@inproceedings{f902fe1d097b45598c88524c65b66486,
title = "A VLBI receiving system for the South Pole Telescope",
abstract = "The Event Horizon Telescope (EHT) is a very-long-baseline interferometry (VLBI) experiment that aims to observe supermassive black holes with an angular resolution that is comparable to the event horizon scale. The South Pole occupies an important position in the array, greatly increasing its north-south extent and therefore its resolution. The South Pole Telescope (SPT) is a 10-meter diameter, millimeter-wavelength telescope equipped for bolometric observations of the cosmic microwave background. To enable VLBI observations with the SPT we have constructed a coherent signal chain suitable for the South Pole environment. The dual-frequency receiver incorporates state-of-the-art SIS mixers and is installed in the SPT receiver cabin. The VLBI signal chain also includes a recording system and reference frequency generator tied to a hydrogen maser. Here we describe the SPT VLBI system design in detail and present both the lab measurements and on-sky results.",
keywords = "EHT, SIS receiver, SPT, VLBI, submillimeter",
author = "Junhan Kim and Marrone, {Daniel P.} and Christopher Beaudoin and Carlstrom, {John E.} and Doeleman, {Shepherd S.} and Folkers, {Thomas W.} and David Forbes and Greer, {Christopher H.} and Lauria, {Eugene F.} and Massingill, {Kyle D.} and Evan Mayer and Nguyen, {Chi H.} and George Reiland and Jason Soohoo and Stark, {Antony A.} and Laura Vertatschitsch and Jonathan Weintroub and Andr{\'e} Young",
note = "Funding Information: J.K. and D.P.M. acknowledge support from NSF grants AST-1207752 and AST-1440254. The South Pole Telescope program is supported by the National Science Foundation through grant PLR-1248097. Partial support is also provided by the NSF Physics Frontier Center grant PHY-0114422 to the Kavli Institute of Cosmological Physics at the University of Chicago, the Kavli Foundation, and the Gordon and Betty Moore Foundation through Grant GBMF#947 to the University of Chicago. We thank Chris Kendall and Dave Pernic for their assistance at the South Pole. We acknowledge essential support for this system that is provided through the loan of several key components. The maser and quartz crystal are on loan from the Academia Sinica Institute of Astronomy and Astrophysics. The National Radio Astronomy Observatory has loaned the band 6 feed horn, which does not meet ALMA specifications at non-EHT frequencies. The Smithsonian Astrophysical Observatory has loaned cryogenic IF amplifiers that are used in the band 7 receiving system. Publisher Copyright: {\textcopyright} 2018 SPIE.; Millimeter, Submillimeter, and Far-Infrared Detectors and Instrumentation for Astronomy IX 2018 ; Conference date: 12-06-2018 Through 15-06-2018",
year = "2018",
doi = "10.1117/12.2301005",
language = "English (US)",
isbn = "9781510619692",
series = "Proceedings of SPIE - The International Society for Optical Engineering",
publisher = "SPIE",
editor = "Jonas Zmuidzinas and Jian-Rong Gao",
booktitle = "Millimeter, Submillimeter, and Far-Infrared Detectors and Instrumentation for Astronomy IX",
}