Update of Heavy Flavor Averages: Persistent 3σ Tension in R(D)-R(D*)

February 18, 2026
Messungen von R(D) und R(D∗) und deren zweidimensionaler Mittelwert. PRD
Measurements of R(D) and R(D∗) and their two-dimensional average. Contours correspond to 68% CL. An average of the theoretical predictions and the experimental average deviate from each other by about 3.14σ.

The Heavy Flavor Averaging Group (HFLAV) provides regular updates to the world averages of heavy flavor quantities. Dr. Pablo Goldenzweig of ETP has been a member of the Rare B decays sub-group since 2015 and has contributed to all updates, and to the development and maintenance of the averaging software. 

The most recent publication entitled Averages of b-hadron, c-hadron, and tau-lepton properties as of 2023 was just published by PRD as an Editors’ Suggestion and is featured on the PRD homepage alongside other highlighted articles. The representative figure is the new R(D)-R(D*) plot, where the average of the SM predictions and the experimental average deviate by approximately 3 standard deviations. 

Our results include preliminary results not included by PDG says Dr. Goldenzweig. We have also recently added a feature where one can create their own plot displaying averages of specific decays of interest for B hadron decays into open or hidden charm hadrons and for rare B meson decays.

Contact: Dr. Pablo Goldenzweig (pablo goldenzweig ∂does-not-exist.kit edu)