arXiv subjects

A. R. White

Publications and source records attributed to A. R. White.

5 recordsLinked to original sources

arXiv1995

Higher-Order Corrections to BFKL Evolution from $t$-Channel Unitarity

Using reggeon diagrams as a partial implementation of $t$-channel unitarity, $O(g^4)$ 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 $O(g^2)$ BFKL kernel and the $O(g^4)$ corrections can then be derived.

hep-ph↗

arXiv1995

Scale Invariant $O(g^4)$ Lipatov Kernels at Non-Zero Momentum Transfer

We summarize recent work on the evaluation of the scale invariant next-to-leading order Lipatov kernel, constructed via transverse momentum diagrams. At zero momentum transfer the square of the leading-order kernel appears together with an additional component, now identified as a new partial-wave amplitude, having a separate, holomorphically factorizable, spectrum. We present a simplified expression for the full kernel at non-zero momentum transfer and give a complete analysis of its infrared properties. We also construct a non-forward extension of the new amplitude which is infra-red finite and satifies Ward identity constraints. We conjecture that this new kernel has the conformal invariance properties corresponding to the holomorphic factorization of the forward spectrum.

hep-ph↗

arXiv1995

The High Energy Behavior of the Forward Scattering Parameters---An Amplitude Analysis Update

Utilizing the most recent experimental data, we reanalyze high energy \pbar p and pp data, using the asymptotic amplitude analysis, under the assumption that we have reached `asymptopia'. This analysis gives strong evidence for a $\log \,(s/s_0)$ dependence at {\em current} energies and {\em not} $\log^2 (s/s_0)$, and also demonstrates that odderons are {\em not} necessary to explain the experimental data.

hep-ph↗

arXiv1994

The High Energy Behavior of the Forward Scattering Parameters σtotal $ρ$, and $B$

Utilizing the most recent experimental data, we reanalyze high energy \pbar p and pp data, using two distinct (and {\em dissimilar}) analysis techniques: (1) asymptotic amplitude analysis, under the assumption that we have reached `asymptopia', and (2) an eikonal model whose amplitudes are designed to mimic real QCD amplitudes. The former gives strong evidence for a $\log \,(s/s_0)$ dependence at {\em current} energies and {\em not} $\log^2 (s/s_0)$, and demonstrates that odderons are {\em not} necessary to explain the experimental data. The latter gives a unitary model for extrapolation into true `asymptopia' from current energies, allowing us to predict the values of the total cross section at future supercolliders. Using our QCD-model, we obtain $\stot(16\,\, {\rm TeV})=109\pm4$\,mb and $\stot(40\,\, {\rm TeV})=124\pm4$\,mb.

hep-ph↗

arXiv1994

Scale-Invariant Lipatov Kernels from t-Channel Unitarity

The Lipatov equation can regarded as a reggeon Bethe-Salpeter equation in which higher-order reggeon interactions give higher-order kernels. Infra-red singular contributions in a general kernel are produced by t-channel nonsense states and the allowed kinematic forms are determined by unitarity. Ward identity and infra-red finiteness gauge invariance constraints then determine the corresponding scale-invariant part of a general higher-order kernel.

hep-ph↗