High energy electrons and x-ray photons emitted by water plasmas produced by femtosecond laser pulses

【Author】 Y. T. Li, J. Zhang, Z. M. Sheng, H.Teng, T. J. Liang, X. Y. Peng, X. Lu, Y. J. Li, X. W. TangLaboratory of Optical Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, P. R. ChinaInsitute of High Energy Physics, Chinese Academy of Sciences, Beijing 100039, P. R. China

【摘要】 <正>Hot electrons and x-ray photons emitted by water plasmas produced by single and multiple laser pulses are investigated. For the same pulse energy of 5 mJ in our experiments, the multipulse mode greatly enhances the generation of hot electrons. The hot-electron temperature is about 64 keV, and electrons with energies higher than 25 keV are emitted in two directions symmetrically at 46?from the direction of the laser electric field and in the polarization plane. Two-dimensional particle-in-cell simulations reproduce well the experimental results and indicate that the acceleration mechanism of hot electrons is mainly due to the resonance absorption at the edge of the spherical droplets formed by leading pulses.更多还原

【Abstract】 Hot electrons and x-ray photons emitted by water plasmas produced by single and multiple laser pulses are investigated. For the same pulse energy of 5 mJ in our experiments, the multipulse mode greatly enhances the generation of hot electrons. The hot-electron temperature is about 64 keV, and electrons with energies higher than 25 keV are emitted in two directions symmetrically at 46° from the direction of the laser electric field and in the polarization plane. Two-dimensional panicle-in-cell simulations reproduce well the experimental results and indicate that the acceleration mechanism of hot electrons is mainly due to the resonance absorption at the edge of the spherical droplets formed by leading pulses.更多还原