镁原子MgI3snd^1,3D2序列能谱及寿命的研究

本文用多通道量子数亏损理论（ＭＱＤＴ）对镁原子ＭｇＩ单激发Ｒｙｄｂｅｒｇ序列３Ｓｎｄ＾１，３Ｄ２激发态能级结构和能态寿命进行了理论分析和详细的计算，预言了３ｓｎｄ＾１，３Ｄ２序列ｎ≤３０的未知能级及其寿命值，此外，我们还首次预言了实激发态３Ｐ＾２＾１Ｄ２能级位于５４３３０．２６ｃｍ＾－１处。     

利用双色光子存储方法测量偶氮分子甲基橙和乙基橙的亚稳态寿命

提出了用双色光子存储来测量寿命的新办法，逐渐延长关闭预激光发光与打开写入光束的时间间隔，通过分析衍射信号的变化得到相关能级的寿命，用此方法测得偶氮分子甲基橙和乙基橙的亚稳态寿命分别为４ｓ和２．７ｓ．     

NiI的中性激发光谱和能级寿命的测定

文中描述了利用束箔方法研究能量为１１０ｋｅＶ的Ｎｉ＋离子与厚度为８．５μｇ／ｃｍ２的碳箔相互作用的激发光谱和能级寿命，以及实验测量结果的分析。     

用振荡偶极子模型计算能级寿命

对能级寿命的物理意义作了较全面的阐述，并运用半径费、半量子理论近似，采用振荡偶极子模型对能级寿命进行了计算，所得结果与各种文献所用结论十分一致。     

用振荡偶极子模型计算能级寿命

对能级寿命的物理意义作了较全面的阐述，并运用半经典、半量子理论近似，采用振荡偶极子模型对能级寿命进行了计算，所得结果与各种文献所用结论十分一致．     

掺铒铌酸锂晶体的上转换发光

首次报道了掺铒铌酸锂晶体的频率上转换发光效率和该晶体的全吸收谱、绿光发射上能级＾４Ｓ３／２态的荧光寿命，以及其与温度变化的关系等，并讨论了上转换发光的机制及实现其激光运转的可能性。     

负碳离子(2s~2p~3)和(2s~12p~4)的光离解

电子关联效应在负离子中的作用相当重要，本文讨论了负碳离子（２ｓ２ｐ３）和（２ｓ１２ｐ４）的能级结构、光谱跃迁、寿命和光离解通道等。碳负离子（１ｓ２２ｓ１２ｐ４）的双重态比四重态稳定，（２ｓ２ｐ３）和（２ｓ１２ｐ４）之间各辐射谱线波长位于超紫外区域的上限附近，其光谱强度很大的波长有６条，为研制Ｘ射线激光提供了有利的工作物质。     

激光金等离子体中Au^49＋能级寿命的相对论多组态计算

根据扩展的相对论多组态Dirac-Fock理论，采用“多功能相对论原子结构程序”，计算了类锌Au^49 的能级寿命、能级宽度和光谱跃迁波长。计算所得的波长值与实验结果符合较好；能级寿命与能级宽度的大小关系符合海森堡的能量与时间测不准原理。     

负碳离子（2s^22p^3）和（2s^12p^4）的光离解

电子关联效应在负离子中的作用相当重要，本文讨论了负碳离子（２ｓ＾２２ｐ＾２）和（２ｓ＾１２ｐ＾４）的能级结构、光谱跃迁、寿命和光离解通道等。碳负离子（１ｓ＾２２ｓ＾１ｐ＾４）的双重态比四重态稳定，（２ｓ＾２２ｐ＾４）和（２ｓ＾１２ｐ＾４）之间各辐射谱线波长位于超紫外区域的上限附近，其光谱强度很大的波长有６条，为研制Ｘ射线激光提供了有利的工作物质。     

NH2自由基A^2A1,X^2B1电子振动能级结构及A^2A1～X^2B1 …

大振幅变曲振动哈密顿和矩阵变换变化,考虑Ｒｅｎｎｅｒ－Ｔｉｌｌｅｒ效应,计算了ＮＨ２自由基Ａ＾２Ａ１,Ｘ＾２Ｂ１态电子弯曲振动和Ｋ型转动能级。由计算得到的态函数和基态电偶极矩,计算ＮＨ２自由基Ａ＾２Ａ１～Ｘ＾２Ｂ１电子振动相对跃迁矩和电子激发态Ａ＾２Ａ１的荧光寿命,理论计算结果与」实验值符合较好。     

Effect of radio frequency field on toroidal plasma parameters

Low temperature plasma parameters in a toroidal magnetic field are measured. The effect of an externally applied perpendicular electric field on the plasma parameters is studied. The lifetime of the plasma is measured in the presence and absence of the RF electric field. Decrease in the plasma lifetime in the presence of RF field is attributed to detrapping of the primary electrons to a larger volume. Plasma lifetime increases when a small vertical magnetic field is added to the toroidal magnetic field.     

磁场对氩原子ArI5p[3/2]2能态碰撞消激发与碰撞消取向的影响

在空心阴极放电激光诱导荧光实验中，当加强外磁场于观察方向，采用“魔角”激发，对氩原子ArI5p［3/2］₂能态，外磁场强度越强，则碰撞消激发速率越快，而碰撞消取向速率反而越慢，其总的效果是导致弛豫曲线的衰减速率随磁场强度增强而变缓．ArI5p［3/2］₂的自然能级寿命在不加外磁场情况下为120±5ns． 关键词：     

First observation of trapped high-field seeking ultracold neutron spin states

Ultracold neutrons were stored in a volume, using a magnetic dipole field shutter. Radial confinement was provided by material walls. Low-field seeking neutrons were axially confined above the magnetic field. High-field seeking neutrons are trapped inside the magnetic field. They can systematically shift the measured neutron lifetime to lower values in experiments with magnetic confinement.     

