24P165-B
Quasi-one-dimensional Target by using Intense Ion Beams
toward High Energy Density Astrophysics
大強度イオンビームを利用した高エネルギー密度宇宙物理実験のための	 準1次元標的の実現
Toru Sasaki, Takashi Kikuchi, Nob. Harada, Kazuhiko Horioka1), and Nagatomo Hideo2)
佐々木徹, 菊池崇志，原田信弘，堀岡一彦1)，長友英夫2)Department of Electrical Engineering, Nagaoka University of Technology
Kamitomioka 1603-1, Nagaoka, Niigata 940-2188, Japan
長岡技術科学大学 〒940-2188	  新潟県長岡市上富岡町1603-1
1)

Department of Energy Sciences, Tokyo Institute of Technology
Nagatsuta 4259, Midori-ku, Yokohama, 226-8502, Japan1) 東京工業大学 〒226-8502	  神奈川県横浜市緑区長津田町42591)

Institute for Laser Engineering, Osaka University
Yamadaoka 2-6, Suita, Osaka, 565-0871, Japan2) 大阪大学レーザーエネルギー学研究センター 〒565-0871	  大阪府吹田市山田丘2-6
We proposed HED experiment based on intense ion beams as possible parameters of KEK digital
accelerator. New target plasma, which was point-spot like spherical radiation source, was generated by theprogramed intense ion beams. We also investigated the radiation hydrodynamics based on the intense ionbeams. To generate the well-defined plasma, we calculated the spherical target using intense ion beamswith 1 mm in radius. The results indicated that the spherical target plasma could be point-spot like
temperature distribution and the target size was about 0.4 mm full width of half maximum.

1. Introduction
High energy density physics (HEDP) is ofinterest in the efficient implosion of the inertial
confinement fusion, the originating Solar Systems
evaluated by the interior of giant planets as theJupiter and the Saturn, and the generating processof highly energetic particles in astrophysicalphenomena as the Gamma-ray burst, and so on[1]. Understanding these behavior and/orstructure, we should have exact data on theequation of state (EOS) and the transport
properties of electron and radiation in highenergy density (HED) state. HED state of matter,
which is categorized as a warm dense matter(WDM), a hot dense matter (HDM), and aradiation dominated matter (RDM), has apotential of abundant scientific discovery
including the properties of plasma [2].
Intense ion beams, which are provided by theinduction systems, are opening up an attractive
branch for HEDP [3-10] Accelerators producing
opportunely tailored energies of intense ion beams
are promising energy drivers for inertial fusionenergy and are also expected to be able to provide a
useful tool for creating HED matters. Compared tothe high power devices, the intense ion beams using
induction technology [11] have many advantages;

in uniformity of energy deposition, in large volumeof the samples compared to diagnostic resolution, invirtue of the long stopping range, in anadvantageous environment for diagnostics, in an
ability to heat a variety of target materials in acondition with high repetition rate and multiple
beam lines.
For the HEDP study based on the ion beams
irradiation, the target should be in equilibrium andas well-defined as possible to accurately diagnose
the physical parameters. In this study, we propose amethod to make a HED state of matter based on
available beam parameters in KEK digital
accelerator. In this paper, a spherical point-spot likeradiator is discussed using intense ion beams.
2. Quasi-spherical plasma for radiationhydrodynamics experiments based on intense ionbeams
The hydrodynamics dominated by radiative
energy flux and pressure plays a crucial role in not
only for exploring astrophysical phenomena but
also for evaluating the efficiency of hohlraum target
for ICF driven by HIBs or lasers [1,12]. Especially,
the explosion process in supernova is strongly
affected by the radiation transfer in a wide range ofparameters from optical thick to thin condition.

2101r[mm](a) Initial Condition

206
Temperature[eV](b) 5 ns

12012.525
Temperature[eV](c) 10 ns017.5
35
Temperature[eV](d) 20 ns

Fig. 1 Time evolution of spherical target irradiated by Argon ion beams with 2 × 1013 per bunch.

Then, we cannot determine directly the origin ofradiation from the astronomical observation due tothe unclarified effects. In order to study suchprocesses, we should evaluate the energy transfer indense high temperature matter. In a region from
HDM to RDM, we should consider both thehydrodynamic energy flux and the radiation flux.
The focusing beams as KEK Digital Accelerator
with PS-ring are able to produced both HDM andRDM conditions [2].
We calculated the hydrodynamics of target with
two-dimensional spherical geometry, which isassumed aluminum solid target with 1 mm in radius.
The detail of calculation is shown in Ref. [10]. In
this calculation, the beam radius is set to be 1~mmwith a Gaussian distribution. The beam duration is
100 ns, and the beam particle number is 2x1013
argon ions with monotonic particle energy (1.67GeV), which is considered to the stopping range inthe target.
Figure 1 shows preliminary results of theevolutions of temperature at each time. As shown inFig. 1, the point-spot like temperature distribution
can be generated by the light ion beams. The radiusof generated point-spot plasma is 0.4 mm full widthof half maximum at center of target. It might
indicated that the more smaller spherical plasma iscreated by irradiation of smaller beam radius.
3. Summary
We proposed HED experiment based on intense
ion beams as possible parameters of KEK digital
accelerator. New target plasma, which waspoint-spot like spherical radiation source, wasgenerated by the programed intense ion beams. We
also investigated the radiation hydrodynamics basedon the intense ion beams. To generate thewell-defined plasma, we calculated the sphericaltarget using intense ion beams with 1 mm in radius.
The results indicated that the spherical target
plasma could be point-spot like temperature

distribution and the target size was about 0.4 mm
full width of half maximum.
References[1] R. P. Drake, “High-Energy-Density Physics,Fundamentals, Inertial Fusion, and Experimental
Astrophysics”, Springer (2005).
[2] T. Sasaki, et. al., Journal of Plasma and Fusion
Research SERIES, 8, p. 174 (2009).
[3] E. Dewald, et. al., Laser and Particle Beams, 20, p.
399 (2002)[4] A. Kozyreva, et. al., Phys. Rev. E, 68, p. 056406(2003).
[5] L. R. Grisham, Phys. Plasmas, 11, pp. 5727 (2004).
[6] N. A. Tahir, et. al., Phys. Rev. E, 63, p. 016402(2001).
[7] N. A. Tahir, et. al., Phys. Rev. Lett., 95, p. 035001(2005).
[8] J. J. Barnard, et. al., NIM A, 577, p. 275 (2007).
[9] J. J. Barnard, et. al., NIM A, 606, p. 134 (2009).
[10] T. Sasaki, et. al., NIM A, 606, p. 161 (2009).
[11] K. Takayama, et. al., Phys. Rev. Lett., 98, p. 054801(2007).
[12] J. I. Castor, “Radiation Hydrodynamics”.
Cambridge University Press, (2004).