Center for Computational Sciences, University of Tsukuba
www.ccs.tsukuba.ac.jp
Astrophysical Simulations (2)
Merger of galaxy clusters
In the standard cosmological model, it is believed that
galaxy clusters have experienced multiple mergers of
galaxies and of galaxy groups. Non-equilibrium states
of intracluster plasma are good probes for understanding their formation histories. The FIRST simulator enables us to simulate the dynamical evolution of merging clusters, in parallel with calculations for dozens of
non-equilibrium electron states of oxygen, iron, and
other heavy elements in the plasma.
Density
Temperature
Interaction between Andromeda galaxy and a satellite
Using parallel N-body simulations with 40 million particles, we have studied the interaction between the Andromeda galaxy and its satellite. The simulation nicely
reproduces the giant stellar stream discovered at the
southern part of the Andromeda galaxy. Moreover, the
results show that several of observed faint features in
the Andromeda galaxy can be explained as the forward
continuation of the giant stellar stream.
Phantom-GRAPE
Using the capability of SSE(Streaming SIMD Extensions), a numerical library to accelerate the computation of N-body gravitational forces is developed, which
is named “Phantom GRAPE” after the conventional
GRAPE system, and achieved 18GFLOPS performance on a single core of Core 2 Duo (2.4 GHz) processors.
J-particle
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4 I-particles
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Gravitational Forces on 4 I-particles
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18.3GFLOPS / core is achieved on Core 2 Duo (2.4GHz) processor