165 research outputs found
Relativistic corrections to the pair Bc-meson production in e+e− annihilation
No full textAbstractRelativistic corrections to the pair Bc-meson production in e+e−-annihilation are calculated. We investigate a production of pair pseudoscalar, vector and pseudoscalar+vector Bc-mesons in the leading order perturbative quantum chromodynamics and relativistic quark model. Relativistic expressions of the pair production cross sections are obtained. Their numerical evaluation shows that relativistic effects in the production amplitudes and bound state wave functions three times reduce nonrelativistic results at the center-of-mass energy s=22 GeV
Radiative nonrecoil nuclear finite size corrections of order α(Zα)5 to the hyperfine splitting of S-states in muonic hydrogen
No full textAbstractOn the basis of quasipotential method in quantum electrodynamics we calculate nuclear finite size radiative corrections of order α(Zα)5 to the hyperfine structure of S-wave energy levels in muonic hydrogen and muonic deuterium. For the construction of the particle interaction operator we employ the projection operators on the particle bound states with definite spins. The calculation is performed in the infrared safe Fried–Yennie gauge. Modern experimental data on the electromagnetic form factors of the proton and deuteron are used
Hyperfine splitting of P-states in light muonic ions
No full textWe calculate hyperfine structure intervals for P–states in muonic ions of lithium, beryllium and boron. To construct the particle interaction operator in momentum space we use the tensor method ofprojection operators on states with definite quantum numbers of total atomic momentum F and total muonmomentum j. We take into account vacuum polarization, relativistic, quadruple and structure corrections of orders α4, α5 and α6. The obtained numerical values of hyperfine splittings can be used for a comparison with future experimental data
COOPERATIVE EFFECTS IN OPTICAL AND ESR SPECTROSCOPY OF NITROGEN ATOMS ISOLATED BY SOLIDIFICATED HELIUM
No full text1. E.B. Gordon, V.V. Khmelenko, A.A. Pelmenev, E.A. Popov and O.P. Pugachev, Chem. Phys. Lett. 155(3), 301-304 (1989). 2. R.E. Boltnev, E.B. Gordon, V.V. Khmelenko, A.A. Pelmenev, I.N. Kusliniskaya, M.V. Martynenko, E.A. Popov and A.V. Shestakov, Chem. Phys. 189(2), 367-382 (1994). 3. R.E. Boltnev, E.B. Gordon, V.V. Khmelenko, M.B. Martynenko, A.A. Pelmenev, E.A. Popov and A.F. Shestakov, J. Chim. Phys. 92(2), 362-383 (1995).Author Institution: Institute for Energy Problems of Chemical Physics (branch)The heavy guest particles embedded to superfluid helium can cause its . The so-called Impurity Helium Solid Phase (IHSP) being stable then up T = 7K shows the regular arrangement of the impurities with their reliable isolation by helium atoms. The feasibility of previously excited species capture to IHSP may be achieved. So metastable N(D) atoms display extremely long-lived, more than s, luminescence. Their radiative decay turns out to be caused solely by excimer-like state formation with accidentally neighbouring heavy . That was proved for N(D)-Rg pairs (Rg = Ne, Ar, Kr, Xe) by both spectra shapes and emission lifetimes observed. For N(D)- state the comparison of atomic and rovibronic spectra evidences their excimer nature as . The distances between neighbour N atoms in IHSP, 1 mm, are small enough for cooperative bulk magnetic effects appearances. ESR experiments with N(S) atoms show the effects of either magnetic alignment or spin-exchange narrowing
Hyperfine structure of S-states of muonic tritium
No full textOn the basis of quasipotential method in quantum electrodynamics we carry out a precise calculation of hyperfine splitting of S-states in muonic tritium. The one-loop and two-loop vacuum polarization corrections, relativistic effects, nuclear structure corrections in first and second orders of perturbation theory are taken into account. The contributions to hyperfine structure are obtained in integral form and calculated analytically and numerically. Obtained results for hyperfine splitting can be used for a comparison with future experimental data of CREMA collaboration
Hyperfine structure of S-states of muonic tritium
No full textOn the basis of quasipotential method in quantum electrodynamics we carry out a precise calculation of hyperfine splitting of S-states in muonic tritium. The one-loop and two-loop vacuum polarization corrections, relativistic effects, nuclear structure corrections in first and second orders of perturbation theory are taken into account. The contributions to hyperfine structure are obtained in integral form and calculated analytically and numerically. Obtained results for hyperfine splitting can be used for a comparison with future experimental data of CREMA collaboration
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