高电荷态离子129Xe29+与不同金属表面作用产生的X射线谱

研究了高电荷态离子129Xe29+入射金属Au、Mo、Be表面产生的特征X射线谱。实验结果表明,在入射离子的动能相同时,Au的Mα1-X射线产额比Mo的Lα1-X、Lα2-X、Lβ 1-X射线总产额高,特征X射线的产额随入射离子动能的增加而显著增加;不同动能的Xe29+入射金属Au、Mo、Be表面均未产生Xe的特征X射线。     

高电荷态离子129Xe28+与Au和Mo表面作用产生的X射线谱

研究了高电荷态离子129Xe28+轰击金属Au和Mo表面产生的特征X射线谱.实验结果表明,在入射离子的电荷态和能量相同的条件下,对于核电荷数较小、原子质量较轻的靶原子,只有其内壳层的电子才能被激发而产生X射线,而核电荷数较大、原子质量较重的靶原子只有其较外壳层的电子能被激发而产生X射线.特征X射线的产额随入射离子动能的增加而增加.     

高电荷态离子Arq+与不同金属靶作用产生的X射线

研究了高电荷态离子Arq+(q=16,17,18)入射金属Be,Al,Ni,Mo,Au靶表面产生的X射线谱.实验结果表明,Ar的Kα-X射线是离子在与固体表面相互作用过程中固体表面之下形成空心原子发射的.电子组态1s2的高电荷态Ar16+离子在金属表面中性化过程中,存在的多电子激发过程使Ar16+的K壳层电子激发产生空穴,级联退激发射Ar的Kα特征X射线.Ar17+离子在金属表面作用过程中产生的X射线谱形与靶材料没有明显的关联,入射离子的Kα-X射线产额与其最初的电子组态有关,靶原子的X射线产额与入射离子的动能有关.     

高电荷态离子Arq+与不同金属靶作用产生的X射线

研究了高电荷态离子Ar^q+(q=16，17，18)入射金属Be，Al，Ni，Mo，Au靶表面产生的X射线谱.实验结果表明，Ar的Kα-X射线是离子在与固体表面相互作用过程中固体表面之下形成空心原子发射的.电子组态1s²的高电荷态Ar¹⁶⁺离子在金属表面中性化过程中，存在的多电子激发过程使Ar¹⁶⁺的K壳层电子激发产生空穴，级联退激发射Ar的Kα 特征X射线.Ar¹⁷⁺离子在金属表面作用过程中产生的X射线谱形与靶材料没有明显的关联,入射离子的Kα-X射线产额与其最初的电子组态有关，靶原子的X射线产额与入射离子的动能有关. 关键词： 高电荷态离子 空心原子 多电子激发 X射线     

低能高电荷态O~(q+)离子与Al表面作用产生的X射线

报道了 1.5—20 keV/q的高电荷态O~(q+)(q=3—7)离子与Al表面相互作用发射的O原子的特征X射线谱.分析表明,对于O~(q+)(q=3—6)离子入射时发射的X射线,是由于离子进入表面后与Al原子发生紧密碰撞导致的;而O~(7+)离子入射时的X射线,主要来自于"空心原子"的衰变.在动能相等的条件下,存在K壳层空穴的O~(7+)离子的X射线产额相较于O~(q+)(q=3—6)离子高一个数量级,不存在K壳层空穴的O~(6+)离子的X射线产额也要高于O~(3+),O~(5+)离子.总体来说,X射线产额以及电离截面与入射离子的初始电子组态有关,且随离子入射动能的增加而增加.根据半经典两体碰撞模型,本文估算了入射离子与靶原子相互作用时分别产生O和Al的K_α-X射线的动能阈值.对于入射动能低于动能阈值且电子组态为1s~2的O~(6+)离子与样品表面相互作用,可能存在多电子激发使O~(6+)离子产生K壳层空穴.     

129Xe20+入射Au表面X射线产额与离子动能的相关性

报道了在兰州重离子加速器国家实验室320kV高电荷态离子综合研究平台上,用2.4~6.0MeV动能的高电荷态离子129Xe20+轰击Au表面,探测X射线谱的实验结果。当离子动能较大时,相互作用不仅激发出了Au的M-X射线,还激发出了Xe的L-X射线,且X射线产额随入射离子动能的增加总体呈增加趋势。对碰撞导致X射线产生的微观机制进行了初步分析。     

129Xe20+入射Au表面X射线产额与离子动能的相关性

报道了在兰州重离子加速器国家实验室320kV高电荷态离子综合研究平台上,用2.4~6.0MeV动能的高电荷态离子129Xe20+轰击Au表面,探测X射线谱的实验结果。当离子动能较大时,相互作用不仅激发出了Au的M-X射线,还激发出了Xe的L-X射线,且X射线产额随入射离子动能的增加总体呈增加趋势。对碰撞导致X射线产生的微观机制进行了初步分析。     

