共查询到19条相似文献,搜索用时 31 毫秒
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导出了激光场中电子被中心势场散射的以分波相移表示的自由-自由跃迁吸收截面理论计算公式,以激光场中慢电子被He原子势场散射为例做了计算,说明对于自由-自由吸收截面,该公式的计算是有效的、方便的。 相似文献
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本文在一级Bom近似下,研究了激光场中正电子对基态氢原子的碰撞电离反应,并与入射粒子为电子的(e,2e)反应进行了对比.激光场中正电子态和敲出电子态分别采用Volkov波函数和Coulomb-Volkov波函数,靶原子的缀饰波函数由含时微扰论给出.计算结果显示激光缀饰的三重电离截面明显依赖于入射粒子电荷符号.激光越强,二者差距越大. 相似文献
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本文在一级Born近似下,研究了激光场中正电子对基态氢原子的碰撞电离反应,并与入射粒子为电子的(e,2e)反应进行了对比.激光场中正电子态和敲出电子态分别采用Volkov波函数和Coulomb-Volkov波函数,靶原子的缀饰波函数由含时微扰论给出.计算结果显示激光缀饰的三重电离截面明显依赖于入射粒子电荷符号.激光越强,二者差距越大. 相似文献
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本文用CPB(Coulomb-Projected Born)近似和GCPB(Generalised Coulomb-Projected Born)近似对激光场中电子与氢原子碰撞电离的三重微分截面及平均吸收或发射光子数进行了计算,并将结果与P.Cavaliers等(1980)的Born近似结果进行了比较。 相似文献
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激光场中电子与氢原子的散射:Ⅱ.低频近似下的计算 总被引:1,自引:1,他引:0
本文在多重散射理论的框架下,研究了低频激光场中电子与氢原子的散射。计算了激光场中电子与基态氢原子弹性散射的微分截面,讨论了微分截面随光子数、散射角以及入射电子能量的变化规律,并与别人的结果作了比较。 相似文献
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本文研究氢原子在会聚的线偏振强激光场中原子势的变化以及由此而引起的原子能级移位和波函数的空间扩展问题.结果表明,变化后的原子势等价于半径由外场决定而荷电量为核电荷的振荡球壳的势.在此势下,原子能级将变浅和分裂,波函数的空间分布将增大. 相似文献
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众所周知,氢原子跃迁的实质是能量的得失.跃迁方法除了通常的光子对氢原子的作用外,还有一种是实物粒子引起的;而实物粒子与氢原子相互作用产生的跃迁问题的处理容易出错,下面举一例. 相似文献
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A. Makhoute D. Khalil G. Rahali 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2006,37(1):75-82
The differential cross-section for electron-hydrogen
atom collisions in the presence of a linearly polarized laser
field is studied as a function of a scattering angle of low energy
electron by employing second-Born approximation (SBA). Detailed
analysis is performed in no forward scattering angle. 相似文献
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Sydney Geltman 《Journal of Quantitative Spectroscopy & Radiative Transfer》1973,13(7):601-613
Free-free absorption coefficients are calculated for the electron-neutral atom systems involving He, C, N, O, Ne, Ar, Kr and Xe. The calculations are based upon model atomic potentials which have been adjusted to fit experimental scattering cross sections or electron affinities. Some angular distributions are presented and thermal averages are evaluated in the ranges λ = 0.5–20 μm and T = 500–20,000°K. 相似文献
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Free-free transitions form a substantial part of the thermal emission of plasmas at high temperatures and long wavelengths. The modifications caused by charged perturbing particles, especially electrons, are estimated for the case of a hydrogen plasma by the use of the Debye-Hückel potential and compared with other approximations. 相似文献
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LaGattuta KJ 《Physical review letters》1988,60(8):692-695
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We show theoretically that the muon lifetime can be changed dramatically by embedding the decaying muon in a strong linearly polarized laser field. Evaluating the S-matrix elements taking all electronic multiphoton processes into account we find that a CO(2) laser with an electric field amplitude of 10(6) V cm(-1) results in an order of magnitude shorter lifetime of the muon. We also analyze the dependencies of the decay rate on the laser frequency and intensity. 相似文献
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Miaja-Avila L Lei C Aeschlimann M Gland JL Murnane MM Kapteyn HC Saathoff G 《Physical review letters》2006,97(11):113604
We report the first observation of the laser-assisted photoelectric effect from a solid surface. By illuminating a Pt(111) sample simultaneously with ultrashort 1.6 eV and 42 eV pulses, we observe sidebands in the extreme ultraviolet photoemission spectrum. The magnitude of these sidebands as a function of time delay between the laser and extreme ultraviolet pulses represents a cross-correlation measurement of the extreme ultraviolet pulse. This effect promises to be useful to extend extreme ultraviolet pulse duration measurements to higher photon energies, as well as opening up femtosecond-to-attosecond time-scale electron dynamics in solid and surface-adsorbate systems. 相似文献
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Mechanical texturing is the dominant technique for texturing magnetic media and is widely used in current hard disk drive
manufacturing processes. This technique possesses the advantages of easy operation and low cost. However, it has an inherent
disadvantage since mechanical texturing leads to jagged profiles randomly generated on hard disk surfaces, which precludes
its further use in low-fly-height cases. A laser-assisted process working at near-threshold fluences for mechanical texturing
was proposed to buff the irregular profiles of mechanical textures formed on Ni-P disk surfaces using a KrF excimer laser
(λ=248 nm,τ=23 ns). This process, based on selective melting of the Ni-P surfaces due to inhomogeneous deposition of laser
energy, was found to be capable of improving the surface characteristics of mechanically textured Ni-P disks. VSM and XRD
analyses demonstrated that magnetic and structural properties of the Ni-P surfaces would not be affected in a detrimental
way so as to influence the recording features of the magnetic media after laser buffing.
Received: 28 November 2000 / Accepted: 12 December 2000 / Published online: 3 April 2001 相似文献
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T.L. John R.J. Williams 《Journal of Quantitative Spectroscopy & Radiative Transfer》1977,17(2):169-174
A multichannel theory is used to investigate free-free absorption by electrons moving in the field of neutral nitrogen and oxygen atoms. Tables of the free-free absorption coefficient are given for a range of temperatures and frequencies, and include details of contributions from various transitions involving ground state terms. 相似文献