Related papers: Shifting $R_b$ with $A^b_{FB}$
We report the first measurement of the forward-backward asymmetry and the ratios of Wilson coefficients $A_9/A_7$ and $A_{10}/A_7$ in $B \to K^* \ell^+ \ell^-$, where $\ell$ represents an electron or a muon. We observe a large integrated…
New results in processes with an underlying quark transition $b\to s \ell^+\ell^-$ have been recently reported by the LHCb and Belle II collaborations. In this note we show how the main implications of a handful of new measurements can be…
The theory of heavy meson masses, in which the symmetries of heavy and light quarks are exploited, can be used to describe the low energy interaction among heavy mesons to a better extent. The spin-flavor symmetry leads to many interesting…
The bottom quark forward-backward asymmetry $A_{\rm{FB}}$ is a key observable in electron-positron collisions at the $Z^{0}$ peak. In this paper, we employ the Principle of Maximum Conformality (PMC) to fix the $\alpha_s$-running behavior…
In this paper, forward-backward asymmetry and differential cross section of top quark in flavor violating $Z'$ model up to $\mathscr{O}(\alpha_s^2 \alpha_X)$ at Tevatron are calculated. In order to account for the top observed large…
We investigate the effect of non-degenerate quarks on $B_K$. This effect is noticeably large for $B_K$ (significantly larger than statistical uncertainty). Hence, it is important to include this effect in order to determine $B_K$ with…
A larger than expected forward-backward asymmetry in rapidity is observed in top quark pairs produced in proton-antiproton collisions at the Tevatron. The asymmetry is seen in both the top quark distribution $A_{FB}^t$ and in the…
We consider the extension of the standard model with an arbitrary number of U(1) gauge fields coupled to baryon-minus-lepton number and/or hypercharge. Under the assumption that A^b_FB from the LEP1 experiment is an unlucky fluctuation, we…
Results from heavy flavour electroweak physics at LEP1 are reviewed together with measurements of 2-fermion processes at LEP2. For the former measurements the emphasis is on analyses of heavy quark forward-backward asymmetries, A_FB^b,c,…
In this talk I discuss the effects of physics beyond the standard model on the process $Z \to b\bar{b}$. I argue that, because the top-quark is heavy, this process is susceptible to large corrections from new physics.
We discuss the phenomenological imprints of modifications to gravity in the early universe with a specific focus on the time of recombination. We derive several interesting results regarding the effect that such modifications have on…
We review the current status of theoretical predictions for mixing quantities and lifetimes in the $B$-sector. In particular, due to the first non-zero measurement of the decay rate difference in the neutral $B_s$-system, $\Delta \Gamma_s/…
In a series of three lectures, I review the theory and phenomenology of heavy quark masses and mixing angles and the status of their determination. In addition, I give an introduction to heavy quark symmetry, with the main emphasis on the…
Various extensions of the Standard Model, i.e. string inspired groups like E_6, extra dimensions, 'deconstruction', predict additional vector bosons. In most cases these bosons can mix with the SM Z and this translates into a very high…
Recent observations discovered that some repeating fast radio bursts (FRBs) show complicated variations and reversals of Faraday rotation measures (RMs), indicating that the sources of these FRBs are embedded in a dynamically magnetized…
The mass spectra and electromagnetic decay rates of charmonium, bottomonium and B_c mesons are comprehensively investigated in the relativistic quark model. The presence of only heavy quarks allows the expansion in powers of their…
Stringent relations between the $B^{(*)} \to D^{(*)} $ form factors exist in the heavy quark limit and the leading symmetry breaking corrections are known. We reconsider their uncertainty and role in the analysis of recent Belle data for…
We extend our relativistic quark model to the study of the decay Lambda_b -> Lambda_c ell nu and verify that the model satisfies the heavy-quark symmetry constraints at order 1/mQ^2. We isolate a strong dependence on a parameter which…
These lectures review the progress made in our present understanding of $B$ decays. The emphasis here is on applications of QCD to $B$ decays and the attendant perturbative and non-perturbative uncertainties, which limit present theoretical…
The environment of actively repeating fast radio bursts (FRBs) has been shown to be complex and varying. The recently localized FRB 20190520B is extremely active, has the largest confirmed host dispersion measure, and is only the second FRB…