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A sub-Saturn mass planet, MOA-2009-BLG-319LB


Miyake, N and Sumi, T and Dong, S and Street, R and Mancini, L and Gould, A and Bennett, DP and Tsapras, Y and Yee, JC and Albrow, MD and Bond, IA and Fouque, P and Browne, P and Han, C and Snodgrass, C and Finet, F and Furusawa, K and Harpsoe, C and Allen, W and Hundertmark, M and Freeman, M and Suzuki, D and Abe, F and Botzler, CS and Douchin, D and Fukui, A and Hayashi, F and Hearnshaw, JB and Hosaka, S and Itow, Y and Kamiya, K and Kilmartin, PM and Korpela, A and Lin, W and Ling, CH and Makita, S and Masuda, K and Matsubara, Y and Muraki, Y and Nagayama, T and Nishimoto, K and Ohnishi, K and Perrott, YC and Rattenbury, N and Sailto, T and Skuljan, L and Sullivan, DJ and Sweatman, WL and Tristram, PJ and Wada, K and Yock, PCM and Bolt, G and Bos, M and Christie, GW and DePoy, DL and Drummond, J and Gal-Yam, A and Gaudi, BS and Gorbikov, E and Higgins, D and Hwang, KH and Janczak, J and Kaspi, S and Lee, CU and Koo, JR and Kozlowski, S and Lee, Y and Mallia, F and Maury, A and Maoz, D and McCormick, J and Monard, LAG and Moorhouse, D and Munoz, JA and Natusch, T and Ofek, EO and Pogge, RW and Polishook, D and Santallo, R and Shporer, A and Spector, O and Thornley, G and Allan, A and Bramich, DM and Horne, K and Kains, N and Steele, I and Bozza, V and Burgdorf, MJ and Calchi Novati, S and Dominik, M and Dreizler, S and Glitrup, M and Hessman, FV and Hinse, TC and Jorgensen, UG and Liebig, C and Maier, G and Mathiasen, M and Rahvar, S and Ricci, D and Scarpetta, G and Skottfelt, J and Southworth, J and Surdej, J and Wambsganss, J and Zimmer, F and Batista, V and Beaulieu, JP and Brillant, S and Cassan, A and Cole, A and Corrales, E and Coutures, C and Dieters, S and Greenhill, J and Kubas, D and Menzies, J, A sub-Saturn mass planet, MOA-2009-BLG-319LB, The Astrophysical Journal: An International Review of Astronomy and Astronomical Physics, 728, (2) Article 120. ISSN 0004-637X (2011) [Refereed Article]

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DOI: doi:10.1088/0004-637X/728/2/120


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 thismicrolensing event and enabled its identification as a high-magnification event approximately 24 hr 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, tE, and angular Einstein radius, θE, along with a standard Galactic model indicates a host star mass of ML = 0.38+0.34 -0.18M and a planet mass of Mp = 50+44 -24 M, 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 DL = 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.

Item Details

Item Type:Refereed Article
Keywords:gravitational lensing;micro - planetary systems
Research Division:Physical Sciences
Research Group:Astronomical sciences
Research Field:Stellar astronomy and planetary systems
Objective Division:Expanding Knowledge
Objective Group:Expanding knowledge
Objective Field:Expanding knowledge in the physical sciences
UTAS Author:Cole, A (Professor Andrew Cole)
UTAS Author:Dieters, S (Dr Stefan Dieters)
UTAS Author:Greenhill, J (Dr John Greenhill)
ID Code:68796
Year Published:2011
Web of Science® Times Cited:32
Deposited By:Mathematics and Physics
Deposited On:2011-03-22
Last Modified:2022-08-23

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