The Wide-Field Infrared Transient Explorer
WINTER is a seeing-limited near-infrared instrument on a dedicated 1-meter robotic telescope. WINTER is designed to discover kilonovae, the explosions from neutron stars merging with other neutron stars or black holes. In Frostig et al. 2022 we predict WINTER will discover up to five new kilonovae during the fourth gravitational-wave observing run. Futhermore, with its near-infrared all-sky surveys, WINTER will study supernovae, exoplanets, tidal disruption events, and more.
InGaAs detectors for infrared astronomy
At the heart of WINTER is the development of InGaAs detectors as a cheaper alternative for near-infrared astronomy. WINTER combines six commercial, wide-format InGaAs detectors to cover one square degree on the sky between 0.9 and 1.7 microns. InGaAs detectors are a cost-effective way to build infrared instruments without cryogenic cooling and still achieve sky-background limited performance. I led the detector operations and testing for WINTER.
In order to cover over a square degree on the sky with six sensors, WINTER's novel fly's-eye design splits up the optical path into six channels. This requires custom optics and mounting hardware. I contributed to the optical design and intrument alignment, which you can learn more about in Lourie et al 2020.
We read out each WINTER sensor at 7 frames per second, with a planned upgrade to 30 frames per second. By saving many data points during each image (non-destructive read) we can improve the image quality and reduce read noise. Fast reads require custom electronics, firmware, and software. I tested our custom electronics, wrote all the firmware to control the electronics and detectors with FPGAs, and wrote custom readout software which includes GPUs for real-time data processing. You can learn more about the readout in Frostig et al. 2022.
Dedicated 1-meter robotic telescope
WINTER lives on a dedicated 1-meter robotic telescope at Palomar Observatory. The project runs autonomously each night without supervision. I wrote the scheduling software such that each night WINTER decides which images to take based on historic data, scheduling constraints, and balancing scientific priorities.