The Open UniversitySkip to content

WASP-38b: a transiting exoplanet in an eccentric, 6.87d period orbit

Barros, S. C. C.; Faedi, F.; Collier Cameron, A.; Lister, T. A.; McCormac, J.; Pollacco, D.; Simpson, E. K.; Smalley, B.; Street, R. A.; Todd, I.; Triaud, A. H. M. J.; Boisse, I.; Bouchy, F.; Hébrard, G.; Moutou, C.; Pepe, F.; Queloz, D.; Santerne, A.; Segransan, D.; Udry, S.; Bento, J.; Butters, O. W.; Enoch, B.; Haswell, C. A.; Hellier, C.; Keenan, F. P.; Miller, G. R. M.; Moulds, V.; Norton, A. J.; Parley, N.; Skillen, I.; Watson, C. A.; West, R. G. and Wheatley, P. J. (2011). WASP-38b: a transiting exoplanet in an eccentric, 6.87d period orbit. Astronomy & Astrophysics, 525, article no. A54.

Full text available as:
PDF (Version of Record) - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
Download (1162Kb)
DOI (Digital Object Identifier) Link:
Google Scholar: Look up in Google Scholar


Aims: We report the discovery of WASP-38b, a long period transiting planet in an eccentric 6.871815 day orbit. The transit epoch is 2 455 335.92050 ± 0.00074 (HJD) and the transit duration is 4.663 h.

Methods: WASP-38b's discovery was enabled due to an upgrade to the SuperWASP-North cameras. We performed a spectral analysis of the host star HD 146389/BD+10 2980 that yielded Teff = 6150 ± 80 K, log g = 4.3 ± 0.1, v sin i = 8.6 ± 0.4 km s-1, M* = 1.16 ± 0.04 Mʘand R* = 1.33 ± 0.03 Rʘ, consistent with a dwarf of spectral type F8. Assuming a main-sequence mass-radius relation for the star, we fitted simultaneously the radial velocity variations and the transit light curves to estimate the orbital and planetary parameters.

Results: The planet has a mass of 2.69 ± 0.06 MJup and a radius of 1.09 ± 0.03 RJup giving a density, ρp = 2.1 ± 0.1 ρJ. The high precision of the eccentricity e = 0.0314 ± 0.0044 is due to the relative transit timing from the light curves and the RV shape. The planet equilibrium temperature is estimated at 1292 ± 33 K. WASP-38b is the longest period planet found by SuperWASP-North and with a bright host star (V = 9.4 mag), is a good candidate for followup atmospheric studies.

Item Type: Journal Article
Copyright Holders: 2010 ESO
ISSN: 1432-0746
Extra Information: 6 pp.
Keywords: planet and satellite detection; WASP-38; photometric techniques; radial velocity techniques
Academic Unit/Department: Faculty of Science, Technology, Engineering and Mathematics (STEM) > Physical Sciences
Faculty of Science, Technology, Engineering and Mathematics (STEM)
Interdisciplinary Research Centre: Centre for Earth, Planetary, Space and Astronomical Research (CEPSAR)
Item ID: 25287
Depositing User: Andrew Norton
Date Deposited: 04 Jan 2011 16:12
Last Modified: 06 Oct 2016 02:14
Share this page:


Scopus Citations

Download history for this item

These details should be considered as only a guide to the number of downloads performed manually. Algorithmic methods have been applied in an attempt to remove automated downloads from the displayed statistics but no guarantee can be made as to the accuracy of the figures.

▼ Automated document suggestions from open access sources

Actions (login may be required)

Policies | Disclaimer

© The Open University   + 44 (0)870 333 4340