Ar16+和Ar17+离子与Zr作用产生的X射线谱

将超导离子源提供的10-20keV/q Ar16 和Ar17 离子入射到Zr金属表面,在相互作用中产生的X射线谱表明,高电荷态Ar16 离子在金属表面中性化过程中有可能存在多电子激发,使Ar16 的K壳层电子被激发形成空穴,在退激过程中发射特征Kα-X射线.空心原子Ar的K层发射X射线强度随入射离子的动能而减弱,靶原子Zr的L壳层发射X射线强度随入射离子动能的增加而增强.Ar17 的单离子的Kα-X射线产额比Ar16 单离子的Kα-X射线产额大5个数量级.     

高电荷态离子轰击Au固体表面激发的特征光谱线

报道了高电荷态离子129X6+e和129X30+e轰击金属Au表面激发的200～1000 nm波段光谱的实验结果.实验结果表明：高电荷态离子所激发的靶原子的谱线强度与入射离子的电荷态密切相关,与入射离子的初动能没有强的相关性.     

低速Ar q+(q=7—14)离子入射Au表面激发的X射线谱

研究了高电荷态离子40Arq+(q=7—14)轰击金属Au表面产生的特征X射线谱。 实验结果表明, 在弱束流（nA量级）的情况下, 对于动能相同的入射离子, 当电荷态比较高（q=11）时, 便能有效地激发靶原子的特征X射线, 单离子的X射线产额高达10-8量级。 分析结果显示, 入射离子的势能、 动能和这种相互作用特有的镜像相互作用势能沉积在靶表面, 使靶原子内壳层电子激发和电离, 形成空穴和产生外壳层电子填充空穴辐射特征X射线,特征X射线的产额随入射离子的势能（电荷态）的增加而增加。 The Au atomic Mα characteristic X ray spectrum has been measured for the slow highly charged ions Arq+ (q= 7—14) impacting on Au surface. The result shows that as long as the charge state of projectile is higher（q=11）, the characteristic X rays of heavy atomic can be effectively excited even though the ionic beam is very weak(nA magnitude), and the single ionic X ray yield is in the order of 10-8 and increases with potential energies of projectiles.     

近Bohr速度的152Eu20+入射Au表面产生的X射线谱

测量了动能为2.0–6.0 MeV的高电荷态离子¹⁵²Eu²⁰⁺ 入射Au表面产生的特征X射线谱, 结果表明, 相互作用不仅激发出了Au的 M_ζ, M_α和M_δ特征X射线, 还激发出了Eu的M_α X射线, 且X射线总产额随入射离子动能的增加而增加. 计算了Au的M壳层总的X射线产生截面, 并与理论模型的计算结果做了比较分析. 关键词： 高电荷态离子 X射线 产额 截面     

X-ray spectra induced by <Superscript>129</Superscript>Xe<Superscript><Emphasis Type="Italic">q</Emphasis>+</Superscript> impacting the metal surface

Using the slow highly charged ions ¹²⁹Xe ^q+ (q = 25, 26, 27; initial kinetic T ₀⩽4.65 keV/a.u.) to impact Au surface, the Au atomic Mα characteristic X-ray spectrum is induced. The result shows that as long as the charge state of projectile is high enough, the heavy atomic characteristic X-ray can be effectively excited even though the incident beam is very weak (nA magnitude), and the X-ray yield per ion is in the order of 10⁻⁸ and increases with the kinetic energy and potential energy of projectile. By measuring the Au Mα-X-ray spectra, Au atomic N-level lifetime is estimated at about 1.33×10⁻¹⁸ s based on Heisenberg uncertainty relation. Supported by the National Natural Science Foundation of China (Grant Nos. 10574132, 10274088 and 10405025), the Talent Introduction Project of Xianyang Normal University (Grant No. 05XSYK103) and the Education Commission Foundation of Shaanxi Province (Grant No. 04JK300)     

Near infrared lights emission of <Superscript>40</Superscript>Ar<Superscript>16+</Superscript> impacting on metal surfaces

The highly charged ion ⁴⁰Ar¹⁶⁺ with the velocity (kinetic energy E _K=150 keV, velocity V=8.5×10⁵ m/s) smaller than Bohr velocity (V _Bohr=2.9×10⁶ m/s) was found to hove impacts on the surfaces of metals Ni, Mo, Au and Al, and the Ar atomic infrared light lines and X-rays spectra were simultaneously measured. The experimental results show that the highly charged ion that captures electrons is neutralized, and the multiply-excited hollow atom forms. The hollow atom cascade decay radiates lights from infrared to X-ray spectrum. The intensity of infrared lights shows that the metallic work functions play an important role in the neutralization process of highly charged ions during their interaction with metallic surfaces, which verifies the classical over-the-barrier model. Supported by the National Natural Science Foundation of China (Grant No. 10574132), the Natural Science Foundation of Shaanxi Province (Grant No. 2007A05) and the Talents Introduction Project of Xianyang Normal University (Grant No. 05XSYK103)     

