Zannoni
Abstract
Abstract The Simons Observatory is a ground-based cosmic microwave background experiment that consists of three 0.4 m small-aperture telescopes and one 6 m Large Aperture Telescope, located at an elevation of 5300 m on Cerro Toco in Chile. The Simons Observatory Large Aperture Telescope Receiver (LATR) is the cryogenic camera that will be coupled to the Large Aperture Telescope. The resulting instrument will produce arcminute-resolution millimeter-wave maps of half the sky with unprecedented precision. The LATR is the largest cryogenic millimeter-wave camera built to date, with a diameter of 2.4 m and a length of 2.6 m. The coldest stage of the camera is cooled to 100 mK, the operating temperature of the bolometric detectors with bands centered around 27, 39, 93, 145, 225, and 280 GHz. Ultimately, the LATR will accommodate 13 40 cm diameter optics tubes, each with three detector wafers and a total of 62,000 detectors. The LATR design must simultaneously maintain the optical alignment of the system, control stray light, provide cryogenic isolation, limit thermal gradients, and minimize the time to cool the system from room temperature to 100 mK. The interplay between these competing factors poses unique challenges. We discuss the trade studies involved with the design, the final optimization, the construction, and ultimate performance of the system.