氮分子{a''^1}\Sigma _g^ (v' = 0)和{a''^1}\Sigma _g^ + (v' = 1) + {b^1}\Pi _u(v' = 0) 广义振子强度的高能电子散射研究
Generalized oscillator strengths of the {a''^1}\Sigma _g^ (v' = 0) and {a''^1}\Sigma _g^ + (v' = 1) + {b^1}\Pi _u(v' = 0) of nitrogen studied by high-energy electron scattering

利用快电子能量损失谱仪结合相对流量技术，在入射电子能量1500 eV和能量分辨70 meV的条件下，测量了氮分子{a''^1}\Sigma _g^ (v' = 0)和{a''^1}\Sigma _g^ + (v' = 1) + {b^1}\Pi _u(v' = 0)激发态的广义振子强度。通过与已有的电子散射结果以及X射线散射结果对比发现，对于{a''^1}\Sigma _g^ (v' = 0)和{a''^1}\Sigma _g^ + (v' = 1) + {b^1}\Pi _u(v' = 0)，我们的结果与X射线散射结果在大动量转移出现差异，这表明对{a''^1}\Sigma _g^ (v' = 0)和{a''^1}\Sigma _g^ (v' = 1)，即使入射电子能量1500 eV也没有达到一阶玻恩近似条件。在动量转移平方小于2 a.u.时， {a''^1}\Sigma _g^ + (v' = 1) + {b^1}\Pi _u(v' = 0)与X射线散射结果的符合表明，对{b^1}\Pi _u(v' = 0)，1500 eV入射电子能量已经达到一阶玻恩近似条件。
The generalized oscillator strengths of {a''^1}\Sigma _g^ (v' = 0) and {a''^1}\Sigma _g^ + (v' = 1) + {b^1}\Pi _u(v' = 0) of molecular nitrogen were measured at a high incident electron energy of 1500 eV and a high energy resolution of 70 meV with the aid of the relative flow technique. It is observed that, the present results are apparently different from the X-ray scattering ones in the large momentum transfer region, which indicates that for {a''^1}\Sigma _g^ (v' = 0) the first-order Born approximation is not satisfied at the incident electron energy E0= 1500 eV in the large momentum transfer region. The agreement of the present results with the X-ray scattering ones for {a''^1}\Sigma _g^ + (v' = 1) + {b^1}\Pi _u(v' = 0) in K2 < 2 a.u. indicates that the first-order Born approximation is satisfied at the incident electron energy E0= 1500 eV for {b^1}\Pi _u(v' = 0).