L-band nulling interferometry at the VLTI with Asgard/Hi-5: status and plans

Denis Defrère, A. Bigioli, C. Dandumont, Romain Laugier, G. Garreau, M. Ireland, Jean Philippe Berger, Benjamin Courtney-Barrer, J.J.D. Loicq, More Authors

Research output: Chapter in Book/Conference proceedings/Edited volumeConference contributionScientificpeer-review

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Hi-5 is the L’-band (3.5-4.0 μm) high-contrast imager of Asgard, an instrument suite in preparation for the visitor focus of the VLTI. The system is optimized for high-contrast and high-sensitivity imaging within the diffraction limit of a single UT/AT telescope. It is designed as a double-Bracewell nulling instrument producing spectrally-dispersed (R=20, 400, or 2000) complementary nulling outputs and simultaneous photometric outputs for self-calibration purposes. In this paper, we present an update of the project with a particular focus on the overall architecture, opto-mechanical design of the warm and cold optics, injection system, and development of the photonic beam combiner. The key science projects are to survey (i) nearby young planetary systems near the snow line, where most giant planets are expected to be formed, and (2) nearby main sequence stars near the habitable zone where exozodiacal dust that may hinder the detection of Earth-like planets. We present an update of the expected instrumental performance based on full end-to-end simulations using the new GRAVITY+ specifications of the VLTI and the latest planet formation models.
Original languageEnglish
Title of host publicationOptical and Infrared Interferometry and Imaging VIII
EditorsAntoine Mérand, Stephanie Sallum, Joel Sanchez-Bermudezv
Number of pages16
Publication statusPublished - 2022
EventSPIE Astronomical Telescopes + Instrumentation 2022 - Montréal, Canada
Duration: 17 Jul 202222 Jul 2022

Publication series

NameProceedings of SPIE
ISSN (Electronic)0277-786X


ConferenceSPIE Astronomical Telescopes + Instrumentation 2022

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