Asgard/NOTT: L-band nulling interferometry at the VLTI[0.5em] IV. Prospects for characterising hot exozodiacal dust
11 affiliations
- 1Institute of Theoretical Physics and Astrophysics, University of Kiel , Leibnizstr. 15, 24118 Kiel ,
- 2Institute of Astronomy , KU Leuven, Celestijnenlaan 200D, 3001 Leuven ,
- 3The University of Arizona Department of Astronomy and Steward Observatory, , 933 North Cherry Ave, Tucson, AZ 85721 ,
- 4Large Binocular Telescope Observatory, The University of Arizona , 933 North Cherry Ave, Tucson, AZ 85721 ,
- 5Sterrenkundig Observatorium , Ghent University, Krijgslaan 281-S9, B-9000 Gent ,
- 6Hamburger Sternwarte, University of Hamburg , Gojenbergsweg 112, 21029 Hamburg ,
- 7STAR Institute, Université de Liége , Allée du Six Août 19c, B-4000 Liége ,
- 8Exoplanets and Habitability , ETH Zürich, Wolfgang-Pauli-Str. 27, 8093 Zürich ,
- 9Université Grenoble Alpes , CNRS, IPAG, 38000 Grenoble ,
- 10NASA Goddard Space Flight Center , 8800 Greenbelt Road, Greenbelt, MD 20771-2400 ,
- 11University of Warwick Department of Physics, , Gibbet Hill Road, Coventry CV4 7AL ,
Abstract
Near-infrared interferometric surveys have revealed extended emission around the photosphere of ≈40 main-sequence stars, attributed to the presence of hot exozodiacal dust (HEZD). A promising technique for investigating this phenomenon is nulling interferometry. The VLTI nulling interferometer NOTT (Nulling Observations of exoplaneTs and dusT) is designed to characterise exoplanets and HEZD in the L′ band (3.5 − 4.0 μm). We aim to assess NOTT’s potential for the detection and characterisation of HEZD with various instrumental and model parameter configurations. We model the HEZD as an optically thin dust ring, using the nearby Sun-like star τ Ceti with HEZD as a reference model. Applying the end-to-end nulling tool SCIFYsim to model the instrumental response of NOTT to simulated HEZD brightness distributions, we evaluate how variations in HEZD and instrumental parameters affect NOTT’s key observables: the photon flux rate and the null depth. We demonstrate that NOTT is capable of disentangling stellar and dust contributions to the signal and detecting HEZD. The null depth and photon flux rate are sensitive to the HEZD geometry, with inclination, position angle, and ring location having the strongest impact on the signal. Although the detailed temporal signatures are target-specific, the results can be generalised to other systems. NOTT has the potential to deliver unprecedented sensitivity for HEZD observations, granting access to detailed information through spectral dispersion, beam-combination schemes, and exploitation of sky rotation. This enables more sensitive HEZD detections than is possible with current instruments, and improved spatial constraints on the dust, as well as variability studies.
Related
- Asgard/NOTT: Status of laboratory nulling performance
- Status and performance of the Asgard/NOTT cold nulling camera
- Characterization of the stabilized nulling interferometry testbed PERSÉE
- Investigating the subpulse drifting and periodic nulling behavior of the long-period pulsar PSR J1831-1223 with FAST
- Silencing the stellar glare with kernel-nulling and active phase control on photonic chips
BibTeX
@article{ollmann2026asgardnott,
title = {{Asgard/NOTT: L-band nulling interferometry at the VLTI[0.5em] IV. Prospects for characterising hot exozodiacal dust}},
author = {K Ollmann and R Laugier and J P Scott and T A Stuber and S Ertel and D Defrére and F Kirchschlager and O Absil and G Garreau and J C Augereau and W Danchi and T D Pearce and S Wolf},
journal = {Monthly Notices of the Royal Astronomical Society},
year = {2026},
month = oct,
doi = {10.1093/mnras/stag2034},
url = {https://academic.oup.com/mnras/advance-article/doi/10.1093/mnras/stag2034/8997911},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Asgard/NOTT: L-band nulling interferometry at the VLTI[0.5em] IV. Prospects for characterising hot exozodiacal dust
AU - K Ollmann
AU - R Laugier
AU - J P Scott
AU - T A Stuber
AU - S Ertel
AU - D Defrére
AU - F Kirchschlager
AU - O Absil
AU - G Garreau
AU - J C Augereau
AU - W Danchi
AU - T D Pearce
AU - S Wolf
PY - 2026
DA - 2026/10/24
JO - Monthly Notices of the Royal Astronomical Society
DO - 10.1093/mnras/stag2034
UR - https://academic.oup.com/mnras/advance-article/doi/10.1093/mnras/stag2034/8997911
AB - Near-infrared interferometric surveys have revealed extended emission around the photosphere of ≈40 main-sequence stars, attributed to the presence of hot exozodiacal dust (HEZD). A promising technique for investigating this phenomenon is nulling interferometry. The VLTI nulling interferometer NOTT (Nulling Observations of exoplaneTs and dusT) is designed to characterise exoplanets and HEZD in the L′ band (3.5 − 4.0 μm). We aim to assess NOTT’s potential for the detection and characterisation of HEZD with various instrumental and model parameter configurations. We model the HEZD as an optically thin dust ring, using the nearby Sun-like star τ Ceti with HEZD as a reference model. Applying the end-to-end nulling tool SCIFYsim to model the instrumental response of NOTT to simulated HEZD brightness distributions, we evaluate how variations in HEZD and instrumental parameters affect NOTT’s key observables: the photon flux rate and the null depth. We demonstrate that NOTT is capable of disentangling stellar and dust contributions to the signal and detecting HEZD. The null depth and photon flux rate are sensitive to the HEZD geometry, with inclination, position angle, and ring location having the strongest impact on the signal. Although the detailed temporal signatures are target-specific, the results can be generalised to other systems. NOTT has the potential to deliver unprecedented sensitivity for HEZD observations, granting access to detailed information through spectral dispersion, beam-combination schemes, and exploitation of sky rotation. This enables more sensitive HEZD detections than is possible with current instruments, and improved spatial constraints on the dust, as well as variability studies.
SN - 0035-8711
SN - 1365-2966
ER -