35141469
Flavor-changing Z decay in the one generation technicolor models.
The flavor-changing decay Z\ensuremath{\rightarrow}bs\ifmmode\bar\else\textasciimacron\fi{}(b\ifmmode\bar\else\textasciimacron\fi{}s) induced through pseudo Goldstone bosons (PGB's) is calculated in two kinds of one generation technicolor models (OGTM's). (a) For model I, we find that an interesting branching ratio B(Z\ensuremath{\rightarrow}bs\ifmmode\bar\else\textasciimacron\fi{}+b\ifmmode\bar\else\textasciimacron\fi{}s)\ensuremath{\sim}${10}^{\mathrm{\ensuremath{-}}6}$ can be obtained for particular choices of the parameters; such a magnitude of the order of the branching ratio is at the border of being detectable. (b) For model II, the PGB contributions can strongly enhance the branching ratio B(Z\ensuremath{\rightarrow}bs\ifmmode\bar\else\textasciimacron\fi{}+b\ifmmode\bar\else\textasciimacron\fi{}s). With the current experimental limit on the branching ratios of rare Z decay, the model-dependent bounds on the mass of the color octet pseudo Goldstone bosons can be derived. As will be seen, the decay Z\ensuremath{\rightarrow}bs\ifmmode\bar\else\textasciimacron\fi{}(b\ifmmode\bar\else\textasciimacron\fi{}s) may provide a unique window to study the TC theory.
118443717
The flavor-changing top-charm associated productions at ILC in littlest Higgs model with T parity
The littlest Higgs model with T-parity (LHT) has new flavor-changing (FC) couplings with the Standard Model (SM) quarks, which do not suffer strong constraints from electroweak precision data. So these FC interactions may enhance the cross sections of some flavor-changing neutral-current (FCNC) processes. In this work, we study the FC top-charm associated productions via $e^{-}\gamma$ collision at the ILC. We find that the cross sections are sensitive to the mirror quark masses. With reasonable values of the parameters, the cross sections may reach the detectable level and provide useful information about the relevant parameters in the LHT model, especially setting an upper limit on the mirror quark masses.
123435703
UNIFIED MODEL OF METACOLOR INTERACTION
Unified composite model in which the metacolor symmetry group and the standard model group are embedded in a single group of the SU(N) type and unified above a certain energy scale are constructed. Such unification scheme provides constraints to the composite model building. The proposed models are analyzed in terms of the complementarity principle to show that they satisfy the physics Higgs phase criterion. In order to obtain a metacolor scale of the order of a few tens TeV, the rank of the unification group is restricted.
204187229
A CONFINING SU(4) X SU(4) COMPOSITE MODEL OF THE WEAK INTERACTIONS. (IN CHINESE)
120681113
Production of the lightest neutral technipion at the First Muon Collider
In the framework of the topcolour-assisted multiscale technicolour (TOPCMTC) models, we discuss the s-channel resonance production of the lightest neutral technipion P0 at the First Muon Collider (FMC). Our calculation results show that the effective cross section is very large and at least larger than that of the standard model Higgs boson h0 by one order of magnitude. Thus, the FMC offers an opportunity for detecting the technipions and testing various technicolour models.
5505221
The rare top decay t → cg in topcolor assisted technicolor models
In the framework of topcolor-assisted technicolor(TC2) models, we calculate the contributions of flavor changing scalar couplings involved the neutral top-pion � 0 and top-Higgs h 0 to the branching ratio Br(t −→ cg). We find that the value of Br(t −→ cg) can reach 1 × 10 3 with reasonable values of the parameters in TC2 models, which may be testable in the future experiments.
14845325
Massive-scalar absorption by extremal p-branes
Abstract We study the absorption probability of minimally-coupled massive scalars by extremal p -branes. In particular, we find that the massive scalar wave equation under the self-dual string background has the same form as the massless scalar wave equation under the dyonic string background. Thus it can be cast into the form of a modified Mathieu equation and solved exactly. Another example that we can solve exactly is that of the D =4 two-charge black hole with equal charges, for which we obtain the closed-form absorption probability. We also obtain the leading-order absorption probabilities for D3-, M2- and M5-branes.