Speaker
Cameron Voisey
(University of Cambridge)
Description
The high-energy tails of charged and neutral-current Drell-Yan (DY) processes provide important constraints on the light quark and antiquark parton distribution functions (PDFs) in the large-$x$ region. On the other hand, a hypothetical short-distance new physics would smoothly distort the high-energy tails as described by the Standard Model Effective Field Theory (SMEFT). In this work, we assess for the first time the interplay between PDF and EFT effects in high-mass DY at the LHC. We determine the extent to which EFT signals that would manifest themselves in the tails of the DY distributions could be reabsorbed into the large-$x$ (anti)quark PDFs, and present a strategy aimed at disentangling possible new physics effects from proton structure modifications. We quantify the impact that a consistent joint determination of the PDFs and Wilson Coefficients has in two motivated short-distance new physics scenarios: 1) electroweak oblique corrections ($\hat{W}$, $\hat{Y}$) and 2) four-fermion interactions possibly behind the LHCb anomalies in $R(K^{(*)})$. Finally, we present dedicated projections for the High-Luminosity LHC and evaluate its ultimate potential to constrain the EFT parameters, while taking into account potential modifications of the proton structure.
Primary authors
Admir Greljo
(Universität Bern)
Cameron Voisey
(University of Cambridge)
James Moore
(University of Cambridge)
Juan Rojo
(Vrije Universiteit Amsterdam)
Maeve Madigan
(University of Cambridge)
Maria Ubiali
(University of Cambridge)
Shayan Iranipour
(University of Cambridge)
Zahari Kassabov
(University of Cambridge)