Charge transfer and ionisation by intermediate-energy heavy ions.
Charge transfer and ionisation by intermediate-energy heavy ions.
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中等能量重离子的电荷转移和电离。
DOI：
10.1093/rpd/ncl450
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发表时间：
2006
影响因子：
1
通讯作者：
Reinhold,CO
中科院分区：
文献类型：
--
作者：
Toburen,LH;McLawhorn,SL;McLawhorn,RA;Evans,NL;Justiniano,ELB;Shinpaugh,JL;Schultz,DR;Reinhold,CO
使用重离子束的哺乳动物细胞反应的微束研究导致需要更好地了解重离子与组织成分的碰撞的相互作用截面。对于几MeV u− 1或更小的离子能量，离子从它们行进的介质中捕获电子，并作为部分“修饰”离子进行后续相互作用。例如，16 MeV的氟离子的平衡电荷为7+，32 MeV的硫离子的平衡电荷为11+，并且随着离子能量的降低，平衡电荷急剧降低。部分修饰离子相互作用的数据非常罕见，因此很难估计导致细胞成分损伤的能量沉积的微观模式。这样的估计，通常通过蒙特卡罗轨道结构模拟获得，需要一个全面的数据库的微分和总电离截面以及电荷转移截面。为了提供信息的轨道模拟，测量总电离截面已开始在东卡罗莱纳大学使用反冲离子飞行时间的方法，也产生多个电离过程和电荷转移截面的截面;多电离是普遍的重离子相互作用。此外，正在进行电离微分截面的测量，以便用蒙特卡罗模拟详细的逐事件粒子轨迹。描述了能量为100和200 keV u− 1的C+离子的微分、总和多重电离截面以及电子捕获和损失截面。
The use of heavy ion beams for microbeam studies of mammalian cell response leads to a need to better understand interaction cross sections for collisions of heavy ions with tissue constituents. For ion energies of a few MeV u−1or less, ions capture electrons from the media in which they travel and undergo subsequent interactions as partially ‘dressed’ ions. For example, 16 MeV fluorine ions have an equilibrium charge of 7+, 32 MeV sulphur ions have an equilibrium charge of ∼11+, and as the ion energies decrease the equilibrium charge decreases dramatically. Data for interactions of partially dressed ions are extremely rare, making it difficult to estimate microscopic patterns of energy deposition leading to damage to cellular components. Such estimates, normally obtained by Monte Carlo track structure simulations, require a comprehensive database of differential and total ionisation cross sections as well as charge transfer cross sections. To provide information for track simulation, measurement of total ionisation cross sections have been initiated at East Carolina University using the recoil ion time-of-flight method that also yields cross sections for multiple ionisation processes and charge transfer cross sections; multiple ionisation is prevalent for heavy ion interactions. In addition, measurements of differential ionisation cross sections needed for Monte Carlo simulation of detailed event-by-event particle tracks are under way. Differential, total and multiple ionisation cross sections and electron capture and loss cross sections measured for C+ions with energies of 100 and 200 keV u−1are described.