Showing papers on "Electroweak interaction published in 2002"
CERN1
TL;DR: SOFTSUSY as discussed by the authors is a program which accurately calculates the spectrum of superparticles in the Minimal Supersymmetric Standard Model (MSSM), solving the renormalisation group equations with theoretical constraints on soft supersymmetry breaking terms provided by the user.
1,015 citations
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TL;DR: In this paper, an economical theory of natural electroweak symmetry breaking was proposed, which stabilizes the electroweak scale with a naturally light Higgs and weakly coupled new physics at TeV energies.
Abstract: We present an economical theory of natural electroweak symmetry breaking, generalizing an approach based on deconstruction. This theory is the smallest extension of the Standard Model to date that stabilizes the electroweak scale with a naturally light Higgs and weakly coupled new physics at TeV energies. The Higgs is one of a set of pseudo Goldstone bosons in an SU(5)/SO(5) nonlinear sigma model. The symmetry breaking scale f is around a TeV, with the cutoff Λ4πf ~ 10 TeV. A single electroweak doublet, the `little Higgs', is automatically much lighter than the other pseudo Goldstone bosons. The quartic self-coupling for the little Higgs is generated by the gauge and Yukawa interactions with a natural size (g2, λt2), while the top Yukawa coupling generates a negative mass squared triggering electroweak symmetry breaking. Beneath the TeV scale the effective theory is simply the minimal Standard Model. The new particle content at TeV energies consists of one set of spin one bosons with the same quantum numbers as the electroweak gauge bosons, an electroweak singlet quark with charge 2/3, and an electroweak triplet scalar. One loop quadratically divergent corrections to the Higgs mass are cancelled by interactions with these additional particles.
1,004 citations
TL;DR: In this article, the authors presented the minimal theory space model of electroweak symmetry breaking, with two sites and four link fields, and the minimal set of fermions, which is the first alternative to weak-scale supersymmetry with naturally light Higgs fields.
Abstract: Recently a new class of theories of electroweak symmetry breaking have been constructed. These models, based on deconstruction and the physics of theory space, provide the first alternative to weak-scale supersymmetry with naturally light Higgs fields and perturbative new physics at the TeV scale. The Higgs is light because it is a pseudo-Goldstone boson, and the quadratically divergent contributions to the Higgs mass are cancelled by new TeV scale ``partners'' of the same statistics. In this paper we present the minimal theory space model of electroweak symmetry breaking, with two sites and four link fields, and the minimal set of fermions. There are very few parameters and degrees of freedom beyond the Standard Model. Below a TeV, we have the Standard Model with two light Higgs doublets, and an additional complex scalar weak triplet and singlet. At the TeV scale, the new particles that cancel the 1-loop quadratic divergences in the Higgs mass are revealed. The entire Higgs potential needed for electroweak symmetry breaking - the quartic couplings as well as the familiar negative mass squared - can be generated by the top Yukawa coupling, providing a novel link between the physics of flavor and electroweak symmetry breaking.
612 citations
TL;DR: In this paper, the authors presented the minimal theory space model of electroweak symmetry breaking, with two sites and four link fields, and the minimal set of fermions, which is the first alternative to weak-scale supersymmetry with naturally light Higgs fields.
Abstract: Recently a new class of theories of electroweak symmetry breaking have been constructed. These models, based on deconstruction and the physics of theory space, provide the first alternative to weak-scale supersymmetry with naturally light Higgs fields and perturbative new physics at the TeV scale. The Higgs is light because it is a pseudo-Goldstone boson, and the quadratically divergent contributions to the Higgs mass are cancelled by new TeV scale ``partners'' of the {\em same} statistics. In this paper we present the minimal theory space model of electroweak symmetry breaking, with two sites and four link fields, and the minimal set of fermions. There are very few parameters and degrees of freedom beyond the Standard Model. Below a TeV, we have the Standard Model with two light Higgs doublets, and an additional complex scalar weak triplet and singlet. At the TeV scale, the new particles that cancel the 1-loop quadratic divergences in the Higgs mass are revealed. The entire Higgs potential needed for electroweak symmetry breaking--the quartic couplings as well as the familiar negative mass squared--can be generated by the top Yukawa coupling, providing a novel link between the physics of flavor and electroweak symmetry breaking.
