Soft gluon evolution and non-global logarithms

Autor(en)

Rene Angeles Martinez, Matthew De Angelis, Jeffrey R. Forshaw, Simon Plätzer, Michael H. Seymour

Abstrakt

We consider soft-gluon evolution at the amplitude level. Our evolution algorithm applies to generic hard-scattering processes involving any number of coloured partons and we present a reformulation of the algorithm in such a way as to make the cancellation of infrared divergences explicit. We also emphasise the special role played by a Lorentz-invariant evolution variable, which coincides with the transverse momentum of the latest emission in a suitably defined dipole zero-momentum frame. Handling large colour matrices presents the most significant challenge to numerical implementations and we present a means to expand systematically about the leading colour approximation. Specifically, we present a systematic procedure to calculate the resulting colour traces, which is based on the colour flow basis. Identifying the leading contribution leads us to re-derive the Banfi-Marchesini-Smye equation. However, our formalism is more general and can systematically perform resummation of contributions enhanced by the t’Hooft coupling α

_sN ∼ 1, along with successive perturbations that are parametrically suppressed by powers of 1/N. We also discuss how our approach relates to earlier work.

Organisation(en)

Teilchenphysik

Externe Organisation(en)

Polish Academy of Sciences (PAS), University of Manchester, European Organization for Nuclear Research (CERN)

Journal

Journal of High Energy Physics

Band

2018

Anzahl der Seiten

35

ISSN

1029-8479

Publikationsdatum

05-2018

Peer-reviewed

Ja

ÖFOS 2012

103012 Hochenergiephysik

Schlagwörter

ASJC Scopus Sachgebiete

Nuclear and High Energy Physics

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/e4570bf1-6177-4d4a-8e13-7685c3b9ca7f