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Reggeon Field Theory and the phases of QCD

Description: We propose a Reggeon Field Theory phase diagram involving Sub-critical and Super-critical Pomeron behavior and the Expanding Disc. We describe the derivation of Reggeon Field Theory from QCD using infra-red analysis of the reggeon diagrams of the spontaneously broken theory. Matching the Reggeon Field Theory phase-diagram to that of lattice QCD with many fermions has significant implications for the chiral properties of continuum QCD when the number of flavors is less than the maximum allowed by asymptotic freedom. 19 refs., 7 figs.
Date: July 21, 1987
Creator: White, A.R.
Partner: UNT Libraries Government Documents Department

Diffractive dissociation and new quarks

Description: We argue that the chiral limit of QCD can be identified with the strong (diffractive dissociation) coupling limit of reggeon field theory. Critical Pomeron scaling at high energy must then be directly related to an infra-red fixed-point of massless QCD and so requires a large number of flavors. This gives a direct argument that the emergence of diffraction-peak scaling, KNO scaling etc. at anti p-p colliders are evidence of a substantial quark structure still to be discovered.
Date: April 1, 1983
Creator: White, A.R.
Partner: UNT Libraries Government Documents Department

Diffraction theory in QCD and beyond

Description: A study of the Pomeron in QCD is briefly outlined. Implications for the production of W/sup +/W/sup -/ and Z/sup 0/Z/sup 0/ pairs are described and the possibility that the electroweak scale is a major strong-interaction threshold discussed. The application of Pomeron phase-transition theory to SU(5) dynamical symmetry breaking is suggested and the related ''strong-interaction'' properties of the photon briefly mentioned.
Date: December 11, 1987
Creator: White, A.R.
Partner: UNT Libraries Government Documents Department

QCD diffraction: a critical phenomenon reflecting both confinement and chiral-symmetry breaking

Description: Arguments are presented for studying soft diffractive physics at anti p-p colliders in terms of Critical Pomeron Reggeon Field Theory. It is emphasized that both confinement and chiral-symmetry breaking play a vital role in the occurrence of the Critical Pomeron in QCD. SU(3) is the unique strong-interaction gauge group giving the Critical Pomeron and the maximum number of quarks allowed by asymptotic freedom is required for criticality.
Date: July 1, 1982
Creator: White, A.R.
Partner: UNT Libraries Government Documents Department

Chiral symmetry breaking in gauge theories from Reggeon diagram analysis

Description: It is argued that reggeon diagrams can be used to study dynamical properties of gauge theories containing a large number of massless fermions. SU(2) gauge theory is studied in detail and it is argued that there is a high energy solution which is analogous to the solution of the massless Schwinger model. A generalized winding-number condensate produces the massless pseudoscalar spectrum associated with chiral symmetry breaking and a trivial'' S-Matrix.
Date: December 16, 1991
Creator: White, A.R.
Partner: UNT Libraries Government Documents Department

The supercritical pomeron in QCD.

Description: Deep-inelastic diffractive scaling violations have provided fundamental insight into the QCD pomeron, suggesting a single gluon inner structure rather than that of a perturbative two-gluon bound state. This talk outlines a derivation of a high-energy, transverse momentum cut-off, confining solution of QCD. The pomeron, in first approximation, is a single reggeized gluon plus a ''wee parton'' component that compensates for the color and particle properties of the gluon. This solution corresponds to a super-critical phase of Reggeon Field Theory.
Date: June 29, 1998
Creator: White, A. R.
Partner: UNT Libraries Government Documents Department

The anomaly and reggeon field theory in QCD

Description: The appearance of the U(1) anomaly in the interactions of reggeized gluons is described. Also discussed is the crucial role the anomaly can play in providing the non-perturbative properties necessary for a transition from gluon and quark reggeon diagrams to hadron reggeons and a reggeon field theory description of the pomeron.
Date: September 14, 2000
Creator: White, A. R.
Partner: UNT Libraries Government Documents Department

The triangle anomaly in the tripple-regge limit

Description: The U(l) triangle anomaly is present, as an infra-red divergence, in the six-reggeon triple-regge interaction vertex obtained from a maximally non-planar Feynman diagram in the full triple-regge limit of three-to-three quark scattering.
Date: November 22, 1999
Creator: White, A. R.
Partner: UNT Libraries Government Documents Department

Solving QCD via multi-Regge theory.

Description: To solve QCD at high-energy the authors must simultaneously find the hadronic states and the exchanged pomeron (IP) giving UNITARY scattering amplitudes. Experimentally, the IP {approximately} a Regge pole at small Q{sup 2} and a single gluon at larger Q{sup 2}. (F{sub 2}{sup D}-H1, dijets-ZEUS). In the solution which the author describes, these non-perturbative properties of the IP are directly related to the non-perturbative confinement and chiral symmetry breaking properties of hadrons.
Date: November 4, 1998
Creator: White, A. R.
Partner: UNT Libraries Government Documents Department

Solving QCD using multi-regge theory.