Depolarization of the photoluminescence and spin relaxation in n-doped GaAs

Optically oriented electron spin lifetime in n-doped gallium arsenide was measured via depolarization of the photoluminescence (PL) in a transverse magnetic field (Hanle effect). In order to measure the PL polarization, a time-resolved pump-probe experiment, where a pump pulse generates spin-polarized electrons and a probe pulse monitors their polarization, was employed. The PL polarization in dependences of the pump-probe delay, external magnetic field as well as of the sample temperature was studied. The PL polarization was found to decay exponentially with the pump-probe delay, from which the spin lifetime of the electrons was measured. The measured value was found to depend on the strength of the magnetic field and sample temperature.     

Estimation of the chiral magnetic effect considering the magnetic field response of the QGP medium

The magnetic field plays a major role in searching for the chiral magnetic effect in relativistic heavy-ion collisions. If the lifetime of the magnetic field is too short, as predicted by simulations of the field in vacuum, the chiral magnetic effect will be largely suppressed. However, the lifetime of the magnetic field will become longer when the QGP medium response is considered. We give an estimate of the effect, especially considering the magnetic field response of the QGP medium, and compare it with the experimental results for the background-subtracted correlator H at RHIC and LHC energies. The results show that our method explains the experimental results better at the top RHIC energy than at the LHC energy.     

Phonon-plasmon modes in a strong magnetic field

Frequencies of phonon-plasmon coupled modes in a strong magnetic field were calculated. The calculations were performed in the long-wave approximation with regard to the electron damping and intrinsic lifetime of optical phonons. The dependence of the Raman scattering cross section on the carrier concentration and the magnetic field intensity was calculated.     

核自旋单重态的制备及其转化效率和寿命的影响因素分析

长寿命核自旋单重态（LLS）因具有寿命较长这一特性而具有广泛的应用前景.本文在一个三肽样品（alanylglycylgcine,AGG）的水溶液中,对结构中离手性碳较远的二自旋体系进行核自旋单重态的制备,并探究了样品浓度、温度、射频发射中心位置、自旋体系之间的J耦合常数,以及磁场不均匀性五个因素对LLS的转化效率及其寿命的影响.实验结果表明,核自旋单重态的转化效率和寿命均不受样品浓度以及磁场不均匀性的影响.寿命会随实验温度的升高不断增加,转化效率随温度的下降而减小.射频中心位置在小范围内变化时,核自旋单重态制备所受影响不明显;但当变化较大时,其转化效率与寿命明显减小.同时,核自旋单重态对J耦合的变化则比较敏感,当J值选择不精准时,转化效率及寿命都出现明显降低.     

Improvement of the spin polarization lifetime in the 85Rb vapor cell by octadecyltrichlorosilane coating

Effective surface coatings allow for long spin polarization in alkali metal cells, suppressing the magnetic field gradient effect and providing an improvement in atomic magnetometer sensitivity. In this work, the effect of an octadecyltrichlorosilane (OTS) surface coating on the longitudinal and transverse spin polarization lifetime of an optically pumped ⁸⁵Rb vapor cell has been studied. Our results showed that the spin polarization lifetime significantly increased in the OTS lined cell compared to the unlined cell. The relaxation rate due to alkali metal atoms wall collisions and the magnetic field gradient has been decreased by using an OTS surface coating. A longer spin polarization lifetime in the lined cell causes a narrower magnetic resonance line width and subsequently a more sensitive atomic magnetometer.     

霍尔推力器放电通道溅射腐蚀计算

 为了预示霍尔推力器的寿命,建立了推力器粒子束放电通道的2维电磁场模型,模拟的推进剂为氙。利用PIC方法跟踪粒子在电磁场中的运动。磁场的求解采用拉普拉斯方程,电场的求解采用泊松方程。电子由阴极喷入通道,并在电磁场中与原子发生电离碰撞生成离子。在跟踪离子的过程中记录下撞击到内外壁面的离子个数、角度和能量。利用记录下的参数进行腐蚀计算,得到当溅射阈值能量分别为10,20,30,40,50 eV时通道壁面的腐蚀速率。推力器放电通道出口附近的最大腐蚀速率约为1.7×10^-9 m/s。     

Magnetic field effect on the H2CS fluorescence from the first excited singlet state Ã1A2

Fluorescence intensity in thioformaldehide vapours (H₂CS), excited to the ÃA₂ different vibronic levels of the ùA₂ ? [Xtilde]¹A₁ transition, were measured as a function of an external magnetic field. On excitation to these levels, dynamics in zero and non-zero field may be described in the small-molecule limit, with fluorescence exhibiting an almost exponential decay. A magnetic field changes the integrated intensity and decay lifetime of the thioformal-dehide fluorescence induced from different vibronic levels of the ù A₂ state. We found that the magnetic field effect grows at lower gas pressures. The measured field dependences of the magnetic field effect can be fitted using field-saturated functions. The measured data were explained by the indirect mechanism theory (nuclear-spin and electron-spin decoupling mechnism).