We report the discovery of WASP-4b, a large transiting gas-giant planet with an orbital period of 1.34 days. This is the first planet to be discovered by the SuperWASP-South observatory and CORALIE collaboration and the first planet orbiting a star brighter than 16th magnitude to be discovered in the Southern hemisphere. A simultaneous fit to high-quality lightcurves and precision radial-velocity measurements leads to a planetary mass of 1.22 +/- 0.1 MJup and a planetary radius of 1.42 +/- 0.08 RJup. The host star is USNO-B1.0 0479-0948995, a G7V star of visual magnitude 12.5. As a result of the short orbital period, the predicted surface temperature of the planet is 1776 K, making it an ideal candidate for detections of the secondary eclipse at infrared wavelengths.
@article{arxiv.0801.1509,
title = {WASP-4b: a 12th-magnitude transiting hot-Jupiter in the Southern hemisphere},
author = {D. M. Wilson and M. Gillon and C. Hellier and P. F. L. Maxted and F. Pepe and D. Queloz and D. R. Anderson and A. Collier Cameron and B. Smalley and T. A. Lister and S. J. Bentley and A. Blecha and D. J. Christian and B. Enoch and C. A. Haswell and L. Hebb and K. Horne and J. Irwin and Y. C. Joshi and S. R. Kane and M. Marmier and M. Mayor and N. Parley and D. Pollacco and F. Pont and R. Ryans and D. Segransan and I. Skillen and R. A. Street and S. Udry and R. G. West and P. J. Wheatley},
journal= {arXiv preprint arXiv:0801.1509},
year = {2009}
}
Comments
Added 3 new RV measurements and resultant fit parameters updated. Minor revisions to text. 7 pages incl. 4 figures. Accepted for publication in ApJL