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arXiv · 2409.02847

Superfluid-tight cryogenic receiver with continuous sub-Kelvin cooling for EXCLAIM

Sumit Dahal·Peter A. R. Ade·Christopher J. Anderson·Alyssa Barlis·Emily M. Barrentine·Jeffrey W. Beeman·Nicholas Bellis·Alberto D. Bolatto·Victoria Braianova·Patrick C. Breysse·Berhanu T. Bulcha·Giuseppe Cataldo·Felipe A. Colazo·Lee-Roger Chevres-Fernandez·Chullhee Cho·Danny S. Chmaytelli·Jake A. Connors·Nicholas P. Costen·Paul W. Cursey·Negar Ehsan·Thomas M. Essinger-Hileman·Jason Glenn·Joseph E. Golec·James P. Hays-Wehle·Larry A. Hess·Amir E. Jahromi·Trevian Jenkins·Mark O. Kimball·Alan J. Kogut·Samuel H. Kramer·Nicole Leung·Luke N. Lowe·Philip D. Mauskopf·Jeffrey J. McMahon·Vilem Mikula·Mona Mirzaei·Samuel H. Moseley·Jonas W. Mugge-Durum·Jacob Nellis·Omid Noroozian·Kate Okun·Trevor Oxholm·Tatsat Parekh·Ue-Li Pen·Anthony R. Pullen·Maryam Rahmani·Mathias M. Ramirez·Cody Roberson·Samelys Rodriguez·Florian Roselli·Deepak Sapkota·Konrad Shire·Gage L. Siebert·Faizah Siddique·Adrian K. Sinclair·Rachel S. Somerville·Ryan Stephenson·Thomas R. Stevenson·Eric R. Switzer·Jared Termini·Peter T. Timbie·Justin Trenkamp·Carole E. Tucker·Elijah Visbal·Carolyn G. Volpert·Joseph Watson·Eric Weeks·Edward J. Wollack·Shengqi Yang·Aaron Yung
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Abstract

The EXperiment for Cryogenic Large-Aperture Intensity Mapping (EXCLAIM) is a balloon-borne telescope designed to survey star formation over cosmological time scales using intensity mapping in the 420 - 540 GHz frequency range. EXCLAIM uses a fully cryogenic telescope coupled to six on-chip spectrometers featuring kinetic inductance detectors (KIDs) to achieve high sensitivity, allowing for fast integration in dark atmospheric windows. The telescope receiver is cooled to $\approx$ 1.7 K by immersion in a superfluid helium bath and enclosed in a superfluid-tight shell with a meta-material anti-reflection coated silicon window. In addition to the optics and the spectrometer package, the receiver contains the magnetic shielding, the cryogenic segment of the spectrometer readout, and the sub-Kelvin cooling system. A three-stage continuous adiabatic demagnetization refrigerator (CADR) keeps the detectors at 100 mK while a $^4$He sorption cooler provides a 900 mK thermal intercept for mechanical suspensions and coaxial cables. We present the design of the EXCLAIM receiver and report on the flight-like testing of major receiver components, including the superfluid-tight receiver window and the sub-Kelvin coolers.

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Sumit Dahal, Peter A. R. Ade, Christopher J. Anderson, Alyssa Barlis, Emily M. Barrentine, Jeffrey W. Beeman, Nicholas Bellis, Alberto D. Bolatto, Victoria Braianova, Patrick C. Breysse, Berhanu T. Bulcha, Giuseppe Cataldo, Felipe A. Colazo, Lee-Roger Chevres-Fernandez, Chullhee Cho, Danny S. Chmaytelli, Jake A. Connors, Nicholas P. Costen, Paul W. Cursey, Negar Ehsan, Thomas M. Essinger-Hileman, Jason Glenn, Joseph E. Golec, James P. Hays-Wehle, Larry A. Hess, Amir E. Jahromi, Trevian Jenkins, Mark O. Kimball, Alan J. Kogut, Samuel H. Kramer, Nicole Leung, Luke N. Lowe, Philip D. Mauskopf, Jeffrey J. McMahon, Vilem Mikula, Mona Mirzaei, Samuel H. Moseley, Jonas W. Mugge-Durum, Jacob Nellis, Omid Noroozian, Kate Okun, Trevor Oxholm, Tatsat Parekh, Ue-Li Pen, Anthony R. Pullen, Maryam Rahmani, Mathias M. Ramirez, Cody Roberson, Samelys Rodriguez, Florian Roselli, Deepak Sapkota, Konrad Shire, Gage L. Siebert, Faizah Siddique, Adrian K. Sinclair, Rachel S. Somerville, Ryan Stephenson, Thomas R. Stevenson, Eric R. Switzer, Jared Termini, Peter T. Timbie, Justin Trenkamp, Carole E. Tucker, Elijah Visbal, Carolyn G. Volpert, Joseph Watson, Eric Weeks, Edward J. Wollack, Shengqi Yang, Aaron Yung. 2024-09-04. Superfluid-tight cryogenic receiver with continuous sub-Kelvin cooling for EXCLAIM. https://doi.org/10.1117/12.3018577

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