Description: This talk outlines the derivation of a high-energy, transverse momentum cut-off, solution of QCD in which the Regge pole and ''single gluon'' properties of the pomeron are directly related to the confinement and chiral symmetry breaking properties of the hadron spectrum. In first approximation, the pomeron is a single reggeized gluon plus a ''wee parton'' component that compensates for the color and particle properties of the gluon. This solution corresponds to a supercritical phase of Reggeon Field Theory.
Date: July 13, 1998
Creator: White, A. R.
Partner: UNT Libraries Government Documents Department

Solving QCD via multi-Regge theory.

Description: A high-energy, transverse momentum cut-off, solution of QCD is outlined. Regge pole and single gluon properties of the pomeron are directly related to the confinement and chiral symmetry breaking properties of the hadron spectrum. This solution, which corresponds to a supercritical phase of Reggeon Field Theory, may only be applicable to QCD with a very special quark content.
Date: November 4, 1998
Creator: White, A. R.
Partner: UNT Libraries Government Documents Department

t-Channel unitarity construction of small-x kernels

Description: In the leading-log approximation, the small-x behavior of parton distributions in QCD is derived from the BFKL evolution equation. The authors describe the ion as a reggeon Bethe-Salpeter equation and discuss the use of reggeon diagrams to obtain 2-2 and 2-4 reggeon interactions at O(g{sup 4}). They then outline the dispersion theory basis of multiparticle j-plane analysis and describe how a gauge theory can be studied by combining Ward identity constraints with the group structure of reggeon interactions. Gluon reggeization, the O(g{sup 2}) BFKL kernel and O(g{sup 4}) corrections to it, are derived within this formalism. They give an explicit expression for the O(g{sup 4}) forward ``parton`` kernel in terms of logarithms and evaluate the eigenvalues. A separately infra-red finite component with a holomorphically factorizable spectrum is shown to be present and conjectured to be a new leading-order partial-wave amplitude. A comparison is made with Kirschner`s discussion of O(g{sup 4}) contributions from the multi-Regge effective action.
Date: 1994-12~
Creator: Coriano, C. & White, A. R.
Partner: UNT Libraries Government Documents Department

Gauge theory high-energy behavior from J-plane unitarity

Description: In a non-abelian gauge theory the t-channel multiparticle unitarity equations continued in the complex j-plane can be systematically expanded around j = 1. The combination of Ward identity constraints with unitarity is sufficient to produce directly many results obtained by Regge limit leading-log and next-to-leading log momentum space calculations. The O(g{sup 2}) BFKL kernel is completely determined. O(g{sup 4}) contributions to the kernel are also determined, including the leading contribution of a new partial-wave amplitude--previously identified as a separate forward component with a holomorphically factorizable spectrum. For this amplitude the only scale ambiguity is the overall normalization and it is anticipated to be a new conformally invariant kernel. The results suggest that all conformally invariant reggeon interactions are determined by t-channel unitarity.
Date: December 31, 1995
Creator: Coriano, C. & White, A.R.
Partner: UNT Libraries Government Documents Department

Excess cross-sections at the electroweak scale in the sextet quark {open_quotes}standard model{close_quotes}

Description: If dynamical electroweak symmetry breaking is due to a flavor doublet of color sextet quarks, enhanced electroweak scale QCD instanton interactions may produce a large top mass, raise the {eta}{sub 6} axion mass, and also explain the excesses in the DIS cross-section at HERA and jet cross-sections at the Tevatron.
Date: June 30, 1997
Creator: White, A.R.
Partner: UNT Libraries Government Documents Department

The Pomeron beyond BFKL

Description: Conformally invariant reggeon interactions derived from t-channel unitarity are discussed and progress towards understanding the {open_quotes}physical Pomeron{close_quotes}, via massless quark reggeon interactions, is briefly out-lined.
Date: May 12, 1997
Creator: White, A. R.
Partner: UNT Libraries Government Documents Department

The hard gluon component of the QCD Pomeron

Description: The authors argue that deep-inelastic diffractive scaling provides fundamental insight into the QCD Pomeron. The logarithmic scaling violations seen experimentally are in conflict with the scale-invariance of the BFKL Pomeron and with phenomenological two-gluon models. Instead the Pomeron appears as a single gluon at short-distances, indicating the appearance of a Super-Critical phase of Reggeon Field Theory. That the color compensation takes place at a longer distance is consistent with the Pomeron carrying odd color charge parity.
Date: October 20, 1996
Creator: White, A.R.
Partner: UNT Libraries Government Documents Department

Deep-inelastic diffraction and the pomeron as a single gluon

Description: Deep-inelastic diffractive scaling provides fundamental insight into the QCD pomeron. It is argued that single gluon domination of the structure function, together with the well-known Regge pole property, determines that the pomeron carries color-change parity C{sub c} = {minus}1 and, at short distances, is in a super-critical phase of Reggeon Field Theory. The main purpose of the talk is to describe the relationship of the super-critical pomeron to QCD.
Date: September 3, 1997
Creator: White, A.R.
Partner: UNT Libraries Government Documents Department

