First Very Long Baseline Interferometry Fringe Detection at 690 GHz
Artikel i vetenskaplig tidskrift, 2026

We report the first very long baseline interferometry (VLBI) experiment conducted in the 690 GHz atmospheric window. On 2024 November 21, observations with the Atacama Large Millimeter/submillimeter Array, the Atacama Pathfinder EXperiment (APEX), and the James Clerk Maxwell Telescope (JCMT) were carried out using ALMA's newly developed Band 9 phasing capability. Fringes were detected on the ALMA-APEX baseline during a scan of the quasar J0423-0120, with a signal-to-noise ratio of similar to 12 and useful fringe recovery over solution intervals of order tens of seconds, representing the highest-frequency ground-based VLBI fringe detection reported to date. No fringes were found on the ALMA-JCMT baseline, despite excellent weather conditions, consistent with sensitivity predictions and supporting baseline performance models. The ALMA Phasing System maintained stable phasing at Band 9 for similar to 1-2 minutes before gradually degrading, indicating limitations under these observing conditions. Our analysis shows that, under excellent weather conditions, 690 GHz VLBI can still support fringe recovery over short solution intervals, despite rapid atmospheric phase fluctuations at these frequencies. This work validated key elements of near-terahertz VLBI operation and establishes a technical foundation for routine observations in the 690 GHz atmospheric window.

Författare

Ming-Tang Chen

Academia Sinica

Geoffrey B. Crew

Massachusetts Institute of Technology (MIT)

Dan Bintley

East Asian Observatory

Alan Roy

Max-Planck-Gesellschaft

Keiichi Asada

Academia Sinica

Johnson Han

Academia Sinica

Kuan-Yu Liu

East Asian Observatory

Chin-Shin Chang

Atacama Large Millimeter-submillimeter Array (ALMA)

Université de Genève

Andrea McCloskey

East Asian Observatory

Yiqing Song

Atacama Large Millimeter-submillimeter Array (ALMA)

Vincent Fish

Massachusetts Institute of Technology (MIT)

Michael Lindqvist

Chalmers, Rymd-, geo- och miljövetenskap, Onsala rymdobservatorium

Satoki Matsushita

Academia Sinica

Lynn D. Matthews

Massachusetts Institute of Technology (MIT)

Hugo Messias

Atacama Large Millimeter-submillimeter Array (ALMA)

Jan F. Wagner

Max-Planck-Gesellschaft

Ue-Li Pen

Academia Sinica

Derek Kubo

Academia Sinica

Teddy Huang

Academia Sinica

Philippe Raffin

Academia Sinica

Chih-Wei L. Huang

Academia Sinica

Pierre Martin-Cocher

Academia Sinica

Geoffrey C. Bower

Academia Sinica

East Asian Observatory

Patrick Koch

Academia Sinica

Lisa Kewley

Harvard-Smithsonian Center for Astrophysics

Timothy Norton

Harvard-Smithsonian Center for Astrophysics

Nimesh Patel

Harvard-Smithsonian Center for Astrophysics

Paul T. P. Ho

East Asian Observatory

Per Friberg

East Asian Observatory

Izumi Mizuno

East Asian Observatory

Akil Marshall

East Asian Observatory

Andrey M. Baryshev

Rijksuniversiteit Groningen

Heino Falcke

Radboud Universiteit

Thomas Greve

Danmarks Tekniske Universitet (DTU)

Jacques Lepine

Universidade de Sao Paulo (USP)

Manuel Fernandez Lopez

Universidad Nacional de La Plata

Silvina Cichowolski

CONICET–UBA

Carlos Valotto

Instituto de Astronomía Teórica y Experimental (IATE)

Universidad Nacional de Córdoba

Ciriaco Goddi

Istituto Nazionale di Fisica Nucleare

Istituto nazionale di astrofisica (INAF)

Universita degli Studi di Cagliari

Guillermo Gimenez de Castro

Mackenzie Presbyterian University

CONICET–UBA

Fatima Salete Correra

Universidade de Sao Paulo (USP)

Marianne Vestergaard

Köpenhamns universitet

Jes Kristian Jorgensen

Köpenhamns universitet

Martin E. Pessah

Niels Bohr Institute

Roman Gold

Universität Heidelberg

Syddansk Universitet

Publications of the Astronomical Society of the Pacific

0004-6280 (ISSN) 1538-3873 (eISSN)

Vol. 138 8 084104

ERGODIC: Kombinerade person- och godstransporter i förortstrafik

Europeiska kommissionen (EU) (F-ENUAC-2022-0003), 2023-10-01 -- 2026-09-30.

VINNOVA (ERGODIC), 2023-10-01 -- 2026-09-30.

Europeiska kommissionen (EU) (F-DUT-2022-0078), 2023-10-01 -- 2026-09-30.

Ämneskategorier (SSIF 2025)

Atom- och molekylfysik och optik

Fusion, plasma och rymdfysik

Astronomi, astrofysik och kosmologi

DOI

10.1088/1538-3873/ae92b6

Mer information

Senast uppdaterat

2026-09-10