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A. P. Martynenko

Publications and source records attributed to A. P. Martynenko.

88 records · Page 5Linked to original sources

Magnetic moment of the two-particle bound state in quantum electrodynamics

We have formulated the quasipotential method for the calculation of the relativistic and radiative corrections to the magnetic moment of the two-particle bound state in the case of particles with arbitrary spin. It is shown that the g-factors of bound particles contain $O(α^2)$ terms depending on the particle spin. Numerical values for the g-factors of the electron in the hydrogen atom and deuterium are obtained.

hep-ph↗

Hadronic vacuum polarization contribution to the Lamb shift in muonic hydrogen

The contribution of hadronic vacuum polarization to the Lamb shift in muonic hydrogen is evaluated with the account of modern experimental data on the cross section of $e^+e^-$ annihilation into hadrons. The numerical value of this contribution to the (2P-2S) shift in muonic hydrogen is equal to 10.77 $μeV$.

hep-ph↗

Proton polarizability and the Lamb shift in muonic hydrogen

The proton structure and proton polarizability corrections to the Lamb shift of electronic hydrogen and muonic hydrogen were evaluated on the basis of modern experimental data on deep inelastic structure functions. Numerical value of proton polarizability contribution to (2P-2S) Lamb shift is equal to 4.4 GHz.

hep-ph↗

Corrections of order (Zα)^6 m_e^2/m_μin the muonium fine structure

In the framework of the quasipotential method we calculate the contributions of the kind (Zα)^6m_e^2/m_μto the energy spectrum of the muonium n^3S_1 states. Numerical value of obtained correction for 2^3S_1-1^3S_1 muonium fine structure interval is equal to 0.19 MHz.

hep-ph↗

Heavy baryons in the relativistic quark model

In the framework of the relativistic quasipotential quark model the mass spectrum of baryons with two heavy quarks is calculated. The quasipotentials for interactions of two quarks and of a quark with a scalar and axial vector diquark are evaluated. The bound state masses of baryons with $J^P=\frac{1}{2}^+, \frac{3}{2}^+$ are computed.

hep-ph↗

Heavy Quark Fragmentation into Baryons in a Quark-Diquark Model

In the framework of the nonrelativistic QCD and a quark-diquark model of baryons we have obtained the fragmentation functions for heavy quark to split into spin-1/2 and spin-3/2 double heavy baryons. It was predicted the production rates as well as the shape of the energy spectra for the $cc-$ and $bc-$baryons in the region of $Z^o$ peak at LEP collider.

hep-ph↗

B_c meson production in γγcollisions and charm content of the photon

Based on photon structure function formalism we have calculated $B_c(B_c^{*})$ meson production cross section in $γγ$ collisions via partonic subprocess $cγ\to B_c(B_c^{*}) b$. It was shown that this approach gives the same results for $B_c^*(B_c)$ meson cross sections as the direct leading order QCD calculation of the subprocess $γγ\to B_c(B_c^{*})b\bar c$ at small energy. Howere, opposite to the direct QCD calculation we have obtained the increase of the $B_c(B_c^{*})$ meson cross section at large energies. We have found also additional contribution to the $B_c$ meson production via the nonperturbative fluctuations $γ\leftrightarrow J/ψ$.

hep-ph↗

Heavy Quark Fragmentation Functions In The Heavy Quark Effective Theory

We calculate fragmentation functions for a b-quark to fragment into color-singlet P-wave bound states $\bar c b$ in the Heavy Quark Effective Theory with the exact account of $O(1/m_b)$ corrections. We demonstrate an agreement of the obtained results with the corresponding calculations carried out in quantum chromodynamics.

hep-ph↗

Relativistic Effects in S-Wave Quarkonium Decay

The decay widths of S-wave quarkonia ($\etc,\etb\to \gg{~~and~~} \J,\U\to\ee$) are calculated on the basis of a quasipotential approach. The nontrivial dependence on relative quark motion of decay amplitude is taken into consideration via quarkonium wave function. It is shown that relativistic corrections may be large (10-50 %) and comparable with QCD corrections.

hep-ph↗