Charged particles in ℤ2 gauge theories

In the free charge phase of the ₂ gauge-Higgs model on a lattice charged particles are shown to exist.Supported by DAADHeisenberg fellow     

O(5)×U(1) electroweak gauge theory and the neutrino oscillations in matter

A study is made of the groupO(5)×U(1). The group is economical in the number of gauge bosons, which we associate with each of its generators, and is anomaly-free. The left-handed leptonsL _L ^T (v _e ,e,,v ) _L are assigned to the four-dimensional spinorial representations ofO(5). The right-handed particles are taken to be the singlets of the group. The theory has three sets of gauge bosons: (1) analogues of the GWS model, (2) additional charged gauge bosons, and (3) a set of three additional neutral gauge bosons as compared to the GWS model. We introduce neutrino mixing by mixing the additional charged gauge bosons. We develope a theory of neutrino oscillations in matter in such a way that in the absence of matter the scattering length reduces to the usual scattering length in vacuum. Even if the neutrino masses are equal or the neutrinos are massless, we still have neutrino oscillations in matter, a result already noted by Wolfenstein.     

Classical hamiltonian reduction on D(2|1;α) Chern–Simons gauge theory and large N=4 superconformal symmetry

3d Chern–Simons gauge theory has a strong connection with 2d CFT and link invariants in knot theory. We impose some constraints on the D(2|1;α) CS theory in the similar context of the hamiltonian reduction of 2d superconformal algebras. There Hilbert states in D(2|1;α) CS theory are partly identified with characters of the large N=4 SCFT by their transformation properties.     

On the infrared scaling solution of SU(N) Yang–Mills theories in the maximally Abelian gauge

An improved method for extracting infrared exponents from functional equations is presented. The generalizations introduced allow for an analysis of quite complicated systems such as Yang–Mills theory in the maximally Abelian gauge. Assuming the absence of cancellations in the appropriately renormalized integrals the only consistent scaling solution yields an infrared enhanced diagonal gluon propagator in support of the Abelian dominance hypothesis. This is explicitly shown for SU(2) and subsequently verified for SU(N), where additional interactions exist. We also derive the most infrared divergent scaling solution possible for vertex functions in terms of the propagators’ infrared exponents. We provide general conditions for the existence of a scaling solution for a given system and comment on the cases of linear covariant gauges and ghost–anti-ghost symmetric gauges.     

Ψ and Υ Production in p-p Collisions at E = 5, 14 TeV; and Comparison with Experiment at E = 7 TeV

This brief report is an extension of our recent studies of Ψ and Υ production cross sections in proton-proton collisions with E \(=\sqrt {s}=13\) TeV to E = 5 and E =14 TeV, using the mixed heavy quark hybrid theory in which the Ψ(2S) and Υ(3S) are 50 % hybrid states. Also, comparison with recent experiments at E = 7 TeV are used to test the mixed heavy hybrid theory.     

U(N) SP(N) O(3)的分支律

利用群的直乘分解公式,考虑U(N)群的[2a1b]表示按群链U(N)SP(N)O(3)的约化规则,给出了相应的比较简单的分支律递推公式.该公式在用计算机计算分支律时,不受秩和表示维数的限制.为求解这类问题的分支律提供了一种比较简单的算法.在简化同位旋1/2的单j费米子体系的母分系数计算中具有十分重要的意义.用同样的方法也可以求出群链U(N)O(N)O(3)的分支律.     

Excited strange mesons and their decays in a chiral U(3)×U(3) Lagrangian

We bosonize the Nambu-Jona-Lasinio quark model with separable nonlocal interactions in order to derive a chiral U(3)×U(3) Lagrangian, containing, besides the usual meson fields, their first radial excitations. The spontaneous breaking of chiral symmetry is governed by the Nambu-Jona-Lasinio gap equation. The first radial excitations of the kaon, K*, and ? are described with the help of two form factors. The decays K*′ → ρK, K*′ → K*π, K*′ → Kπ, ?′ → K*K, ?′ → $\bar KK$ K, K′ → Kρ, K′ → K*π, and K′ → K2π are considered, and a qualitative agreement of our results with the experimental data is found.     

