A sub-Saturn Mass Planet, MOA-2009-BLG-319Lb
Abstract
We report the gravitational microlensing discovery of a sub-Saturn mass planet, MOA-2009-BLG-319Lb, orbiting a K or M-dwarf star in the inner Galactic disk or Galactic bulge. The high cadence observations of the MOA-II survey discovered this microlensing event and enabled its identification as a high magnification event approximately 24 hours prior to peak magnification. As a result, the planetary signal at the peak of this light curve was observed by 20 different telescopes, which is the largest number of telescopes to contribute to a planetary discovery to date. The microlensing model for this event indicates a planet-star mass ratio of q = (3.95 +/- 0.02) x 10^{-4} and a separation of d = 0.97537 +/- 0.00007 in units of the Einstein radius. A Bayesian analysis based on the measured Einstein radius crossing time, t_E, and angular Einstein radius, \theta_E, along with a standard Galactic model indicates a host star mass of M_L = 0.38^{+0.34}_{-0.18} M_{Sun} and a planet mass of M_p = 50^{+44}_{-24} M_{Earth}, which is half the mass of Saturn. This analysis also yields a planet-star three-dimensional separation of a = 2.4^{+1.2}_{-0.6} AU and a distance to the planetary system of D_L = 6.1^{+1.1}_{-1.2} kpc. This separation is ~ 2 times the distance of the snow line, a separation similar to most of the other planets discovered by microlensing.
Cite
@article{arxiv.1010.1809,
title = {A sub-Saturn Mass Planet, MOA-2009-BLG-319Lb},
author = {N. Miyake and T. Sumi and Subo Dong and R. Street and L. Mancini and A. Gould and D. P. Bennett and Y. Tsapras and J. C. Yee and M. D. Albrow and I. A. Bond and P. Fouque and P. Browne and C. Han and C. Snodgrass and F. Finet and K. Furusawa and K. Harpsoe and W. Allen and M. Hundertmark and M. Freeman and D. Suzuki and F. Abe and C. S. Botzler and D. Douchin and A. Fukui and F. Hayashi and J. B. Hearnshaw and S. Hosaka and Y. Itow and K. Kamiya and P. M. Kilmartin and A. Korpela and W. Lin and C. H. Ling and S. Makita and K. Masuda and Y. Matsubara and Y. Muraki and T. Nagayama and K. Nishimoto and K. Ohnishi and Y. C. Perrott and N. Rattenbury and To. Saito and L. Skuljan and D. J. Sullivan and W. L. Sweatman and P. J. Tristram and K. Wada and P. C. M. Yock and The MOA Collaboration and G. Bolt and M. Bos and G. W. Christie and D. L. DePoy and J. Drummond and A. Gal-Yam and B. S. Gaudi and E. Gorbikov and D. Higgins and K. -H. Hwang J. Janczak and S. Kaspi and C. -U. Lee and J. -R. Koo and S. Koz lowski and Y. Lee and F. Mallia and A. Maury and D. Maoz and J. McCormick and L. A. G. Monard and D. Moorhouse and J. A. Mu~noz and T. Natusch and E. O. Ofek and R. W. Pogge and D. Polishook and R. Santallo and A. Shporer and O. Spector and G. Thornley and The Micro FUN Collaboration and A. Allan and D. M. Bramich and K. Horne and N. Kains and I. Steele and The RoboNet Collaboration and V. Bozza and M. J. Burgdorf and S. Calchi Novati and M. Dominik and S. Dreizler and M. Glitrup and F. V. Hessman and T. C. Hinse and U. G. Jorgensen and C. Liebig and G. Maier and M. Mathiasen and S. Rahvar and D. Ricci and G. Scarpetta and J. Skottfelt and J. Southworth and J. Surdej and J. Wambsganss and F. Zimmer and The MiNDSTEp Consortium and V. Batista and J. P. Beaulieu and S. Brillant and A. Cassan and A. Cole and E. Corrales and Ch. Coutures and S. Dieters and J. Greenhill and D. Kubas and J. Menzies and The PLANET Collaboration},
journal= {arXiv preprint arXiv:1010.1809},
year = {2015}
}
Comments
accepted to ApJ, 28 pages, 6 figures, 3 tables