arXiv subjects

Kenneth Lane

Publications and source records attributed to Kenneth Lane.

At least 55 records · Page 3Linked to original sources

arXiv2000

Technicolor 2000

This review is based on lectures on technicolor and extended technicolor presented at the Frascati Spring School in May 2000. I summarize the motivation and structure of this theory of dynamical breaking of electroweak and flavor symmetries. Particular attention is paid to the main phenomenological obstacles to this picture-flavor-changing neutral currents, precision electroweak measurements, and the large top-quark mass-and their proposed resolutions-walking technicolor and topcolor-assisted technicolor. I then discuss the signatures for technicolor and the existing and upcoming searches for them at LEP, the Tevatron Collider, and the Large Hadron Collider. The final section lists some outstanding theoretical questions.

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arXiv2000

Technicolor Signatures---Ieri, Oggi e Domani

We briefly review the basic structure of modern--day technicolor theories. We then discuss the signatures for technicolor as they were in its early days, the searches that have been recently performed at the Tevatron and LEP colliders, and the prospects for testing technicolor in Tevatron Run II and at the LHC.

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arXiv2000

Vacuum Alignment in Technicolor Theories-I. The Technifermion Sector

We have carried out numerical studies of vacuum alignment in technicolor models of electroweak and flavor symmetry breaking. The goal is to understand alignment's implications for strong and weak CP nonconservation in quark interactions. In this first part, we restrict our attention to the technifermion sector of simple models. We find several interesting phenomena, including (1) the possibility that all observable phases in the technifermions' unitary vacuum-alignment matrix are integer multiples of π/N' where N' \le N, the number of technifermion doublets, and (2) the possibility of exceptionally light pseudoGoldstone technipions.

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arXiv1999

Technicolor Signatures at the High Energy Muon Collider

I discuss high mass signatures of technicolor that would be observable at a very high energy muon collider. Most intriguing is the spectrum of spin-one technihadrons, rho_T, omega_T and A_{1T}, which may extend to 100 TeV and beyond in a walking technicolor theory.

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arXiv1999

Technihadron Production and Decay in Low-Scale Technicolor

We discuss the production and decay rates of the lightest color-singlet technihadrons, spin-one rho_T and omega_T and spin-zero pi_T, in a minimal ``straw-man'' model of low-scale techicolor. The revised rho_T and omega_T decay rates affect the technicolor searches planned for Run II of the Tevatron Collider.

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arXiv1999

Technihadron Production and Decay Rates in the Technicolor Straw Man Model

We present hadron collider production rates for the lightest color-singlet technihadrons in a simple ``straw-man'' model of low-scale technicolor. These rates are presented in a way to facilitate their encoding in PYTHIA. This document is a companion to my paper, ``Technihadron Production and Decay in Low-Scale Technicolor''.

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arXiv1998

A New Model of Topcolor-Assisted Technicolor

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 chiral symmetries except electroweak $SU(2) \otimes $U(1). These positive features depend on the outcome of vacuum alignment. The main flaw in this model is tau-lepton condensation.

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arXiv1998

Narrow Technihadron Production at the First Muon Collider

In modern technicolor models, there exist very narrow spin-zero and spin-one neutral technihadrons---$pi^0_T$, $rho^0_T$ and $omega_T$---with masses of a few 100 GeV. The large coupling of $π^0_T$ to $μ^+μ^-$, the direct coupling of $rho^0_T$ and $omega_T$ to the photon and $Z^0$, and the superb energy resolution of the First Muon Collider may make it possible to resolve these technihadrons and produce them at extraordinarily large rates.

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arXiv1998

Technicolor and the First Muon Collider

The motivations for studying dynamical scenarios of electroweak and flavor symmetry breaking are reviewed and the latest ideas, especially topcolor-assisted technicolor, are summarized. Technicolor's observable low-energy signatures are discussed. The superb energy resolution of the First Muon Collider may make it possible to resolve the extraordinarily narrow technihadrons that occur in such models--$π_T^0$, $ρ_T^0$, $ω_T$--and produce them at very large rates compared to other colliders.

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arXiv1997

Tevatron Constraints on Topcolor-Assisted Technicolor

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.

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arXiv1997

Finding Low-Scale Technicolor at Hadron Colliders

In multiscale and topcolor-assisted models of walking technicolor, relatively light spin-one technihadrons $ρ_T$ and $ω_T$ exist and are expected to decay as $ρ_T \to W π_T, Z π_T$ and $ω_T \to γπ_T$. For $M_{ρ_T} \simeq 200 GeV$ and $M_{π_T} \simeq 100 GeV$, these processes have cross sections in the picobarn range in $\bar p p$ colisions at the Tevatron and about 10 times larger at the Large Hadron Collider. We demonstrate their detectability with simulations appropriate to Run II conditions at the Tevatron.

