MOA-2010-BLG-328Lb: a sub-Neptune orbiting very late M dwarf ?
Creators: name: Furusawa, K.
name: Udalski, A.
name: Sumi, T.
name: Bennett, D. P.
name: Bond, I. A.
name: Gould, A.
name: Jorgensen, U. G.
name: Snodgrass, C.
name: Prester, D. Dominis
name: Albrow, M. D.
name: Abe, F.
name: Botzler, C. S.
name: Chote, P.
name: Freeman, M.
name: Fukui, A.
name: Harris, P.
name: Itow, Y.
name: Ling, C. H.
name: Masuda, K.
name: Matsubara, Y.
name: Miyake, N.
name: Muraki, Y.
name: Ohnishi, K.
name: Rattenbury, N. J.
name: Saito, To.
name: Sullivan, D. J.
name: Suzuki, D.
name: Sweatman, W. L.
name: Tristram, P. J.
name: Wada, K.
name: Yock, P. C. M.
name: Szymanski, M. K.
name: Soszynski, I.
name: Kubiak, M.
name: Poleski, R.
name: Ulaczyk, K.
name: Pietrzynski, G.
name: Wyrzykowski, L.
name: Choi, J. Y.
name: Christie, G. W.
name: DePoy, D. L.
name: Dong, S.
name: Drummond, J.
name: Gaudi, B. S.
name: Han, C.
name: Hung, L. -W.
name: Jung, Y. -K.
name: Lee, C. -U.
name: McCormick, J.
name: Moorhouse, D.
name: Natusch, T.
name: Nola, M.
name: Ofek, E.
name: Park, B. G.
name: Park, H.
name: Pogge, R. W.
name: Shin, I. -G.
name: Skowron, J.
name: Thornley, G.
name: Yee, J. C.
name: Alsubai, K. A.
name: Bozza, V.
name: Browne, P.
name: Burgdorf, M. J.
name: Novati, S. Calchi
name: Dodds, P.
name: Dominik, M.
name: Finet, F.
name: Gerner, T.
name: Hardis, S.
name: Harpsoe, K.
name: Hinse, T. C.
name: Hundertmark, M.
name: Kains, N.
name: Kerins, E.
name: Liebig, C.
name: Mancini, L.
name: Mathiasen, M.
name: Penny, M. T.
name: Proft, S.
name: Rahvar, S.
name: Ricci, D.
name: Scarpetta, G.
name: Schafer, S.
name: Schonebeck, F.
name: Southworth, J.
name: Surdej, J.
name: Wambsganss, J.
name: Street, R. A.
name: Bramich, D. M.
name: Steele, I. A.
name: Tsapras, Y.
name: Horne, K.
name: Donatowicz, J.
name: Sahu, K. C.
name: Bachelet, E.
name: Batista, V.
name: Beatty, T. G.
name: Beaulieu, J. -P.
name: Bennett, C. S.
name: Black, C.
name: Bowens-Rubin, R.
name: Brillant, S.
name: Caldwell, J. A. R.
name: Cassan, A.
name: Cole, A. A.
name: Corrales, E.
name: Coutures, C.
name: Dieters, S.
name: Fouque, P.
name: Greenhill, J.
name: Henderson, C. B.
name: Kubas, D.
name: Marquette, J. -B.
name: Martin, R.
name: Menzies, J. W.
name: Shappee, B.
name: Williams, A.
name: Wouters, D.
name: van Saders, J.
name: Zellem, R.
name: Zub, M.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: We analyze the planetary microlensing event MOA-2010-BLG-328. The best fit yields host and planetary masses of Mh = 0.11+/-0.01 M_{sun} and Mp = 9.2+/-2.2M_Earth, corresponding to a very late M dwarf and sub-Neptune-mass planet, respectively. The system lies at DL = 0.81 +/- 0.10 kpc with projected separation r = 0.92 +/- 0.16 AU. Because of the host's a-priori-unlikely close distance, as well as the unusual nature of the system, we consider the possibility that the microlens parallax signal, which determines the host mass and distance, is actually due to xallarap (source orbital motion) that is being misinterpreted as parallax. We show a result that favors the parallax solution, even given its close host distance. We show that future high-resolution astrometric measurements could decisively resolve the remaining ambiguity of these solutions.
description: 30 pages, 6 figures. accepted for publication in ApJ. Figure 1 and 2 are updated