RAyMOND: An N-body and hydrodynamics code for MOND
  The LCDM concordance cosmological model is supported by a wealth of
observational evidence, particularly on large scales. At galactic scales,
however, the model is poorly constrained and recent observations suggest a more
complex behaviour in the dark sector than may be accommodated by a single cold
dark matter component. Furthermore, a modification of the gravitational force
in the very weak field regime may account for at least some of the
phenomenology of dark matter. A well-known example of such an approach is
MOdified Newtonian Dynamics (MOND). While this idea has proven remarkably
successful in the context of stellar dynamics in individual galaxies, the
effects of such a modification of gravity on galaxy interactions and
environmental processes deserves further study. To explore this arena we modify
the parallel adaptive mesh refinement code RAMSES to use two formulations of
MOND. We implement both the fully non-linear aquadratic Lagrangian (AQUAL)
formulation as well as the simpler quasi-linear formulation (QUMOND). The
relevant modifications necessary for the Poisson solver in RAMSES are discussed
in detail. Using idealised tests, in both serial and parallel runs, we
demonstrate the effectiveness of the code.
