dc.contributor.author
Demangeon, O. D. S.
dc.contributor.author
Cubillos, P. E.
dc.contributor.author
Singh, V.
dc.contributor.author
Wilson, T. G.
dc.contributor.author
Carone, L.
dc.contributor.author
Bekkelien, A.
dc.contributor.author
Deline, A.
dc.contributor.author
Ehrenreich, D.
dc.contributor.author
Maxted, P. F. L.
dc.contributor.author
Rauer, Heike
dc.date.accessioned
2024-06-26T06:20:48Z
dc.date.available
2024-06-26T06:20:48Z
dc.identifier.uri
https://refubium.fu-berlin.de/handle/fub188/43977
dc.identifier.uri
http://dx.doi.org/10.17169/refubium-43686
dc.description.abstract
Context. WASP-76 b has been a recurrent subject of study since the detection of a signature in high-resolution transit spectroscopy data indicating an asymmetry between the two limbs of the planet. The existence of this asymmetric signature has been confirmed by multiple studies, but its physical origin is still under debate. In addition, it contrasts with the absence of asymmetry reported in the infrared (IR) phase curve.
Aims. We provide a more comprehensive dataset of WASP-76 b with the goal of drawing a complete view of the physical processes at work in this atmosphere. In particular, we attempt to reconcile visible high-resolution transit spectroscopy data and IR broadband phase curves.
Methods. We gathered 3 phase curves, 20 occultations, and 6 transits for WASP-76 b in the visible with the CHEOPS space telescope. We also report the analysis of three unpublished sectors observed by the TESS space telescope (also in the visible), which represents 34 phase curves.
Results. WASP-76 b displays an occultation of 260 ± 11 and 152 ± 10 ppm in TESS and CHEOPS bandpasses respectively. Depending on the composition assumed for the atmosphere and the data reduction used for the IR data, we derived geometric albedo estimates that range from 0.05 ± 0.023 to 0.146 ± 0.013 and from <0.13 to 0.189 ± 0.017 in the CHEOPS and TESS bandpasses, respectively. As expected from the IR phase curves, a low-order model of the phase curves does not yield any detectable asymmetry in the visible either. However, an empirical model allowing for sharper phase curve variations offers a hint of a flux excess before the occultation, with an amplitude of ~40 ppm, an orbital offset of ~ −30°, and a width of ~20º. We also constrained the orbital eccentricity of WASP-76 b to a value lower than 0.0067, with a 99.7% confidence level. This result contradicts earlier proposed scenarios aimed at explaining the asymmetry observed in high-resolution transit spectroscopy.
Conclusions. In light of these findings, we hypothesise that WASP-76 b could have night-side clouds that extend predominantly towards its eastern limb. At this limb, the clouds would be associated with spherical droplets or spherically shaped aerosols of an unknown species, which would be responsible for a glory effect in the visible phase curves.
en
dc.format.extent
35 Seiten
dc.rights.uri
https://creativecommons.org/licenses/by/4.0/
dc.subject
techniques: photometric
en
dc.subject
planets and satellites: atmospheres
en
dc.subject
planets and satellites: composition
en
dc.subject.ddc
500 Naturwissenschaften und Mathematik::520 Astronomie::520 Astronomie und zugeordnete Wissenschaften
dc.title
Asymmetry in the atmosphere of the ultra-hot Jupiter WASP-76 b
dc.type
Wissenschaftlicher Artikel
dcterms.bibliographicCitation.articlenumber
A27
dcterms.bibliographicCitation.doi
10.1051/0004-6361/202348270
dcterms.bibliographicCitation.journaltitle
Astronomy & Astrophysics
dcterms.bibliographicCitation.volume
684
dcterms.bibliographicCitation.url
https://doi.org/10.1051/0004-6361/202348270
refubium.affiliation
Geowissenschaften
refubium.affiliation.other
Institut für Geologische Wissenschaften / Fachrichtung Planetologie und Fernerkundung

refubium.resourceType.isindependentpub
no
dcterms.accessRights.openaire
open access
dcterms.isPartOf.eissn
1432-0746
refubium.resourceType.provider
WoS-Alert