The VIIth Blois workshop: Theory summary and factorization issues

Description: Theory presentations at this workshop have covered a wide range of topics. In addition to the traditional topics of elastic and diffractive scattering, the workshop has had a variety of interesting talks coming under the broad umbrella of ``Recent Advances in Hadron Physics.`` These have included review talks on lattice gauge theory, techniques for high-order perturbative QCD calculations, strong interaction effective field theories, the current status of QED and the construction of theories beyond the Standard Model. While the author briefly describes some topics covered, a ``review of reviews`` is in no way a substitute for the original reviews which also appear, of course, in this same volume. Among the more traditional topics covered are: BFKL physics -- higher-order corrections and jet cross-sections; unitarity and eikonal screening -- mainly in deep-inelastic diffraction but also in soft diffraction; elastic scattering phenomenology -- including real parts, the pomeron intercept and small-t oscillations. Also discussed is the role of factorization, i.e. both Regge pole factorization and perturbative QCD factorization theorems in the definition of a pomeron structure function and in the formulation of a parton model description of diffractive hard physics. The author focuses on one gluon versus two gluons as illustrating the issues involved.
Date: September 17, 1997
Creator: White, A.R.
Partner: UNT Libraries Government Documents Department

Higher-order corrections to BFKL evolution from t-channel unitarity

Description: Using reggeon diagrams as a partial implementation of t-channel unitarity, O(g{sup 4}) corrections to the BFKL evolution equation have been obtained. We describe the spectrum and holomorphic factorization properties of the resulting scale-invariant kernel. For a gauge theory, t-channel unitarity can be studied directly in the complex j-plane by implementing Ward identity constraints together with the group structure of reggeon interactions. We discuss how both the O(g{sup 2}) BFKL kernel and the O(g{sup 4}) corrections can then be derived.
Date: 1994-12~
Creator: Coriano, C. & White, A. R.
Partner: UNT Libraries Government Documents Department

t-Channel unitarity construction of small-x kernels

Description: The authors present the BFKL equation as a reggeon Bethe-Salpeter equation and discuss the use of reggeon diagrams to obtain 2-2 and 2-4 reggeon interactions at O(g{sup 4}). They then outline the dispersion theory basis of multiparticle j-plane analysis and describe how a gauge theory can be studied by combining Ward identity constraints with the group structure of reggeon interactions. The derivation of gluon reggeization, the O(g{sup 2}) BFKL kernel, and O(g{sup 4}) corrections, is described within this formalism. They give an explicit expression for the O(g{sup 4}) forward ``parton`` kernel in terms of logarithms and evaluate the eigenvalues. A separately infra-red finite component with a holomorphically factorizable spectrum is shown to be present and conjectured to be a new leading-order partial-wave amplitude. A comparison is made with Kirschner`s discussion of O(g{sup 4}) contributions from the multi-Regge effective action.
Date: December 1995
Creator: Coriano, C. & White, A. R.
Partner: UNT Libraries Government Documents Department

Conformally symmetric contributions to BFKL evolution at next to leading order

Description: Unitarity corrections to the BFKL evolution at next to leading order determine a new component of the evolution kernel which is shown to possess conformal invariance properties. Expressions for the complete spectrum of the new component and the correction to the intercept of the pomeron trajectory are presented.
Date: July 1, 1995
Creator: Coriano, C. & White, A.R.
Partner: UNT Libraries Government Documents Department

Confinement and the Pomeron

Description: The importance of confinement for obtaining a unitary high-energy limit for QCD is discussed. Minijets'' are argued to build up non-unitary behavior{endash}when k{sub T} {gt} {Lambda} is imposed. For minijets to mix with low k{sub T} Pomeron Field Theory describing confinement, and give consistent asymptotic behavior, new quarks'' must enter the theory above the minijet transverse momentum scale. The Critical Pomeron is the resulting high-energy limit. 22 refs.
Date: September 25, 1989
Creator: White, A.R.
Partner: UNT Libraries Government Documents Department

NLO conformal symmetry in the Regge limit of QCD

Description: The authors show that a scale invariant approximation to the next-to-leading order BFKL kernel, constructed via transverse momentum diagrams, has a simple conformally invariant representation in impact parameter space. That a conformally invariant representation exists is shown first by relating the kernel directly to Feynman diagrams contributing to two photon diffractive dissociation.
Date: September 18, 1996
Creator: Coriano, C.; White, A. R. & Wuesthoff, M.
Partner: UNT Libraries Government Documents Department

The high energy behavior of the forward scattering parameters - an amplitude analysis update

Description: Utilizing the most recent experimental data, we reanalyze high energy pp and pp data, using the asymptotic amplitude analysis, under the assumption that we have reached {open_quotes}asymptopia{close_quotes}. This analysis gives strong evidence for a log (s/s{sub 0}) dependence at current energies and not log{sup 2} (s/s{sub 0}), and also demonstrates that odderons are not necessary to explain the experimental data.
Date: December 1995
Creator: Block, M. M.; Margolis, B. & White, A. R.
Partner: UNT Libraries Government Documents Department