相关论文: Rare FCNC top, beauty and charm decays
Flavour-changing neutral-current processes, such as $b\to s \ell^+\ell^-$, are forbidden at tree level in the Standard Model and hence might receive comparatively large corrections from new particles. This document highlights recent…
We investigate flavor-changing neutral current (FCNC) interactions of the top quark at a future muon collider with a center-of-mass energy of $\sqrt{s} = 10~\mathrm{TeV}$. The process $\mu^{+}\mu^{-} \to \nu_{\mu}\,\mu^+\,b\,j$ and its…
Flavor-changing neutral current (FCNC) top-quark decays are highly suppressed due to the Glashow-Iliopoulos-Maiani mechanism in the standard model (SM). If $t\to q h, qV$ with $V=g,\gamma, Z$ are all induced via quantum loop levels, then we…
Flavour-changing neutral current (FCNC) interactions between the Higgs boson and the top quark are subject to significant suppression within the Standard Model (SM). Consequently, these interactions can only attain an observable level…
In the littlest Higgs model with T-parity (LHT) the newly introduced mirror quarks have flavor-changing couplings with the Standard Model (SM) quarks and may enhance the flavor-changing neutral-current (FCNC) top quark interactions which…
Standard Model $t\bar t$ samples in ATLAS and CMS provide an opportunity to conduct measurements of the polarization of quarks produced in top-quark decays. The bottom quarks from the $t \to W^+ b$ decays, as well as the charm, strange, up…
Searches for flavor changing neutral current (FCNC) processes in top-quark production and decays by the ATLAS Collaboration are presented. Data collected from $pp$ collisions at the LHC at a centre-of-mass energy of 7 TeV during 2011,…
This review discusses the present experimental and theoretical status of rare flavour-changing neutral current $b$-quark decays at the begin of 2018. It includes a discussion of the experimental situation and details of the currently…
We calculate flavor-changing neutral current (FCNC) processes with top-quark production via anomalous couplings at LHC energies. We report on progress on the FCNC processes gu -> tZ, gu -> t gamma and gu -> tg. We go beyond leading order…
In this paper, we study the observability of the top-Higgs flavor changing neutral current (FCNC) $tqh$ coupling through the process $pp\to qg\to t(\to \ell^{+}b\nu)h(\to \gamma\gamma)$ at the Large Hadron Collider~(LHC), where $\ell=e,…
Models with a non-universal Z' exhibit in general flavor changing neutral currents (FCNC) at tree-level. When the Z' couplings favor the third generation, flavor changing transitions of the form Z'tc and Z'tu could be large enough to be…
We propose the $B_c\to B_u^*\gamma$ decay as the most suitable probe for the flavour changing neutral transition $c\to u\gamma$. We estimate the short and long distance contributions to this decay within the standard model and we find them…
We show that the study of CP asymmetries in neutral B-meson decays provides a very sensitive probe of flavour-changing neutral currents (FCNC). We introduce two new angles, $\alpha_{SM}$ and $\beta_{SM}$, whose main feature is that they can…
We study the implications of flavour-changing neutral currents (FCNC's) in a model with the $SU(2)_l\times SU(2)_h\times U(1)_Y$ electroweak gauge symmetry for several anomalies appearing in $b\to s \ell\bar \ell$ induced $B$ decays in LHCb…
FCC-hh is a proposed future energy-frontier hadron collider, which goal is to provide high luminosity proton collisions at a centre-of-mass energy of 100 TeV. The FCC-hh has an extremely rich physics program ranging from standard model (SM)…
We revisit rare radiative leptonic decays $B_{s,d}\to \gamma e^+e^-$ and $B_{s,d}\to \gamma \mu^+\mu^-$ in the Standard Model and provide the updated estimates for various differential distributions (the branching ratios, the…
We analyze the potential of rare charm decays as probes of new physics at a high-luminosity flavor facility operating at the $Z$ pole, such as the FCC-ee or CEPC. In particular, we identify clean null-test observables in $D^0 \to \pi^+…
We study the one-loop contribution of the effective flavor changing neutral couplings (FCNC) $tcZ$ to the charm quark electric dipole moment. Using the known limits on the top and charm quarks electric dipole moments, we place limits on…
The rare top decay t-> c l+l-, which involves flavor violation, is studied as a possible probe of new physics. This decay is analyzed with the simplest Standard Model extensions with additional gauge symmetry formalism. The considered…
We determine the constraints on the anomalous top-quark coupling associated with the flavor-changing neutral current vertex $\bar t c \gamma $ from the limits on the $b$-quark rare decay $b\rightarrow s \gamma$ and non-standard top-quark…