Optical emission from Al target irradiated by FLASH

Plasma Physics by Laser and Applications 2013 Conference

Stránský, M.^1 ; Rohlena, K.^1

Institute of Physics, Na Slovance 2, Prague 8-Libe, 182 21, Czech Republic^1

关键词: 13.5 nm;    Aluminum target;    Fs pulse;    Lower density;    Neutral atoms;    Optical emissions;    Optical spectrometers;    Plasma plumes;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/508/1/012008/pdf
DOI  :  10.1088/1742-6596/508/1/012008

来源: IOP

【 摘 要 】

The following text touches on some peculiarities in optical emission spectroscopy results from experiments on the free-electron laser FLASH [1, 2]. Aluminum targets were irradiated with 13.5 nm ∼ 25 fs pulses at intensities of 1013and 1016W/cm2(20 and 1 μm foci). Surprisingly, only neutral atom lines for the case with wider focus and traces of ion lines in the tighter focus case were observed with the optical emission spectroscopy (200-600 nm range), [2]. The motivating idea behind this work is the suggestion in [1] by Zastrau that the optical spectrometer sees only emissions from a cold expanding lower-density (22cm-3) plasma plume. In this contribution the notion of UV range screening is analyzed in detail.