465 citations
TL;DR: In this article, the NuTeV Collaboration has extracted the electroweak parameter sin 2 θ W from the measurement of the ratios of neutral current to charged current v and ν cross sections.
Abstract: The NuTeV Collaboration has extracted the electroweak parameter sin 2 θ W from the measurement of the ratios of neutral current to charged current v and ν cross sections. Our value, sin 2 θ W ( o n - s h e l l ) = 0.2277 ′0.0013(stat) ′ 0.0009(syst), is 3 standard deviations above the standard model prediction. We also present a model independent analysis of the same data in terms of neutral-current quark couplings.
462 citations
TL;DR: In this article, the standard model on a non-commutative space was considered and the action in the noncommutativity parameter was extended to include the leading order action, and the most striking features were couplings between quarks, gluons and electroweak bosons and new vertices in the charged and neutral currents.
Abstract: We consider the standard model on a non-commutative space and expand the action in the non-commutativity parameter $\theta^{\mu
u}$
. No new particles are introduced; the structure group is $SU(3)\times SU(2)\times U(1)$
. We derive the leading order action. At zeroth order the action coincides with the ordinary standard model. At leading order in $\theta^{\mu
u}$
we find new vertices which are absent in the standard model on commutative space-time. The most striking features are couplings between quarks, gluons and electroweak bosons and many new vertices in the charged and neutral currents. We find that parity is violated in non-commutative QCD. The Higgs mechanism can be applied. QED is not deformed in the minimal version of the NCSM to the order considered.
329 citations
01 Jan 2002
TL;DR: In this paper, a combination of published and preliminary electroweak results from the four LEP collaborations and the SLD collaboration which were prepared for the 1997 summer conferences are presented. And the results are compared with precise electroweak measurements from other experiments.
Abstract: This note presents a combination of published and preliminary electroweak results from the four LEP collaborations and the SLD collaboration which were prepared for the 1997 summer conferences. Averages are derived for hadronic and leptonic cross-sections, the leptonic forwardbackward asymmetries, the polarisation asymmetries, the bb and cc partial widths and forwardbackward asymmetries and the qq charge asymmetry. The major changes with respect to results presented last year are updated results of ALR from SLD, and the inclusion of the rst direct measurements of the W mass and triple-gauge-boson couplings performed at LEP. The results are compared with precise electroweak measurements from other experiments. The parameters of the Standard Model are evaluated, rst using the combined LEP electroweak measurements, and then using the full set of electroweak results. The LEP Collaborations each take responsibility for the preliminary data of their own experiment. yD. Abbaneo, J. Alcaraz, P. Antilogus, T. Behnke, B. Bertucci, A. Blondel, C. Burgard, R. Clare, P.E.L. Clarke, S. Dutta, M. Elsing, R. Faccini, D. Fassouliotis, M.W. Gr unewald, A. Gurtu, K. Hamacher, J.B. Hansen, R.W.L. Jones, P. de Jong, T. Kawamoto, M. Kobel, E. Lan con, W. Lohmann, C. Mariotti, M. Martinez, C. Matteuzzi, M.N. Minard, K. Monig, P. Molnar, A. Nippe, S. Olshevski, Ch. Paus, M. Pepe-Altarelli, S. Petzold, B. Pietrzyk, G. Quast, D. Reid, P. Renton, J.M. Roney, R. Sekulin, R. Tenchini, F. Teubert, M.A. Thomson, J. Timmermans, M.F. Turner-Watson, H. Wahlen, C.P. Ward, D.R. Ward, N.K. Watson, A. Weber. zN. de Groot, E. Etzion, B. Schumm, D. Su.
