Speaker
Hitoshi Sakagami
Description
See the full Abstract at http://ocs.ciemat.es/EPS2018ABS/pdf/P4.2025.pdf
Integrated simulation analysis of core heating property
for ion assisted fast ignition using low-density structured plastic foam
H. Sakagami 1, T. Johzaki 2, A. Sunahara 3, H. Nagatomo 4 and Y. Sentoku 4
1
National Institute for Fusion Science, National Institutes of Natural Sciences, Toki, Japan
2
Hiroshima University, Higashi-hiroshima, Japan
3
Purdue University, West Lafayette, IN, US
4
Institute of Laser Engineering, Osaka University, Osaka, Japan
To mitigate quite low energy coupling from fast electrons to the core, guiding fast
electrons to the core by external magnetic field and improving pulse contrast of the heating
laser are conducted at up-to-date FIREX experiments [1]. To enhance the core heating
moreover, the ion assisted fast ignition scheme [2,3] is also suggested, where low-density
structured plastic (CH) foam is introduced at the bottom of the cone to adapt the radiation
pressure ion acceleration [4].
In recent FIREX experiments, solid ball targets are introduced to stably achieve
compressed dense core instead of shell targets, and this target configuration also enables to
remove the Au cone tip, in which extra energy loss and scattering of fast electrons occur
during propagation. As collisional effects of ions in the cone tip are much larger than those
of electrons, the tipless cone is very useful for ion assisted fast ignition. On the other hand,
a longer pulse of the heating laser is going to be introduced to enlarge the total heating
energy without increasing laser intensity. The longer pulse requires thicker foam to
continuously obtain ion beams, but the stability of ion generation is still unknown for such
long pulses. Thus integrated simulations should be carried out to evaluate core heating
properties for there cases.
*This work is partially supported by JSPS KAKENHI Grant number JP16K05638 and
JP15H05751, and is performed with the support and under the auspices of the NIFS
Collaboration Research program (NIFS17KUGK110 and NIFS12KUGK057).
References
[1] S. Fujioka, et al., Phys. Plasma 23, 056308 (2016).
[2] H. Sakagami, et al., J. Phys.: Conf. Series 688, 012096 (2016).
[3] H. Sakagami, et al., J. Phys.: Conf. Series 717, 012046 (2016).
[4] S. C. Wilks, et al., Phys. Rev. Lett. 69, 1383 (1992).
