The neglected annihilation contributions in the Wilson loop formalism of Eichten and Feinberg are defined and calculated. An annihilation time scale is introduced to discriminate the glueball contributions from true annihilation contributions to isoscalar-pseudoscalar meson states. In this formalism, it is found that there is no mixing between two quarkonium states with different quark masses t...

the burgers’ equation is a simplified form of the navier-stokes equations that very well represents their non-linear features. in this paper, numerical methods of the adomian decomposition and the modified crank – nicholson, used for solving the one-dimensional burgers’ equation, have been compared. these numerical methods have also been compared with the analytical method. in contrast to...

We estimate the power corrections (infrared renormalon contributions) to the coefficient functions for the transverse, longitudinal and asymmetric fragmentation functions in e + e − annihilation, using a method based on the analysis of one-loop Feynman graphs containing a massive gluon. The leading corrections have the expected 1/Q 2 behaviour, but the gluonic coefficients of the longitudinal a...

Positron annihilation spectroscopies are methods for direct identification of vacancy-type defects by measuring positron lifetime and Doppler broadening of annihilation radiation and providing information about open volume, concentration and atoms surrounding the defect. Both these techniques are easily applied to bulk samples. Only the Doppler broadening spectroscopy can be employed in thin ep...

ATHENA’s first detection of cold antihydrogen atoms relied on their annihilation signatures in a sophisticated particle detector. We will review the features of the ATHENA detector and its applications in trap physics. The detector for a new experiment ALPHA will have considerable challenges due to increased material thickness in the trap apparatus as well as field non-uniformity. Our studies i...

We introduce a new system-modelling representation for the interaction of particules with internal structures (hidden variable solutions). This is an improvement on Feynman diagrams that only represent points and limited information about state. The notation is able to represent key variables describing the internal states, such as phase and the three dimensional discrete field structures. The ...

A method of constructing second-quantization formalism on a set of orthonormal geminals (two-particle antisymmetric functions) is described. Instead of using an initial set of creation and annihilation operators with nontrivial commutation rules, the so-. -called ideal creation and annihilation operators, satisfying elementary Bose commutation rules, are used. The resulting Hamiltonian and an a...

A brief review is given of recent positron studies of metal and semiconductor nanocrystals. The prospects offered by positron annihilation as a sensitive method to access nanocrystal (NC) properties are described and compared with other experimental methods. The tunability of the electronic structure of nanocrystals underlies their great potential for application in many areas. Owing to their l...

We compute the cosmological background radiation of gamma rays and neutrinos due to neutralino annihilation in evolving dark matter halos, assuming the observed dark matter is comprised of thermally excited neutralinos in the MSSM. The spectrum of this gamma-ray background radiation does not show strong annihilation line features, but could amount to a significant fraction of the extragalactic ...