Abstract The values of direct double- to-single ionization ratio $R$ of helium atoms induced by C$^{q + }$, O$^{q + }$ ($q=1-4$) ions at incident energies from 0.2 to 8.5MeV are measured. Based on the existing model (Shao J X, Chen X M and Ding B W 2007 Phys. Rev. A 75 012701) the effective charge of the projectile is introduced to theoretically estimate the value of $R$ for the partially stripped ions impacting on helium atoms. The results calculated from our ``effective charge'' model are in good agreement with the experimental data, and the dependence of the effective charge on the ionization energy of the projectile is also discussed qualitatively.
Received: 04 May 2008
Revised: 16 May 2008
Accepted manuscript online:
(General theories and models of atomic and molecular collisions and interactions (including statistical theories, transition state, stochastic and trajectory models, etc.))
Fund: Project supported by the National
Natural Science Foundation of China (Grant No 10775063).
Cite this article:
Zhou Chun-Lin (周春林), Shao Jian-Xiong (邵剑雄), Chen Xi-Meng (陈熙萌), Sun Guang-Zhi (孙光智), Zou Xian-Rong (邹贤容) The direct ionization processes in the collisions of partially stripped carbon and oxygen ions with helium atoms at low-to-intermediate energies 2008 Chin. Phys. B 17 4193
Single-and-double electron loss of O2+ in collisions with argon and helium Liu Yu-Wen(刘玉文), Chen Xi-Meng(陈熙萌), Lu Yan-Xia(鲁彦霞), Ding Bao-Wei(丁宝卫), Fu Hong-Bin(付宏斌), Gao Zhi-Min(高志民), Cui Ying(崔莹), Shao Jian-Xiong(邵剑雄), Sun Guang-Zhi(孙光智), Chen Lin(陈林), and Yin Yong-Zhi(尹永智). Chin. Phys. B, 2008, 17(7): 2590-2593.
Altmetric calculates a score based on the online attention an article receives. Each coloured thread in the circle represents a different type of online attention. The number in the centre is the Altmetric score. Social media and mainstream news media are the main sources that calculate the score. Reference managers such as Mendeley are also tracked but do not contribute to the score. Older articles often score higher because they have had more time to get noticed. To account for this, Altmetric has included the context data for other articles of a similar age.