Development of a Two-Component Lateral Distribution Function to Reconstruct the Muon Content in Air Showers Measured with IceTop

Located 1.5 kilometers beneath the ice at the geographic south pole, the IceCube Neutrino Observatory detects astrophysical neutrinos that permeate the Antarctic ice. The in-ice detector is complemented by a surface array, IceTop, that consists of 81 detector stations used to measure the low energy content of cosmic ray-initiated extensive air showers (EAS). By fitting two lateral distribution functions (LDF) to the tank signals measured in IceTop we can evaluate the primary energy and muon content of EAS on an event-by-event basis.

This work describes the development of a muon LDF event reconstruction for use in IceTop. Optimizations include the injection of additional muon information in the fit procedure as well as the incorporation of in-ice information for coincident events. The performance of the reconstruction pre- and post-optimization for event geometry, energy reconstruction, and muon number reconstruction is presented.