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Related papers: Reexamination of the Constraint on Topcolor-Assist…

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Using precision electroweak data, we put limits on ``natural'' top-color assisted technicolor models. Generically the new $U(1)$ gauge bosons in these models must have masses larger than roughly 2 TeV, although in certain (seemingly…

High Energy Physics - Phenomenology · Physics 2011-01-13 R. S. Chivukula , J. Terning

We identify and compute the main corrections to $R_b$ in Topcolor theories. They are due to the top-pions, the pseudo-Goldstone bosons associated with the chiral symmetry breaking responsible for the top quark mass, and amount to -(1-4)%,…

High Energy Physics - Phenomenology · Physics 2009-10-30 Gustavo Burdman , Dimitris Kominis

Conventional technicolor models with light charged technipions ($\pi ^{\pm} _T$) lead to an unacceptably large contribution to $t\ra {\pi ^+_T} b$ decay rate. Topcolor-assisted technicolor models also have additional PGBs called top-pions…

High Energy Physics - Phenomenology · Physics 2009-10-30 B. Balaji

We use the LEP/SLD data to place constraints on Topcolor Assisted Technicolor Models. We find that due to a large negative shift in R_b induced by charged top-pion exchange, it is difficult to make the models compatible with experiment.

High Energy Physics - Phenomenology · Physics 2016-08-25 Will Loinaz , Tatsu Takeuchi

We argue that extended technicolor augmented with topcolor requires that all mixing between the third and the first two quark generations resides in the mixing matrix of left-handed down quarks. Then, the anti-B_d--B_d mixing that occurs in…

High Energy Physics - Phenomenology · Physics 2009-10-31 Gustavo Burdman , Kenneth Lane , Tonguc Rador

In this paper we calculate the technicolor correction to the production of a charged top pion in association with a W boson via b\bar{b} annihilation at the CERN Large Hadron Collider in the context of the topcolor assisted technicolor…

High Energy Physics - Phenomenology · Physics 2014-11-21 Jinshu Huang , Qunna Pan , Taiping Song , Gongru Lu

A condensate, $\overline{t}t$, arising from $O(TeV)$ scale ``topcolor,'' in addition to technicolor (and ETC) may naturally explain the gauge hierarchy, the large top quark mass, and contains a rich system of testable consequences. A…

High Energy Physics - Phenomenology · Physics 2011-01-27 Christopher T. Hill

In the framework of topcolor-assisted technicolor model we calculate the contributions from the pseudo Goldstone bosons and new gauge bosons to $e^+e^- \to t\bar{t}$. We find that, for reasonable ranges of the parameters, the pseudo…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. Hunag , Z. Xiong , G. Lu

We study the Yukawa corrections to the gamma gamma --> b\bar{b} corss section in the topcolor assisted technicolor models at the photon-photon colliders. We find that, for the favorable parameters, the relative corrections from pseudo…

High Energy Physics - Phenomenology · Physics 2008-11-07 Jin-Shu Huang , Gong-Ru Lu

Extended technicolor (ETC) theories typically require ETC gauge bosons lighter than of order 1 TeV, to perturbatively generate the $t$ quark mass. We point out that explicit models of $t-b$ mass splitting also typically contain additional…

High Energy Physics - Phenomenology · Physics 2009-10-28 Thomas Appelquist , Nick Evans , Stephen B. Selipsky

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…

High Energy Physics - Phenomenology · Physics 2008-12-25 Hong-Yi Zhou , Yu-Ping Kuang , Chong-Xing Yue , Hua Wang , Gong-Ru Lu

We study the constraints on models of topcolor-assisted technicolor arising from measurements of high-$E_T$ jets and high-mass lepton pairs at the Tevatron collider. Existing data can eliminate models that have appeared in the literature.

High Energy Physics - Phenomenology · Physics 2009-10-30 Yumian Su , Gian Franco Bonini , Kenneth Lane

LEP precision measurements of the $Zb\bar{b}$ vertex coupling are sufficiently accurate to see the non-oblique corrections from the heavy gauge boson responsible for the large top mass in standard extended tecnicolour models. If the ETC…

High Energy Physics - Phenomenology · Physics 2009-10-28 Nick Evans

We calculate the contributions to the rare decays $B \to X_{s,d} \nu \bar \nu$ and $B_{s,d} \to l^+l^-$ from one-loop $Z^0$-penguin diagrams in the framework of Topcolor-assisted Technicolor Model. Within the parameter space, we find that:…

High Energy Physics - Phenomenology · Physics 2011-03-23 Xiao Zhenjun , Jia Liqun , Lü Linxia , Lu Gongru

In the framework of topcolor-assisted technicolor(TC2) models, we calculate the contributions of flavor changing scalar couplings involved the neutral top-pion $\pi_{t}^{0}$ and top-Higgs $h_{t}^{0}$ to the branching ratio…

High Energy Physics - Phenomenology · Physics 2009-11-07 Chongxing Yue , Gongru Lu , Guoli Liu , Qingjun Xu

We calculate the rates for lepton number violating processes via the exchange of the Z' boson occuring in top-color assisted technicolor. The current experimental limits on muon electron conversion in Ti nuclei allow for a mass of the new…

High Energy Physics - Phenomenology · Physics 2016-08-25 Tonguc Rador

The latest LHC data suggest an intriguing excess at $m_{\gamma\gamma} = 750$ GeV which apparently requires an explanation from the beyond standard model physics. In this note we explore the possibility for this signal to arise from a…

High Energy Physics - Phenomenology · Physics 2016-06-14 Yu-Chen Guo , Chong-Xing Yue , Zhen-hua Zhao

The new gauge boson $Z^{\prime}$ predicted by the strong top dynamical symmetry breaking models has significant contributions to the lepton flavor changing process $\mu\longrightarrow 3e $. We consider the bound on the mass of the new gauge…

High Energy Physics - Phenomenology · Physics 2009-10-31 Chongxing Yue , Guoli Liu , Jiantao Li

I present a model of topcolor-assisted technicolor that can have topcolor breaking of the desired pattern, hard masses for all quarks and leptons, mixing among the heavy and light generations, and explicit breaking of all technifermion…

High Energy Physics - Phenomenology · Physics 2009-10-31 Kenneth Lane

Recent work by Burdman, Lane, and Rador has shown that B-meson mixing places stringent lower bounds on the masses of topgluons and Z' bosons in classic topcolor-assisted technicolor (TC2) models. This paper finds analogous limits on the Z'…

High Energy Physics - Phenomenology · Physics 2009-11-07 Elizabeth H. Simmons
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