共查询到18条相似文献,搜索用时 109 毫秒
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铀原子多色三光子共振电离谱研究 总被引:2,自引:1,他引:1
利用Nd:YAG二倍频激光同步泵浦的脉冲染料激光系统、原子束装置、飞行时间质谱和Boxcar技术测量了^238U的多色三光子共振电离谱。研究了电场对铀原子第一激发态的影响。解决了如何确定三角三光子共振电离谱图中所含的单色,双色和三色共振电离峰的问题。 相似文献
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用激光增强电离光谱(LEIS)方法进行钠原子的灵敏检测 总被引:2,自引:1,他引:1
用脉冲可调谐染料激光共振激励火焰中的钠原子。通过测量钠原子的激光增强电离光谱(LEIS)信号进行钠原子的灵敏检测,实际的检测限可达10~(-11)g/ml。 相似文献
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用三台可调谐脉冲染料激光器三步共振电离方法,测量铀原子在电离限附近的能级。测量了在49733-50224cm^-1能量区的40余个能级位置。 相似文献
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把脉冲可调谐染料激光器的激光调谐到钠原子3~2S_(1/2)—3~2P_(1/2)的共振激发线(ν=16961cm~(-1)),激励火焰中的钠原子。通过激光饱和激励感生非共振荧光光谱方法进行钠原子的灵敏检测,实际的检测限可达10~(-11)g/ml。 相似文献
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自从染料激光器问世以来,发展是十分迅速的.这是由于它是激光光谱学不可缺少的手段之一.高分辨率激光光谱用来研究物质的超精细结构;超短脉冲的时间和空间高分辨率光谱用来研究物质的瞬态变化及微观动力学过程;在工业上用激光光谱可进行微量和超微量的高灵敏度的物质分析.此外,可调谐染料激光器在同位素分离、光化反应等方面也有着极其重要的意义. 近年来我们研制了 QJR2-1 型和QJR-2型可调谐染料激光器.在QJR2-1型可调谐染料激光器的某些技术参数的基础上,我们做了部分的修改,研究了染料激光器的性能.主要进行波长调谐范围,用光栅和法… 相似文献
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利用Nd:YAG激光泵浦的脉冲染料激光、原子束装置和飞行时间分辩质谱仪在602.7-621.0nm光谱范围内测量了铀原子单色三光子电离光谱。 相似文献
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利用脉冲染料可调谐激光激发原子密度为10~(14)~10~(18)cm~(-3)的稠密碱金属钾蒸气,在5780(?)~5920(?)波段内测量了激光共振电离光谱.结果表明,除了钾原子4s—nd(n=10~16)、4s—ns(n=12~18)双光子跃迁以外,还出现了钾4P—7s、4P—5d跃迁.这种跃迁的电离光谱信号是由于在钾蒸气中钾分子-原子混合双光子跃迁而产生的.本文对钾蒸气混合双光子跃迁进行了讨论. 相似文献
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V. N. Fedosseev B. A. Marsh D. V. Fedorov U. Köster E. Tengborn 《Hyperfine Interactions》2005,162(1-4):15-27
The resonance ionization laser ion source (RILIS) of the ISOLDE on-line isotope separation facility is based on the method
of laser step-wise resonance ionization of atoms in a hot metal cavity. The atomic selectivity of the RILIS complements the
mass selection process of the ISOLDE separator magnets to provide beams of a chosen isotope with greatly reduced isobaric
contamination. Using a system of dye lasers pumped by copper vapour lasers, ion beams of 24 elements have been generated at
ISOLDE with ionization efficiencies in the range of 0.5–15%. As part of the ongoing RILIS development off-line resonance ionization
spectroscopy studies carried out in 2003 and 2004 have determined the optimal three-step ionization schemes for scandium,
antimony, dysprosium and yttrium. 相似文献
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用共振电离质谱测定铀原子奇宇称高激发态能级 总被引:1,自引:1,他引:0
对铀原子单色和双色多光子共振电离光谱开展了深入的研究。报道了用双色三步共振光电离技术测量位于33003 ̄34264cm^-1范围内的奇宇称高激发态能级的位置。利用总角动量选择定则指定了这些能级的总角动量J值。 相似文献
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以速率方程为基础,通过数值模拟方法,对Pb的激光共振电离通道:“6s26p2 3P0—6s26p7s 3P01—电离”的激光诱导同位素歧视效应进行了研究,以探讨减小激光诱导歧视效应,准确测定Pb同位素比值的有效途径。通过考虑激光线型、原子吸收谱线线型、同位素位移及同位素超精细结构等因素的影响,对速率方程进行近似。在近似的速率方程基础上,以“1+1”激光共振电离过程为例,进而探讨激光峰值功率密度、带宽和中心波长对Pb的同位素歧视效应的影响。研究结果表明,利用最佳波长法,可基本消除同位素歧视效应的影响;提高激发光光强可使Pb同位素饱和电离,从而消除同位素歧视效应的影响;采用宽带激光激发,可减小同位素歧视效应的影响。 相似文献
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A. M. Prokhorov V. V. Buchanov M. A. Kazaryan M. M. Kalugin 《Journal of Russian Laser Research》2002,23(6):580-589
Isotopically selective photoionization of silicon atoms by laser radiation using tunable dye lasers is considered. The scheme of atomic ionization with two-photon excitation via the resonance level of one of the high states with subsequent excitation of the autoionization state is proposed. The calculations carried out show that the up-to-date development of laser facilities allows one to evaluate the ultimate production of the highly enriched 28Si isotope at a level of 0.1 g/h at a radiating power of 1 W for each wavelength. The excitation selectivity appears to be high (about 100) within the framework of the radiation problem and is actually defined by the conditions of ion extraction, background atom concentration, charge exchange, and so on rather than by the radiation processes. 相似文献
