Kmt-2018-blg-0029lb: A very low mass-ratio spitzer microlens planet
At q = 1.81 ± 0.20 × 10−5, KMT-2018-BLG-0029Lb has the lowest planet-host mass ratio q of any microlensing planet to date by more than a factor of two. Hence, it is the first planet that probes below the apparent “pile-up” at q = 5–10 ×10−5. The event was observed by Spitzer, yielding a microlens-parallax πE measurement. Combined with a measurement of the Einstein radius θE from finite-source effects during the caustic crossings, these measurements imply masses of the host Mhost = 1.14+0.10 −0.12M⊙ and planet Mplanet = 7.59−0.69+0.75M⊕, system distance DL = 3.38+0.22 −0.26kpc and projected separationa⊥ = 4.27+0.21 −0.23AU. The blended light, which is substantially brighter than the microlensed source, is plausibly due to the lens and could be observed at high resolution immediately.
Publication Source (Journal or Book title)
Journal of the Korean Astronomical Society
Gould, A., Ryu, Y., Novati, S., Zang, W., Albrow, M., Chung, S., Han, C., Hwang, K., Jung, Y., Shin, I., Shvartzvald, Y., Yee, J., Cha, S., Kim, D., Kim, H., Kim, S., Lee, C., Lee, D., Lee, Y., Park, B., Pogge, R., Beichman, C., Bryden, G., Carey, S., Gaudi, B., Henderson, C., Zhu, W., Fouqué, P., Penny, M., Petric, A., Burdullis, T., & Mao, S. (2020). Kmt-2018-blg-0029lb: A very low mass-ratio spitzer microlens planet. Journal of the Korean Astronomical Society, 53 (1), 9-26. https://doi.org/10.5303/JKAS.2020.53.1.9