A Pan-STARRS Search for Distant Planets

We present a search for distant planets in Pan-STARRS1. We calibrated our search by injecting an isotropic control population of synthetic detections into Pan-STARRS1 source catalogs, providing a high-fidelity approximation to injecting synthetic sources at the image level. We found that our method is sensitive to a wide range of distances, as well as all rates and directions of motion. We recovered 692 solar system objects, including 642 TNOs, 23 of which are dwarf planets. By raw number of detections, this makes our search the third most productive Kuiper Belt survey to date, in spite of the fact that we did not explicitly search for objects closer than 80 au. Although we did not find Planet Nine or any other planetary objects, we were able to show that the remaining parameter space for Planet Nine is highly concentrated in the galactic plane. We are in the process of extending our search to interior to 80 au. The lessons learned in our search are directly applicable to upcoming searches with data from the Vera C. Rubin Observatory's Legacy Survey of Space and Time.