Upgrading the LHCb Masterclass Exercise: Measuring the $D^0$ Meson Lifetime

This project upgrades the LHCb Masterclass exercise for measuring the D$^0$ meson lifetime. The old version has been replaced with a modern browser-based application that uses updated 2024 proton–proton collision data from the LHCb detector. The new interface offers improved data visualisation, interactive selection tools, helping students explore how analysis choices affect the measured lifetime. These enhancements make the exercise more modern, accessible, and engaging, giving users an experience closer to real particle physics analysis.