EFT-NLO · Two-loop renormalization of the SMEFT and the WET

Two-loop renormalization of the SMEFT and the WET

The search for physics beyond the Standard Model (BSM) has become one of the central goals of contemporary particle physics. While the Standard Model (SM) has been extraordinarily successful in describing a wide range of experimental results, it leaves key questions unresolved, such as the origin of dark matter, the matter–antimatter asymmetry, and the nature of neutrino masses. In the absence of direct discoveries of new particles at current collider experiments, indirect probes—through precise measurements and theoretical predictions—have emerged as one of the most powerful tools to uncover signs of new physics. The Standard Model Effective Field Theory (SMEFT) and the Weak Effective Theory (WET) provide a systematic framework to parameterize such potential effects of new physics in a model-independent way. They allow us to connect high-energy scales, where new physics may reside, with measurable low-energy observables. However, to achieve the precision necessary to match the experimental accuracy, the theoretical description must be extended beyond leading order. Recent work has established the one-loop matching between SMEFT and WET, but this result still suffers from unphysical scheme dependences that limit its applicability for robust phenomenological studies. This project directly addresses this need by advancing the theoretical toolkit to the next level of precision. The first objective is to compute the two-loop renormalization of the WET Wilson coefficients, which is necessary to eliminate the unphysical scheme dependence of the existing one-loop matching. This will be implemented in the public code Dsixtools, ensuring immediate accessibility and usability for the wider community. The second objective is to extend this precision program to SMEFT itself, by performing the full two-loop renormalization of its parameters. Central to this effort is the calculation of the Anomalous Dimension Matrix (ADM), which governs the scale dependence of the SMEFT Wilson coefficients. At this level, a significantly larger set of operators becomes phenomenologically relevant, thereby greatly enhancing the reach of precision studies in constraining new physics. The pathway to impact of this project lies in enabling the first consistent, fully general next-to-leading order (NLO) analysis of SMEFT parameters. Once the one-loop matching from general BSM theories onto SMEFT becomes available—which is expected imminently—the combination with the results of this project will allow the community to perform systematic, model-independent analyses at unprecedented precision. This will sharpen the interpretive power of experimental results from the LHC, flavor experiments, and low-energy precision measurements, thereby advancing one of the highest strategic priorities in fundamental physics: the search for new physics beyond the Standard Model. The expected impacts are significant in scale and scope. On the scientific side, the project will provide the essential theoretical foundation for precision frontier studies worldwide, directly supporting the physics programs of major experimental collaborations. On the broader strategic level, it will contribute to maintaining Europe’s and the international community’s leadership in precision theoretical physics, ensuring that we are fully equipped to interpret upcoming experimental data in the most general and reliable way possible. By eliminating key theoretical limitations and opening the door to consistent global analyses, the project aims to substantially strengthen the global effort to uncover the fundamental laws of nature.

Текст от CORDIS, на английски · Данни: CORDIS, © Европейски съюз