Pressure broadening and shift of He(2 3P0,1,2) -- He(2 3S) lines
Pressure broadening and shift of He(2 3P0,1,2) -- He(2 3S) lines
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He(2 3P0,1,2) -- He(2 3S)谱线的压力展宽和移动
DOI：
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发表时间：
2004
期刊：
影响因子：
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通讯作者：
H. Sadeghpour
中科院分区：
文献类型：
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作者：
D. Vrinceanu;S. Kotochigova;H. Sadeghpour
在碰撞近似下计算了亚稳态氦原子精细结构谱线的碰撞展宽和位移。用组态相互作用价键方法得到了He（1 1 S 0）和He（2 3 Pj）原子能级的从头算Born-Oppenheimer势能曲线，并结合半经验计算的这些原子之间的货车德瓦耳斯相互作用项研究了j-特异和j-变化碰撞.在He（1 1 S 0）+He（2 3 Pj）极限下的3 Π u势中存在一个长程货车德瓦耳斯势阱，讨论了它对散射相移的影响.在T=310 K时，展宽和位移参数实际上是j独立的，平均值分别为12.60和1.87 MHz/Torr。变j碰撞的横截面大约比特定j碰撞的横截面小五倍。
The collisional broadening and shift of metastable helium fine-structure lines are calculated within the impact approximation. Ab initio Born-Oppenheimer potential energy curves correlating to He(1 1 S 0 ) and He(2 3 P j ) atomic levels are obtained using the configuration interaction valence bond method and combined with semiempirically calculated van der Waals interaction terms between these atoms to also study j-specific and j-changing collisions. A long-range van der Waals potential well exists in the 3 Π u potential correlated to the He(1 1 S 0 )+He(2 3 P j ) limit, whose influence on the scattering phase shift is assessed. At T=310 K, the broadening and shift parameters are practically j independent and have average values of 12.60 and 1.87 MHz/Torr, respectively. The j-changing collisions have cross sections roughly five times smaller than the j-specific cross sections.