相关论文: Charm-quark fragmentation with an effective coupli…
In a coalescence plus fragmentation approach we calculate the heavy baryon/meson ratio and the $p_T$ spectra of charmed hadrons $D^{0}$, $D_{s}$ and $\Lambda_{c}^{+}$ in a wide range of transverse momentum from low $p_T$ up to about 10 GeV…
We review the hadro-production data presently available on open charm and beauty absolute production cross-sections, collected by experiments at CERN, DESY and Fermilab. The published charm production cross-section values are updated, in…
We have studied the effects of nonlinear scale evolution of the parton distribution functions to charm production in $pp$ collisions at center-of-mass energies of 5.5, 8.8 and 14 TeV. We find that the differential charm cross section can be…
The production of charm quarks is studied in deep-inelastic electron-photon scattering using data recorded by the OPAL detector at LEP at normal e+e- centre-of-mass energies from 183 to 209 GeV. The charm quarks have been identified by full…
Motivated by diquark exchange, we construct a class of extensions of the standard model. These models can generate large CP conserving and CP violating contributions to the doubly Cabbibo suppressed decays D^0\to K^+\pi^- without affecting…
We discuss production of charm quarks and mesons as well as nonphotonic electrons in $pp$ scattering at RHIC. The distributions in rapidity and transverse momentum of charm and bottom quarks/antiquarks are calculated in the…
We present an analysis of the role of the running coupling constant at the intersection of perturbative and nonperturbative QCD. Although the approaches that have been considered so far in these two regimes appear to be complementary to…
Effective interaction models of quantum chromodynamics, based on quark degrees of freedom, have been successfully employed to compute the properties of a large array of ground and excited meson and baryon states, along with their…
Recently a lot of new experimental results on open charm hadrons have appeared. In particular many D meson resonances have been discovered. We discuss strong decays of positive and negative parity charmed mesons within heavy meson chiral…
We report on our first set of results for charm physics, using a mixed-action setup with maximally twisted valence fermions on CLS $N_f=2+1$ ensembles. This setup avoids the need of improvement coefficients to subtract $O(am_c)$ effects.…
Recent measurements of charm-baryon production at midrapidity by the ALICE collaboration show baryon-to-meson yield ratios significantly higher than those measured in $\rm e^+e^-$ collisions, suggesting that the charm fragmentations are not…
Recent experimental results on the Lambda_c/D^0 ratio in proton-proton collisions have revealed a significant enhancement compared to expectations based on universal fragmentation fractions/functions across different colliding systems, from…
By combining experimentally measured partial branching fractions for the semileptonic decays D to K l nu and D to pi l nu with lattice calculations of the form factors f_+^{D to K}(q^2) and f_+^{D to pi}(q^2), one can extract the CKM matrix…
We present the first results of numerical simulations of a 2+1 dimensional fermion field theory based on a recent proposal for a model of graphene, consisting of N_f four-component Dirac fermions moving in the plane and interacting via an…
In this work, we investigate the heavy-flavor conserving weak decays of charmed baryons, specifically the processes $\Xi_{c} \to \Lambda_{c} \pi$ and $\Omega_{c} \to \Xi_{c} \pi$, where the pole model is employed to account for the…
Decoupling of heavy quarks at low energies can be described by means of an effective theory as shown by S. Weinberg in Ref. [1]. We study the decoupling of the charm quark by lattice simulations. We simulate a model, QCD with two degenerate…
In this talk, I present new results from CLEO on charm and bottom hadrons. Most of the talk will be on the issue of the B semileptonic branching fraction, its connection to the number of charm quarks produced in the decay of a b quark, and…
Total charm-pair cross sections in $pp$ collisions are interesting because they can be calculated to NNLO in QCD without any reference to fragmentation effects. On the other hand, the fiducial differential charm cross sections from which…
We discuss the production of charmonium and open charm in nuclear collisions at SPS/FAIR energies within the framework of the statistical hadronization model. The increasing importance at lower energies of Lambda_c production is discussed…
We discuss the production via fragmentation of excited heavy mesons and baryons, and their subsequent decay. In particular, we consider the question of whether a net polarization of the initial heavy quark may be detected, either in a…