323 citations
Posted Content•
06 Apr 2002
TL;DR: In this article, a systematic error in the extraction of W$ from nuclear deep inelastic scattering of neutrinos and antineutrinos arises from higher-twist effects arising from nuclear shadowing.
Abstract: A systematic error in the extraction of $\sin^2 \theta_W$ from nuclear deep inelastic scattering of neutrinos and antineutrinos arises from higher-twist effects arising from nuclear shadowing. We explain that these effects cause a correction to the results of the recently reported significant deviation from the Standard Model that is potentially as large as the deviation claimed, and of a sign that cannot be determined without an extremely careful study of the data set used to model the input parton distribution functions.
307 citations
TL;DR: The complete set of electroweak corrections to the Drell-Yan-like production of W bosons is calculated and compared to an approximation provided by the leading term of an expansion about the W-resonance pole as discussed by the authors.
Abstract: The complete set of electroweak $O(\ensuremath{\alpha})$ corrections to the Drell-Yan-like production of W bosons is calculated and compared to an approximation provided by the leading term of an expansion about the W-resonance pole. All relevant formulas are listed explicitly, and particular attention is paid to issues of gauge invariance and the instability of the W bosons. A detailed discussion of numerical results underlines the phenomenological importance of the electroweak corrections to W-boson production at the Fermilab Tevatron and at the CERN Large Hadron Collider. While the pole expansion yields a good description of resonance observables, it is not sufficient for the high-energy tail of transverse-momentum distributions, relevant for new-physics searches.
270 citations
TL;DR: In this paper, the effect of the radiative corrections on the l+l- invariant mass distribution, the cross section in the Z boson resonance region, and on the forward-backward asymmetry, A_FB, at the Fermilab Tevatron and the CERN Large Hadron Collider were investigated.
Abstract: We calculate the complete electroweak O(alpha) corrections to pp, pbar p -> l+l- X (l=e, mu) in the Standard Model of electroweak interactions. They comprise weak and photonic virtual one-loop corrections as well as real photon radiation to the parton-level processes q bar q -> gamma,Z -> l+l-. We study in detail the effect of the radiative corrections on the l+l- invariant mass distribution, the cross section in the Z boson resonance region, and on the forward-backward asymmetry, A_FB, at the Fermilab Tevatron and the CERN Large Hadron Collider. The weak corrections are found to increase the Z boson cross section by about 1%, but have little effect on the forward-backward asymmetry in the Z peak region. Threshold effects of the W box diagrams lead to pronounced effects in A_FB at m(l+l-) approx 160 GeV which, however, will be difficult to observe experimentally. At high di-lepton invariant masses, the non-factorizable weak corrections are found to become large.
249 citations
TL;DR: In this article, a detailed analysis of the production of gravitational waves during an electroweak phase transition in different supersymmetric models where, contrary to the case of the Standard Model, the transition can be first order is presented.
TL;DR: In this paper, a detailed study of elastic WW scattering in the scenario that there are no new particles discovered prior to the commissioning of the CERN LHC is presented, and the effect of different assumptions about the underlying event is also studied.
Abstract: A detailed study is presented of elastic WW scattering in the scenario that there are no new particles discovered prior to the commissioning of the CERN LHC. We work within the framework of the electroweak chiral Lagrangian and two different unitarization protocols are investigated. Signals and backgrounds are simulated to the final-state-particle level. A new technique for identifying the hadronically decaying W is developed, which is more generally applicable to massive particles which decay to jets where the separation of the jets is small. The effect of different assumptions about the underlying event is also studied. We conclude that the channel WW-->jj+lν may contain scalar and/or vector resonances which could be measurable after 100 fb-1 of LHC data.
TL;DR: In this article, the authors investigated the possibility that the inclusion of additional bottom-like quarks could help resolve the discrepancy between the measurements of the leptonic and hadronic asymmetries at lepton colliders, which may indicate new physics contributions to the precision electroweak observables.
