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

S.~C.~C. Barros, F. Faedi, A. Collier Cameron, T.~A. Lister, J. McCormac, D. Pollacco, E.~K. Simpson, B. Smalley, R.~A. Street, I. Todd, A.~H.~M.~J. Triaud, I. Boisse, F. Bouchy, G. Hébrard, C. Moutou, F. Pepe, D. Queloz, A. Santerne, D. Segransan, S. UdryJ. Bento, O.~W. Butters, B. Enoch, C.~A. Haswell, C. Hellier, F.~P. Keenan, G.~R.~M. Miller, V. Moulds, A.~J. Norton, N. Parley, I. Skillen, C.~A. Watson, R.~G. West, P.~J. Wheatley

Research output: Contribution to journalArticlepeer-review

36 Citations (Scopus)


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 plusmn 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 T$_eff$ = 6150 plusmn 80 K, log g = 4.3 plusmn 0.1, v sin i = 8.6 plusmn 0.4 km s$^-1$, M* = 1.16 plusmn 0.04 M$_⊙$ and R* = 1.33 plusmn 0.03 R$_⊙$, 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 plusmn 0.06 M$_Jup$ and a radius of 1.09 plusmn 0.03 R$_Jup$ giving a density, $$_p$ = 2.1 plusmn 0.1 $$_J$. The high precision of the eccentricity e = 0.0314 plusmn 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 plusmn 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. Photometry and RV data are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr ( or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/525/A54
Original languageEnglish
Pages (from-to)A54
JournalAstronomy and Astrophysics
Publication statusPublished - 1 Jan 2011


  • planets and satellites: detection, stars: individual: WASP-38, techniques: photometric, techniques: radial velocities


Dive into the research topics of 'WASP-38b: a transiting exoplanet in an eccentric, 6.87d period orbit'. Together they form a unique fingerprint.

Cite this