Refine your search:     
Report No.
 - 
Search Results: Records 1-2 displayed on this page of 2
  • 1

Presentation/Publication Type

Initialising ...

Refine

Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...

Keyword

Initialising ...

Language

Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Save select records

Journal Articles

Laser prepulse dependency of proton-energy distributions in ultraintense laser-foil interactions with an online time-of-flight technique

Yogo, Akifumi; Daido, Hiroyuki; Fukumi, Atsushi*; Li, Z.*; Ogura, Koichi; Sagisaka, Akito; Pirozhkov, A. S.; Nakamura, Shu*; Iwashita, Yoshihisa*; Shirai, Toshiyuki*; et al.

Physics of Plasmas, 14(4), p.043104_1 - 043104_6, 2007/04

 Times Cited Count:63 Percentile:88.17(Physics, Fluids & Plasmas)

Fast protons are observed by a newly-developed $textit{online}$ time-of-flight spectrometer, which provides $textit{shot-to-shot}$ proton-energy distributions immediately after the irradiation of a laser pulse having an intensity of $$sim 10^{18}$$ W/cm$$^2$$ onto a 5-$$mu$$m-thick copper foil. The maximum proton energy is found to increase when the intensity of a fs-prepulse arriving 9 ns before the main pulse increases from 10$$^{14}$$ to 10$$^{15}$$ W/cm$$^2$$. Interferometric measurement indicates that the preformed-plasma expansion at the front surface is smaller than 15 $$mu$$m, which corresponds to the spatial resolution of the diagnostics. This sharp gradient of the plasma makes a beneficial effect on increasing the absorption efficiency of the main-pulse energy, resulting in the increase in the proton energy. This is supported by the result that the X-ray intensity from the laser plasma clearly increases with the prepulse intensity.

Journal Articles

A Simulation on homogeneous isotropic turbulent flows on the earth simulator

Yokokawa, Mitsuo; Saito, Minoru*; Ishihara, Takashi*; Kaneda, Yukio*

Hai Pafomansu Komputingu To Keisan Kagaku Shimpojium (HPCS2002) Rombunshu, p.125 - 131, 2002/01

With the advent of supercomputers, large-scale direct numerical simulations(DNS) of the Navier-Stokes equations are possible to carry out. However, larger scale DNS is required to make turbulence clear and to make a parameterization of turbulence. The Earth Simulator is a distributed memory parallel supercomputer whose peak speed is 40 Tflop/s and it is very useful to make a very large-scale DNS. Simulation codes named ${tt Trans7}$ have been developed for the Earth Simulator and their correctness have been validated by compareing the simulation results by ${tt Trans7}$ with ones by a conventinal code. The sustatined performance of 3.72Gflop/s is obtained in the execution of the serial version with the problem size of $$256^3$$ on an arithmetic processor(AP) of the Earth Simulator. Speedup of about 7 is achieved in 8APs by the parallelized code. Sppedup is degraded by the execution of 8 processor nodes, however, efficiency of 25% against the peak performance is obtained for the problem size of $$512^3$$.

2 (Records 1-2 displayed on this page)
  • 1