Two simulated astronomical objects (a star cluster, and a young stellar object) were mock observed with the VLTI for different array configurations and instruments, and their images reconstructed and compared. The aim of the work is to infer when/if phase referencing with less telescopes is a better choice over closure phases with more telescopes. Three scenarios were put under scrutiny: Phase Referencing (PhR) with 2 telescopes vs Closure Phase (CPh) with 3 telescopes, PhR with 3 telescopes vs CPh with 4 telescopes, and PhR with 4 telescopes vs CPh with 6 telescopes. The number of nights is kept fixed for a given PhR vs CPh configuration. The UV -coverage was improved for the PhR case, by uniformly paving the (u, v) plane while keeping fixed the total number of sampled spatial frequencies. For the majority of the configurations, the results point to comparable performances of phase referencing and closure phases, when the UV-space is judiciously chosen.

Date Published: 24 July 2014
PDF: 10 pages
Proc. SPIE 9146, Optical and Infrared Interferometry IV, 91462M (24 July 2014); doi: 10.1117/12.2056545

Published in SPIE Proceedings Vol. 9146:
Optical and Infrared Interferometry IV
Jayadev K. Rajagopal; Michelle J. Creech-Eakman; Fabien Malbet, Editor(s)