312 research outputs found
GRAPE-6: The massively-parallel special-purpose computer for astrophysical particle simulation
In this paper, we describe the architecture and performance of the GRAPE-6
system, a massively-parallel special-purpose computer for astrophysical
-body simulations. GRAPE-6 is the successor of GRAPE-4, which was completed
in 1995 and achieved the theoretical peak speed of 1.08 Tflops. As was the case
with GRAPE-4, the primary application of GRAPE-6 is simulation of collisional
systems, though it can be used for collisionless systems. The main differences
between GRAPE-4 and GRAPE-6 are (a) The processor chip of GRAPE-6 integrates 6
force-calculation pipelines, compared to one pipeline of GRAPE-4 (which needed
3 clock cycles to calculate one interaction), (b) the clock speed is increased
from 32 to 90 MHz, and (c) the total number of processor chips is increased
from 1728 to 2048. These improvements resulted in the peak speed of 64 Tflops.
We also discuss the design of the successor of GRAPE-6.Comment: Accepted for publication in PASJ, scheduled to appear in Vol. 55, No.
High Power Gamma-Ray Flash Generation in Ultra Intense Laser-Plasma Interaction
When high-intensity laser interaction with matter enters the regime of
dominated radiation reaction, the radiation losses open the way for producing
short pulse high power gamma ray flashes. The gamma-ray pulse duration and
divergence are determined by the laser pulse amplitude and by the plasma target
density scale length. On the basis of theoretical analysis and particle-in-cell
simulations with the radiation friction force incorporated, optimal conditions
for generating a gamma-ray flash with a tailored overcritical density target
are found.Comment: 12 pages, 5 figures Accepted for publication in Physical Review
Letters (this http://prl.aps.org/
On extreme field limits in high power laser matter interactions: radiation dominant regimes in high intensity electromagnetic wave interaction with electrons
We discuss the key important regimes of electromagnetic field interaction
with charged particles. Main attention is paid to the nonlinear Thomson/Compton
scattering regime with the radiation friction and quantum electrodynamics
effects taken into account. This process opens a channel of high efficiency
electromagnetic energy conversion into hard electromagnetic radiation in the
form of ultra short high power gamma ray flashes.Comment: 15 pages, 10 figures, invited talk presented at the SPIE-2013
conference, Prague, Czech Republic, Apr. 15, 201
<Abstract of Published Report>Carbonyl Reductase Purified from Rabbit Liver Is Not the Product of a Carbonyl Reductase Gene (RCBR5 or RCBR6)Cloned from the Rabbit Liver cDNA Libray.
<Abstract of Published Report>Catalytic Properties for Naphthoquinones and Partial Primary Structure of Rabbit Heart Acetohexamide Reductase.
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