Download our simulations and software.

Simulations and software

Pages containing a repository of Surrey astrophysics simulations and community software:

Code developed by our group members


The binary_c and binary_c-python codes together form a state-of-the-art software framework for the evolution of single and binary stars, nucleosynthesis studies and stellar population calculations. You can download binary_c at its Surrey gitlab page or its mirror. Binary_c-python has its own Surrey gitlab page, a mirror and can be installed with pip3 from its PyPi mirror.

EMACSS (Evolve Me a Cluster of StarS)

EMACSS is a rapid clusters evolution code developed by Poul Alexander (Cambridge) and Mark Gieles. Take a look at the accompanying papers:

LIMEPY (Lowered Isothermal Model Explorer in PYthon)

LIMEPY is a python base code to solve a general class of lowered isothermal model, including Michie (1963) King (1966) and Wilson (1975), including radial anisotropy and multi-mass systems (Gieles and Zocchi, ArXiv 1508.02120)


Libmemoize provides a wrapper around C functions to memoize them, i.e. only call them once for a given set of parameters. If you are running a function which is expensive, gives a unique result result for a given set of input parameters (i.e. is "pure"), then libmemoize may speed up your program. Download from the Surrey git server.


NBODY6tt is an adapted version of Aarseth's NBODY6 (NBODY6 Tidal Tensor) which allows the user defined external potentials to be applied to the cluster. Written by Florent Renaud (Surrey, formerly at Strassbourg and Saclay) and Mark Gieles (Surrey). Read the method papers, this was applied to clusters in merging galaxies and star clusters in dwarf galaxies accreting on the Milky Way.


The librchash library is a C implementation of a hashing library which provides functionality like a Python dict or Perl hash, and can output directly to JSON so its output can directly be implemented in Python or Perl. Download from its Surrey gitlab page.


The librinterpolate library is a very fast linear interpolation library, designed for use in binary_c but useful in its own right. Download from its Surrey gitlab page.

Window to the Stars

Window to the Stars is a graphical user interface to the popular TWIN single/binary stellar evolution code, for novices, students and professional astrophysicists. It removes the drudgery associated with the traditional approach to running the code, while maintaining the power, output quality and flexibility a modern stellar evolutionist requires. It is currently being used for cutting edge research and interactive teaching. Virtualbox image. Window to the Stars is used in the Stars for Schools project.