This dissertation is devoted to the study of new class of central exclusive processes - diffractive production of heavy quarkonium and besides to the study iНастоящая диссертация посвящена исследованию нового класса центральных эксклюзивных процессов -- диффракционного рождения тяжелых кваркониев, а также изучению и развитию общих теоретических методов и механизмов, лежащих в основе динамики диффракционных процессов.

Подход $k_{\perp}$-факторизации последовательно применяется к инклюзивному и эксклюзивному диффракционному процессам рождения хиггсовского бозона в адронных соударениях на LHC и Tevatron. Оценена роль глюонных виртуальностей как в амплитуде и форм факторах, так и в наблюдаемых, в частности, в соответствующих дифференциальных и полных сечениях.

Рассмотрены диффракционные процессы рождения легкого псевдоскалярного $\eta'$-мезона и тяжелых кваркониев на примере скалярного $\chi_c(0^+)$, аксиально-векторного $\chi_c(1^+)$ и тензорного $\chi_c(2^+)$ чармониев. Для различных глюонных распределений получены соответствующие предсказания диффенциальных и полных сечений в механизмах двойной диффракции и померонном обмене, а также оценен вклад $\gamma^*\gamma^*$ (КЭД) механизма, исследованы источники теоретических неопределенностей. В случае рождения $\chi_c(1^+)$ показано нарушение теоремы Ландау-Янга глюонными виртуальностями, детально исследованы поляризационные эффекты и их роль на угловое распределение выходящего $J/\psi$.

We discuss the method of QCD sum rules with non-local condensate. We showed that minimal Gauss model of quark and quark-gluon condensate non-locality violates transversality of two vector currents correlator. We propose the improved Gauss model of non-local condensate which is in agreement wich QCD motion equations in which this violation of gauge invariance is minimized.

We obtained more accurate conformal moments of pion distribution amplitude in new model of QCD vacuum and allowed region of values for Gegenbauer coefficients $a_2$ and $a_4$ of pion distribution amplitudes. We present the results of calculations of electomagnetic form factor of the pion in Euclidian region $1-10 GeV^2$ within QCD sum rule approach with non-local condensate in minimal and improved models.

We evaluate the effects of Fremi sphere occupation by quarks which are considered as quasi-particles. This picture corresponds to the bag model where filled states look like the natural matherial to build up the baryons.

We investigate mesonic correlation function of the model with delta-like form factors in momentum space and studied their analytical continuation from Euclidian space into pseudo-Euclidian. We showed that besides the singular character of mean energy of the system and quark condensate the mesonic observables are finite and comparable with the experimental data by the energy scale. The specific of the model is the bounded states at any quark momenta.

Three processes:

• $K^+ \to \pi^+ \pi^- e^+ \nu_e(\gamma)$,
• $\chi \bar \chi \to e^+ e^- \gamma(\gamma)$,
• $t \to b W^+ \to b e^+ \nu_e (\gamma)$ and $t \to b H^+ \to b \tau^+ \nu_\tau (\gamma)$,

and radiative corrections to them are considered. The results of explicit calculations of radiative corrections in lowest order of perturbation theory are in agreement with Drell-Yan form of width (cross section) of processes with the splitting function (structure function) of the light lepton.

A generalization in leading and next-to-leading approximation is given.

In first process the details of final state interaction in $\pi^+\pi^-$ system (such as Sakharov factor) and the phases of $\pi^+\pi^- \to \pi^0\pi^0,\pi^+\pi^-$ rescattering are discussed.

Spectra of lepton and neutrino in top quark decay through $W^+$ or $H^+$ intermediate state are considered.

The presence of dark matter consisting from slow moving superparticles can manifest itself through QED annihilation channels.

We calculated the cross sections of scalar mesons $f_0(980)$, $a_0(980)$ and $\sigma(600)$ production in electron-positron colliders. We used two photon decay width of scalar mesons which was obtained in Nambu-Jona-Lasinio model with quark and mesons loops.

We found out the region of applicability of fragmentational description in production of heavy mesons, double-heavy meson and baryons. The cross sections are evaluated.

Light cone wave functions which parameterize the process of hadronization are important object needed to calculate the amplitudes of hard exclusive processes of hadron production. The talk will consider different wave functions of $S$- and $P$-waves of charmonium. Non-relativistic nature of these charmoniums allows one to get a series of interesting properties of wave functions and to build realistic models for wave functions of these mesons. We also will consider some hard exclusive processes of charmonium production which allow usage of these models.

We consider the process of Higgs boson production in $pp$-collisions ($pp \to ppH$) with subsequent Higgs boson decay $H \to ZZ \to (e^+ \nu_e) (e^- \bar\nu_e)$. The distributions over energy fractions and scattering angles of Higgs boson are given and besides the evaluation of the total cross section for Tevatron, RHIC and LHC setups are presented.

We discuss backgrounds in the case of Higgs boson signal in the channel $H \to e^+ e^- + X$ of the decay into two different leptons.

As a characteristic signal of Higgs boson production we propose the channel: $$H \to Z Z \to (e^+ \nu_e)(e^- \bar\nu_e),$$ where one should measure lepton energy fractions and the angle between the directions of two outgoing leptons in the reference frame where Higgs boson is at rest.

In 1999 in the "Higgs handbook" it was shown that the channel $H\to ZZ\to 4e$ of decay can be found at the level of significance $5\sigma$ at the total luminosity $L \approx 100 fb^{-1}$.

We considered two-photon decays of isoscalar scalar mesons $\sigma(600)$, $f_0(980)$ and $a_0(980)$. The radiative decay width of scalar mesons $f_0(980)$ and $a_0(980)$ into $\rho(\omega)\gamma$ mesons was calculated. This results were used for the description of $e^+e^- \to SV$ processes where $S = a_0, f_0, \sigma$, $V = \rho, \omega$. The calculations was done within local Nambu-Jona-Lasinio model.

We obtained cross sections differential over recoil momentum and total cross sections for the processes of photon collision with the lepton and heavy hadron with the production of scalar ($\sigma(600)$, $f_0(980)$, $a_0(980)$) and pseudoscalar ($\pi^0$, $\eta$, $\eta'$) mesons. The calculations was done within local Nambu-Jona-Lasinio model.