Related papers: Improved Upper Limits on Baryon-Number Violating D…
The spectrum of electrons from muons decaying in an atomic bound state is significantly modified by their interaction with the nucleus. Somewhat unexpectedly, its first measurement, at the Canadian laboratory TRIUMF, differed from basic…
We consider the exclusive decays $B \to D^{(*)}\,\ell \bar\nu$ and study the effect of non $V-A$ structures on the observables. We extend the standard model hadronic current by additional right-handed vector as well as left- and…
We study nonleptonic decays of the orbitally excited, \su6 \rep{70}-plet baryons in order to test the hypothesis that the successes of the nonrelativistic quark model have a natural explanation in the large-$N_c$ limit of QCD. By working in…
A search for the D0 to \pi+ \pi- \mu+ \mu- decay, where the muon pair does not originate from a resonance, is performed using proton-proton collision data corresponding to an integrated luminosity of 1.0 fb-1 recorded by the LHCb experiment…
Simple dynamics, few available decay channels, and highly controlled radiative and loop corrections, make pion and muon decays a sensitive means of exploring details of the underlying symmetries. We review the current status of the rare…
Using the present upper bound on the neutron electric dipole moment, we give an estimate for the upper limit of the CP-violating couplings of the eta(eta') to the nucleon. Using this result, we then derive constraints on the CP-violating…
A new observation of D in a primordial gas cloud, made using the high resolution spectrograph at the Keck telescope, indicates an abundance $ D/H =(1.9-2.5) \times 10^{-4}$ \cite{SCHR}. Since deuterium is destroyed by stars, and the…
Using 1.8 million DDbar pairs and a neutrino reconstruction technique, we have studied the decays D^0 -> K^- e^+ nu_e, D^0 -> pi^- e^+ nu_e, D^+ -> Kbar^0 e^+ nu_e, and D^+ -> pi^0 e^+ nu_e. We find B(D^0 -> pi^- e^+ nu_e) = 0.299(11)(9)%,…
We present a new phenomenological analysis of the inclusive rare decay $B \to X_s \ell^+\ell^-$. In particular, we present the first calculation of the NNLL contributions due to the leading two-loop matrix elements, evaluated for arbitrary…
We have performed a detailed study of dilepton production from pp collisions including the subthreshold $\rho$ production via baryonic resonances (N(1520), N(1700)) in addition to the conventional dilepton sources as $\pi^0, \eta, \omega$…
We study in detail the prediction for the semileptonic decays $\bar{B} \to D (D^*) \pi \ell \bar{\nu}$ by heavy quark and chiral symmetry. The branching ratio for $\bar{B} \to D \pi \ell \bar{\nu}$ is quite significant, as big as…
Radiative corrections in the order ${\alpha\over{2\pi}}{{m^2_e}\over m^2_\mu}$ to $\mu $- and ${\alpha\over{2\pi}}{{m^2_\mu}\over m^2_\tau}$ to $\tau $- decays are calculated. The decay width is enhanced by $4.48\cdot 10^{-3}…
We report a measurement of the branching fractions for Bbar -> D(*)(pi)l-nubar decays based on 341.1 fb-1 of data collected at the Upsilon(4S) resonance with the babar detector at the PEP-II e+e- storage rings. Events are tagged by fully…
We report on baryon resonance production and decay in proton-proton collisions at a kinetic energy of $3.5$ GeV based on data measured with HADES. The exclusive channels $pp \rightarrow np\pi^{+}$ and $pp \rightarrow pp\pi^{0}$ as well as…
The semileptonic decays $\bar{B}\to D(D^*)\pi\ell\bar{\nu}$ are analyzed by heavy quark and chiral symmetries. The branching ratio is of order of a few percent for $\dpi$, but it is much smaller for $\dstar$, of order $10^{-4}-10^{-5}$. The…
Recent cosmological measurements favour additional relativistic energy density beyond the one provided by the three active neutrinos and photons of the Standard Model (SM). This is often referred to as "dark radiation", suggesting the need…
We construct the supersymmetric version of a model based on the gauge group SU(3)_c X SU(3)_L X U(1). We discuss the mechanism of baryon number violation which induces nucleon decay, and derive bounds on the relevant couplings.
The decays of non-strange positive parity excited baryons via emission of a pseudo-scalar meson are studied in the framework of the 1/Nc expansion to order 1/Nc. In particular, the pionic decays of the l=0 Roper baryons and of the l=2…
We present a search for the decay $B^{+} \to \tau^{+} \nu_{\tau}$ in $124.1 \times 10^{6}$ $\Upsilon(4S)$ decays recorded with the $BABAR$ detector at the SLAC PEP-II $B$-Factory. A sample of events with one reconstructed exclusive…
The baryon decay modes of B,bar{B}-> N_{1}bar{N}_{2}(f), bar{N}_{1}N_{2}(bar{f}) provide a frame work to test CP-invariance in baryon sector. It is shown that in the rest frame of B, N_{1} and bar{N}_{2} come out with longitudnal…