Abstract: The standard model (SM) with a light Higgs boson provides a very good description of the precision electroweak observable data coming from the CERN LEP, SLD and Fermilab Tevatron experiments. Most of the observables, with the notable exception of the forward-backward asymmetry of the bottom quark, point towards a Higgs boson mass far below its current experimental bound. The disagreement, within the SM, between the values for the weak mixing angle as obtained from the measurement of the leptonic and hadronic asymmetries at lepton colliders, may be taken to indicate new physics contributions to the precision electroweak observables. In this article we investigate the possibility that the inclusion of additional bottomlike quarks could help resolve this discrepancy. Two inequivalent assignments for these new quarks are analyzed. The resultant fits to the electroweak data show a significant improvement when compared to that obtained in the SM. While in one of the examples analyzed the exotic quarks are predicted to be light, with masses below 300 GeV, and the Higgs boson tends to be heavy, in the second one the Higgs boson is predicted to be light, with a mass below 250 GeV, while the quarks tend to be heavy, with masses of about 800 GeV. The collider signatures associated with the new exotic quarks, as well as the question of unification of couplings within these models and a possible cosmological implication of the new physical degrees of freedom at the weak scale are also discussed.
TL;DR: In this article, a comprehensive study of rare charm decays was performed, incorporating the first evaluation of the QCD corrections to the short distance contributions, as well as examining the long range effects.
Abstract: We perform a comprehensive study of a number of rare charm decays, incorporating the first evaluation of the QCD corrections to the short distance contributions, as well as examining the long range effects. For processes mediated by the c → ul + l − transitions, we show that sensitivity to short distance physics exists in kinematic regions away from the vector meson resonances that dominate the total rate. In particular, we find that D → πl + l − and D → ρl + l − are sensitive to non-universal soft-breaking effects in the Minimal Supersymmetric Standard Model with R-parity conservation. We separately study the sensitivity of these modes to R-parity violating effects and derive new bounds on R-parity violating couplings. We also obtain predictions for these decays within extensions of the Standard Model, including extensions of the Higgs, gauge and fermion sectors, as well as models of dynamical electroweak symmetry breaking.
TL;DR: In this paper, a new class of realistic models for electroweak symmetry breaking have been constructed, without supersymmetry, which have naturally light Higgs bosons and perturbative new physics at the TeV scale.
Abstract: Recently, a new class of realistic models for electroweak symmetry breaking have been constructed, without supersymmetry. These theories have naturally light Higgs bosons and perturbative new physics at the TeV scale. We describe these models in detail, and show that electroweak symmetry breaking can be triggered by a large top quark Yukawa coupling. A rich spectrum of particles is predicted, with a pair of light Higgs doublets accompanied by new light weak triplet and singlet scalars. The lightest of these new scalars is charged under a geometric discrete symmetry and is therefore stable, providing a new candidate for WIMP dark matter. At TeV energies, a plethora of new heavy scalars, gauge bosons and fermions are revealed, with distinctive quantum numbers and decay modes.
TL;DR: In this article, the authors discuss the implications of cosmological time shifts of the fine structure constant from the point of view of particle physics and show that the relative change of the nucleon mass is about 40 times larger than that of α.
Abstract: Starting from astrophysical indications that the fine structure constant might undergo a small cosmological time shift, we discuss the implications of such an effect from the point of view of particle physics. Grand unification implies small time shifts for the nucleon mass, the magnetic moment of the nucleon and the weak coupling constant as well. The relative change of the nucleon mass is about 40 times larger than the relative change of α. Laboratory measurements using very advanced methods in quantum optics might soon reveal small time shifts of the nucleon mass, the magnetic moment of the nucleon and the fine structure constant.
TL;DR: In this article, the two-brane Randall-Sundrum (RS) model with bulk gauge fields was considered and a 4D low-energy effective Lagrangian was proposed.
