Calculation of Elastic Scattering Properties in an Ultra-Cold ^85Rb-^85Rb Vapour

We report the calculation of the same-species elastic scattering properties for the ultracold rubidium-rubidium (^85Rb-^85Rb) system and the results are compared with other theoretical and experimental results in detail. We present an improved potential for triplet ground states of the Rb2 molecule, and calculate the scattering lengths αt and the effective range re using WKB and Numerov methods for two rubidium-85 collisions in the triplet state. Also, we investigate the convergence of these scattering properties, i.e. the dependence on core radius and K^0 parameter using quantum defect theory and the analytic calculations of scattering length obtained by Szmytkowski. In addition, we present evaporative cooling and other results that include phase shift and cross section at zero energy limit.     

Variable Phase Method Used to Calculate Ultracold Scattering Properties of 7Li33Cs

Elastic scattering properties of singlet and triplet states of ^7 Li^133 Cs at ultralow temperatures are calculated using the constructed potential curves gleaned from high-precision spectroscopy measurement. We show how to reach the scattering length and the number of bound states via the vaxiable phase method. The scattering lengths of the singlet and triplet states of^7 Li^133 Cs are 50.5 a.u. and -135.7 a.u., respectively. We derive two corrections, arising from long range interactions, accurately to at least first order, which provide upper and lower computed bounds to the scattering length. Our results are consistent with the recent experimental data and the theoretical calculation.     

原子核密度经验公式与轻子-核DIS过程的核效应

在核密度模型基础之上利用原子核密度经验公式得到的核密度和利用电磁半径平方平均值得到的核密度分别计算了轻子 核深度非弹性散射过程中的核效应函数RHe/D(x, Q2), RLi/D(x, Q2), RC/Li(x, Q2), RCa/Li(x, Q2), 发现利用由原子核密度经验公式得到的核密度计算核效应函数所得结果与NMC实验数据符合得较好, 并且优于用后者方法计算核效应函数的理论结果, 从而说明利用原子核密度经验公式研究核子结构函数核效应的合理性。 The nuclear effect functions in l A DIS process RHe/D(x, Q2), RLi/D(x, Q2), RC/Li(x, Q2) and RCa/Li(x, Q2) are calculated on the basis of the nuclear density model by using nuclear densities obtained from an empirical formula or the experimental values of the electromagnetic mean of radius square 〈r2〉, respectively．It is shown that the nuclear effect functions obtained from the empirical formula are in good agreement with the NMC experimental data, and better than the later ones．The empirical formula of the nuclear density can be used to study the nuclear effect of nucleon structure functions reasonably.     

探索夸克存在的证据

 1947年,汉生(W.W.Hansen)正在用第一台电子直线加速器作实验. 1968年10月费因曼正在用部分模型解释电子质子深度非弹性散射的实验结果.     

强力、弱力和电磁力的大统一(Ⅴ)

天然放射性的发现打破原子“永恒不变”的神话之后,比原子-分子尺度要小得多的亚原子粒子陆续发现:1897年,J. J. 汤姆生通过测定阴极射线的荷质比发现了第一个亚原子粒子,称其为“微粒”,并将其所带电荷称为“电子”.     

Absolute Differential Cross Sections for Elastic Scattering of Electrons from CO at Intermediate and High Energies

The additivity rule model together with the complex optical model potential correlated by the concept of bonded atoms, which considers the overlapping effect of electron clouds between two atoms in a molecule, is firstly employed to calculate the absolute differential cross sections for electrons scattered by carbon monoxide at intermediate and high energies at the Hartree-Fock level. A comparison of elastic differential cross section results, obtained by using the correlated complex optical model potential, with the available experimental data,shows a significant improvement over the uncorrelated ones. The differential cross sections obtained by using thecorrelated complex optical model potential are in very good agreement with the experimental data. It is shown that the additivity rule model together with the correlated complex optical model potential is suitable for the calculations of the absolute differential cross sections of e-CO scattering.     

Excited States in ^18Ne Studied via ^17F＋p

The elastic resonance scattering of ^17F＋p is studied in inverse kinematics via a thick-target method. The excitation function for ^17F＋p elastic scattering is obtained within the energy interval of Ec.m ≈ 0.4-1.7 MeV. The experimental excitation function is analyzed with a multilevel R-matrix code MULTI7, and the proton widths are deduced. The α decay from 6.15 MeV 1- state in 18Ne is observed, which is critical to the 14O（α, p）17F reaction as the main breakout route from CNO cycle to rp-process in supernovae and x-ray bursts.     

Elastic Scattering of Ultracold 23Na and 39K Atoms in the Singlet State

The elastic scattering properties for collisions between ultracold 23Na and 39K atoms in the singlet state are investigated. Based on the recent theoretical and experimental results, the improved hybrid potential is presented for the singlet X1Σg＋ ground state of NaK. By means of the Numerov and semiclassical methods, the values of the s-wave scattering length a for the singlet state are calculated to be 33.3757a0 and 37.9399a0, respectively. Pronounced shape resonances appear for the l = 1 partial wave for the X1Σg＋ state. In addition, the s-wave scattering cross section, total cross section and energy positions of shape resonances for the X1Σg＋ state are discussed.     

格列吡嗪与牛血清白蛋白相互作用的分子光谱法的改进实验

在pH 7.40的Tris-HCl缓冲溶液中,利用以蛋白荧光变化为考察对象的传统荧光光谱法和以药物荧光变化为考察对象的弹性散射荧光法,分别研究了293和303K温度下格列吡嗪(Gli)与牛血清白蛋白(BSA)之间的反应机理,两种方法所得结论均一致。即Gli与BSA之间猝灭方式为动态猝灭;两者主要通过疏水作用力结合,结合位点主要位于BSA的疏水区,结合位点数约为1;Hill系数nH小于1,表现为弱的负协同作用。弹性散射荧光法得到的Gli-BSA体系的结合常数均比传统荧光光谱法大,表明以药物荧光变化为考察对象的研究更准确、合理,并通过紫外光谱法对其所得结果的合理性进行了验证。结果表明:传统荧光光谱法利用蛋白为研究对象,研究药物与蛋白之间的相互作用存在一定的不足,其谱图只能反映蛋白分子与药物相互作用的部分信息,而弹性散射荧光法利用药物为研究对象,能够更全面、准确地表达药物与蛋白之间的作用信息。