SuperBIT Superpressure Flight Instrument Overview and Performance: Near diffraction-limited Astronomical Imaging from the Stratosphere

TL;DR

SuperBIT is a balloon-borne telescope that achieved near-diffraction limited imaging in the stratosphere, demonstrating high stability and performance for astronomical observations over a 45-night flight, serving as a pathfinder for future larger telescopes.

Contribution

This paper provides the first comprehensive overview and performance assessment of SuperBIT, a near-ultraviolet to near-infrared balloon telescope, showcasing its capabilities and technical achievements.

Findings

Achieved telescope pointing stability of 0.34 arcseconds.

Maintained focal plane image stability of 0.055 arcseconds.

Attained a PSF FWHM of ~0.35 arcseconds in all science bands.

Abstract

SuperBIT was a 0.5-meter near-ultraviolet to near-infrared wide-field telescope that launched on a NASA superpressure balloon into the stratosphere from New Zealand for a 45-night flight. SuperBIT acquired multi-band images of galaxy clusters to study the properties of dark matter using weak gravitational lensing. We provide an overview of the instrument and its various subsystems. We then present the instrument performance from the flight, including the telescope and image stabilization system, the optical system, the power system, and the thermal system. SuperBIT successfully met the instrument's technical requirements, achieving a telescope pointing stability of 0.34 +/- 0.10 arcseconds, a focal plane image stability of 0.055 +/- 0.027 arcseconds, and a PSF FWHM of ~ 0.35 arcseconds over 5-minute exposures throughout the 45-night flight. The telescope achieved a near-diffraction limited point-spread function in all three science bands (u, b, and g). SuperBIT served as a pathfinder to the GigaBIT observatory, which will be a 1.34-meter near-ultraviolet to near-infrared balloon-borne telescope.