arXiv subjects

Chong-Xing Yue

Publications and source records attributed to Chong-Xing Yue.

98 records · Page 6Linked to original sources

arXiv2005

Search for the vector-like top quark $T$ at the future linac-ring type $ep$ collider

The little Higgs models typically contain a new vector-like top quark $T$, which plays a key role in breaking the electroweak symmetry. In the context of the littlest Higgs (LH) model, we study single production of this kind of new particle via the process $ep\to eb\to ν_{e}T$ in the future linac-ring type $ep$ collider (LC$\bigotimes LHC$). We find that the production cross section is in the range of $1.2\times 10^{-4}$-- 0.48 $pb$ at the $LC\bigotimes LHC$ with $\sqrt{s}=3.7$ $TeV$.

hep-ph↗

arXiv2005

New gauge bosons from the littlest Higgs model and the process $e^{+}e^{-}\to t\bar{t}$

In the context of the littlest Higgs$(LH)$ model, we study the process $ e^{+}e^{-}\to t\bar{t}$. We find that the new gauge bosons $Z_{H}$ and $B_{H}$ can produce significant correction effects on this process, which can be further enhanced by the suitably polarized beams. In most of the parameter space preferred by the electroweak precision data, the absolute value of the relative correction parameter $R_{B_{H}}$ is larger than 5%. As long as $1TeV\leq M_{Z_{H}}\leq 1.5TeV$ and $0.3\leq c\leq 0.5,$ the absolute value of the relative correction parameter $R_{Z_{H}}$ is larger than 5%. With reasonable values of the parameters of the $LH$ model, the possible signals of the new gauge bosons $B_{H}$ and $Z_{H}$ can be detected via the process $ e^{+}e^{-} \to t\bar{t}$ in the future $LC$ experiments with the c.m. energy $\sqrt{S}=800GeV$. $B_{H}$ exchange and $Z_{H}$ exchange can generate significantly corrections to the forward-backward asymmetry $A_{FB}(t\bar{t})$ only in small part of the parameter space.

hep-ph↗

arXiv2005

Flavor changing scalar couplings and $tγ(Z)$ production at hadron colliders

We calculate the contributions of the flavor changing scalar ($FCS$) couplings arised from topcolor-assisted technicolor ($TC2$) models at tree-level to the $tγ$ and $tZ$ production at the Tevatron and $LHC$ experiments. We find that the production cross sections are very small at the Tevatron with $\sqrt{s}=1.96TeV$, which is smaller than 5 fb in most of the parameter space of $TC2$ models. However, the virtual effects of the $FCS$ couplings on the $tγ(Z)$ production can be easily detected at the $LHC$ with $\sqrt{s}=14TeV$ via the final state $γl\barνb$ ($l^{+}l^{-}l\barνb$).

hep-ph↗

arXiv1998

Testing Technicolor Models via Top Quark Pair Production in High Energy Photon Collisions

Pseudo-Goldstone boson contributions to $t\bar{t}$ production rates in technicolor models with and without topcolor at the $\sqrt{s}=0.5 and 1.5$ TeV photon colliders and hadron colliders are reviewed. For reasonable ranges of the parameters, the contributions are large enough to be experimentally observable. Models with topcolor, without topcolor and the MSSM with $\tanβ\geq 1$ can be experimentally distinguished.

hep-ph↗

arXiv1997

Testing Technicolor Models in Top Quark Pair Production at High Energy Photon Colliders

We study pseudo-Goldstone boson corrections to top quark pair production rates in technicolor models with and without topcolor at the E=0.5 teV and 1.5 TeV photon colliders. We find that, for reasonable ranges of the parameters, the corrections are large enough to be observable, and the corrections in models with topcolor are considerably larger than those in models without topcolor, and they are all significantly larger than the corresponding corrections in the minimal supersymmetric standard model (MSSM) with tan(beta) of the order of 1. So that the two kinds of technicolor models and the MSSM with tan(beta) of the order of 1 can be experimentally distinguished.

hep-ph↗

arXiv1996

t anti-t Production Rates at the Tevatron and the LHC in Topcolor- Assisted Multiscale Technicolor Models

We study the contributions of the neutral pseudo Goldstone bosons (technipions and top-pions) to the t anti-t production cross sections at the Tevatron and the LHC in topcolor-assisted multiscale technicolor (TOPCMTC) models via the gluon-gluon fusion process from the loop-level couplings between the pseudo Goldstone bosons and the gluons. The MRS set A' parton distributions are used in the calculation. It is shown that the new CDF datum on the t anti-t production cross section gives constraints on the parameters in the TOPCMTC models. With reasonable values of the parameters in TOPCMTC models, the cross section at the Tevatron is larger than that predicted by the standard model, and is consistent with the new CDF data. The enhancement of the cross section and the resonance peaks at the LHC are more significant, so that it is testable in future experiments.

hep-ph↗

arXiv1995

Multiscale Technicolor and the Zbb-bar Vertex

We estimate the correction to the Zbb-bar vertex arising from the exchanges of the sideways extended technicolor (ETC) boson and the flavor-diagonal ETC boson in the multiscale walking technicolor model. The obtained result is too large to explain the present data. However, if we introduce a new self- interaction for the top quark to induce the top quark condensate serving as the origin of the large top quark mass, the corrected R_b=Gamma_b/Gamma_h can be consistent with the recent LEP data. The corresponding correction to R_c=Gamma_c/Gamma_h is shown to be negligibly small.

hep-ph↗

arXiv1995

Radiative Corrections to the Z-b-(anti-b) and Z-tau-(anti-tau) Vertices in a Realistic One-Family Extended Technicolor Model

In a realistic effective one-family extended technicolor(ETC) model without exact custodial symmetry, we calculate the one-loop corrections to the Z-b-(anti-b) and Z-tau-(anti-tau)vertices from the sideways and diagonal ETC bosons exchange. The result shows that both the Z-->b+anti-b partial width (and the branching ratio) and the tau polarization asymmetry parameter A_tau are enhanced by the corrections and are in agreement with the present experimental data.

hep-ph↗