The NNLO quark beam function for jet-veto resummation

We compute the complete set of two-loop beam functions for the transverse momentum distribution of the leading jet produced in association with an arbitrary colour-singlet system. Our results constitute the last missing ingredient for the calculation of the jet-vetoed cross section at small veto scales at the next-to-next-to-leading order, as well as an important ingredient for its resummation to next-to-next-to-next-to-leading logarithmic order. Our calculation is performed in the soft-collinear effective theory framework with a suitable regularisation of the rapidity divergences occurring in the phase-space integrals. We discuss the occurrence of soft-collinear mixing terms that might violate the factorisation theorem, and demonstrate that they are naturally absorbed into the beam functions at two loops in the exponential rapidity regularisation scheme when performing a multipole expansion of the measurement function. As in our recent computation of the two-loop soft function, we present the results as a Laurent expansion in the jet radius R. We provide analytic expressions for all flavour channels in x space with the exception of a set of R-independent non-logarithmic terms that are given as numerical grids. We also perform a fully numerical calculation with exact R dependence, and find that it agrees with our analytic expansion at the permyriad level or better. Our calculation allows us to define a next-to-next-to-leading order slicing method using the leading-jet pT as a slicing variable. As a check of our results, we carry out a calculation of the Higgs and Z boson total production cross sections at the next-to-next-to-leading order in QCD.

show abstract

“…For this reason, it is not immediately clear how to compare the results of ref. [74] with the ones presented here.…”

Section: Jhep04(2023)127mentioning

confidence: 65%

“…In the final stages of the preparation of this article, ref. [74] appeared with a numerical calculation of the beam functions in the quark channel. These results are obtained with a different rapidity regulator and computed for a discrete set of real points in the Mellin variable N conjugate to the longitudinal momentum x.…”

Section: Jhep04(2023)127mentioning

confidence: 99%

Quark and gluon two-loop beam functions for leading-jet pT and slicing at NNLO

Abreu

Gaunt

Monni

et al. 2023

J. High Energ. Phys.

View full text Add to dashboard Cite

show abstract

“…The beam function for quark initiated processes in the presence of a jet veto has also been presented in Mellin space in ref. [63].…”

Section: A Reduced Beam Functionsmentioning

confidence: 99%

Jet-veto resummation at N3LLp + NNLO in boson production processes

Campbell

Ellis

Neumann

et al. 2023

J. High Energ. Phys.

View full text Add to dashboard Cite

Vetoing energetic jet activity is a crucial tool for suppressing backgrounds and enabling new physics searches at the LHC, but the introduction of a veto scale can introduce large logarithms that may need to be resummed. We present an implementation of jet-veto resummation for color-singlet processes at the level of N3LLp matched to fixed-order NNLO predictions. Our public code MCFM allows for predictions of a single boson, such as Z/γ*, W± or H, or with a pair of vector bosons, such as W+W−, W±Z or ZZ. The implementation relies on recent calculations of the soft and beam functions in the presence of a jet veto over all rapidities, with jets defined using a sequential recombination algorithm with jet radius R. However one of the ingredients that is required to reach full N3LL accuracy is only known approximately, hence N3LLp. We describe in detail our formalism and compare with previous public codes that operate at the level of NNLL. Our higher-order predictions improve significantly upon NNLL calculations by reducing theoretical uncertainties. We demonstrate this by comparing our predictions with ATLAS and CMS results.

show abstract

Two-loop bottom mass effects on the Higgs transverse momentum spectrum in top-induced gluon fusion

Pietrulewicz

Stahlhofen

2023

J. High Energ. Phys.

View full text Add to dashboard Cite

We compute bottom mass (mb) corrections to the transverse momentum (qT) spectrum of Higgs bosons produced by gluon fusion in the regime qT ∼ mb ≪ mH at leading power in mb/mH and qT/mH, where the gluons couple to the Higgs via a top loop. To this end we calculate the quark mass dependence of the transverse momentum dependent gluon beam functions (aka gluon TMDPDFs) at two loops in the framework of SCET. These functions represent the collinear matrix elements in the factorized gluon-fusion cross section for small qT. We discuss in detail technical subtleties regarding rapidity regulators and zero-bin subtractions in the calculation of the virtual corrections present for massive quarks. Combined with the known soft function for mb ≠ 0 our results allow to determine the resummed Higgs qT distribution in the top-induced gluon fusion channel at NNLL′ (and eventually N3LL) with full dependence on mb/qT. We perform a first phenomenological analysis at fixed order, where the new corrections to the massless approximation lead to percent-level effects in the peak region of the Higgs qT spectrum. Upon resummation they may thus be relevant for state-of-the-art precision predictions for the LHC.

show abstract

The NNLO quark beam function for jet-veto resummation

Cited by 6 publications

References 76 publications

Quark and gluon two-loop beam functions for leading-jet pT and slicing at NNLO

Quark and gluon two-loop beam functions for leading-jet pT and slicing at NNLO

Jet-veto resummation at N3LLp + NNLO in boson production processes

Two-loop bottom mass effects on the Higgs transverse momentum spectrum in top-induced gluon fusion

Contact Info

Product

Resources

About