The magnetic field dependence of the *H spin-lattice relaxation time in ammonium persulphate shows pronounced minima near the JH magnetic resonance frequencies of 1,200 and 2,200 kHz. These are interpreted in terms of a model involving cross-relaxation between *H in the N H 4 ion and 170 in natural abundance in the S2O g_ ions, the latter having a much shorter spin-lattice relaxation time. A th...

The aqueous vanadyl ion ([VO(H(2)O)(5)](2+)) has been investigated by X-band EPR, 94 GHz W-band EPR, and ESE-ENDOR. These experiments reveal information about the hyperfine (|A(xx)| = 208.5 MHz, |A(yy)| = 208.5 MHz, |A(zz)| = 547.0 MHz), and nuclear quadrupole coupling (|e(2)qQ| = 5.6 MHz) of the (51)V nucleus. The measured nuclear quadrupole coupling parameters are compared to values determine...

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 ...

The vertical beam spread is one of the most important parameters for the high brilliance storage ring, which is represented by the coupling ratio of the horizontal and vertical beam emittances. The coupling between the horizontal and vertical betatron oscillations and the vertical dispersion with the energy spread generate the vertical beam spread, so that they should be corrected. The latter h...

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...

Several methods have been proposed for obtaining highresolution NMR spectra of half-integer spin quadrupolar nuclei (I ) /2, /2, etc.) in powdered solids. The double-rotation (DOR), dynamic-angle spinning (DAS), multiple-quantum magic-angle spinning (MQMAS), and satellite-transition magic-angle spinning (STMAS) techniques1 have attracted great interest owing to the importance of the nuclides 11...