Heavy Quark Phenomenology In E~+e~-/γγ Collision At High Energy

Heavy quark physics plays an important role in testing the Standard Model and searching for new physics. The thesis is concerned on the problems which relate with heavy quark phenomenology in e~+ e~-/γγcollision at high energy.In the annihilation of e~+e~-, the color connection of final parton system plays a crucial role to set the "surface" between the Perturbative Quantum Chromodynamics(PQCD) phase and the hadronization one. Different color connection may lead to different hadronization states. The investigation on color connection of final parton system is helpful for understanding the mechanism of hadronization. In this thesis, we investigate the color connection and diquark fragmentation in e~+e~-→c(?)q(?)→h's process. A special case is that two quarks in colour state 3~* attract each other and form a "diquark" when their invariant mass is small enough, and similarly two antiquarks form an antidiquark. For this decomposition, the diquark fragmentation is employed based on Pythia. We investigate the production of final state particles, e.g. (?) . The momentum spectrum of (?) and (?) (?) correlation are calculated. It is found that the predictions for (?) production including the diquark pair production will not conflict with the available data and a portion of diquark fragmentation events is favored in high energy e~+e~- reaction.The investigation of doubly heavy baryon production is helpful for understanding both the production mechanism and the color connection of final state partons. In this thesis, we investigate the production of doubly heavy baryon at photon collider, e.g. (?),(?). The cross sections of (?) and (?) are calculated at (?)=500GeV in the e~+e~- CMS. Additionally, taking (?) as an example, we give the predictions for the distributions of cosθ, x etc.. Here,θand x are defined in e~+e~- CMS, whereθis the angle between the moving direction of (?) and that of the beam, x = 2E/(?) and E the energy of (?). One can find that the contributions from the color sextet diquark and that from the color triplet one are important for the production of doubly heavy baryon. The production rate of (?) can be increased with appropriate choice of initial beam polarizations.Top quark is the heaviest fermion as far as we know. Its life is so short that it can not be affected by the hadronization, which makes it be a free quark. Therefore, top quark physics will play an important role in finding new physics beyond the Standard Model. If unparticle exists, the production of top quark pair will be affected by its effects. We investigated the unparticle effects on top quark pair production at photon collider in this thesis. It is found that the unparticle effects depend on the unparticle spin and its scale dimension d_u. Distributions of t(?) invariant mass and that for transverse momentum of top quark with respect to Standard Model and unparticle production are predicted. An odd valley with scalar unparticle contribution appears for some values of d_u, which is due to the big cancellation between the contribution from SM and that from unparticle. This character may be used to study the properties of scalar unparticle. Our investigations also show that scalar unparticle may play a significant role in t(?) production at photon collider if it exists.