An overview of the mid-infrared spectro-interferometer MATISSE: science, concept, and current status

TL;DR

MATISSE is a new mid-infrared interferometric instrument for VLTI that enables advanced imaging and spectral analysis of astronomical objects, significantly expanding observational capabilities in the 2.8 to 13 micrometer range.

Contribution

This paper introduces the design, capabilities, and current status of MATISSE, a second-generation mid-infrared spectro-interferometer for the VLTI, highlighting its novel spectral and imaging functionalities.

Findings

Enables mid-infrared imaging with up to four telescopes.

Offers spectral resolution from R ~ 30 to R ~ 5000.

Expands wavelength coverage to 2.8-13 micrometers.

Abstract

MATISSE is the second-generation mid-infrared spectrograph and imager for the Very Large Telescope Interferometer (VLTI) at Paranal. This new interferometric instrument will allow significant advances by opening new avenues in various fundamental research fields: studying the planet-forming region of disks around young stellar objects, understanding the surface structures and mass loss phenomena affecting evolved stars, and probing the environments of black holes in active galactic nuclei. As a first breakthrough, MATISSE will enlarge the spectral domain of current optical interferometers by offering the L and M bands in addition to the N band. This will open a wide wavelength domain, ranging from 2.8 to 13 um, exploring angular scales as small as 3 mas (L band) / 10 mas (N band). As a second breakthrough, MATISSE will allow mid-infrared imaging - closure-phase aperture-synthesis imaging - with up to four Unit Telescopes (UT) or Auxiliary Telescopes (AT) of the VLTI. Moreover, MATISSE will offer a spectral resolution range from R ~ 30 to R ~ 5000. Here, we present one of the main science objectives, the study of protoplanetary disks, that has driven the instrument design and motivated several VLTI upgrades (GRA4MAT and NAOMI). We introduce the physical concept of MATISSE including a description of the signal on the detectors and an evaluation of the expected performances. We also discuss the current status of the MATISSE instrument, which is entering its testing phase, and the foreseen schedule for the next two years that will lead to the first light at Paranal.