Motivated by renewed evidence for new physics in $b to sellell$ transitions in the form of LHCbs new measurements of theoretically clean lepton-universality ratios and the purely leptonic $B_stomu^+mu^-$ decay, we quantify the combined level of discr
epancy with the Standard Model and fit values of short-distance Wilson coefficients. A combination of the clean observables $R_K$, $R_{K^*}$, and $B_sto mumu$ alone results in a discrepancy with the Standard Model at $4.0sigma$, up from $3.5sigma$ in 2017. One-parameter scenarios with purely left-handed or with purely axial coupling to muons fit the data well and result in a $sim 5 sigma$ pull from the Standard Model. In a two-parameter fit of %$C_9$ and $C_{10}$, new-physics contributions with both vector and axial-vector couplings to muons the allowed region is much more restricted than in 2017, principally due to the much more precise result on $B_s to mu^+ mu^-$, which probes the axial coupling to muons.Including angular observables data restricts the allowed region further.A by-product of our analysis is an updated average of $text{BR}(B_s to mu^+ mu^-) = (2.8pm 0.3) times 10^{-9}$.
We consider the impact on WW production of the unique dimension-six operator coupling gluons to the Higgs field. In order to study this process, we have to appropriately model the effect of a veto on additional jets. This requires the resummation of
large logarithms of the ratio of the maximum jet transverse momentum and the invariant mass of the W boson pair. We have performed such resummation at the appropriate accuracy for the Standard Model (SM) background and for a signal beyond the SM (BSM), and devised a simple method to interface jet-veto resummations with fixed-order event generators. This resulted in the fast numerical code MCFM-RE, the Resummation Edition of the fixed-order code MCFM. We compared our resummed predictions with parton-shower event generators and assessed the size of effects, such as limited detector acceptances, hadronisation and the underlying event, that were not included in our resummation. We have then used the code to compare the sensitivity of WW and ZZ production at the HL-LHC to the considered higher-dimension operator. We have found that WW can provide complementary sensitivity with respect to ZZ, provided one is able to control theory uncertainties at the percent-level. Our method is general and can be applied to the production of any colour singlet, both within and beyond the SM.
