Poster Abstracts

Name/Affiliation:  Emily Drabek-Maunder (Imperial College London)

Title:  HCO+ in LkCa 15 transitional disk

LkCa 15 is an extensively studied star in the Taurus molecular cloud known for its transitional disk. This disk is observed to have a large cavity in dust continuum emission with a normal gas accretion rate onto the central star. Gaps in transitional disks have been proposed to result from the interaction of multiple planets forming in the disk, but there are currently few observations available to support this claim. If multiple planets do create these observed cavities, it is possible the gas would flow across the gap to accrete onto the star with relatively little accretion onto the planets themselves. We present single-spectrum HCO+ J=4-3 observations of the LkCa 15 transitional disk from the JCMT. We will further investigate the process of accretion in the system by estimating the amount of gas that is present in the disk cavity. This allows us to distinguish between two possible driving scenarios for the starís high accretion rate, including high surface-density gas flowing at slower radial velocities or low surface-density gas moving at high velocities (potentially by means of streamers).†