Update of the Unitarity Triangle Analysis

TL;DR

This paper updates the Unitarity Triangle analysis within the Standard Model and explores potential New Physics effects, finding no significant NP signals except a hint in B_s-ar B_s mixing, and setting bounds on NP scales.

Contribution

It provides the latest comprehensive UT analysis, including constraints on NP effects and bounds on =2 effective Hamiltonian coefficients, extending previous work.

Findings

CKM matrix is the main source of flavor mixing and CP violation.

No significant NP effects in K-arnd B_d-ar mixing.

Hint of NP in B_s-ar_s mixing at 2.9 sigma.

Abstract

We present the update of the Unitarity Triangle (UT) analysis within the Standard Model (SM) and beyond. Within the SM, combining the direct measurements on sides and angles, the UT turns out to be overconstraint in a consistent way, showing that the CKM matrix is the dominant source of flavour mixing and CP-violation and that New Physics (NP) effects can appear at most as small corrections to the CKM picture. Generalizing the UT analysis to investigate NP effects, constraints on b -> s transitions are also included and both CKM and NP parameters are fitted simultaneously. While no evidence of NP effects is found in K-\bar K and B_d-\bar B_d mixing, in the B_s-\bar B_s mixing an hint of NP is found at the 2.9 \sigma level. The UT analysis beyond the SM also allows us to derive bounds on the coefficients of the most general \Delta F=2 effective Hamiltonian, that can be translated into bounds on the NP scale.