Superconductivity in the C32 compounds CaAlSi and SrAlSi is investigated by heat capacity measurements as well as high-pressure ac-susceptibility experiments. The heat capacity in the superconducting state is well explained by the BCS theory for weak ~SrAlSi! and enhanced coupling strength ~CaAlSi!. The magnitudes of the superconducting gaps are estimated as 2.7 meV ~CaAlSi! and 1.4 meV ~SrAlSi...

A method of calculation of vibronic or electron-phonon coupling constant is presented for a Jahn-Teller molecule, cyclopentadienyl radical. It is pointed out that symmetry breaking at degenerate point and violation of Hellmann-Feynman theorem occur in the calculations based on a single Slater determinant. In order to overcome these difficulties, the electronic wave functions are calculated usin...

We use Monte Carlo simulations to obtain an improved lattice measurement of the critical coupling constant [ λ/μ ] crit for the continuum (1 + 1)-dimensional (λ/4)φ theory. We find that the critical coupling constant depends logarithmically on the lattice coupling, resulting in a continuum value of [ λ/μ ] crit = 10.8 −.05, in considerable disagreement with the previously reported [ λ/μ ] crit ...

density functional theory (dft) based calculations have been performed to examine the relaxations of tautomers of 4–hydroxy–6–methylpyridin–2(1h)–one (mpo), as a representative of pyridinone derivatives, at the fullerene (c60) surfaces. optimized molecular properties including energies, dipole moments and atomic scale quadrupole coupling constants (cq) have been evaluated to investigate the str...

We calculate the π∆∆ coupling gπ0∆++∆++ using light cone QCD sum rule. Our result is gπ0∆++∆++ = (11.8 ± 2.0). We compare various model predictions. PACS numbers: 12.39.Fe, 14.20.Gk The π∆∆ coupling constant g1, like the nucleon axial charge gA, is a basic parameter which enters the loop calculation in all processes involved with delta resonance [1] in chiral perturbation theory. Unfortunately ...

In this talk a search for the single production of top quarks performed at the H1 experiment is presented. No evidence for anomalous top production via FCNC processes is found and limits on the anomalous magnetic coupling constant κtuγ are given.

There is a convincing experimental evidence that neutrinos are massive. Therefore we investigate the influence of the neutrino masses on the unification of gauge and Yukawa couplings in the framework of the Minimal Supersymmetric Standard Model. We estimate the contribution of the neutrino Yukawa coupling to the gauge and Yukawa coupling unification. We find that in the case of the gauge coupli...