The NuTeV Experiment at Fermilab used a sign-selected beam to generate either neutrinos or anti-neutrinos with a wrong-sign background contamination of 10$^{-3}$. During the 1996-97 run NuTeV recorded over a million charged current events. The charm sea may be measured using events in which the wrong sign of muon is detected. The high purity and statistics of this experiment also allows us to extract the strange sea parameters from opposite sign dimuon events.

Direct CP violation beyond the standard model can be produced in charged D decays to final states with a $K_S$ by small new physics contributions to the transitions $D^+ \rightarrow K^0 X^+$, where $X^+$ denotes any positively charged hadronic state or transitions $D^+ \rightarrow K^0 \bar K^0 K^{(*)+}$, where $K^{(*)+}$ denotes any positive strange state. These transitions are doubly-Cabibbo suppressed and color suppresed in the standard model and branching ratios are experimentally observed to be suppressed by two orders of magnitude relative to the allowed $D^+ \rightarrow \bar K^0 X^+$ or $D^+ \rightarrow \bar K^0 \bar K^0 K^{(*)+}$, branching ratio. An even smaller new physics contribution might produce an observable CP asymmetry in $D^\pm \rightarrow K_S X^\pm$ or $D^{\pm} \rightarrow K_S K_S K^{(*)\pm}$ decays. Since such asymmetries are easily checked in the early stages of any charm production experiment, it seems worth while to check them before the opportunity is lost in later stages of the analysis, even if no theoretical model predicts such an asymmetry.

In charged current deep inelastic scattering charm is dominantly produced in scattering events on strange quarks, thereby allowing for an experimental determination of the nucleon's strange sea density. A measurement of the energy spectrum of final state charm fragments (D-mesons) determines the charm fragmentation function at spacelike scales considerably below typical e^+e^- c.m.s. energies. We have calculated NLO corrections to the naive s->c parton model production picture. The latter stem from W^*g->cbar{s} boson gluon fusion, W^*s->cg real gluon emission and from virtual corrections to s->c. They are numerically important and well understood.

Recent discovery of B_c meson by CDF collaboration and proposed new experiments at FNAL and CERN call for extensive theoretical studies of B_c mesons. Here we investigate the possibility of measuring B_c decay constant in radiative leptonic decays within the framework of an effective field theory formulated for non-relativistic quarks, the NRQCD. We calculate the width and the photon energy spectrum and comment on the role of excited vector B_c states.

The E791 experiment used a 500 GeV pion beam on a nuclear target at the Tagged Photon Laboratory (Fermilab) to investigate the physics of charm production and decay. During six months of running in 1991, the E791 experiment wrote 20 billion events to tape. Recent results from this data sample are presented. These results include limits on D0-D0bar mixing and CP violation, semileptonic form factor and branching ratio measurements and hadronic decay substructure analyses.

We discuss the double spin asymmetries in charmonium states hadroproduction with non-zero transverse momenta at fixed target energies, $\sqrt{s}\simeq40$ GeV, within the framework of the factorization approach. It is shown that observation of oppsite sign double spin asymmetries will allow to distinguish between Nonrelativistic QCD (NRQCD) factorization approach and color evaporation model (CEM), two different mechanisms of heavy quarkonium production.

The production of $\Upsilon$ mesons at fixed target energies is considered. It is shown that Nonrelativistic QCD (NRQCD) predicts $\Upsilon$ production at fixed target energies with sizeable transverse polarization. The posibility of observation of $\Upsilon$ polarization at HERA-B experiment are considered.

FOCUS is a high statistics Charm experiment located in the Fermilab Wide Band Photon Beam. It is an upgrade of the E687 spectrometer and during the 1996-1997 Fermilab Fixed Target run, the FOCUS collaboration collected over 15 times the Charm statistics of E687 and in particular will have over 25 times the statistics of E687 in semileptonic Charm decays. This means FOCUS should achieve its goal of 1 million fully reconstructed Charm decays. The status of the reconstruction and analyses will be presented. The event reconstruction of the 6.5 billion events is over 95% complete. Physics skims/stripping is in progress.

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URL: http://www.fnal.gov/projects/hq98/html/poster_abs.html
title: HQ98 Poster Session Abstracts