Kinetic-energy release in CO dissociation caused by fast F4+ impact.
Kinetic-energy release in CO dissociation caused by fast F4+ impact.
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DOI：
10.1103/physreva.51.391
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发表时间：
1995
期刊：
影响因子：
--
通讯作者：
Ben-Itzhak;Ginther;Krishnamurthi;Carnes
中科院分区：
文献类型：
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作者：
Ben-Itzhak;Ginther;Krishnamurthi;Carnes
用符合飞行时间技术研究了1 MeV/amuF [sup 4+]碰撞引起的CO解离。在CO[sup [ital Q]+]分解成离子对C[sup [ital q]][sub 1]+和[ital O][sup [ital q]][sub 2][sup +]的过程中释放的动能由两个带电碎片的飞行时间的测量差确定。比较了不同撞击物作用下CO[sup 2+]解离成C[sup +]和O[sup +]的动能分布。随着相互作用强度的增加，这些分布向更高的动能释放值转移。一个单一的高斯动能分布是在良好的协议与高电荷的CO解离，而双和三重电荷的CO，需要额外的高斯。虽然库仑爆炸模型近似地预测了测量分布的最可能值，但所有分布的宽度都被模型严重低估了。测量的分布宽度只能通过调用多电荷离子的势能曲线的存在来解释，与库仑曲线相比，势能曲线具有更陡和更浅的斜率。用反射方法计算了F[sup 4+]+CO[r arrow]CO[sup 2+*]跃迁到所有已知CO[supmore » 2+]态的动能释放.然后将最终的动能分布拟合到数据中，以评估不同转变的权重。计算出的拟合与测量值相当一致，尽管无法解释测量分布的高能尾部，这表明需要包括来自高激发解离态或曲线交叉的贡献。«少
The dissociation of CO caused by 1-MeV/amu F[sup 4+] impact has been studied using the coincidence time-of-flight technique. The kinetic energy released during the dissociation of CO[sup [ital Q]+] into ion pairs C[sup [ital q]][sub 1]+ and [ital O][sup [ital q]][sub 2][sup +] was determined from the measured difference in the times of flight of the two charged fragments. The kinetic-energy distributions of CO[sup 2+] dissociating into C[sup +] and O[sup +] as a result of different impinging projectiles have been compared. These distributions shift towards higher kinetic-energy release values with increasing strength of interaction. A single Gaussian kinetic-energy distribution is in good agreement with the highly charged CO dissociation, while for doubly and triply charged CO, additional Gaussians are needed. While the Coulomb-explosion model approximately predicts the most likely value of a measured distribution, the widths of all distributions are grossly underestimated by the model. The measured widths of the distributions can be explained only by invoking the existence of potential-energy curves of the multiply charged ions that have steeper and shallower slopes as compared to the Coulombic curve. The reflection method was used to calculate the kinetic-energy release for F[sup 4+]+CO[r arrow]CO[sup 2+*] transitions to all known CO[supmore » 2+] states. The final kinetic-energy distribution was then fitted to the data in order to evaluate the weights of the different transitions. The calculated fit is in fair agreement with the measured one, although the high-energy tail of the measured distribution could not be accounted for, indicating that contributions from highly excited dissociating states or from curve crossings need to be included.« less