A Characterization of the ALMA Phasing System at 345 GHz

Abstract

The development of the Atacama Large Millimeter/submillimeter Array (ALMA) phasing system (APS) has allowed ALMA to function as an extraordinarily sensitive station for very long baseline interferometry (VLBI) at frequencies of up to 230 GHz (~1.3 mm). Efforts are now underway to extend use of the APS to 345 GHz (~0.87 mm). Here we report a characterization of APS performance at 345 GHz based on a series of tests carried out between 2015-2021, including a successful global VLBI test campaign conducted in 2018 October in collaboration with the Event Horizon Telescope (EHT).

22 pages, 11 figures, 7 tables, accepted for publication in PASP

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Cited by in corpus (8)

• Key Science Goals for the Next-Generation Event Horizon Telescope
• The Black Hole Explorer: Motivation and Vision
• Reference Array and Design Consideration for the next-generation Event Horizon Telescope
• Broadband Multi-wavelength Properties of M87 during the 2018 EHT Campaign including a Very High Energy Flaring Episode
• First Very Long Baseline Interferometry Detections at 870μm
• First polarization study of the M87 jet and active galactic nuclei at submillimeter wavelengths with ALMA
• First Very Long Baseline Interferometry Fringe Detection at 690GHz
• Full-polarization millimeter wavelength variability of Sagittarius A* during the 2018 EHT campaign