Exlusive charmed meson pair production

The experimental data of BELLE Collaboration on the exclusive charmed meson pair production in the process of monophotonic $e^+e^-$-annihilation ($e^+e^-\to \gamma^* \to D\bar D$) has been studied. It has been shown that these data is described satisfactorily in the frame work of constituent quark model. Our studies have demonstrated that the central production process $e^+e^-\to e^+e^-\gamma\gamma \to e^+e^-D\bar D +X$ and the process of monophotonic $e^+e^-$-annihilation yield comparable numbers of the charmed meson pairs.Comment: 15 pages, 7 figures, RevTeX

The relative yields of heavy hadrons as function of transverse momentum at LHC experiments

It is shown that the dependence of ratio $f_s/f_d$ could be understood within the fragmentation approach. However, the validity of fragmentation model is questionable at low $p_T$, and contributions of nonfragmentation mechanisms are possible. It is demonstrated, that the precise measurements of $p_T$ dependence of $f_s/f_d$, $f_{\Lambda_b}/f_{B}$ and analogous values as function of $p_T$ can essentially improve our understanding of heavy hadron production.At large $p_T$ a plateau is expected in $f_s/f_d$ distribution. Contrary, a plateau is not expected in $f_{B_c}/f_{B}$ distribution on $p_T$.Comment: 15 pages, 10 figures, revtex4, $f_{B_c}/f_{B}$ has been estimated for the LHCb fiducial regio

Associative production of B_c and D mesons at LHC

It is shown that the study of correlations in the associative production of B_c and D mesons at LHC allows to obtain the essential information about the B_c production mechanism.Comment: 14 pages, 10 figures. Some misprints have been removed in the last version. The reference to CTEQ pdf has been adde