Inner Disk Water Vapor in Protoplanetary Disks with Multiple Gaps

Combining information from protoplanetary disk observations taken at different wavelengths can provide insights into the physical processes occurring in disks. While ALMA observations are sensitive to the dust emission from the outer disk beyond 10 au, which in some disks shows structure in the form of gaps and rings, it is unable to observe the inner most few au. On the contrary, infrared spectroscopy helps us constrain abundances of volatile species (including water vapor) in the innermost disk which are likely brought inwards on icy pebbles from the outer disk that sublimate once they reach the snow line. Banzatti et al. (2020) found from observations that large, structured disks may show lower water vapor abundances than smaller disks, which they argued was likely due to the presence of gaps that trapped icy pebbles in pressure bumps beyond gaps thereby blocking their passage into the inner disk. This link between water vapor abundance and presence of structures in the outer disk was also later supported by modeling in Kalyaan et al. (2021). In this work, we are expanding this model to include multiple gaps, a range of particles sizes, gap locations, and gap strengths to make it comparable with various observed disk structures, to predict water vapor abundances in the innermost regions of such disks. We will be presenting preliminary results from this parameter study.