Improving Detection of Inclined Cosmic-Ray Air Showers at the IceCube Neutrino Observatory

The IceCube Neutrino Observatory, located at the South Pole, consists of a one cubic-kilometer in-ice detector and a one square-kilometer surface array for cosmic-ray air showers named IceTop. IceTop starts measuring showers below ~1 PeV and covers the complete energy range of the galactic-to-extragalactic source transition, spanning below the first knee to the second knee of the cosmic-ray spectrum. To increase acceptance of inclined cosmic-ray air shower events at the observatory, the IceTop7HG trigger was developed. Implemented in the 2023 data run season, the trigger has a higher efficiency of capturing inclined air showers compared to standard triggers. Additionally, these events can provide the basis for higher statistics measurements with radio antenna and scintillator panels that are part of an ongoing enhancement of the surface array. To reduce low-energy event background and bring in events from the IceTop7HG for further analysis, an event selection filter for the trigger is under development. Impacts of event parameters on the filter’s performance and selection criteria will be discussed.