Relativistic RRR-matrix studies of photoionization processes of Ar~(5+)

The 3s–np photoionization processes of the ground state 2P1/2 and the metastable state 2P3/2 of Ar5+ are investigated using our recently developed relativistic R-matrix code, where the interactions between the bound states and the continuum states are included. Both resonance positions and the oscillator strengths are in much better agreement with the absolute experimental measurements by Wang et al. [Wang J C, Lu M, Esteves D, Habibi M, Alna'washi G and Phaneuf R A 2007 Phys. Rev. A 75 062712] with a resolution of 80 meV than their theoretical results. The contributions of the two experimental unresolved transitions are distinguished in our calculations, which show that the transitions from the ground state also make significant contributions to some resonances. Our theoretical results are also in good agreement with the measurements for the first resonance with a higher resolution of 20 meV.     

Untersuchungen zur Adsorption 14C-markierter Flotationssammler an Alkalisalzen

Mit Hilfe einer radiometrsichen Analysenmethode wird die Adsorption von ¹⁴C-markiertem Octadecylaminhydrochlorid an Kaliumchlorid in Gegenwart von unselektiven Zusatzstoffen. Dabei zeigt sich, daß die Aminadsorption hauptsächlich durch solche aliphatische Zusätze verbessert wird, die eine genügend lange Alkylkette besitzen. Die polare Gruppe hat meist keinen wesentlichen Einfluß. Versuche mit Quarz in Abhängigkeit vom Elektrolytgehalt der Trübe ergeben, daß die bisherige Deutung nicht ausreichend ist. Dodecanol-¹⁴C wird mur dann gemeinsam mit dem Amin vom Salz adsorbiert, wenn die kritsiche Mizellbildungskonzentration überschritten wird. Aus solchen gemischten Mizellen entstehen Sammlerfilme, die sehr gute Flotation des Kaliumchlorids bewirken.     

The N(p,γ)O low-energy S-factor

The ¹⁴N(p,γ)¹⁵O low-energy S-factor is analyzed using the R-matrix model. We find that the g.s. contribution is less than previously reported. The S-factor is mainly given by the 6.79 MeV state contribution which is determined by its asymptotic normalization constant (ANC). Consequently, the S-factor at zero energy is lower by a factor of 1.7 compared to the values given in recent compilations. This result may affect the nucleosynthesis and time scale evolution in massive stars. New measurements of the ¹⁴N(p,γ)¹⁵O cross section over a wide energy range, and especially at low energies, are highly desirable. Significant improvement could be also obtained from the ANC measurement of the 6.79 MeV state.     

CIV共振谱线的电子碰撞展宽的理论计算

 使用R-矩阵方法,利用碰撞近似和密耦理论,计算了确定CIV 2s²S-2p²P⁰共振谱线的碰撞参数,并由此得到了在电子密度为10¹⁷cm^-3 的条件下,共振谱线的线宽和线移随温度的变化关系。计算得到的线宽与半经典的理论计算值符合得比较好,但大约只有实验线宽的一半。     

电子与Mg5+碰撞激发的碰撞强度研究

采用多通道R-matrix程序计算了电子与Mg5 离子碰撞激发的碰撞强度.所有的跃迁均限定在主量子数为2的态之间.计算结果与用相对论扭曲波方法得到的结果进行了比较,R-matrix方法所得的结果更好.文中列出了部分光允许跃迁的数据,可以看出,R-matrix方法更适合计算低能碰撞.     

低能电子与Li原子碰撞激发的R矩阵计算

采用二态密耦Ｒ矩阵方法，在入射电子能量１－１０ｅＶ内，我们计算了电子与Ｌｉ原子碰撞的２ｓ→２ｓ，２ｐ弹性和激发截面，并和可行的理论、实验进行了比较和讨论。     

电子碰撞原子弹性散射的扭曲波解

使用Ｓｌａｔｅｒ型轨道参数描述束缚电子，连续电子与靶之间的相互作用，采用静势近似，充分利用Ｒ－矩阵程序包中的现有资源，首次在“二区”近似图象下，建立了我们自己的计算扭曲库仑波函数的计算方法，并编制了标准程序。     

Effective collision strengths among the fifteen lowest states of FeXVII

Collision strengths have been calculated for electron impact excitation of neon-like Fe XVII for all transitions within its 15 lowest states. Configuration interaction wavefunctions have been used to represent the target states. The standardR-matrix code has been used to calculate the contribution from the lower scattering partial waves (L⩽9), while the no exchange version of the same code has been used to compute efficiently the contribution of higher partial waves (L⩾10). Effective collision strengths for all the 105 transitions are tabulated for elected temperatures in the range logT _e=5.40 to logT _e=7.00 withT _e expressed in °K.     

Two-Parameter Quantum Groups and Drinfel'd Doubles

We investigate two-parameter quantum groups corresponding to the general linear and special linear Lie algebras and . We show that these quantum groups can be realized as Drinfel'd doubles of certain Hopf subalgebras with respect to Hopf pairings. Using the Hopf pairing, we construct a corresponding R-matrix and a quantum Casimir element. We discuss isomorphisms among these quantum groups and connections with multiparameter quantum groups.