Resonance states of Ps- using correlated wave functions
Abstract We have investigated the F e 1 , 3 resonance states of positronium negative ion below the N = 3 , 4 and 5 Ps thresholds using highly correlated exponential wave functions. Resonance parameters (positions and widths) are extracted employing both the stabilization method and the complex-coordinate rotation method. In addition to many Feshbach resonances below the various Ps thresholds, we have identified two F e 1 shape resonances with one each lying above the N = 3 and N = 5 thresholds, respectively. We have also identified three F e 3 shape resonances with one lying above the N = 3 threshold and two lying above N = 4 threshold. The F e 1 , 3 shape resonances associated with N = 3 Ps threshold and some other Feshbach resonances are reported for the first time in the literature.
High-lying doubly excited resonances in Ps− interacting with screened Coulomb potentials
Abstract The effect of screened Coulomb potentials on the high-lying doubly-excited resonance states of the positronium negative ion has been investigated using the method of complex-scaling together with employing highly correlated Hylleraas-type wave functions. Resonance parameters (resonance energy positions and widths) below the N  = 4, 5, and 6 Ps thresholds for various screening parameters are determined.
Line Arrester Energy Discharge Duties
Surge arresters could practically eliminate lightning flashovers on distribution lines, if they are properly deployed in large enough numbers, and if they could survive the current and energy discharge duties imposed by high-magnitude lightning strokes. The discharge duty depends on complex interactions between the arrester locations, grounding, shielding from nearby objects, and the local lightning environment. But many factors of traditional concern with distribution arrester application, such as the lead length, surge front time, and protective margin, play little or no role in the discharge duty. Probabilistic methods determine the expected arrester failure rate. This should be much lower than the original flashover rate on the line insulation, otherwise the design is not acceptable. A transient program such as EMTP/ATP provides the best tool for calculating the discharge duty, but simplified methods are also available