Adler–Bardeen theorem and manifest anomaly cancellation to all orders in gauge theories

We reconsider the Adler–Bardeen theorem for the cancellation of gauge anomalies to all orders, when they vanish at one loop. Using the Batalin–Vilkovisky formalism and combining the dimensional-regularization technique with the higher-derivative gauge invariant regularization, we prove the theorem in the most general perturbatively unitary renormalizable gauge theories coupled to matter in four dimensions, and we identify the subtraction scheme where anomaly cancellation to all orders is manifest, namely no subtractions of finite local counterterms are required from two loops onwards. Our approach is based on an order-by-order analysis of renormalization, and, differently from most derivations existing in the literature, does not make use of arguments based on the properties of the renormalization group. As a consequence, the proof we give also applies to conformal field theories and finite theories.     

Dynamical symmetry breaking in an SU(2)⊗U(1) model with two right singlets and gauge boson masses

A four-fermion interaction which includes right singlets of both up and down fermions is included in the initial locally SU(2)S(1)-invariant model. In the suitable approximation, the propagators are constructed and the mass spectrum is found of fermi and gauge vector fields as well as of the collective scalar fields due to the dynamical symmetry breakdown.Translated from Izvestiya Uchebnykh Zavedenii, Fizika, No. 4, pp. 98–104, April, 1990.     

Polarization observables in (γ,NN) reactions

The formalism of ( γ, NN) reactions is given where the incident photon is polarized and the outgoing-nucleon polarization is detected. Sixteen structure functions and fifteen polarization observables are found in the general case, while only eight structure functions and seven polarization observables survive in coplanar kinematics. Numerical examples are presented for the ¹⁶O(γ, np) and ¹⁶O(γ, pp) reactions. The transitions to the ground state of ¹⁴C and ¹⁴N are calculated in a model where realistic short-range and tensor correlations are taken into account for the np pair, while short-range and long-range correlations are included in a consistent way for pp pairs. The effects of the one-body and two-body components of the nuclear current and the role of correlations in cross-sections and polarizations are studied and discussed. Received: 7 June 2001 / Accepted: 26 September 2001     

Gauge boson masses and lepton mixing inO(4)⊗U(1) gauge model

The Cabibbo angle is introduced as a mixing angle of the gauge bosonsW ^± andX ^± in anO(4)?U(1) gauge model. Masses of gauge bosons are calculated to beM _W=82 (input), \(M_z = \sqrt 2 M_W s\gamma = 130\) (γ is mixing angle, sin² γ=0.21),M _x=666, andM _Y=660, in units GeV. TheW _μ ^± andZ _μ ⁰ couple to the familiar charged and neutral currents, respectively. The effective neutrino oscillation angle is found to be the Cabibbo angle.     

Tests for heavier gauge bosons in theSP(6) L ⊗U(1) Y model

Small deviations from the standard model may exist in the hadronic and leptonic cross sections at KEK. We explore the possibility that these may be accounted for by the extra gauge bosonsZ andW in theSP(6) _L U(1) _Y model, with its parameters constrained by the LEP data.     

The phase structure of SU(2) × U(1)Y lattice gauge theory

Using analytic and Monte Carlo techniques, we determine the phase structure and nature of spontaneous symmetry breaking of the SU(2) × U(1)_Y electroweak gauge theory with fixed-length Higgs fields on a lattice. We find that it has two completely separated phases: (a) a disordered, symmetric phase and (b) a phase in which SU(2) × U(1)_Y is spontaneously broken to U(1)_em, which is realized in its deconfined Coulomb phase with massless photons. Exact analytic results and approximate series expansions are given for various special cases of the theory.