MOA-2011-BLG-293Lb: First Microlensing Planet possibly in the Habitable Zone

Дата и время публикации : 2013-10-14T14:53:34Z

Авторы публикации и институты :
V. Batista
J. -P. Beaulieu
A. Gould
D. P. Bennett
J. C Yee
A. Fukui
B. S. Gaudi
T. Sumi
A. Udalski

Ссылка на журнал-издание: Ссылка на журнал-издание не найдена
Коментарии к cтатье: Accepted by ApJ, 21 pages, 4 figures
Первичная категория: astro-ph.EP

Все категории : astro-ph.EP

Краткий обзор статьи: We used Keck adaptive optics observations to identify the first planet discovered by microlensing to lie in or near the habitable zone, i.e., at projected separation $r_perp=1.1pm 0.1,$AU from its $M_{L}=0.86pm 0.06,M_odot$ host, being the highest microlensing mass definitely identified. The planet has a mass $m_p = 4.8pm 0.3,M_{rm Jup}$, and could in principle have habitable moons. This is also the first planet to be identified as being in the Galactic bulge with good confidence: $D_L=7.72pm 0.44$ kpc. The planet/host masses and distance were previously not known, but only estimated using Bayesian priors based on a Galactic model (Yee et al. 2012). These estimates had suggested that the planet might be a super-Jupiter orbiting an M dwarf, a very rare class of planets. We obtained high-resolution $JHK$ images using Keck adaptive optics to detect the lens and so test this hypothesis. We clearly detect light from a G dwarf at the position of the event, and exclude all interpretations other than that this is the lens with high confidence (95%), using a new astrometric technique. The calibrated magnitude of the planet host star is $H_{L}=19.16pm 0.13$. We infer the following probabilities for the three possible orbital configurations of the gas giant planet: 53% to be in the habitable zone, 35% to be near the habitable zone, and 12% to be beyond the snow line, depending on the atmospherical conditions and the uncertainties on the semimajor axis.

Category: Physics