Related papers: Unparticle effects in rare (t -> c g g) decay
Rare decays mediated by $b \to s \nu \bar \nu$ transitions have been reported by the Belle II experiment. The branching ratio of the decay $B^+ \to K^+ \nu \bar \nu$ is found to be enhanced with respect to the standard model value. If taken…
Unparticle physics from a hidden conformal sector can alter the evolution of the Standard Model (SM) gauge couplings via TeV scale threshold corrections. We discuss how this may lead to gauge coupling unification at M_{GUT}\approx 2 \times…
B physics represents a privileged place to look for supersymmetry (SUSY) through its virtual effects. Here we discuss rare B decays ($b \to s \gamma$, $b \to s g$, $b \to s l^{+} l^{-}$) and $B-\bar{B}$ oscillations in the context of…
In these four lectures I review the theory and phenomenology of weak decays of quarks, and their r\^ole in the determination of the parameters of the Standard Model of particle physics, in testing subtle features of the theory and in…
We explore phenomenological consequences of coupling a non-conformal scale-invariant theory to the standard model. We point out that, under certain circumstances, non-conformal scale-invariant theories have oscillating correlation functions…
We report the results of the first computation related to the study of the spectator effects in the rare decay mode $B\to K \gamma \gamma $ within the framework of Standard Model. It is found that the account of these effects results in the…
The direct searches for Beyond Standard Model (BSM) particles have been constraining their mass scale to the extent where it is now becoming consensual that such particles are likely to be above the energy reach of the LHC. Meanwhile, the…
In the Minimal Supersymmetric Standard Model (MSSM), there are numerous sources of flavour-violation in addition to the usual Kobayashi-Maskawa mixing matrix of the Standard Model. We reexamine the renormalisation group equations (RGEs)…
We study flavour-changing neutral current decays of the top quark in the democratic Three Higgs Doublet Model featuring a $Z_3$-symmetric scalar potential and Natural Flavour Conservation. In this framework, while such processes are absent…
We derive analytical expressions for the shape of the invariant mass distributions of massless Standard Model endproducts in cascade decays involving massive New Physics (NP) particles, D -> Cc -> Bbc -> Aabc, where the final NP particle A…
We study the implications on flavor changing neutral current and CP violating processes in the context of supersymmetric theories without a new flavor structure (flavor blind supersymmetry). The low energy parameters are determined by the…
Continuing earlier work, we examine the constraint on an anomalous t-c-g coupling from top quark decay. We find that from current CDF measurements of the branching ratio $t \rightarrow W b$, the minimum scale at which new physics can…
In this paper we consider CP-violating new-physics contributions to the decay $t \to b \bar b c$. We examine the prospects for detecting such new physics at the LHC, which requires studying the process $gg \to t (\to b \bar b c) \bar t (\to…
The measurements of rare decays are highly sensitive to physics beyond the standard model. In this article limits on the branching ratios of the decays B0s -> mu+mu-, D0 -> mu+mu- and D+ -> pi+mu+mu- are presented. Furthermore the first…
The rare decays $B_{s(d)} \to \mu^+\mu^-$ play a key role for the testing of the Standard Model. An overview of the most recent theoretical predictions of the corresponding branching ratios is given, emphasizing that the sizable decay width…
The experimental measurements of flavor-changing neutral-current B-meson decays governed by b --> s + (gamma, l^+ l^-) transitions have entered a new level of precision. Recent results by Belle, CDF, Babar, and LHCb on B -->K^(*) l^+ l^-…
In the present work we study the effects of an unparticle $\unpart$ as the possible source of missing energy in the decay $B \to K (K^*) + {\rm missing energy}$. We find that the dependence of the differential branching ratio on the…
We examine the commonly explored beyond-standard-model physics scenario of secret neutrino forces, and point out a model prediction that appears to have been overlooked: the generation of unique flavor-changing effects in experiments…
Virtual effects induced by new physics in rare Z decays are reviewed. Since the expected sensitivity of the giga-Z linear collider is of the order of $10^{-8}$, we emphasize the importance of any new physics effect that gives a prediction…
The implications of the latest measurement of the branching fraction of B($ b\rightarrow s \gamma $) of b hadrons, which is another signature of New Physics beyond Standard Model is presented here. The quark transitions $ b \rightarrow s $,…