Title：Super-Earths are Common in Jupiter-like Orbits

Speaker：Weicheng Zang (Harvard University)

Time: 3: 00pm, July 05th (Friday)

Tencent Meeting：935-503-762 password: 6360

Location: Lecture Hall, 3rd floor

Abstract：

Super-Earths and mini-Neptunes are absent in the relatively planet-rich Solar System, but the transit and radial velocity methods have demonstrated that they are common in short-period orbits. The standard core accretion planet formation theory predicts numerous "failed gas giant cores" in the wide orbits (>~ 1 AU), with masses of Super-Earth/mini-Neptune masses. The gravitational microlensing technique is currently the only method that can probe low-mass wide-orbit planets, but before 2020 such planets were barely detected, indicating a paucity of "failed gas giant cores". Since 2020, I have been leading two projects to capture "failed gas giant cores", which detected about 10 planets smaller than the detection record by 2020, suggesting that "failed gas giant cores" are common (about 1 per star). I will also introduce the statistical result from the largest microlensing planetary sample, from Earths to super-Jupiters, and the future missions for microlensing planets.

CV：

Weicheng Zang is a CfA Fellow at the Center for Astrophysics | Harvard & Smithsonian. He obtained the Ph.D. from the Department of Astronomy at Tsinghua University in 2022. His research focuses on the detection and characterization of wide-orbit and free-floating planets using the gravitational microlensing technique.