The HOSTS survey for exozodiacal dust: Observational results from the complete survey
Abstract
The Large Binocular Telescope Interferometer (LBTI) enables nulling interferometric observations across the N band (8 to 13 um) to suppress a star's bright light and probe for faint circumstellar emission. We present and statistically analyze the results from the LBTI/HOSTS (Hunt for Observable Signatures of Terrestrial Systems) survey for exozodiacal dust. By comparing our measurements to model predictions based on the Solar zodiacal dust in the N band, we estimate a 1 sigma median sensitivity of 23 zodis for early type stars and 48 zodis for Sun-like stars, where 1 zodi is the surface density of habitable zone (HZ) dust in the Solar system. Of the 38 stars observed, 10 show significant excess. A clear correlation of our detections with the presence of cold dust in the systems was found, but none with the stellar spectral type or age. The majority of Sun-like stars have relatively low HZ dust levels (best-fit median: 3 zodis, 1 sigma upper limit: 9 zodis, 95% confidence: 27 zodis based on our N band measurements), while ~20% are significantly more dusty. The Solar system's HZ dust content is consistent with being typical. Our median HZ dust level would not be a major limitation to the direct imaging search for Earth-like exoplanets, but more precise constraints are still required, in particular to evaluate the impact of exozodiacal dust for the spectroscopic characterization of imaged exo-Earth candidates.
Cite
@article{arxiv.2003.03499,
title = {The HOSTS survey for exozodiacal dust: Observational results from the complete survey},
author = {Steve Ertel and Denis Defrère and Philip M. Hinz and Bertrand Mennesson and Grant M. Kennedy and William C. Danchi and Christopher Gelino and John M. Hill and William F. Hoffmann and Johan Mazoyer and George Rieke and Andrew Shannon and Karl Stapelfeldt and Eckhart Spalding and Jordan M. Stone and Amali Vaz and Alycia J. Weinberger and Phil Willems and Olivier Absil and Paul Arbo and Vanessa P. Bailey and Charles Beichman and Geoffrey Bryden and Elwood C. Downey and Olivier Durney and Simone Esposito and Andras Gaspar and Paul Grenz and Chris A. Haniff and Jarron M. Leisenring and Lindsay Marion and Tom J. McMahon and Rafael Millan-Gabet and Oscar M. Montoya and Katie M. Morzinski and Saavidra Perera and Enrico Pinna and Jörg-Uwe Pott and Jennifer Power and Alfio Puglisi and Aki Roberge and Eugene Serabyn and Andrew J. Skemer and Kate Y. L. Su and Vidhya Vaitheeswaran and Mark C. Wyatt},
journal= {arXiv preprint arXiv:2003.03499},
year = {2020}
}
Comments
accepted for publication in AJ