Shallow Cavities in Multiple-Planet Systems

Abstract

Large cavities are often observed in protoplanetary disks, which might suggest the presence of planets opening gaps in the disk. Multiple planets are necessary to produce a wide cavity in the gas. However, multiple planets may also be a burden to the carving out of very deep gaps. When additional planets are added to the system, the time-dependent perturbations from these additional satellites can stir up gas in the gap, suppressing cavity opening. In this study, we perform two-dimensional numerical hydro calculations of gap opening for single and multiple planets, showing the effect that additional planets have on the gap depths. We show that multiple planets produce much shallower cavities than single planets, so that more massive planets are needed in the multiple-planet case to produce an equivalent gap depth as in the single-planet case. To deplete a gap by a factor of 100 for the parameters chosen in this study, one only requires $M_p\approx 3.5M_J$ in the single-planet case, but much more massive planets, $M_p\approx 7M_J$ are required in the multiple-planet case. This requirement of high-mass planets implies that such planets may be detectable in the next generation of direct imaging projects, in gaps whose depths are constrained to be sufficiently deep by ALMA.

ApJ Accepted

References in corpus (6)

• On the Diversity of the Taurus Transitional Disks: UX Tau A & Lk Ca 15
• Discovery of a Companion Candidate in the HD169142 Transition Disk and the Possibility of Multiple Planet Formation
• Subaru Imaging of Asymmetric Features in a Transitional Disk in Upper Scorpius
• CO gas inside the protoplanetary disk cavity in HD 142527: disk structure from ALMA
• NIR Spectroscopy of the HAeBe Star HD 100546: III. Further Evidence of an Orbiting Companion?
• Comparison of the dust and gas radial structure in the transition disk [PZ99] J160421.7-213028