Papers › MOA-2009-BLG-319Lb: A Sub-Saturn Planet Inside the Predicted Mass Desert
MOA-2009-BLG-319Lb: A Sub-Saturn Planet Inside the Predicted Mass Desert
Sean K. Terry, Aparna Bhattacharya, David P. Bennett, Jean-Phillipe Beaulieu, Naoki Koshimoto, Joshua W. Blackman, Ian A. Bond, Andrew A. Cole, Calen B. Henderson, Jessica R. Lu, Jean Baptiste Marquette, Clement Ranc, Aikaterini Vandorou
The archive published only this paper's code-link row. Authors, date and abstract are from arXiv's metadata (CC0), read from the Kaggle arXiv metadata snapshot of 2026-09-12 where its title matched the archive's; the title is the archive's.
We present an adaptive optics (AO) analysis of images from the Keck-II telescope NIRC2 instrument of the planetary microlensing event MOA-2009-BLG-319. The ∼10 year baseline between the event and the Keck observations allows the planetary host star to be detected at a separation of 66.5±1.7mas from the source star, consistent with the light curve model prediction. The combination of the host star brightness and light curve parameters yield host star and planet masses of M_host = 0.514 ± 0.063M_Sun and m_p = 66.0 ± 8.1M_Earth at a distance of D_L = 7.0 ±0.7kpc. The star-planet projected separation is 2.03 ±0.21AU. The planet-star mass ratio of this system, q = (3.857 ±0.029)×10⁻⁴, places it in the predicted "planet desert" at 10⁻⁴ < q < 4×10⁻⁴ according to the runaway gas accretion scenario of the core accretion theory. Seven of the 30 planets in the Suzuki et al. (2016) sample fall in this mass ratio range, and this is the third with a measured host mass. All three of these host stars have masses of 0.5 ≤ M_host/M_Sun ≤ 0.7, which implies that this predicted mass ratio gap is filled with planets that have host stars within a factor of two of 1M_Sun. This suggests that runaway gas accretion does not play a major role in determining giant planet masses for stars somewhat less massive than the Sun. Our analysis has been accomplished with a modified DAOPHOT code that has been designed to measure the brightness and positions of closely blended stars. This will aid in the development of the primary method that the Nancy Grace Roman Space Telescope mission will use to determine the masses of microlens planets and their hosts.
Code
Repository list and official/mentioned flags are the archive's, frozen 2025-07-28. Reachability, where shown, is from one Syntology probe window (2026-09-16 to 2026-09-18); repositories not probed show nothing. GitHub stars are not tracked.
Code Syntology ran Syntology
Not run by Syntology. Nothing on this page verifies that the listed code works.
Results from the paper archive 2025-07-28
No leaderboard rows for this paper in the archive.
Report a problem or propose a change · a person checks every report against the paper or source before anything changes; decisions are listed on /corrections