论文类型：
期刊论文
第一作者：
Wu, Ding
通讯作者：
Ding, HB (reprint author), Dalian Univ Technol, Chinese Minist Educ, Sch Phys, Key Lab Mat Modificat Laser Ion & Electron Beams, Dalian 116024, Peoples R China.
合写作者：
Sun, Liying,Liu, Jiamin,Yu, Xiao,Hai, Ran,Feng, Chunlei,Wang, Zhiwei,Ding, Hongbin
发表时间：
2019-01-01
发表刊物：
PHYSICS OF PLASMAS
收录刊物：
SCIE、EI、Scopus
文献类型：
J
卷号：
26
期号：
1
ISSN号：
1070-664X
关键字：
Ablation; Atom lasers; Electrons; Flight dynamics; Ionization of gases; Ions; Kinetic energy; Kinetics; Laser ablation; Laser produced plasmas; Light emission; Neodymium lasers; Plasma sheaths; Tungsten; Yttrium aluminum garnet, Ambient atmosphere; Continuum radiation; Laser induced plasma; Laser pulse duration; Nanosecond laser ablation; Plasma properties; Time resolved optical emission spectroscopy; Transient dynamics, Optical emission spectroscopy
摘要：
A Nd:YAG laser with a power density of 15GW/cm(2), operating at a wavelength of 1064 nm, was used to ablate a tungsten (W) target placed in an ambient atmosphere of air at a pressure of 10 mbar. A systematic study of plasma properties employing fast photography and time and space resolved optical emission spectroscopy was carried out. The results showed that there were continuum, neutral, and singly ionized W atom optical emission in the laser-induced plasma; the spectra of ambient gas N-2 and N-2(+) were aslo observed which appeared at very early times (< 30 ns). The spectra of N-2(+) presented a temporal profile with a narrow width (similar to 20 ns) and a steep rising edge (similar to 10 ns) that was very close to the laser pulse duration, which revealed that the prompt electrons ejected from theW target collisionally excited and ionized ambient N-2 gas molecules. The approximate timescales from nanoseconds to microseconds of four laser-produced W plasma processes including prompt electrons, continuum radiation, ions, and neutral emission were given according to time-resolved optical emission spectroscopy. Fast imaging showed that the prompt electrons were expanding hemispherically. The optical time of flight dynamics of N-2(+) corresponding to the prompt electrons at different positions showed that the kinetic energy of prompt electrons was up to 22 eV. These prompt electrons with high energy result in the separation from the core plasma which indicated the existence of the transient dynamic plasma sheath during the laser ablation process and interpreted the acceleration of ions. Published under license by AIP Publishing.
是否译文：
否
