相关论文: The decay contribution to the parity-odd fragmenta…
We calculate the fragmentation function for a light quark to decay into a lepton pair to leading order in the QCD coupling constant. In the formal definition of the fragmentation function, a QED phase must be included in the eikonal factor…
We report measurements of direct CP-violating asymmetries in charmless decays of neutral bottom hadrons to pairs of charged hadrons with the upgraded Collider Detector at the Fermilab Tevatron. Using a data sample corresponding to 1 fb-1 of…
Precise measurements of the top quark decay properties at hadron colliders offer interesting new possibilities of testing the standard model. At the same time, recent intriguing experimental results concerning CP violation in the B_d and…
Precise lattice QCD results for hadronic matrix elements, decay constants and form factors play a crucial role in the determination of CKM matrix elements and in the identification of possible new physics contributions to flavour violating…
Background: Time-reversal-invariance violation, or equivalently CP violation, may explain the observed cosmological baryon asymmetry as well as signal physics beyond the Standard Model. In the decay of polarized neutrons, the triple…
On general grounds based on quantum field theory the decay amplitude for $\Sigma^0 \to \Lambda \gamma$ consists of a parity conserving magnetic and a parity violating electric dipole transition moment. Because of the subsequent…
Heavy quarks provide a new dimension to QCD, allowing tests of fundamental theory, the nature of color confinement, and the production of new exotic multiquark states. I also discuss novel explanations for several apparently anomalous…
Recently, LHCb experiment announced a 3.5$\sigma$ evidence for direct CP violation in $D^0$ decay by looking at the difference between $A_{CP}(D^0\rightarrow K^+K^-)$ and $A_{CP}(D^0\rightarrow \pi^+\pi^-)$. This is the first evidence of CP…
The recent development of perturbative QCD (PQCD) fragmentation functions has strong impact on quarkonium production. I shall summarize $B_c$ meson production based on these PQCD fragmentation functions, as well as, the highlights of some…
We report on some recent progress made in understanding weak matrix elements of mesons in the context of the next-to-leading order of the large-Nc approximation to QCD. Specifically, we first use the example of the weak contributions to the…
The fragmentation functions of $D^0$, $D^{\pm}$, $D_s^{\pm}$, $D^{*o}$, $D^{*\pm}$ and $\Lambda_c^{\pm}$ at $\sqrt{s}$$\simeq$10.6 GeV are measured with a data set of 102.7 fb$^{-1}$. Fragmentation model parametrizations (Peterson,…
Within the standard model, CP-violating asymmetries A(\Lambda^0_-) and A(\Xi^-_-) have been estimated in short-distance calculations to occur at the level of a few times 10^{-5}. We show here that in this model the dispersive contribution…
We consider weak decays of heavy hadrons (bottom and charmed) where the heavy quark acts as a spectator. Theses decays are heavily phase-space suppressed but may become experimentally accessible in the near future. These decays are…
We review the experimental methods to measure mixing and time-dependent $C\!P$ violation in $D^0$ decays into two hadrons. While these phenomena are usually neglected for $D^0 \to K^- \pi^+$ decays, this approximation is not always…
In this paper, we study CP violation in $\Lambda_c^+\to BP$ and $\Lambda_c^+\to BV$ decays, where $B,P$ and $V$ denote a light spin-1/2 baryon, pseudoscalar and a vector meson respectively. In these processes the $T$ odd CP violating…
We include strong parity-violating contributions to inclusive deep inelastic scattering (DIS) of longitudinally polarized leptons off an unpolarized target. At variance with standard results, we obtain nonvanishing parity-violating…
It follows on general grounds that the theta dependence in QCD is more complicated than suggested by the large N_c approach or instanton arguments. Generically, the vacuum energy E_{vac}(\theta) is a multi-valued function of \theta…
We analyze the so-called pinched weights, that are generally thought to reduce the violation of quark-hadron duality in Finite-Energy Sum Rules. After showing how this is not true in general, we explain how to address this question for the…
The existence of topological solutions and axial anomaly open a possibility of P and CP violation in QCD. For a reason that has not yet been established conclusively, this possibility is not realized in strong interactions - the…
We examine the interference \gamma Z box corrections to parity-violating elastic electron--proton scattering in the light of the recent observation of quark-hadron duality in parity-violating deep-inelastic scattering from the deuteron, and…