Coherent X-ray generation in relativistic laser - gas jet interactions

レーザーとガスジェットの相対論的な相互作用におけるコヒーレントX線発生

Pirozhkov, A. S.; 神門 正城; Esirkepov, T. Z.; Gallegos, P.*; Ahmed, H.*; Ragozin, E. N.*; Faenov, A. Ya.*; Pikuz, T.; Koga, J. K.; 桐山 博光; McKenna, P.*; Borghesi, M.*; 近藤 公伯; 大道 博行; 加藤 義章* ; Neely, D.*; Bulanov, S. V.

Pirozhkov, A. S.; Kando, Masaki; Esirkepov, T. Z.; Gallegos, P.*; Ahmed, H.*; Ragozin, E. N.*; Faenov, A. Ya.*; Pikuz, T.; Koga, J. K.; Kiriyama, Hiromitsu; McKenna, P.*; Borghesi, M.*; Kondo, Kiminori; Daido, Hiroyuki; Kato, Yoshiaki*; Neely, D.*; Bulanov, S. V.

We present experimental results, theory, and simulations demonstrating two novel sources of coherent X-ray radiation generated in the relativistic laser ( 10 W/cm) interaction with easily accessible, repetitive, and debris-free gas jet targets. The first source, demonstrated with the 9 TW J-KAREN laser (JAEA), is based on a relativistic mirror reflecting a counter-propagating laser pulse. The second source, demonstrated with the laser power ranging from 9 to 170 TW in experiments with the J-KAREN (JAEA) and Astra Gemini (CLF, RAL) lasers, is based on high order harmonics generation by relativistic-irradiance lasers interacting with underdense plasmas.