Denis Defrère - Professor of Astronomy

Belgian VLTI Expertise Centre

As part of the OPTICON H2020 (2016-2020) project and OPTICON/RadioNet Pilot (ORP) program (2021-2025), a network of VLTI Expertise Centres has been established in Europe. These centres are the backbone of dissemination activities to new VLTI users, by organising observing preparation and data reduction schools, by co-organising with ESO the VLTI community days, and being the end-points of the Fizeau staff exchange programme. The centres follow at a smaller scale the successful experience of the ALMA Regional Centres. They are the visible first contact point for astronomers interested in using VLTI.

The Belgian centre appears as an evolution of a long-standing expertise in optical interferometry that had its beginnings in the early definition of the VLTI and the astrophysical exploitation of its instruments over the generations (i.e., VINCI, AMBER, PIONIER, GRAVITY, MATISSE). The Belgian centre is also part of the European Interferometry Initiative networking activity since FP7.

The Very Large Telescope Interferometer is a globally unparalleled infrastructure, which provides European astronomers with access to observations at milliarcsecond angular resolution, at low, intermediate and high spectral resolution, at near-infrared and infrared wavelengths.

The current VLTI instruments are:

PIONIER – 4-way beam combiner in the H-band, on the VLTI visitor focus.
GRAVITY – 4-way beam combiner in the K-band, with spectroscopic, fringe tracking and astrometric capabilities.
MATISSE – 4-way beam combiner in the L, M and N infrared bands.

The aims of the Belgian VLTI Expertise Centre are:

Integrate and disseminate knowledge being developed across the community, ensuring long-term sustainability;
Support observing proposal and observation preparation, data reduction, and imaging;
Co-organize (with ESO) VLTI community days and the EII meetings, bringing together 15 countries, and ESO and ESA, as well as the radio/mm interferometry community;
Exchange experience and coordinate with the radio/mm interferometry community, when possible in conjunction with ALMA centres of expertise.

The core team is composed of the following scientists:

Coordination: D. Defrère ( denis.defrere@kuleuven.be )
Lead scientists: J. Kluska ( jacques.kluska@kuleuven.be ) and O. Absil ( olivier.absil@uliege.be )