English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
Add to Basket
  Local TagsStatisticsRelease HistoryDetailsSummary

Released
Journal Article

ACCESS: Ground-based Optical Transmission Spectroscopy of the Hot Jupiter WASP-4b

MPS-Authors

Bixel,  Alex
Max Planck Institute for Astronomy, Max Planck Society and Cooperation Partners;

Rackham,  Benjamin V.
Max Planck Institute for Astronomy, Max Planck Society and Cooperation Partners;

Apai,  Dániel
Max Planck Institute for Astronomy, Max Planck Society and Cooperation Partners;

Espinoza,  Néstor
Max Planck Institute for Astronomy, Max Planck Society and Cooperation Partners;

López-Morales,  Mercedes
Max Planck Institute for Astronomy, Max Planck Society and Cooperation Partners;

Osip,  David
Max Planck Institute for Astronomy, Max Planck Society and Cooperation Partners;

Jordán,  Andrés
Max Planck Institute for Astronomy, Max Planck Society and Cooperation Partners;

McGruder,  Chima
Max Planck Institute for Astronomy, Max Planck Society and Cooperation Partners;

Weaver,  Ian
Max Planck Institute for Astronomy, Max Planck Society and Cooperation Partners;

External Resource
Fulltext (public)
There are no public fulltexts stored in PuRe
Supplementary Material (public)
There is no public supplementary material available
Citation

Bixel, A., Rackham, B. V., Apai, D., Espinoza, N., López-Morales, M., Osip, D., et al. (2019). ACCESS: Ground-based Optical Transmission Spectroscopy of the Hot Jupiter WASP-4b. The Astronomical Journal, 157.


Cite as: http://hdl.handle.net/21.11116/0000-0005-D40F-C
Abstract
We present an optical transmission spectrum of the atmosphere of WASP-4b obtained through observations of four transits with Magellan/IMACS, as part of the Arizona-CfA-Católica-Carnegie Exoplanet Spectroscopy Survey (ACCESS). Using a Bayesian approach to atmospheric retrieval, we find no evidence for scattering or absorption features in our transit spectrum. Our models include a component to model the transit light source effect (spectral contamination from unocculted spots on the stellar photosphere), which we show can have a marked impact on the observed transmission spectrum for reasonable spot-covering fractions (<5%) this is the first such analysis for WASP-4b. We are also able to fit for the size and temperature contrast of spots observed during the second and third transits, finding evidence for both small, cool and large, warm spot-like features on the photosphere. Finally, we compare our results to those published by Huitson et al. using Gemini/GMOS and May et al. using IMACS, and we find that our data are in agreement.