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arXiv1997

Progress on Symmetry Breaking and Generational Mixing in Topcolor-Assisted Technicolor

Topcolor-assisted technicolor provides a dynamical explanation for electroweak and flavor symmetry breaking and for the large mass of the top quark without unnatural fine tuning. I briefly review the basics of topcolor-assisted technicolor, including major constraints and a general approach to satisfying them. The main challenge to topcolor-assisted technicolor is to generate the observed mixing between heavy and light generations while breaking the strong topcolor interactions near 1 TeV. I argue that these phenomena, as well as electroweak symmetry breaking, are intimately connected and I present a scenario for them based on nontrivial patterns of technifermion condensation. I also exhibit a class of models realizing this scenario.

hep-ph↗

arXiv1996

Non-Supersymmetric Extensions of the Standard Model

The motivations for studying dynamical scenarios of electroweak and flavor symmetry breaking are reviewed and the latest ideas, especially topcolor-assisted technicolor, are summarized. Several technicolor signatures at the Tevatron and Large Hadron Collider are described and it is emphasized that all of them are well within the reach of these colliders. (This is the written version of a plenary talk of this title at the 28th International Conference on High Energy Physics, Warsaw (1996).)

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arXiv1996

Electroweak and Flavor Dynamics at Hadron Colliders--I

This is the first of two reports cataloging the principal signatures of electroweak and flavor dynamics at $\pbarp$ and $pp$ colliders. Here, we discuss some of the signatures of dynamical elecroweak and flavor symmetry breaking. The framework for dynamical symmetry breaking we assume is technicolor, with a walking coupling $α_{TC}$, and extended technicolor. The reactions discussed occur mainly at subprocess energies $\sqrt{\hat s} \simle 1 TeV$. They include production of color-singlet and octet technirhos and their decay into pairs of technipions, longitudinal weak bosons, or jets. Technipions, in turn, decay predominantly into heavy fermions. This report will appear in the Proceedings of the 1996 DPF/DPB Summer Study on New Directions for High Energy Physics (Snowmass 96).

hep-ph↗

arXiv1996

Electroweak and Flavor Dynamics at Hadron Colliders--II

This is the second of two reports cataloging the principal signatures of electroweak and flavor dynamics at $\pbarp$ and $pp$ colliders. Here, we complete our overview of technicolor with a discussion of signatures specific to topcolor-assisted technicolor. We also review signatures of flavor dynamics associated with quark and lepton substructure. These occur in excess production rates for dijets and dileptons with high $E_T$ and high invariant mass. An important feature of these processes is that they exhibit fairly central angular and rapidity distributions. This report will appear in the Proceedings of the 1996 DPF/DPB Summer Study on New Directions for High Energy Physics (Snowmass 96).

hep-ph↗

arXiv1996

Low-Scale Technicolor at the Tevatron

In multiscale models of walking technicolor, relatively light color-singlet technipions are produced in $q \ol q$ annihilation in association with longitudinal $W$ and $Z$ bosons and with each other. The technipions decay as $\tpiz \ra b \ol b$ and $\tpip \ra c \ol b$. Their production rates are resonantly enhanced by isovector technirho vector mesons with mass $M_W + M_{\tpi} \simle M_{\tro} \simle 2 M_{\tpi}$. At the Tevatron, these associated production rates are 1--10 picobarns for $M_{\tpi} \simeq 100\,\gev$. Such a low mass technipion requires topcolor-assisted technicolor to suppress the decay $t \ra \tpip b$. Searches for $\tpi\tpi$ production will also be rewarding. Sizable rates are expected if $M_{\tro} \simge 2M_{\tpi} + 10\,\gev$. The isoscalar $ω_T$ is nearly degenerate with $\tro$ and is expected to be produced at roughly the same rate. The $ω_T$ should have the distinctive decay modes $ω_T \ra γ\tpiz$ and $Z \tpiz$.

hep-ph↗

arXiv1996

Electroweak and Flavor Dynamics at Hadron Colliders

We catalog the principal signatures of electroweak and flavor dynamics at $\pbarp$ and $pp$ colliders for use at the 1996 Snowmass Workshop on New Directions in High Energy Physics. The framework for dynamical symmetry breaking we assume is technicolor, with a walking coupling $\atc$, and extended technicolor. The reactions discussed occur mainly at subprocess energies $\rshat \simle 1\,\tev$. They include production of color-singlet and octet technirhos and their decay into pairs of technipions, longitudinal weak bosons, or jets. Technipions, in turn, decay predominantly into heavy fermions. Many of these signatures are also expected to occur in topcolor-assisted technicolor. Several particles specific to this new scenario are discussed. Additional signatures of flavor dynamics, associated with quark and lepton substructure, may be sought in excess production rates for high $E_T$ and invariant mass dijets and dileptons. An important feature of these processes is that they exhibit fairly central angular and rapidity distributions.

hep-ph↗

arXiv1996

Symmetry Breaking and Generational Mixing in Topcolor--Assisted Technicolor

Topcolor--assisted technicolor provides a dynamical explanation for electroweak and flavor symmetry breaking and for the large mass of the top quark without unnatural fine tuning. A major challenge is to generate the observed mixing between heavy and light generations while breaking the strong topcolor interactions near~$1\,\tev$. I argue that these phenomena, as well as electroweak symmetry breaking, are intimately connected and I present a scenario for them based on nontrivial patterns of technifermion condensation. I also exhibit a class of models realizing this scenario. This picture leads to a rich phenomenology, especially in hadron and lepton collider experiments in the few hundred GeV to few TeV region and in precision electroweak tests at the $Z^0$, atomic parity violation, and polarized Møller scattering.

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