Artist's Conception of Gravitational Waves GWIC: Gravitational Wave International Committee


Numerical modelling tools for gravitational wave detectors

The gravitational wave research community has produced a rich set of numerical simulations for the design and test of optical, mechanical and electronic systems used within the detectors. Many of these tools provide a unique set of features not available elsewhere.

This page provides links and contact information for some of this tools with the aim of making these easier to find and more accessible to researchers from other areas and other interested persons.

This page is curated by Andreas Freise; to offer new codes for posting, please contact him. While effort has been made to include only codes which have been checked for errors, the responsibility for each code remains with the contact listed below. GWIC does not warrant any of these codes for their correctness nor for their suitability for any given purpose.

Optical Simulations

Finesse
  • Interferometer simulation program working in the frequency domain using Hermite-Gauss modes. Finesse has been developed within the GEO 600 collaboration and provides a fast and flexible tool for designing and analysing user-defined optical setups. It provides powerful semi-automated methods for investigating effects of beam shape or mirror surface distortions. Additional tools for Finesse are available such as SimTools (utility scripts to use Finesse with Matlab) and Luxor (a Java based GUI for Finesse).
  • Platforms: Linux, Windows, Mac OS X (binary distribution including a detailed, 180 pages strong manual)
  • Written in C, source code available under GPL
  • Contact / Developer: A. Freise
OptoCad
  • The program traces a TEM00 Gaussian beams through an optical setup. OptoCad produces high-quality postscript 2D drawings of the optical components and beams. It is used to provide the well-known optical layout of the GEO 600 detector. OptoCad has a built in interface to Finesse.
  • Platforms: Linux/Unix, Windows, Mac OS X (Fortran source code, install scripts)
  • Written in Fortran, source code available
  • Contact / Developer: R. Schilling
e2e : End to End simulation
  • e2e is a time domain program to simulate opto-mechanical systems. It is based on a modal model. Optical configurations are setup by combining lasers, mirrors, propagators and other devices like modulators and detectors. Mechanical systems and control systems are installed by digital filters or state space models. Digital systems can be implemented by using DAC, ADC and digital filters. The configuration of the simulation setup can be built Alfi, a GUI front end of e2e. Online help is available in Alfi.
  • Platforms: Linux, Mac OS X
  • Simulation engine is written in C++, and GUI is written in Java. Source codes are available.
  • Contact / Developer: Hiroaki Yamamoto
SIS : Stationary Interferometer Simulation
  • SIS is a optical system simulation package. It calculates statics fields and frequency response for test mass motions. The interaction between fields and optics are done in the spatial domain, and the field propagation is done in the frequency domain. The conversion between two domains are done using FFT, hence often called FFT method. The optical system can be locked using the PDH error signal. The package provides many tools to help analyses, like mode expansion of fields which are calculated by FFT methods, automatic inclusion of the Hello-Vinet thermal deformations, and alignment control.
  • Platforms: Linux, Mac OS X
  • Written in C++. Source codes are available.
  • Contact / Developer: Hiroaki Yamamoto
OSCAR
  • OSCAR is a FFT based optical simulation package used to simulate Fabry-Perot cavities or interferometers with realistic optics. The code is written in Matlab, easy to use and is well documented. Typical OSCAR simulations include cavity round trip loss estimations and calculations of steady state fields in interferometers. For the design of Advanced Virgo, OSCAR has been used to find the specifications for the arm cavity mirror flatness and to calculate the loss in sideband power in the recycling cavities. For the 2D simulations of the secondary beams from tilted optics, OSCAR can use a rectangular grid with typically 32 times more points in the direction of the tilt than in the other transverse direction.
  • Platforms: Linux/Unix, Windows, Mac OS X (requires a recent version of Matlab)
  • Written in Matlab, source code available
  • Contact / Developer: J. Degallaix
Optickle
  • Optickle is a frequency domain model for simulating opto-mechanical systems. It is based on a modal model, though only the lowest 3 HG modes are available. Optical configurations are setup by combining lasers, mirrors, propagators and other devices like modulators and detectors. Mechanical systems are represented in terms of their response to radiation pressure. Control system extensions for Optickle are also available:

    • Lentickle adds length control loops to an Optickle plant, for simulating control of opto-mechanical systems. Lentickle eases the selection of sensor, error signals, and control paths necessary for control of complex interferometers.
    • Pickle adds angular control loops to an Optickle plant, for simulating alignment control of opto-mechanical systems. Pickle eases the selection of sensor, error signals, and control paths necessary for alignment control of complex interferometers.

  • Platforms: Matlab 7.12.0 (R2011a) or later
  • Simulation engine is written in Matlab. Source codes are available.
  • Contact / Developer: Matthew Evans
gtrace
  • gtrace is a python package for building and analyzing an optical system using Gaussian beams and optical components such as mirrors and beam splitters. The package was developed to help the optimization of the optical layout of the KAGRA interferometer. However, it should be useful for any optics experiment to track the propagation of Gaussian beams.
  • Platforms: Python 2.6, 2.7
  • Written in Python. Source code available.
  • Contact / Developer: Yoichi Aso