Fully exclusive heavy quark-antiquark pair production from a colourless initial state at NNLO in QCD
- PDF / 875,854 Bytes
- 40 Pages / 595.276 x 841.89 pts (A4) Page_size
- 21 Downloads / 185 Views
Springer
Received: August 7, Revised: September 18, Accepted: October 13, Published: November 25,
2020 2020 2020 2020
Gábor Somogyia and Francesco Tramontanob a
MTA-DE Particle Physics Research Group, University of Debrecen, PO Box 105, 4010 Debrecen, Hungary b Università di Napoli and INFN, Sezione di Napoli, Complesso Universitario di Monte Sant’Angelo, Via Cintia, 80126 Napoli, Italy
E-mail: [email protected], [email protected] Abstract: We present a local subtraction scheme for computing next-to-next-to-leading order QCD corrections to the production of a massive quark-antiquark pair from a colourless initial state. The subtraction terms are built following the CoLoRFulNNLO method and refined in such a way that their integration gives rise to compact, fully analytic expressions. All ingredients necessary for a numerical implementation of our subtraction scheme are provided in detail. As an example, we calculate the fully differential decay rate of the Standard Model Higgs boson to massive bottom quarks at next-to-next-to-leading order accuracy in perturbative QCD. Keywords: Perturbative QCD, Higgs Physics ArXiv ePrint: 2007.15015
c The Authors. Open Access, Article funded by SCOAP3 .
https://doi.org/10.1007/JHEP11(2020)142
JHEP11(2020)142
Fully exclusive heavy quark-antiquark pair production from a colourless initial state at NNLO in QCD
Contents 1
2 Heavy quark-antiquark pair production from colourless initial states
2
3 Subtractions at NLO 3.1 Regularized real contribution 3.2 Regularized virtual contribution
4 5 6
4 Subtractions at NNLO 4.1 Regularized double real contribution 4.2 Regularized real-virtual contribution 4.3 Regularized double virtual contribution
7 8 19 25
5 Example: Higgs boson decay to massive bottom quarks
29
6 Conclusions
34
1
Introduction
Actual and planned CERN LHC operation opens the possibility to perform a large number of accurate measurements in high energy physics. It is clear that for many of them the overall experimental uncertainty will be much smaller than the theory uncertainty estimated based on next-to-leading order QCD corrections. Then, including higher order corrections turns out to be mandatory for a meaningful comparison among theory predictions and experimental data. Thus, next-to-next-to-leading order (NNLO) computation has received considerable attention and several approaches for performing these calculations have been proposed. These include the qT [1] and N -jettiness [2, 3] slicing methods, as well as subtraction schemes, like antenna [4–12], CoLoRFulNNLO [13–22], residue-improved [23–26], nested soft-collinear [27–31] and projection-to-Born [32] with yet other approaches under development [33–35]. From the mathematical point of view, computations at NNLO are more elaborate than ones at NLO and for this reason the level of automation is still much less advanced. On the one hand, difficulties lie in the computation of the double virtual amplitudes for processes with many particles in the final state and with masses.
Data Loading...
