No Arabic abstract
Some fine differences between the twin $b$-flavored unitarity triangles are calculated by means of a generalized Wolfenstein parametrization of the CKM matrix, and a possibility of experimentally establishing the second triangle is briefly discussed. We find that the apexes of these two triangles, characterized respectively by $(overline{rho}, overline{eta})$ and $(widetilde{rho}, widetilde{eta})$, are located on the same circular arc in the complex plane. This observation provides us with a new way to test consistency of the CKM picture of CP violation in the quark sector and probe possible new physics. The differences between the apexes (i.e., $widetilde{rho} - overline{rho}$ and $widetilde{eta} - overline{eta}$) are found to be of ${cal O}(lambda^2)$ with $lambda simeq 0.22$ being the Wolfenstein expansion parameter, and the shapes of these two triangles are found to be insensitive to the two-loop renormalization-group-equation running effects up to the accuracy of ${cal O}left(lambda^4right)$.
This report contains the results of the Workshop on the CKM Unitarity Triangle, held at CERN on 13-16 February 2002 to study the determination of the CKM matrix from the available data of K, D, and B physics. This is a coherent document with chapters covering the determination of CKM elements from tree level decays and K and B meson mixing and the global fits of the unitarity triangle parameters. The impact of future measurements is also discussed.
Stimulated by the exciting progress in experiments, we carry out a combined analysis of the masses, and strong and radiative decay properties of the $B$ and $B_s$-meson states up to the second orbital excitations. Based on our good descriptions of the mass and decay properties for the low-lying well-established states $B_1(5721)$, $B_2^*(5747)$, $B_{s1}(5830)$ and $B_{s2}^*(5840)$, we give a quark model classification for the high mass resonances observed in recent years. It is found that (i) the $B_{J}(5840)$ resonance may be explained as the low mass mixed state $B(|SDrangle_L)$ via $2^3S_1$-$1^3D_1$ mixing, or the pure $B(2^3S_1)$ state, or $B(2^1S_0)$. (ii) The $B_J(5970)$ resonance may be assigned as the $1^3D_3$ state in the $B$ meson family, although it as a pure $2^3S_1$ state cannot be excluded. (iii) The narrow structure around 6064 MeV observed in the $B^+K^-$ mass spectrum at LHCb may be mainly caused by the $B_{sJ}(6109)$ resonance decaying into $B^{*+}K^-$, and favors the assignment of the high mass $1D$-wave mixed state $B_s(1D_2)$ with $J^P=2^-$, although it as the $1^3D_3$ state cannot be excluded. (iv) The relatively broader $B_{sJ}(6114)$ structure observed at LHCb may be explained with the mixed state $B_s(|SDrangle_H)$ via $2^3S_1$-$1^3D_1$ mixing, or a pure $1^3D_1$ state. Most of the missing $1P$-, $1D$-, and $2S$-wave $B$- and $B_s$-meson states have a relatively narrow width, they are most likely to be observed in their dominant decay channels with a larger data sample at LHCb.
We give a review of the status of the global effort to measure the sides of the CKM Unitarity Triangle.
We investigate the impact of extra leptons on observed tensions in the muon $g-2$ and the first-row CKM unitarity. By introducing a new SU(2)$_L$ doublet lepton and a SU(2)$_L$ triplet lepton, we find that both of the tensions can be explained simultaneously under constraints from electroweak precision observables and Higgs-boson decays. Our model could be tested by measurements of $htomumu$ at future collider experiments.
The Fermi constant ($G_F$) is extremely well measured through the muon lifetime, defining one of the key fundamental parameters in the Standard Model (SM). Therefore, to search for physics beyond the SM (BSM) via $G_F$, the constraining power is determined by the precision of the second-best independent determination of $G_F$. The best alternative extractions of $G_F$ proceed either via the global electroweak (EW) fit or from superallowed $beta$ decays in combination with the Cabibbo angle measured in kaon, $tau$, or $D$ decays. Both variants display some tension with $G_F$ from muon decay, albeit in opposite directions, reflecting the known tensions within the EW fit and hints for the apparent violation of CKM unitarity, respectively. We investigate how BSM physics could bring the three determinations of $G_F$ into agreement using SM effective field theory and comment on future perspectives.