Measuring Reionization, Neutrino Mass, and Cosmic Inflation with BFORE

TL;DR

BFORE is a balloon mission designed to measure the cosmic microwave background across large sky areas, aiming to improve understanding of reionization, neutrino mass, and cosmic inflation through advanced multi-frequency observations.

Contribution

It introduces a novel balloon platform for CMB measurements that enhances large-scale data collection and foreground separation, utilizing advanced TES multichroic detectors and microwave readout technologies.

Findings

Improved measurement of optical depth to reionization tau.

Potential detection of primordial gravitational wave B-mode signals at r~0.01.

Enhanced foreground separation and galaxy cluster velocity measurements.

Abstract

BFORE is a NASA high-altitude ultra-long-duration balloon mission proposed to measure the cosmic microwave background (CMB) across half the sky during a 28-day mid-latitude flight launched from Wanaka, New Zealand. With the unique access to large angular scales and high frequencies provided by the balloon platform, BFORE will significantly improve measurements of the optical depth to reionization tau, breaking parameter degeneracies needed for a measurement of neutrino mass with the CMB. The large angular scale data will enable BFORE to hunt for the large-scale gravitational wave B-mode signal, as well as the degree-scale signal, each at the r~0.01 level. The balloon platform allows BFORE to map Galactic dust foregrounds at frequencies where they dominate, in order to robustly separate them from CMB signals measured by BFORE, in addition to complementing data from ground-based telescopes. The combination of frequencies will also lead to velocity measurements for thousands of galaxy clusters, as well as probing how star-forming galaxies populate dark matter halos. The mission will be the first near-space use of TES multichroic detectors (150/217 GHz and 280/353 GHz bands) using highly-multiplexed mSQUID microwave readout, raising the technical readiness level of both technologies.