Quark Transverse Parton Distribution at the Next-to-Next-to-Next-to-Leading Order

110

126

We compute the quark and gluon transverse momentum dependent parton distribution functions at next-to-next-to-next-to-leading order (N3LO) in perturbative QCD. Our calculation is based on an expansion of the differential Drell-Yan and gluon fusion Higgs production cross sections about their collinear limit. This method allows us to employ cutting edge multiloop techniques for the computation of cross sections to extract these universal building blocks of the collinear limit of QCD. The corresponding perturbative matching kernels for all channels are expressed in terms of simple harmonic polylogarithms up to weight five. As a byproduct, we confirm a previous computation of the soft function for transverse momentum factorization at N3LO. Our results are the last missing ingredient to extend the qT subtraction methods to N3LO and to obtain resummed qT spectra at N3LL′ accuracy both for gluon as well as for quark initiated processes.

Section: Jhep09(2020)146mentioning

confidence: 80%

Section: Jhep09(2020)146mentioning

confidence: 99%

Section: Jhep09(2020)146mentioning

confidence: 99%

See 1 more Smart Citation

Transverse momentum dependent PDFs at N3LO

Ebert

Mistlberger

Vita

2020

110

126

“…The calculations of the TMD beam and soft functions can be carried out with a rapidity regulator, while the physical results are independent of the choice of such a regulator. The two-loop analytic results for these TMD beam and soft functions can be found in [95][96][97][98][99][100], and the N 3 LO results have been obtained very recently [101,102]. On the other hand, the hard function H a is process dependent.…”

Section: The Class-a Partmentioning

confidence: 83%

The gluon-fusion production of Higgs boson pair: N3LO QCD corrections and top-quark mass effects

Chen

Shao

et al. 2020

The Higgs boson pair production via gluon fusion at high-energy hadron colliders, such as the LHC, is vital in deciphering the Higgs potential and in pinning down the electroweak symmetry breaking mechanism. We carry out the next-to-next-to-next-toleading order (N 3 LO) QCD calculations in the infinite top-quark mass limit and present predictions for both the inclusive and differential cross sections. Such corrections are indispensable in stabilising the perturbative expansion of the cross section in the strong coupling α s . At the inclusive level, the scale uncertainties are reduced by a factor of four compared with the next-to-next-to-leading order (NNLO) results. Given that the inclusion of the top-quark mass effects is essential for the phenomenological applications, we use several schemes to incorporate the N 3 LO results in the infinite top-quark mass limit and the nextto-leading order (NLO) results with full top-quark mass dependence, and present theoretical predictions for the (differential) cross sections in the proton-proton collisions at the centreof-mass energies √ s = 13, 14, 27 and 100 TeV. Our results provide one of the most precise theoretical inputs for the analyses of the Higgs boson pair events.

“…In contrast to the TMD beam functions, which are based on the same collinear limit and at N 3 LO can be entirely expressed in terms of harmonic polylogarithms up to weight 5 [98,111], the T N beam functions have a much richer structure of the appearing functions and are expressed in terms of Goncharov polylogarithm, as well as iterated integrals with letters that involve square roots. It will be interesting to better understand the source of this difference.…”

Section: Discussionmentioning

confidence: 99%

N-jettiness beam functions at N3LO

Ebert

Mistlberger

Vita

2020

We present the first complete calculation for the quark and gluon N-jettiness ($$ {\mathcal{T}}_N $$ T N ) beam functions at next-to-next-to-next-to-leading order (N3LO) in perturbative QCD. Our calculation is based on an expansion of the differential Higgs boson and Drell-Yan production cross sections about their collinear limit. This method allows us to employ cutting edge techniques for the computation of cross sections to extract the universal building blocks in question. The class of functions appearing in the matching coefficents for all channels includes iterated integrals with non-rational kernels, thus going beyond the one of harmonic polylogarithms. Our results are a key step in extending the $$ {\mathcal{T}}_N $$ T N subtraction methods to N3LO, and to resum $$ {\mathcal{T}}_N $$ T N distributions at N3LL′ accuracy both for quark as well as for gluon initiated processes.