Taurus CMB Experiment

Science Goals

Taurus is a balloon-borne cosmic microwave background (CMB) experiment optimized to map the \(E\)-mode polarization and Galactic foregrounds at the largest angular scales (\(\ell <\) 30) and improve measurements of the optical depth to reionization (\(\tau\)). This will pave the way for improved measurements of the sum of neutrino masses in combination with high-resolution CMB data as well as test the \(\Lambda\)CDM model on large angular scales while also providing high-frequency maps of polarized dust foregrounds to the CMB community. These measurements take advantage of the low-loading environment found in the stratosphere and are enabled by a mid-latitude launch location (Wanaka, NZ), which provides access to 70\% of the sky from NASA’s super-pressure balloon platform. Taurus will employ more than 10,000 100~mK transition edge sensor bolometers distributed across two low-frequency (150, 220 GHz) and one high-frequency (280, 350 GHz) dichroic receivers. The instrument and scan strategy are designed for rigorous control of instrumental systematics, enabling high-fidelity linear polarization measurements on the largest angular scales. The liquid helium cryostat housing the detectors and optics is supported by a lightweight gondola. The payload is designed to meet the challenges in mass, power, and thermal control posed by the super-pressure platform. Here we describe a general overview of Taurus, with an emphasis on the instrument design.

Publications

May, J. L., Adler, A. E., Austermann, J. E., Benton, S. J., Bihary, R., Durkin, M., … & Vissers, M. R. (2024, August). Instrument overview of Taurus: a balloon-borne CMB and dust polarization experiment. In Ground-based and Airborne Telescopes X (Vol. 13094, pp. 1296-1310). SPIE.
arXiv

Tartakovsky, S., Adler, A. E., Austermann, J. E., Benton, S. J., Bihary, R., Durkin, M., … & Vissers, M. R. (2024, August). Thermal architecture for a cryogenic super-pressure balloon payload: design and development of the Taurus flight cryostat. In Ground-based and Airborne Telescopes X (Vol. 13094, pp. 1693-1701). SPIE.
arXiv

Adler, A. E., Austermann, J. E., Benton, S. J., Duff, S. M., Filippini, J. P., Fraisse, A. A., … & Vissers, M. R. (2024). Modeling optical systematics for the Taurus CMB experiment. arXiv preprint arXiv:2406.11992.
arXiv