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Searching for codes credited to 'Couchman, Hugh'

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[ascl:1103.010] Hydra: A Parallel Adaptive Grid Code

We describe the first parallel implementation of an adaptive particle-particle, particle-mesh code with smoothed particle hydrodynamics. Parallelisation of the serial code, "Hydra," is achieved by using CRAFT, a Cray proprietary language which allows rapid implementation of a serial code on a parallel machine by allowing global addressing of distributed memory.

The collisionless variant of the code has already completed several 16.8 million particle cosmological simulations on a 128 processor Cray T3D whilst the full hydrodynamic code has completed several 4.2 million particle combined gas and dark matter runs. The efficiency of the code now allows parameter-space explorations to be performed routinely using $64^3$ particles of each species. A complete run including gas cooling, from high redshift to the present epoch requires approximately 10 hours on 64 processors.

[ascl:1103.011] AP3M: Adaptive Particle-particle, Particle-mesh Code

AP3M is an adaptive particle-particle, particle-mesh code. It is older than Hydra (ascl:1103.010) but faster and more memory-efficient for dark-matter only calculations. The Adaptive P3M technique (AP3M) is built around the standard P3M algorithm. AP3M produces fully equivalent forces to P3M but represents a more efficient implementation of the force splitting idea of P3M. The AP3M program may be used in any of the three modes with an appropriate choice of input parameter.