- The paper presents a successful combination of NNLO QCD and NLO electroweak corrections in FEWZ, significantly enhancing precision in dilepton production predictions.
- It employs a complex-mass scheme to incorporate gauge boson self-energy corrections, maintaining gauge invariance without relying on resummation.
- The improved simulation framework is validated against established literature, enabling more precise modeling of LHC processes including photon-induced effects.
Combining QCD and Electroweak Corrections to Dilepton Production in FEWZ
The paper presents a significant contribution to the precision of theoretical predictions for the Drell-Yan (DY) process, which is essential for LHC analyses. The authors detail the integration of next-to-next-to-leading order (NNLO) QCD corrections with next-to-leading order (NLO) electroweak (EW) corrections within the FEWZ simulation code framework. This approach is pivotal in achieving the level of accuracy required for percent-level measurements, notably in scenarios where electroweak corrections become large.
The DY process is pivotal in high-energy physics both for its role in precision measurements and as a potential window to new physics. The primary source of higher-order corrections arises from real photon emissions and weak boson exchanges, necessitating an inclusive treatment within computational tools. The paper describes the calculation and incorporation of one-loop electroweak corrections using complex mass schemes for lepton pairs produced through the Drell-Yan mechanism and includes both massless and massive leptonic final states.
A key advantage of the FEWZ implementation is its focus on maintaining theoretical consistency. By using complex masses in self-energy insertions of gauge bosons and leveraging the complex-mass scheme (CMS) for calculations, it preserves gauge invariance without the need for resummation frameworks, which can violate gauge principles if not handled correctly. The authors provide comprehensive numerical analyses verifying the NLO EW corrections against established literature values, using both the CMS and the pole scheme for their studies.
The paper's results achieve precision by accounting for the combined effects of QCD and EW corrections, thus eliminating the need for separate implementations of final-state radiation and Sudakov logarithms when confronting experimental data with theory. The CMS in particular ensures stability against higher-order corrections, making it the authors' preferred option for parameter consistency.
The phenomenological outcomes of the study are broadly applicable, extending to studies involving arbitrary kinematic distributions and photon radiation distinctions within the LHC environment. Photon-induced processes form a small, yet non-negligible correction, detectable especially in high-energy regions, validating the importance of including these channels in theoretical predictions.
In addressing the implications, the research enhances the utility of W/Z production simulations, where the precise modeling of higher-order effects directly correlates with experimental validations, essential for both legacy and new physics searches. The integration also aligns with ongoing efforts to combine NLO QCD plus parton-shower effects with EW corrections, thus providing a comprehensive toolset for theoretical-experimental convergences.
Future developments could leverage this work to integrate these corrections more seamlessly across broader regions of LHC operation, potentially exploring varying collision energies or extended initial and final-state resolution settings. Continuing to refine parton distribution functions and coupling schemes in line with this study could further optimize predictions for increasingly precise experimental results.
In summary, this work exemplifies the convergence of computational methods, theoretical rigor, and experimental validation, fortifying the predictive power of simulations in particle physics. It marks a beneficial progression towards analytically tractable yet rigorous computations, meeting the growing demands for accuracy in large-scale collider experiments.