Hint of an exocomet transit in the CHEOPS light curve of HD 172555
(2023) In Astronomy & Astrophysics 671.- Abstract
- HD 172555 is a young (∼20 Myr) A7V star surrounded by a 10 au wide debris disk suspected to be replenished partly by collisions between large planetesimals. Small evaporating transiting bodies, that is exocomets, have also been detected in this system by spectroscopy. After β Pictoris, this is another example of a system possibly witnessing a phase of the heavy bombardment of planetesimals. In such a system, small bodies trace dynamical evolution processes. We aim to constrain their dust content by using transit photometry. We performed a 2-day-long photometric monitoring of HD 172555 with the CHEOPS space telescope in order to detect shallow transits of exocomets with a typical expected duration of a few hours. The large oscillations in... (More)
- HD 172555 is a young (∼20 Myr) A7V star surrounded by a 10 au wide debris disk suspected to be replenished partly by collisions between large planetesimals. Small evaporating transiting bodies, that is exocomets, have also been detected in this system by spectroscopy. After β Pictoris, this is another example of a system possibly witnessing a phase of the heavy bombardment of planetesimals. In such a system, small bodies trace dynamical evolution processes. We aim to constrain their dust content by using transit photometry. We performed a 2-day-long photometric monitoring of HD 172555 with the CHEOPS space telescope in order to detect shallow transits of exocomets with a typical expected duration of a few hours. The large oscillations in the light curve indicate that HD 172555 is a δ Scuti pulsating star. After removing those dominating oscillations, we found a hint of a transient absorption. If fitted with an exocomet transit model, it would correspond to an evaporating body passing near the star at a distance of 6.8±1.4R∗ (or 0.05±0.01 au) with a radius of 2.5 km. These properties are comparable to those of the exocomets already found in this system using spectroscopy, as well as those found in the β Pic system. The nuclei of the Solar System's Jupiter family comets, with radii of 2-6 km, are also comparable in size. This is the first piece of evidence of an exocomet photometric transit detection in the young system of HD 172555. © 2023 EDP Sciences. All rights reserved. (Less)
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- author
- Kiefer, F. ; Davies, M.B. LU and Walton, N.A.
- author collaboration
- organization
- publishing date
- 2023
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Circumstellar matter, Comets: general, Stars: individual: HD 172555, Stars: variables: δ Scuti, Techniques: photometric, Comets, Photometry, Circumstellar matters, Debris disk, Light curves, Pictoris, Star: variable: δ scuti, Stars: Individual: HD 172555, Stars: variables, δ Scuti, Stars
- in
- Astronomy & Astrophysics
- volume
- 671
- article number
- A25
- publisher
- EDP Sciences
- external identifiers
-
- scopus:85149669984
- ISSN
- 0004-6361
- DOI
- 10.1051/0004-6361/202245104
- language
- English
- LU publication?
- yes
- id
- acc74be8-cd9e-4ef3-95bb-0db8b2515707
- date added to LUP
- 2023-10-30 13:53:56
- date last changed
- 2023-10-30 13:53:56
@article{acc74be8-cd9e-4ef3-95bb-0db8b2515707,
abstract = {{HD 172555 is a young (∼20 Myr) A7V star surrounded by a 10 au wide debris disk suspected to be replenished partly by collisions between large planetesimals. Small evaporating transiting bodies, that is exocomets, have also been detected in this system by spectroscopy. After β Pictoris, this is another example of a system possibly witnessing a phase of the heavy bombardment of planetesimals. In such a system, small bodies trace dynamical evolution processes. We aim to constrain their dust content by using transit photometry. We performed a 2-day-long photometric monitoring of HD 172555 with the CHEOPS space telescope in order to detect shallow transits of exocomets with a typical expected duration of a few hours. The large oscillations in the light curve indicate that HD 172555 is a δ Scuti pulsating star. After removing those dominating oscillations, we found a hint of a transient absorption. If fitted with an exocomet transit model, it would correspond to an evaporating body passing near the star at a distance of 6.8±1.4R∗ (or 0.05±0.01 au) with a radius of 2.5 km. These properties are comparable to those of the exocomets already found in this system using spectroscopy, as well as those found in the β Pic system. The nuclei of the Solar System's Jupiter family comets, with radii of 2-6 km, are also comparable in size. This is the first piece of evidence of an exocomet photometric transit detection in the young system of HD 172555. © 2023 EDP Sciences. All rights reserved.}},
author = {{Kiefer, F. and Davies, M.B. and Walton, N.A.}},
issn = {{0004-6361}},
keywords = {{Circumstellar matter; Comets: general; Stars: individual: HD 172555; Stars: variables: δ Scuti; Techniques: photometric; Comets; Photometry; Circumstellar matters; Debris disk; Light curves; Pictoris; Star: variable: δ scuti; Stars: Individual: HD 172555; Stars: variables; δ Scuti; Stars}},
language = {{eng}},
publisher = {{EDP Sciences}},
series = {{Astronomy & Astrophysics}},
title = {{Hint of an exocomet transit in the CHEOPS light curve of HD 172555}},
url = {{http://dx.doi.org/10.1051/0004-6361/202245104}},
doi = {{10.1051/0004-6361/202245104}},
volume = {{671}},
year = {{2023}},
}