Effective Predictions of Event Shapes: Factorized, Resummed, and Gapped Angularity Distributions

Physics – High Energy Physics – High Energy Physics - Phenomenology

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

52 pages, 13 figures, 1 table, uses JHEP3.cls. v2: comparison between SCET and QCD clarified, other minor corrections, v3: jou

Scientific paper

10.1088/1126-6708/2009/05/122

Using soft-collinear effective theory (SCET), which provides a unified framework for factorization, resummation of logarithms, and incorporation of universal nonperturbative functions in hard-scattering QCD cross-sections, we present a new prediction of angularity distributions in e+e- annihilation. Angularities tau_a are an infinite class of event shapes which vary in their sensitivity to the substructure of jets in the final state, controlled by a continuous parameter a<2. We calculate angularity distributions for all a<1 to first order in the strong coupling alpha_s and resum large logarithms in these distributions to next-to-leading logarithmic (NLL) accuracy. Our expressions for the next-to-leading order (NLO) O(alpha_s) partonic jet and soft functions in the factorization theorem for angularity distributions are given for the first time. We employ a model for the nonperturbative soft function with a gap parameter which cancels the renormalon ambiguity in the partonic soft function. We explore the relation between the SCET approach to resummation and past approaches in QCD, and discuss the advantages of the effective theory approach. In addition, we draw from the NLO calculations of the jet and soft functions an intuitive lesson about how factorization breaks down in the effective theory as a->1.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Effective Predictions of Event Shapes: Factorized, Resummed, and Gapped Angularity Distributions does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Effective Predictions of Event Shapes: Factorized, Resummed, and Gapped Angularity Distributions, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Effective Predictions of Event Shapes: Factorized, Resummed, and Gapped Angularity Distributions will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-360824

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.