End to End Simulation Program for Gravitational-Wave Detectors

Within the LIGO project, a time domain simulation program has been developed to provide an accurate description of gravitational wave detectors that use laser interferometry. The program simulates the time evolution of fields, optics, mechanical structures and control systems. The program is written in C++ and the modular design of this program makes it possible to simulate a wide variety of processes without modifying the program. This design also makes it easy to add new functionality. Using a graphical user interface (GUI), one can easily set up or modify the system to be simulated. The underlying physics and the structure of this simulation package are described in this paper.