X-ray spectra induced by slow highly charged Ar q + ions in collision with Nb surface

The X-ray spectra of Nb surface induced by Ar ^q+ (q = 16,17) ions with the energy range from 10 to 20 keV/q were studied by the optical spectrum technology. The experimental results indicate that the multi-electron excitation occurred as a highly charged Ar¹⁶⁺ ion was neutralized below the metal surface. The K shell electron of Ar¹⁶⁺ was excited and then de-excited cascadly to emit K X-ray. The intensity of the X-ray emitted from K shell of the hollow Ar atom decreased with the increase of projectile kinetic energy. The intensity of the X-ray emitted from L shell of the target atom Nb increased with the increase of projectile kinetic energy. The X-ray yield of Ar¹⁷⁺ is three magnitude orders larger than that of Ar¹⁶⁺. Supported by the National Natural Science Foundation of China (Grant Nos.10774149 and 10405025)     

X-ray spectra induced in highly charged 40Arq+ interacting with Au surface

By use of optical spectrum technology, the spectra of X-ray induced by highly charged ⁴⁰Ar ^q+ ions interacting with Au surface have been studied. The results show that the argon Kα X-ray were emitted from the hollow atoms formed below the surface. There is a process of multi-electron exciting in neutralization of the Ar¹⁶⁺ion, with electronic configuration 1s² in its ground state below the solid surface. The yield of the projectile Kα X-ray is related to its initial electronic configuration, and the yield of the target X-ray is related to the projectile kinetic energy.     

高电荷态离子与Si(110)晶面碰撞的沟道效应研究

不同电荷态低速离子(Ar^q+,Pb^q+)轰击Si(110)晶面,测量不同入射角情况下的次级粒子的产额. 通过比较溅射产额与入射角的关系,证实沟道效应的存在. 高电荷态离子与Si相互作用产生的沟道效应说明溅射产额主要是由动能碰撞引起的. 在小角入射条件下,高电荷态离子能够增大溅射产额. 当高电荷态离子以40°—50°入射时,存在势能越高溅射产额越大的势能效应. 关键词： 高电荷态离子 溅射 沟道效应     

Secondary ion emission under the bombardment of Si by multiply charged Si q+ ions

The spectra of secondary ion emission under the bombardment of a B-doped Si target by multiply charged Si ^q+ ions (q = 1?C5) have been studied in the energy range of 1 to 10 keV per unit of charge. A multifold increase in the yield of secondary cluster Sk _n ⁺ ions, multiply charged Si ^q/+ ion (q = 1?C3), and H⁺, C⁺, B⁺, Si₂N⁺, Si₂O⁺ is observed as the charge of the multiply charged ions increases. The increase in the yield of secondary ions with increasing charge of the multiply charged-ion charge is most significant for ions with relatively high ionization potentials.     

高电荷态Krq+与Al表面碰撞发射可见光的研究

利用低速(V≈0.01 V_Bohr)高电荷态Kr^q+ (q=8, 10, 13, 15, 17)离子轰击金属Al表面, 获得了碰撞过程产生的300–600 nm的光谱. 实验结果表明: 低能大流强(μA/cm²量级)离子束入射金属表面, 可产生溅射原子、离子和入射离子中性化后发射的可见光. 随着入射离子势能(电荷态)增加, 碰撞过程中发射谱线的强度增强. 与激发态3d能级相比, 较高的势能可以有效地激发Al原子的电子到较高4s能级. 关键词： 高电荷态离子 可见光发射 离子与表面作用     

高电荷态离子入射Al表面库仑势对靶原子特征谱线强度的影响

用同一动能(150keV)而不同电荷态的⁴⁰Ar^q+(8≤q≤16)离子入射金属Al表面,靶原子受激辐射产生特征光谱线. 实验结果表明：高电荷态离子与金属表面相互作用过程中,经过与靶原子碰撞(Penning碰撞)交换动能和共振电子俘获(resonant capture)释放库仑势能,将携带的能量沉积于靶表面,使靶原子激发. 这种激发不同于光激发,它不仅激发了原子复杂电子组态之间的跃迁,而且跃迁辐射的特征谱线强度增强的趋势与入射粒子的库 关键词： 高电荷态离子 库仑势 特征光谱 光谱强度