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Atomic sulphur ions (S+) were observed directly by crossing a carbonyl sulphide (OCS) molecular beam with a F2 laser. In this study both S+ ion and electron images were measured using the velocity map imaging technique. The results imply that S+ is produced from the well-known photodissociation of OCS at 157 nm leading to the dominant S(1S) + CO(1Σ+) channel, and then the excited S(1S) atom is directly ionized by another 157 nm photon. Correlated vibrationally resolved angular distributions and internal energy distribution of the CO coproducts are reported here and compared with previous studies. This experiment yields strong and sharp S+ images which may be useful for calibrating any imaging or laser ionization apparatus when using a 157 nm laser. A number of technical aspects such as corrections for partial slicing and imperfect laser polarization are described. Abstraction of product angular distributions using both polarized and unpolarized photolysis lasers is also demonstrated using velocity map imaging. 相似文献
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R. Talukdar A. Tripathy P.N. Bajaj P.K. Chakraborti G.D. Saksena 《Optics Communications》1983,45(3):179-182
Crossed laser molecular beam configuration was used to study the photoionization of U and UO by the UV-lines of an argon ion laser. Photoionization efficiencies of both U and UO were found to be line sensitive. Photoionization by the 3638 Å line was observed for the first time. Uranium atom ionization efficiency being higher for the 3345 Å and 3511 Å groups of lines, while UO ionization efficiency being maximum for the 3638 Å line. Dependence of photoion signal on laser power and relative photoionization efficiencies of the two isotopic species of uranium are also investigated. 相似文献
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The detection of long-lived plutonium isotopes in ultra-trace amounts by resonance ionization mass spectrometry (RIMS) is
a well-established routine method. Detection limits of 106 to 107 atoms and precise measurements of the isotopic composition have been achieved. In this work multi-step resonance ionization
of plutonium atoms has been performed with tunable lasers having very different output intensities and spectral properties.
In order to compare different ways for the resonance ionization of plutonium broadband pulsed dye and titanium:sapphire lasers
as well as narrow-band cw-diode and titanium:sapphire lasers have been applied for a number of efficient excitation schemes.
It has been shown, that for identical excitation schemes the optical isotope selectivity can be improved by using cw-lasers
(bandwidths < 10 MHz) instead of pulsed lasers (bandwidths > 2 GHz). Pulsed and cw-laser systems have been used simultaneously
for resonance ionization enabling direct comparisons of pulsed and continuous ionization processes. So far, a three-step,
three-color laser excitation scheme has been proven to be most practical in terms of efficiency, selectivity and laser wavelengths.
Alternatively a newly discovered three-step, two-color excitation scheme which includes a strong two-photon transition from
an excited state into a high-lying autoionizing state yields similar ionization efficiencies. This two-photon transition was
characterized with respect to saturation behavior and line width. 相似文献
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B. A. Marsh V. N. Fedosseev D. A. Fink T. Day Goodacre R. E. Rossel S. Rothe D. V. Fedorov N. Imai M. D. Seliverstov P. Molkanov 《Hyperfine Interactions》2014,227(1-3):101-111
Since 2011 the ISOLDE Resonance Ionization Laser Ion Source (RILIS) has comprised a dual system of three dye and three Ti:sapphire lasers capable of gap-free wavelength tuning from 210 to 950 nm. Temporal synchronization of the lasers has enabled several operating modes to be established which make optimal use of the complementary characteristics of each laser type. This flexibility of the system has presented several opportunities for additional atomic spectroscopy studies and ionization scheme development, whilst also enabling an increase in the number of operating hours for standard ion beam production. The extended capabilities of the dual-RILIS system are exemplified by the recent operational highlights. These include on-line ionization scheme development (At, Ca), measurements of ionization energies (At, Po), in-source resonance ionization spectroscopy of exotic isotopes (At, Au, Po), and the provision of a fibre-coupled narrow-linewidth Ti:sapphire beam for the on-line commissioning of the CRIS experiment (Fr). 相似文献