Details

Autor(en) / Beteiligte

• Specht, D
• Poleski, R
• Penny, M T
• Kerins, E
• McDonald, I
• Lee, Chung-Uk
• Udalski, A
• Bond, I A
• Shvartzvald, Y
• Zang, Weicheng
• Street, R A
• Hogg, D W
• Gaudi, B S
• Barclay, T
• Barentsen, G
• Howell, S B
• Mullally, F
• Henderson, C B
• Bryson, S T
• Caldwell, D A
• Haas, M R
• Van Cleve, J E
• Larson, K
• McCalmont, K
• Peterson, C
• Putnam, D
• Ross, S
• Packard, M
• Reedy, L
• Albrow, Michael D
• Chung, Sun-Ju
• Kil Jung, Youn
• Gould, Andrew
• Han, Cheongho
• Hwang, Kyu-Ha
• Ryu, Yoon-Hyun
• Shin, In-Gu
• Yang, Hongjing
• Yee, Jennifer C
• Cha, Sang-Mok
• Kim, Dong-Jin
• Kim, Seung-Lee
• Lee, Dong-Joo
• Lee, Yongseok
• Park, Byeong-Gon
• Pogge, Richard W
• Szymański, M K
• Soszyński, I
• Ulaczyk, K
• Pietrukowicz, P
• Kozłowski, Sz
• Skowron, J
• Mróz, P
• Mao, Shude
• Fouqué, Pascal
• Zhu, Wei
• Abe, F
• Barry, R
• Bennett, D P
• Bhattacharya, A
• Fukui, A
• Fujii, H
• Hirao, Y
• Itow, Y
• Kirikawa, R
• Kondo, I
• Koshimoto, N
• Matsubara, Y
• Matsumoto, S
• Miyazaki, S
• Muraki, Y
• Olmschenk, G
• Ranc, C
• Okamura, A
• Rattenbury, N J
• Satoh, Y
• Sumi, T
• Suzuki, D
• Silva, S I
• Toda, T
• Tristram, P J
• Vandorou, A
• Yama, H
• Beichman, C
• Bryden, G
• Calchi Novati, S

Titel

Kepler K2 Campaign 9 – II. First space-based discovery of an exoplanet using microlensing

Ist Teil von

• Monthly notices of the Royal Astronomical Society, 2023-02, Vol.520 (4), p.6350-6366

Ort / Verlag

Oxford University Press

Erscheinungsjahr

2023

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• ABSTRACT We present K2-2016-BLG-0005Lb, a densely sampled, planetary binary caustic-crossing microlensing event found from a blind search of data gathered from Campaign 9 of the Kepler K2 mission (K2C9). K2-2016-BLG-0005Lb is the first bound microlensing exoplanet discovered from space-based data. The event has caustic entry and exit points that are resolved in the K2C9 data, enabling the lens-source relative proper motion to be measured. We have fitted a binary microlens model to the Kepler data and to simultaneous observations from multiple ground-based surveys. Whilst the ground-based data only sparsely sample the binary caustic, they provide a clear detection of parallax that allows us to break completely the microlensing mass-position-velocity degeneracy and measure the planet’s mass directly. We find a host mass of 0.58 ± 0.04 M⊙ and a planetary mass of 1.1 ± 0.1 MJ. The system lies at a distance of 5.2 ± 0.2 kpc from Earth towards the Galactic bulge, more than twice the distance of the previous most distant planet found by Kepler. The sky-projected separation of the planet from its host is found to be 4.2 ± 0.3 au which, for circular orbits, deprojects to a host separation $a = 4.4^{+1.9}_{-0.4}$ au and orbital period $P = 13^{+9}_{-2}$ yr. This makes K2-2016-BLG-0005Lb a close Jupiter analogue orbiting a low-mass host star. According to current planet formation models, this system is very close to the host mass threshold below which Jupiters are not expected to form. Upcoming space-based exoplanet microlensing surveys by NASA’s Nancy Grace Roman Space Telescope and, possibly, ESA’s Euclid mission, will provide demanding tests of current planet formation models.