The 1(01)-0(00), 2(02)-1(01), and 3(03)-2(02) rotational transitions of the FCO radical are observed at 22.3, 44.5, and 66.8 GHz, respectively, using a Fourier transform millimeter-wave spectrometer with a pulsed discharge nozzle. The FCO radical is produced by discharging F(2)CO diluted in the Ar buffer gas. Twelve fine and hyperfine components for the three transitions are observed, and the e...

2014 ESR experiments have been performed on phosphorus-doped silicon with concentrations ranging from 1.9 x 1017 cm-3 to 2.8 1018 cm-3 at 1.4-4.2 K and 100 GHz. The peak shift of the central ESR line with respect to the center of the two hyperfine lines has been investigated as a function of donor concentration, temperature, and microwave power. In general, it consists of a microwave power-depe...

X-Ray irradiation at room temperature produces several paramagnetic centres in rare-earth activated K2YF5 crystals, whose thermal annealing behaviour can be linked with the occurrence of thermoluminescence (TL) glow peaks. In this paper, continuous wave (CW) and pulsed paramagnetic resonance techniques are used to study the structure of a very stable radiation-induced centre, which may be invol...

We demonstrate that electron spin relaxation in GaAs in the proximity of a Fe/MgO layer is dominated by interaction with an exchange-driven hyperfine field at temperatures below 60 K. Temperature-dependent spin-resolved optical pump-probe spectroscopy reveals a strong correlation of the electron spin relaxation with carrier freeze-out, in quantitative agreement with a theoretical interpretation...

The short-distance part of the low energy interaction of D-mesons and nucleons is investigated in the context of a quark model. The quark model is based on Coulomb gauge QCD. The model contains a confining Coulomb potential and a transverse hyperfine interaction consistent with a finite gluon propagator in the infrared. The basic mechanism for the short-distance interaction between the D-mesons...

This paper presents an explanation based on torsionally mediated proton-spin-overall-rotation interaction for the observation of doublet hyperfine splittings in some Lamb-dip sub-millimeter-wave transitions between ground-state torsion-rotation states of E symmetry in methanol. These unexpected doublet splittings, some as large as 70 kHz, were observed for rotational quantum numbers in the rang...

The formalism for the spin interactions in the front form (light-cone) is re-phrased in terms of an instant form formalism. It is shown how to unitarily transform the Brodsky-Lepage spinors to BjørkenDrell spinors and to re-phrase the so called spinor matrix in terms of the interactions one is familiar with from atomic and Dirac theory. — One retrieves the (relativistic) kinetic correction, the...

The pure rotational spectrum of the ethyl radical (C2H5) has been detected for the first time with the Fourier transform millimeter-wave spectrometer. The ethyl radical is produced by discharging the C2H5I gas diluted in Ar. The 1(01)-0(00) rotational transition of the ethyl radical is observed in the frequency range from 43,680 to 43,780 MHz. The observed spectrum shows a very complicated patt...

The spectra of baryons containing two heavy quarks test the form of the QQ potential through the spin-averaged masses and hyperfine splittings. The mass splittings in these spectra are calculated in a nonrelativistic potential model and the effects of varying the potential studied. The simple description in terms of light quark and pointlike diquark is not yet valid for realistic heavy quark ma...

So far the static properties of hadrons have been introduced in various models. The static properties of hadrons (charge radius, magnetic moment, etc.) are useful for understanding the quark structure of hadron. In this work we have introduced the hypercentral constituent quark and isospin dependent potentials. Here constituent quarks interact with each other via a potential in which we have ta...