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arXiv · 2301.04543

A Characterization of the ALMA Phasing System at 345 GHz

G. B. Crew·C. Goddi·L. D. Matthews·H. Rottmann·A. Saez·I. Marti-Vidal
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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).

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G. B. Crew, C. Goddi, L. D. Matthews, H. Rottmann, A. Saez, I. Marti-Vidal. 2023-01-11. A Characterization of the ALMA Phasing System at 345 GHz. https://doi.org/10.1088/1538-3873%2Facb348

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