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

Denis Defrère; Azzurra Bigioli; Colin Dandumont; Germain Garreau; Romain Laugier; Marc-Antoine Martinod; Olivier Absil; Jean-Philippe Berger; Emilie Bouzerand; Benjamin Courtney-Barrer; Alexandre Emsenhuber; Steve Ertel; Jonathan Gagne; Adrian M. Glauser; Simon Gross; Michael J. Ireland; Harry-Dean Kenchington; Jacques Kluska; Stefan Kraus; Lucas Labadie; Viktor Laborde; Alain Leger; Jarron Leisenring; Jérôme Loicq; Guillermo Martin; Johan Morren; Alexis Matter; Alexandra Mazzoli; Kwinten Missiaen; Muhammad Salman; Marc Ollivier; Gert Raskin; Helene Rousseau; Ahmed Sanny; Simon Verlinden; Bart Vandenbussche; Julien Woillez

arXiv · 2208.08908

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

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Abstract

Hi-5 is the L'-band (3.5-4.0 $\mu$m) 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 (ii) 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.

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Denis Defrère, Azzurra Bigioli, Colin Dandumont, Germain Garreau, Romain Laugier, Marc-Antoine Martinod, Olivier Absil, Jean-Philippe Berger, Emilie Bouzerand, Benjamin Courtney-Barrer, Alexandre Emsenhuber, Steve Ertel, Jonathan Gagne, Adrian M. Glauser, Simon Gross, Michael J. Ireland, Harry-Dean Kenchington, Jacques Kluska, Stefan Kraus, Lucas Labadie, Viktor Laborde, Alain Leger, Jarron Leisenring, Jérôme Loicq, Guillermo Martin, Johan Morren, Alexis Matter, Alexandra Mazzoli, Kwinten Missiaen, Muhammad Salman, Marc Ollivier, Gert Raskin, Helene Rousseau, Ahmed Sanny, Simon Verlinden, Bart Vandenbussche, Julien Woillez. 2022-08-18. L-band nulling interferometry at the VLTI with Asgard/Hi-5: status and plans. https://arxiv.org/abs/2208.08908

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