Abstract: We consider the two-brane Randall-Sundrum (RS) model with bulk gauge fields. We carefully match the bulk theory to a 4D low-energy effective Lagrangian. In addition to the four-fermion operators induced by KK exchange we find that large negative S and T parameters are induced in the effective theory. This is a tree-level effect and is a consequence of the shapes of the W and Z wave functions in the bulk. Such effects are generic in extra dimensional theories where the standard model (SM) gauge bosons have non-uniform wave functions along the extra dimension. The corrections to precision electroweak observables in the RS model are mostly dominated by S. We fit the parameters of the RS model to the experimental data and find somewhat stronger bounds than previously obtained; however, the standard model bound on the Higgs mass from precision measurements can only be slightly relaxed in this theory.
TL;DR: In this paper, it was shown that the electroweak Higgs particles can be identified with extra-dimensional components of the gauge fields, which after compactification on a certain topologically non-trivial background become tachyonic and condense.
Abstract: We suggest that the electroweak Higgs particles can be identified with extra-dimensional components of the gauge fields, which after compactification on a certain topologically non-trivial background become tachyonic and condense. If the tachyonic mass is a tree level effect, the natural scale of the gauge symmetry breaking is set by the inverse radius of the internal space, which, in case of the electroweak symmetry, must be around $\sim 1/$TeV. We discuss the possibility of a vanishing tree level mass for the Higgs. In such a scenario the tachyonic mass can be induced by quantum loops and can be naturally smaller than the compactification scale. We give an example in which this possibility can be realized. Starting from an Einstein--Yang--Mills theory coupled to fermions in 10-dimensions, we are able to reproduce the spectrum of the Standard Model like chiral fermions and Higgs type scalars in 4-dimensions upon compactifying on ${\mathbb{C}}P^1\times {\mathbb{C}}P^2$. The existence of a monopole solution on ${\mathbb{C}}P^1$ and a self dual U(1) instanton on ${\mathbb{C}}P^2$ are essential in obtaining chiral fermions as well as tachyonic or massless scalars in 4-dimensions. We give a simple rule which helps us to identify the presence of tachyons on the monopole background on $S^2$.
TL;DR: In this article, the dominant two and higher-loop contributions to the 205 Tl, neutron and muon electric dipole moments induced by Higgs bosons, third generation quarks and squarks, charginos and gluinos in the Minimal Supersymmetric Standard Model (MSSM) were studied.
TL;DR: In this article, a phenomenological application of the joint resummation formalism to electroweak annihilation processes at a measured boson momentum was presented, which simultaneously resums at next-to-leading logarithmic accuracy with large threshold and recoil corrections to partonic scattering.
Abstract: We present a phenomenological application of the joint resummation formalism to electroweak annihilation processes at a measured boson momentum ${Q}_{T}$ This formalism simultaneously resums at next-to-leading logarithmic accuracy large threshold and recoil corrections to partonic scattering We invert the impact parameter transform using a previously described analytic continuation procedure This leads to a well-defined, resummed perturbative cross section for all nonzero ${Q}_{T},$ which can be compared to resummation carried out directly in ${Q}_{T}$ space From the structure of the resummed expressions, we also determine the form of nonperturbative corrections to the cross section and implement these into our analysis We obtain a good description of the transverse momentum distribution of Z bosons produced at the Fermilab Tevatron collider
TL;DR: In this article, a complete study of the vacuum structure of top quark seesaw models of the electroweak symmetry breaking, including bottom quark mass generation, is presented, along with an improved broken phase formulation for including exact seesaw mixings.
Abstract: We present a complete study of the vacuum structure of top quark seesaw models of the electroweak symmetry breaking, including bottom quark mass generation. Such models emerge naturally from bosonic extra dimensions. We perform a systematic gap equation analysis and develop an improved broken phase formulation for including exact seesaw mixings. The composite Higgs boson spectrum is studied in the large-${N}_{c}$ fermion-bubble approximation and an improved renormalization group approach. The theoretically allowed parameter space is restrictive, leading to well-defined predictions. We further analyze the electroweak precision constraints. Generically, a heavy composite Higgs boson with a mass of $\ensuremath{\sim}1 \mathrm{TeV}$ is predicted, yet fully compatible with the precision data.
