Advanced search    

Search: authors:"Jonathan R. Gaunt"

10 papers found.
Use AND, OR, NOT, +word, -word, "long phrase", (parentheses) to fine-tune your search.

Double hard scattering without double counting

Double parton scattering in proton-proton collisions includes kinematic regions in which two partons inside a proton originate from the perturbative splitting of a single parton. This leads to a double counting problem between single and double hard scattering. We present a solution to this problem, which allows for the definition of double parton distributions as operator matrix ...

Two-loop beam and soft functions for rapidity-dependent jet vetoes

Jet vetoes play an important role in many analyses at the LHC. Traditionally, jet vetoes have been imposed using a restriction on the transverse momentum p Tj of jets. Alternatively, one can also consider jet observables for which p Tj is weighted by a smooth function of the jet rapidity y j that vanishes as |y j | → ∞. Such observables are useful as they provide a natural way to ...

Cancellation of Glauber Gluon Exchange in the Double Drell–Yan Process

For any factorisation proof, a crucial step is a demonstration of the cancellation of so-called Glauber gluons. We summarise a recent paper in which we demonstrated this cancellation for double Drell–Yan production (the double parton scattering process in which a pair of electroweak gauge bosons is produced), both for the integrated cross section and for the cross section ...

Glauber gluons and multiple parton interactions

Jonathan R. Gaunt Theory Group Deutsches Elektronen-Synchrotron (DESY) D- Hamburg Germany We show that for hadronic transverse energy ET in hadron-hadron collisions, the classic Collins-Soper

The fully-differential quark beam function at NNLO

We present the first calculation of a fully-unintegrated parton distribution (beam function) at next-to-next-to-leading order (NNLO). We obtain the fully-differential beam function for quark-initiated processes by matching it onto standard parton distribution functions (PDFs) at two loops. The fully-differential beam function is a universal ingredient in resummed predictions of ...

Cancellation of Glauber gluon exchange in the double Drell-Yan process

An essential part of any factorisation proof is the demonstration that the exchange of Glauber gluons cancels for the considered observable. We show this cancellation at all orders for double Drell-Yan production (the double parton scattering process in which a pair of electroweak gauge bosons is produced) both for the integrated cross section and for the cross section differential ...

N-jettiness subtractions for NNLO QCD calculations

We present a subtraction method utilizing the N -jettiness observable, T N , to perform QCD calculations for arbitrary processes at next-to-next-to-leading order (NNLO). Our method employs soft-collinear effective theory (SCET) to determine the IR singular contributions of N -jet cross sections for T N → 0, and uses these to construct suitable T N -subtractions. The construction is ...

Single perturbative splitting diagrams in double parton scattering

Jonathan R. Gaunt 0 0 Cavendish Laboratory, University of Cambridge , J.J. Thomson Avenue, Cambridge CB3 0HE, U.K. Deutsches Elektronen-Synchroton DESY, 22603 Hamburg, Germany Open Access 1

The gluon beam function at two loops

Jonathan R. Gaunt Maximilian Stahlhofen Frank J. Tackmann Theory Group Deutsches Elektronen-Synchrotron (DESY) Notkestrae D- Hamburg Germany E-mail: The virtuality-dependent beam function is a

The quark beam function at two loops

Jonathan R. Gaunt Maximilian Stahlhofen Frank J. Tackmann In differential measurements at a hadron collider, collinear initial-state radiation is described by process-independent beam functions