I am an undergraduate working in my university's high energy physics lab. I'm still new to particle physics, so I have to learn/understand a bunch of things on the fly. We are currently searching for a new state theorized to occur in a specific decay process. I know we have to work with data only on the initial and final states, since we know nothing about intermediate states (they are not physical observables). I'm not too sure about the reconstruction process, but I will likely understand that better once I understand the following questions... My questions are regarding about the purpose of Monte Carlo simulations. Why is it necessary to run these simulations before analyzing the real data? What exactly does a Monte Carlo simulation tell us? How might a simulation help in searching for a new state? I know these questions are fairly broad, so apologies in advance. If I didn't provide enough context or just generally didn't provide enough information, let me know and I'll try my best to make things clear. I looked through other threads about similar topics but didn't find them to be too satisfying. I'd like to get a handle on this as soon as possible, so any insight would be beneficial!