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Title: Performance of the upgraded VERITAS Stellar Intensity Interferometer (VSII)
The VERITAS Imaging Air Cherenkov Telescope array (IACT) was augmented in 2019 with high-speed focal plane electronics to create a new Stellar Intensity Interferometry (SII) observational capability (VERITAS-SII, or VSII). VSII operates during bright moon periods, providing high angular resolution observations ( < 1 mas) in the B photometric band using idle telescope time. VSII has already demonstrated the ability to measure the diameters of two B stars at 416 nm (Bet CMa and Eps Ori) with < 5% accuracy using relatively short (5 hours) exposures.1 The VSII instrumentation was recently improved to increase instrumental sensitivity and observational efficiency. This paper describes the upgraded VSII instrumentation and documents the ongoing improvements in VSII sensitivity. The report describes VSII’s progress in extending SII measurements to dimmer magnitude stars and improving the VSII angular diameter measurement resolution to better than 1%.  more » « less
Award ID(s):
2117641 2111531
NSF-PAR ID:
10352254
Author(s) / Creator(s):
;
Editor(s):
Mérand, Antoine; Sallum, Stephanie; Sanchez-Bermudez, Joel
Date Published:
Journal Name:
SPIE Astronomical Telescopes + Instrumentation, 2022, Montréal, Québec, Canada : Optical and Infrared Interferometry and Imaging VIII
Volume:
12183
Issue:
121830D
Page Range / eLocation ID:
12
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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