Other
Assorted and legacy projects — some still ongoing, some I've stepped back from.
SPT
The South Pole Telescope is a 10 m microwave telescope at the geographic South Pole. SPT studies the Cosmic Microwave Background — the leftover light from the Big Bang — with sub-arcminute angular resolution. I joined the collaboration as a graduate student at U Chicago and spent the austral winter of 2008 on-site as one of two winterovers. SPT-SZ, SPTpol, and SPT-3G have each in turn yielded a long stream of results; I've since moved on.
ARO — pulsar scintillometry
Canada's Algonquin Radio Observatory houses a 46 m dish where the technique of Very-Long-Baseline Interferometry (VLBI) was invented. We built new low-frequency feeds and digital backends there, and the lab still makes regular trips up to test new hardware. We also used the dish for pulsar scintillometry — treating interstellar plasma lensing as a natural 10-billion-kilometre interferometer to resolve structure inside pulsar emission regions — though I've since phased off that line of work. ARO remains an active test site for us.
HIRAX
The Hydrogen Intensity and Real-time Analysis eXperiment is a southern-hemisphere 21cm intensity-mapping array in South Africa, complementary in many ways to CHIME. The 256-element system overview (Crichton et al., 2022) describes the design. HIRAX is ongoing and under construction; I'm a co-I, with the project driven primarily by collaborators in South Africa and elsewhere.