[P-PS07] Planetary Sciences

[PPS07-15] Constrains on the properties of forming planets PDS 70 b and c from the dust continuum emission of the circumplanetary disks

*Yuhito Shibaike¹, Christoph Mordasini² (1.Inter-University Research Institute Corporation, National Institutes of Natural Sciences, National Astronomical Observatory of Japan, 2.University of Bern)

Keywords:forming planets, circumplanetary disks, dust continuum emission, gas accretion, dust evolution, protoplanetary disks

Although there have been a lot of theoretical research on the formation of gas planets, observational supports have still been very rare. The young T Tauri star PDS 70 has two gas accreting planets sharing one large gap in a pre-transitional disk, which is a valuable system to obtain observational constraints. Recently, dust continuum emission from PDS 70 c has been detected by Atacama Large Millimeter/submillimeter Array (ALMA) Band 7, which is considered as the evidence of a circumplanetary disk (CPD), a small gas (and dust) disk formed around the planet as a byproduct of the gas accretion. To obtain constraints on the planet properties, we introduce a model of dust evolution in the CPD and reproduce the detection of the dust continuum emission. We find positive correlations between the intensity of the dust emission and three important planet properties, the planet mass, gas accretion rate, and their product called MMdot. From the positive correlations, we then find that the MMdot of PDS 70 c must be larger than 0.4 M_J²/yr, corresponding to the lower limits of the planet mass and the gas accretion rate, 5 M_J and 0.02 M_J/yr. This is the first case to succeed in obtaining constraints on planet properties from the dust continuum emission of a CPD. We also find some loose constraints on the properties of PDS 70 b from the non-detection of its dust emission. We propose possible scenarios for the PDS 70 b and c explaining the non-detection respectively detection of the dust emission from their CPDs.