Massive event-shape distributions at N<sup>2</sup>LL
- Author(s)
- Alejandro Bris, Vicent Mateu, Moritz Preisser
- Abstract
In a recent paper we have shown how to optimally compute the differential and cumulative cross sections for massive event-shapes at O(ffs) in full QCD. In the present article we complete our study by obtaining resummed expressions for non-recoil-sensitive observables to N2LL + O(ffs) precision. Our results can be used for thrust, heavy jet mass and C-parameter distributions in any massive scheme, and are easily generalized to angularities and other event shapes. We show that the so-called E- and P-schemes coincide in the collinear limit, and compute the missing pieces to achieve this level of accuracy: the P-scheme massive jet function in Soft-Collinear Effective Theory (SCET) and boosted Heavy Quark Effective Theory (bHQET). The resummed expression is subsequently matched into fixed-order QCD to extend its validity towards the tail and fartail of the distribution. The computation of the jet function cannot be cast as the discontinuity of a forward-scattering matrix element, and involves phase space integrals in d = 4 2" dimensions. We show how to analytically solve the renormalization group equation for the P-scheme SCET jet function, which is significantly more complicated than its 2-jettiness counterpart, and derive rapidly-convergent expansions in various kinematic regimes. Finally, we perform a numerical study to pin down when mass effects become more relevant.
- Organisation(s)
- Particle Physics
- External organisation(s)
- Universidad Autónoma de Madrid, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Salamanca
- Journal
- Journal of High Energy Physics
- No. of pages
- 58
- ISSN
- 1029-8479
- DOI
- https://doi.org/10.1007/JHEP09(2020)132
- Publication date
- 09-2020
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 103012 High energy physics
- Keywords
- Portal url
- https://ucris.univie.ac.at/portal/en/publications/massive-eventshape-distributions-at-n2ll(0f69ac65-dcfd-4000-baf2-7b66705a2b31).html