In this research we described the effective Hamiltonian theory and applied this theory to the calculation of current-current (Q1,2) and QCD penguin (Q3,…,6) c quark decay rates. We calculated the decay rates of semileptonic and hadronic of charm quark in the effective Hamiltonian theory. We investigated the decay rates of D meson decays according to Spectator Quark Model (SQM) for the calculati...

Atomic energy levels are commonly evaluated assuming that the nuclear mass is infinite. In this report, we consider corrections to atomic levels associated with finite nuclear mass. These corrections are referred to as isotope shifts. We evaluate isotope shifts using many-body perturbation theory (MBPT), following the pioneering work by Mårtensson-Pendrill et al. [1, 2, 3, 4, 5, 6, 7, 8, 9]. We...

2014 The quantum Boltzmann equation governing the evolution of the one-body internal density matrix of an atomic hydrogen (or alkali) gas is established. Indistinguishability of both nuclei and electrons explains the presence in the collision term of a large number (eleven) of « exchange cross sections ». The different collision terms fall into two categories : these which contribute to the dam...

We study a generalized cold atom Bose-Hubbard model, where the periodic optical potential is formed by a cavity field with quantum properties. On the one hand, the common coupling of all atoms to the same mode introduces cavity-mediated long-range atom-atom interactions, and, on the other hand, atomic backaction on the field introduces atom-field entanglement. This modifies the properties of th...

We present a computer program and underlying model to calculate the electric susceptibility of a gas, which is essential to predict its absorptive and dispersive properties. Our program focuses on alkali-metal vapours where we use a matrix representation of the atomic Hamiltonian in the completely uncoupled basis in order to calculate transition frequencies and strengths. The program calculates...

Parity-nonconserving (PNC) atomic effects originate from the electroweak interaction of atomic electrons with the nucleus via Z-boson exchange. Comparing experimental results with theoretical predictions of the standard model allows to search for ”new physics” beyond the standard model (e.g., a second Z-boson or new fermions) [1]. In the case of neutral atoms here is the discrepancy between the...

We derive the interaction Hamiltonian of a Laguerre-Gaussian beam with a simple atomic system, under the assumption of a small spread of the center of mass wave function in comparison with the waist of the Laguerre-Gaussian beam. The center of mass motion of the atomic system is taken into account. Using the properties of regular spherical harmonics the internal and center of mass coordinates a...