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A Cold Neptune-Mass Planet OGLE-2007-BLG-368Lb: Cold Neptunes are Common

journal contribution
posted on 2023-05-17, 02:34 authored by Sumi, T, Bennett, DP, Bond, IA, Udalski, A, Batista, V, Dominik, M, Fouque, P, Kubas, D, Gould, A, Macintosh, B, Cook, K, Dong, S, Skuljan, L, Cassan, A, Abe, F, Botzler, CS, Fukui, A, Furusawa, K, Hearnshaw, JB, Itow, Y, Kamiya, K, Kilmartin, PM, Korpela, A, Lin, W, Ling, CH, Masuda, K, Matsubara, Y, Miyake, N, Muraki, Y, Nagaya, M, Nagayama, T, Ohnishi, K, Okumura, T, Perrott, YC, Rattenbury, N, Saito, T, Sako, T, Sullivan, DJ, Sweatman, WL, Tristram, PJ, Yock, PCM, Beaulieu, JP, Andrew ColeAndrew Cole, Coutures, C, Duran, MF, Greenhill, J, Jablonski, F, Marboeuf, U, Martioli, E, Pedretti, E, Pejcha, O, Rojo, P, Albrow, MD, Brilliant, S, Bode, M, Bramich, DM, Burgdorf, MJ, Caldwell, JAR, Calitz, H, Corrales, E, Dieters, S, Dominis Prester, D, Donatowicz, J, Kym HillKym Hill, Hoffman, M, Horne, K, Jorgensen, UG, Kains, N, Kane, S, Marquette, JB, Martin, R, Meintjes, P, Menzies, J, Pollard, KR, Sahu, KC, Snodgrass, C, Steele, I, Street, R, Tsapras, Y, Wambsganss, J, Williams, A, Zub, M, Szymanski, MK, Kubiak, M, Pietrzynski, G, Soszynski, I, Szewczyk, O, Wyrzykowski, L, Ulaczyk, K, Allen, W, Christie, GW, DePoy, DL, Gaudi, BS, Han, C, Janczak, J, Lee, CU, McCormick, J, Mallia, F, Monard, B, Natusch, T, Park, BG, Pogge, RW, Santallo, R
We present the discovery of a Neptune-mass planet OGLE-2007-BLG-368Lb with a planet Cstar mass ratio of q = [9.5 2.1] 10−5 via gravitational microlensing. The planetary deviation was detected in real-time thanks to the high cadence of the Microlensing Observations in Astrophysics survey, real-time light-curve monitoring and intensive follow-up observations. A Bayesian analysis returns the stellar mass and distance at Ml = 0.64+0.21 -0.26M andDl = 5.9+0.9 -1.4 kpc, respectively, so themass and separation of the planet areMp = 20+7 -8M and a = 3.3+1.4 -0.8 AU, respectively. This discovery adds another cold Neptune-mass planet to the planetary sample discovered by microlensing, which now comprises four cold Neptune/super-Earths, five gas giant planets, and another sub- Saturn mass planet whose nature is unclear. The discovery of these 10 cold exoplanets by the microlensing method implies that the mass ratio function of cold exoplanets scales as dNpl/d log q q -0.70.2 with a 95% confidence level upper limit of n < -0.35 (where dNpl/d log q qn). As microlensing is most sensitive to planets beyond the snow-line, this implies that Neptune-mass planets are at least three times more common than Jupiters in this region at the 95% confidence level.


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Astrophysical Journal








School of Natural Sciences


Univ Chicago Press

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1427 E 60Th St, Chicago, USA, Il, 60637-2954

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© 2010, American Astronomical Society

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