Characterization, deployment, and in-flight performance of the BLAST-TNG cryogenic receiver

TL;DR

This paper details the design, deployment, and in-flight performance of the BLAST-TNG cryogenic receiver, a submillimeter polarimeter with advanced MKID detector arrays used for astrophysical observations during a 24-day Antarctic flight.

Contribution

It introduces the first comprehensive overview of BLAST-TNG's cryogenic receiver system, including detector arrays, readout electronics, and in-flight performance analysis.

Findings

Successful deployment of 918, 469, and 272 MKID pixels in the detector arrays.

Effective cooling and stabilization of detectors at sub 300mK temperatures.

In-flight performance data demonstrating system reliability and sensitivity.

Abstract

The Next Generation Balloon-borne Large Aperture Submillimeter Telescope (BLAST-TNG) is a submillimeter polarimeter designed to map interstellar dust and galactic foregrounds at 250, 350, and 500 microns during a 24-day Antarctic flight. The BLAST-TNG detector arrays are comprised of 918, 469, and 272 MKID pixels, respectively. The pixels are formed from two orthogonally oriented, crossed, linear-polarization sensitive MKID antennae. The arrays are cooled to sub 300mK temperatures and stabilized via a closed cycle $^3$He sorption fridge in combination with a $^4$He vacuum pot. The detectors are read out through a combination of the second-generation Reconfigurable Open Architecture Computing Hardware (ROACH2) and custom RF electronics designed for BLAST-TNG. The firmware and software designed to readout and characterize these detectors was built from scratch by the BLAST team around these detectors, and has been adapted for use by other MKID instruments such as TolTEC and OLIMPO. We present an overview of these systems as well as in-depth methodology of the ground-based characterization and the measured in-flight performance.