TL;DR: In this article, the authors discuss the phenomenology of a three-family supersymmetric standard-like model derived from the orientifold construction, in which the ordinary chiral states are localized at the intersection of branes at angles.
Abstract: We discuss the phenomenology of a three-family supersymmetric standardlike model derived from the orientifold construction, in which the ordinary chiral states are localized at the intersection of branes at angles In addition to the standard model group, there are two additional ${U(1)}^{\ensuremath{'}}$ symmetries, one of which has family nonuniversal and therefore flavor changing couplings, and a quasihidden non-Abelian sector which becomes strongly coupled above the electroweak scale The perturbative spectrum contains a fourth family of exotic $[\mathrm{SU}(2)$-singlet] quarks and leptons, in which, however, the left-chiral states have unphysical electric charges It is argued that these decouple from the low energy spectrum due to hidden sector charge confinement, and that anomaly matching requires the physical left-chiral states to be composites The model has multiple Higgs doublets and additional exotic states The moduli-dependent predictions for the gauge couplings are discussed The strong coupling agrees with experiment for reasonable moduli, but the electroweak couplings are too small
TL;DR: In this paper, it was shown that the existence of extra U(1) gauge symmetries beyond hypercharge can be found in D-brane string models with a low string scale MS 1 -10 TeV, and that some fraction of the experimentally measured Z 0 mass would be due to mixing with these closed string fields.
Abstract: Generic D-brane string models of particle physics predict the existence of extra U(1) gauge symmetries beyond hypercharge. These symmetries are not of the E6 class but rather include the gauging of Baryon and Lepton numbers as well as certain Peccei-Quinn-like symmetries. Some of the U(1)'s have triangle anomalies, but they are cancelled by a Green-Schwarz mechanism. The corresponding gauge bosons typically acquire a mass of order the string scale MS by combining with two-index antisymmetric fields coming from the closed string sector of the theory. We argue that in string models with a low string scale MS1--10 TeV, the presence of these generic U(1)'s may be amenable to experimental test. Present constraints from electroweak precision data already set important bounds on the mass of these extra gauge bosons. In particular, for large classes of models, ?-parameter constraints imply MS ? 1.5 TeV. In the present scheme some fraction of the experimentally measured Z0 mass would be due not to the Higgs mechanism, but rather to the mixing with these closed string fields. We give explicit formulae for recently constructed classes of intersecting D6- and D5-brane models yielding the Standard Model (SM) fermion spectrum.
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TL;DR: In this paper, the authors studied M theory compactifications on manifolds of $G_2$-holonomy with gauge and matter fields supported at singularities and showed that the combination of background $G$-flux and background fields at the singularities induces a potential for the moduli with an isolated minimum.
Abstract: We study M theory compactifications on manifolds of $G_2$-holonomy with gauge and matter fields supported at singularities. We show that, under certain topological conditions, the combination of background $G$-flux and background fields at the singularities induces a potential for the moduli with an isolated minimum. The theory in the minimum is supersymmetric and has a negative cosmological constant in the simplest case. In a more realistic scenario, we find that the fundamental scale is around 10 Tev and the heirarchy between the four dimensional Planck and electroweak scales may be explained by the value of a topological invariant. Hyperbolic three-manifolds enter the discussion in an interesting way.
TL;DR: In this paper, the two-loop electroweak hadronic contributions to the muon g−2 were analyzed by using the algebra Ward identities and the inclusion of the correct short-distance QCD behaviour of the relevant hadronic Green's function.
Abstract: We reanalyze the two-loop electroweak hadronic contributions to the muon g−2 that may be enhanced by large logarithms. The present evaluation is improved over those already existing in the literature by the implementation of the current algebra Ward identities and the inclusion of the correct short-distance QCD behaviour of the relevant hadronic Green's function.
