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arXiv · 1808.08489

Preflight Characterization of the BLAST-TNG Receiver and Detector Arrays

Abstract

The Next Generation Balloon-borne Large Aperture Submillimeter Telescope (BLAST-TNG) is a submillimeter mapping experiment planned for a 28 day long-duration balloon (LDB) flight from McMurdo Station, Antarctica during the 2018-2019 season. BLAST-TNG will detect submillimeter polarized interstellar dust emission, tracing magnetic fields in galactic molecular clouds. BLAST-TNG will be the first polarimeter with the sensitivity and resolution to probe the $\sim$0.1 parsec-scale features that are critical to understanding the origin of structures in the interstellar medium. BLAST-TNG features three detector arrays operating at wavelengths of 250, 350, and 500 $\mu$m (1200, 857, and 600 GHz) comprised of 918, 469, and 272 dual-polarization pixels, respectively. Each pixel is made up of two crossed microwave kinetic inductance detectors (MKIDs). These arrays are cooled to 275 mK in a cryogenic receiver. Each MKID has a different resonant frequency, allowing hundreds of resonators to be read out on a single transmission line. This inherent ability to be frequency-domain multiplexed simplifies the cryogenic readout hardware, but requires careful optical testing to map out the physical location of each resonator on the focal plane. Receiver-level optical testing was carried out using both a cryogenic source mounted to a movable xy-stage with a shutter, and a beam-filling, heated blackbody source able to provide a 10-50 $^\circ$C temperature chop. The focal plane array noise properties, responsivity, polarization efficiency, instrumental polarization were measured. We present the preflight characterization of the BLAST-TNG cryogenic system and array-level optical testing of the MKID detector arrays in the flight receiver.

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Nathan P. Lourie, Peter A. R. Ade, Francisco E. Angile, Peter C. Ashton, Jason E. Austermann, Mark J. Devlin, Bradley Dober, Nicholas Galitzki, Jiansong Gao, Sam Gordon, Christopher E. Groppi, Jeffrey Klein, Gene C. Hilton, Johannes Hubmayr, Dale Li, Ian Lowe, Hamdi Mani, Philip Mauskopf, Christopher M. McKenney, Federico Nati, Giles Novak, Enzo Pascale, Giampaolo Pisano, Adrian Sinclair, Juan D. Soler, Carole Tucker, Joel Ullom, Michael Vissers, Paul A. Williams. 2018-08-26. Preflight Characterization of the BLAST-TNG Receiver and Detector Arrays. https://doi.org/10.1117/12.2314396

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