Paper
24 July 2014 Modeling chromatic instrumental effects for a better model fitting of optical interferometric data
Author Affiliations +
Abstract
Current interferometers often collect data simultaneously in many spectral channels by using dispersed fringes. Such polychromatic data provide powerful insights in various physical properties, where the observed objects show particular spectral features. Furthermore, one can measure spectral differential visibilities that do not directly depend on any calibration by a reference star. But such observations may be sensitive to instrumental artifacts that must be taken into account in order to fully exploit the polychromatic information of interferometric data. As a specimen, we consider here an observation of P Cygni with the VEGA visible combiner on CHARA interferometer. Indeed, although P Cygni is particularly well modeled by the radiative transfer code CMFGEN, we observe questionable discrepancies between expected and actual interferometric data. The problem is to determine their origin and disentangle possible instrumental effects from the astrophysical information. By using an expanded model fitting, which includes several instrumental features, we show that the differential visibilities are well explained by instrumental effects that could be otherwise attributed to the object. Although this approach leads to more reliable results, it assumes a fit specific to a particular instrument, and makes it more difficult to develop a generic model fitting independent of any instrument.
© (2014) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
M. Tallon, I. Tallon-Bosc, O. Chesneau, and L. Dessart "Modeling chromatic instrumental effects for a better model fitting of optical interferometric data", Proc. SPIE 9146, Optical and Infrared Interferometry IV, 91460N (24 July 2014); https://doi.org/10.1117/12.2057354
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Data modeling

Visibility

Instrument modeling

Stars

Interferometry

Atmospheric modeling

Sensors

RELATED CONTENT

Simulating interferometric data of binary systems
Proceedings of SPIE (July 24 2014)
StarLight mission: a formation-flying stellar interferometer
Proceedings of SPIE (February 26 2003)
Recent progress at the CHARA interferometric array
Proceedings of SPIE (June 27 2006)
Observation planning tools for the ESO VLT interferometer
Proceedings of SPIE (September 16 2004)
Estimation of confusion in SIM targets with a detailed focal...
Proceedings of SPIE (September 19 2007)
Interferometric measurements of stellar intensity profiles
Proceedings of SPIE (February 21 2003)

Back to Top