TL;DR: In this paper, the pole masses of the charged and neutral Higgs bosons in the minimal supersymmetric standard model (MSSM) with explicit CP violation are derived, and compared with previous results obtained in the effective potential approach.
TL;DR: In this article, the electroweak Higgs doublets are identified as components of a vector multiplet in a higher-dimensional supersymmetric field theory, and a minimal model in 6D where the SU(2)⊗U(1) gauge group is extended to SU(3), and unified 6D models with the unified SU(5) gauge symmetry extended toSU(6).
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TL;DR: In this article, an economical theory of natural electroweak symmetry breaking was proposed, which stabilizes the electroweak scale with a naturally light Higgs and weakly coupled new physics at TeV energies.
Abstract: We present an economical theory of natural electroweak symmetry breaking, generalizing an approach based on deconstruction. This theory is the smallest extension of the Standard Model to date that stabilizes the electroweak scale with a naturally light Higgs and weakly coupled new physics at TeV energies. The Higgs is one of a set of pseudo Goldstone bosons in an $SU(5)/SO(5)$ nonlinear sigma model. The symmetry breaking scale $f$ is around a TeV, with the cutoff $\Lambda \lsim 4\pi f \sim $ 10 TeV. A single electroweak doublet, the ``little Higgs'', is automatically much lighter than the other pseudo Goldstone bosons. The quartic self-coupling for the little Higgs is generated by the gauge and Yukawa interactions with a natural size $O(g^2,\lambda_t^2)$, while the top Yukawa coupling generates a negative mass squared triggering electroweak symmetry breaking. Beneath the TeV scale the effective theory is simply the minimal Standard Model. The new particle content at TeV energies consists of one set of spin one bosons with the same quantum numbers as the electroweak gauge bosons, an electroweak singlet quark with charge 2/3, and an electroweak triplet scalar. One loop quadratically divergent corrections to the Higgs mass are cancelled by interactions with these additional particles.
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TL;DR: The NuTeV Collaboration has extracted the electroweak parameter sin(2)theta(W) from the measurement of the ratios of neutral current to charged current nu and (-)nu cross sections and presents a model independent analysis of the same data in terms of neutral-current quark couplings.
Abstract: In a recent comment, Miller and Thomas assert that differences in nuclear shadowing effects between neutrino neutral current (NC) and charged current (CC) interactions could explain the difference between NuTeV's measurement of the weak mixing angle and the prediction from other electroweak data We argue that the proposed effect could have only a small impact on sin2thetaW derived from the Paschos-Wolfenstein R- and that such an effect is strongly disfavored by the neutrino and anti-neutrino NC-to-CC cross-section ratios also measured by NuTeV
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TL;DR: In this article, two lectures on technicolor and extended technicolors were presented at l'Ecole de GIF at LAPP, Annecy-le-Vieux, France, in September 2001.
Abstract: These two lectures on technicolor and extended technicolor (ETC) were presented at l'Ecole de GIF at LAPP, Annecy-le-Vieux, France, in September 2001. In Lecture I, the motivation and structure of this theory of dynamical breaking of electroweak and flavor symmetries is summarized. The main phenomenological obstacles to this picture--flavor-changing neutral currents, precision electroweak measurements, and the large top-quark mass--are reviewed. Then, their proposed resolutions--walking technicolor and topcolor-assisted technicolor are discussed. In Lecture II, a scenario for CP violation is presented based on vacuum alignment for technifermions and quarks. It has the novel feature of CP--violating phases that are rational multiples of pi to better than one part in 10^{10} without fine-tuning of parameters. The scheme thereby avoids light axions and a massless up quark. The mixing of neutral mesons, the mechanism of top--quark mass generation, and the CP--violating parameters epsilon and sin(2 beta) strongly constrain the form of ETC--generated quark mass matrices.