A VLBI Receiving System for the South Pole Telescope

The Event Horizon Telescope (EHT) is a global millimeter very-long-baseline interferometry (VLBI) array designed to image supermassive black holes at event-horizon scales. The collaboration released the first image of the black hole in M87 in 2019 and the first image of Sagittarius A*, the black hole at the center of the Milky Way, in 2022 [EHT Collaboration et al. 2019, 2022]. This project reflects Junhan's earlier work and remains an important foundation for the lab's broader interests in radio instrumentation.

A major component of this work was the development of a dedicated VLBI receiving system for the South Pole Telescope  (SPT), a 10-meter millimeter telescope at the South Pole that significantly extends the EHT's north–south baselines. To enable VLBI observations with the SPT, Junhan developed the dual-frequency receiver and coherent signal chain, carrying the system from design and integration to lab characterization, on-sky testing, and software development.

Related Publications

• First Sagittarius A* Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole in the Center of the Milky Way [ADS] [arXiv]

The Event Horizon Telescope Collaboration et al., including Kim, J., 2022, ApJL, 930, L12

• Event Horizon Telescope Observations of the Jet Launching and Collimation in Centaurus A [ADS] [arXiv]

Janssen, M. et al., including Kim, J., 2021, Nature Astronomy, 5, 1017 

• First M87 Event Horizon Telescope Results. II. Array and Instrumentation [ADS] [arXiv]

The Event Horizon Telescope Collaboration et al., including Kim, J., 2019, ApJL, 875, L2

• A VLBI receiving system for the South Pole Telescope [ADS] [arXiv]

Kim, J., Marrone, D. P., et al., 2018, Proceedings of SPIE, 10708, 107082S

• The 1.4 mm core of Centaurus A: First VLBI results with the South Pole Telescope [ADS] [arXiv]

Kim, J., Marrone, D. P., et al., 2018, ApJ, 861, 129

• Tilted beam measurement of VLBI receiver for the South Pole Telescope [ADS] [arXiv]

Kim, J. & Marrone, D. P., 2018, Proceedings of the 29th International Symposium on Space Terahertz Technology, 159-163