Anti-CKM (aa 282-381) polyclonal antibody

The precise measurement of the CKM angle phi(3) is important to further test the Standard Model description of CP violation. The small values of the branching fractions of the decays involved in the measurement limit the precision, hence a larger dataset has to be accumulated to improve the precision. The Belle II experiment at the SuperKEKB asymmetric-energy e(+)e(-) collider aims to collect 50 ab(-1) of data, a factor of 50 more than that of its predecessor Belle. The accelerator has been successfully commissioned in 2016 and the first physics collisions were recorded in April 2018. The best sensitivity to phi(3) can be achieved by harnessing all possible final states of B -> D-(*K-)(()*()) decays. With the full dataset, Belle II is expected to achieve a precision of 1 degrees for the angle phi(3). The expected sensitivities and rediscoveries from 2018 data are presented here.

Due to a recent more precise evaluation of V-ud and V-us, the unitarity condition of the first row in the Cabibbo-Kobayashi-Maskawa (CKM) matrix: vertical bar V-ud vertical bar(2) +vertical bar V-us vertical bar(2) +vertical bar V-ub vertical bar(2) = 0.99798 +/- 0.00038 now stands at a deviation more than 4 sigma from unity. Furthermore, a mild excess in the overall Higgs signal strength appears at about 2 sigma above the standard model (SM) prediction, as well as the long-lasting discrepancy in the forward-backward asymmetry A(FB)(b) in Z -> b (b) over bar at LEP. Motivated from the above three anomalies we investigate an extension of the SM with vector-like quarks (VLQs) associated with the down-quark sector, with the goal of alleviating the tension among these datasets. We perform global fits of the model under the constraints coming from the unitarity condition of the first row of the CKM matrix, the Z -pole observables A(FB)(b), R-b and Gamma(had), Electro-Weak precision observables Delta S and Delta T, B-meson observables B-d(0)-(B) over bar (0)(d) mixing, B+ -> pi(+)l(+)l(-) and B-0 -> mu(+)mu(-), and direct searches for VLQs at the Large Hadron Collider (LHC). Our results suggest that adding VLQs to the SM provides better agreement than the SM.