Related papers: Probing new physics in rare charm processes
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^-…
The experimental information on b --> s l^+ l^- decays has grown enormously during the last couple of years due to BaBar, Belle, CDF and LHCb. Especially, exclusive modes B --> K^(*) l^+ l^-, which have the largest rate and are easily…
The $c \to u \gamma$ transition does not occur at the tree level in the Standard Model and is strongly GIM-suppressed at one loop. The leading QCD logarithms are known to enhance the amplitude by two orders of magnitude. We point out that…
The search for new physics beyond the standard model is proceeding nowadays intensively along experimental and theoretical lines. We review here the sector of charm radiative decays in this context. The calculation of $D\to V\gamma$, $D\to…
We study the neutral current flavour changing rare decay mode $B\to K \gamma \gamma $ within the framework of Standard Model, including the long distance contributions. It is found that these long distance contributions can larger than the…
We perform a comprehensive study of a number of rare charm decays, incorporating the first evaluation of the QCD corrections to the short distance contributions, as well as examining the long range effects. For processes mediated by the…
The LHCb experiment, bolstered up by the 10^12 b-hadrons to be produced yearly in its interaction region, is an excellent place to study rare B decays. Flavor-changing neutral currents are forbidden at tree level in the Standard Model. They…
We propose a novel method to study flavor-changing neutral currents in the $e^+e^-\to D^{*0}$ and $e^+e^-\to B_{s}^* $ transitions, tuning the energy of $e^+e^-$- collisions to the mass of the narrow vector resonance $D^{*0}$ or $ B_{s}^*$.…
We search for rare FCNC charm decays of the form $X_c^+\to h^+\llp$, where $X_c^+$ is a charm hadron, $h$ is a pion, kaon or proton, and $\ell^{(}{'}^{)}$ is an electron or a muon. In the pion and kaon modes, we study both $D^+$ and $D_s^+$…
Rare decays were essential in the discovery of the CKM mechanism of flavour and CP violation and are highly sensitive probes of physics beyond the Standard Model. In this summary the current status and future prospects of experimental…
Lattice QCD calculations in charm and bottom physics are particularly important because they can provide the hadronic weak decay matrix elements needed for key constraints on the CKM Unitarity Triangle. I will summarise recent results in…
Motivated by recent experimental results on charm physics we investigate implications of the updated constraints of new physics in rare charm meson decays. We first reconsider effects of the MSSM in $c\to u \gamma$ constrained by the recent…
A search for the flavor-changing neutral-current decay $\Lambda_{c}^{+} \to p\mu^+\mu^-$ is reported using a data set corresponding to an integrated luminosity of $3.0\rm fb^{-1}$ collected by the LHCb collaboration. No significant signal…
Rare $|\Delta c|=|\Delta u|=1$ transitions into dineutrinos are strongly GIM-suppressed and constitute excellent null tests of the standard model. While branching ratios of $D \to P \,\nu \bar \nu$, $D \to P^+ P^- \, \nu \bar \nu$, $P=\pi,…
We propose to investigate flavour changing neutral currents in the $c \to u \gamma$ transition through the measurement of the difference between $\Gamma (D^0 \to \rho^0 \gamma)$ and $\Gamma (D^0 \to \omega \gamma)$. This is based on the…
The flavor-changing neutral current decay B_s->mu mu is highly suppressed in the standard model, but its branching fraction of 3.4*10^-9 could be significantly enhanced through contributions from new physics. At the LHC, this rare decay…
We present a calculation of the rare decay modes D^0 -> e^+ e^- gamma and D^0 -> mu^+ mu^- gamma in the framework of Standard Model. For the short distance part, we have derived QCD corrections to the Wilson coefficients involved, including…
The minimal supersymmetric standard model (MSSM) with universal soft breaking terms has a negligible effect on the rare $c\to u\gamma$ decay rate. We therefore study a general model with non-universal soft breaking terms constrained by…
LHCb, bolstered up by the 10^12 b-hadrons produced yearly, is an excellent place to study rare B decays. The B_s to mu^+ mu^- decay, generated by flavour-changing neutral current, is strongly suppressed within the Standard Model (SM).…
Top flavour-changing neutral decays are extremely suppressed within the Standard Model (SM) by the GIM mechanism, but can reach observable rates in some of its extensions. We compute the branching ratios for t -> c gamma and t -> c g in…