Enhanced plasma heating via interaction with high-contrast laser and cone-shaped target

Yuga Karaki; Yoshitaka Mori; Eigo Ebisawa; Yuichi Inubushi; Sadaoki Kojima; Kohei Yamanoi; Yuki Abe; Takumi Tsuido; Hiroki Matsubara; Rinya Akematsu; Ryo Omura; Ryunosuke Takizawa; King Fai Farley Law; Eisuke Miura; Yasunobu Arikawa; Keisuke Shigemori; Akifumi Iwamoto; Katsuhiro Ishii; Ryohei Hanayama; Yoneyoshi Kitagawa; Hiroshi Sawada; Takayoshi Sano; Natsumi Iwata; Yasuhiko Sentoku; Atsushi Sunahara; Tomoyuki Johzaki; Kenichi Nagaoka; Shinsuke Fujioka

arXiv · 2506.06963

Enhanced plasma heating via interaction with high-contrast laser and cone-shaped target

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Abstract

We investigated plasma heating enhancement using a high-intensity, high-contrast laser and a cone-attached target. Fast electron spectra and X-ray emission were measured with an electron spectrometer and a Bragg crystal spectrometer. The results were analyzed using PrismSPECT simulations with a two-component electron distribution model and empirical scaling laws. X-ray pinhole images showed that the cone effectively focused multi-spot laser light near its tip, enhancing local emission. While high-contrast laser irradiation reduced the fast electron slope temperature for flat targets, the use of a cone increased it by over threefold, corresponding to a fourfold rise in laser intensity. X-ray spectral analysis indicated an electron temperature of ~9~keV for the cone case, 17.5 times higher than that with a low-contrast laser. These findings demonstrate that combining high-contrast laser irradiation with cone-target geometry significantly improves laser energy coupling and plasma heating efficiency.

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Yuga Karaki, Yoshitaka Mori, Eigo Ebisawa, Yuichi Inubushi, Sadaoki Kojima, Kohei Yamanoi, Yuki Abe, Takumi Tsuido, Hiroki Matsubara, Rinya Akematsu, Ryo Omura, Ryunosuke Takizawa, King Fai Farley Law, Eisuke Miura, Yasunobu Arikawa, Keisuke Shigemori, Akifumi Iwamoto, Katsuhiro Ishii, Ryohei Hanayama, Yoneyoshi Kitagawa, Hiroshi Sawada, Takayoshi Sano, Natsumi Iwata, Yasuhiko Sentoku, Atsushi Sunahara, Tomoyuki Johzaki, Kenichi Nagaoka, Shinsuke Fujioka. 2025-06-08. Enhanced plasma heating via interaction with high-contrast laser and cone-shaped target. https://arxiv.org/abs/2506.06963

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