Interfacing NuSpaceSim's upward air shower modeling with modern detector simulation frameworks.

The NuSpaceSim software simulates tau neutrinos propagating through the Earth, decaying into tau leptons which then produce upward-going air showers in the atmosphere upon Earth's exit. These air showers produce Fluorescence and Cherenkov light that can be detected by both ground- and space-based detectors. In this work, the shower's Cherenkov light is calculated for a given space detector geometry using CHASM (CHerenkov Air Shower Model), and then it is exported to a format readable by the Extreme Universe Space Observatory (EUSO) OffLine simulation and analysis framework, which is used by experiments such as the EUSO Super-Pressure Balloon (EUSO-SPB) missions and the future Probe Of Extreme Multi-Messenger Astrophysics (POEMMA). For the fluorescence light, the NuSpaceSim's shower information is exported following CONEX's format, which is widely used by most modern experiments, such as the Pierre Auger Observatory or the ones aforementioned. Examples of simulated detections by these experiments using NuSpaceSim-generated showers will be shown. Future work includes exposure studies of these experiments to Earth-skimming neutrino-induced air showers.