CorrSim: A Multiwavelength Timing Observation Simulator

Studying the rapid variability of many astronomical objects is key to understanding the underlying processes at play. However, a combination of limited telescope availability, viewing constraints, and the unpredictable nature of many sources mean that obtaining data well-suited to this task can be tricky, especially when it comes to simultaneous multiwavelength observations. Researchers can often find themselves tuning observational parameters in real-time, or may realise later that their observation did not achieve their goals. Here, we present CorrSim, a program to aid planning of multiwavelength coordinated observations. CorrSim takes a model of a system (i.e. Power Spectra, Coherence, and Lags), and returns a simulated multiwavelength observation, including effects of noise, telescope parameters, and finite sampling. The goals of this are: (i) To simulate a potential observation (to inform decisions about its feasibility); (ii) To investigate how different Fourier models affect a system's variability (e.g. how altering the frequency-dependent lags between bands can affect data products like cross-correlation functions); and (iii) To simulate existing data and investigate its trustworthiness. We outline the methodology behind CorrSim, show how a variety of parameters (e.g. noise sources, observation length, and telescope choice) can affect data, and present examples of the software in action.