read more
EDP Sciences Journals List
Home Document
Subscriber Authentication Point
Free access article

Issue A&A
Volume 502, Number 2, August I 2009
Page(s) 705 - 709
Section Astronomical instrumentation
DOI 10.1051/0004-6361/200811039
Published online 04 June 2009

A&A 502, 705-709 (2009)
DOI: 10.1051/0004-6361/200811039

Optimised data reduction for the AMBER/VLTI instrument

A. Chelli, O. Hernandez Utrera, and G. Duvert

Laboratoire d'Astrophysique de Grenoble and Mariotti Center, UMR 5571 Université Joseph Fourier/CNRS, BP 53, 38041 Grenoble Cedex 9, France
    e-mail: Alain.Chelli@obs.ujf-grenoble.fr

Received 25 September 2008 / Accepted 02 April 2009

Abstract
Context. The signal processing of multi-aperture monomode interferometers using multiaxial recombination, such as AMBER/VLTI, makes use of the modeling of the fringes in the image space called the “P2VM method”. This method was only validated on simulated data.
Aims. We aim to validate the P2VM method on-sky, and to use the knowledge acquired during more than three years of use of the instrument to provide improved data processing algorithms.
Methods. We compare the on-sky results of the P2VM algorithm with those provided by the standard, well known, and robust Fourier method.
Results. We first prove that the current implementation of the P2VM method used in the AMBER data reduction is biased for intermediate and low flux measurements. We determine the physical origin of these biases, then modify the data model accordingly, and introduce an improved noise model. We demonstrate that the P2VM method, together with the more realistic data and noise models, give results that are now in accordance with those provided by the Fourier method.


Key words: methods: data analysis -- instrumentation: interferometers



© ESO 2009


What is OpenURL?

The OpenURL standard is a protocol for transmission of metadata describing the resource that you wish to access. An OpenURL link contains article metadata and directs it to the OpenURL server of your choice. The OpenURL server can provide access to the resource and also offer complementary services (specific search engine, export of references...). The OpenURL link can be generated by different means.
  • If your librarian has set up your subscription with an OpenURL resolver, OpenURL links appear automatically on the abstract pages.
  • You can define your own OpenURL resolver with your EDPS Account. In this case your choice will be given priority over that of your library.
  • You can use an add-on for your browser (Firefox or I.E.) to display OpenURL links on a page (see http://www.openly.com/openurlref/). You should disable this module if you wish to use the OpenURL server that you or your library have defined.