334 research outputs found
Charmed Hadrons from Strangeness-rich QGP
The yields of charmed hadrons emitted by strangeness rich QGP are evaluated
within chemical non-equilibrium statistical hadronization model, conserving
strangeness, charm, and entropy yields at hadronization.Comment: 6 pages, 2 figures SQM 2006; the same as J. Phys. G in pres
Heavy Flavor Probes of Quark Matter
A brief survey of the role of heavy flavors as a probe of the state of matter
produced by high energy heavy ion collisions is presented. Specific examples
include energy loss, initial state gluon saturation, thermalization and flow.
The formation of quarkonium bound states from interactions in which multiple
heavy quark-antiquark pairs are initially produced is examined in general.
Results from statistical hadronization and kinetic models are summarized. New
predictions from the kinetic model for J/Psi at RHIC are presented.Comment: Based on invited plenary talk at Strange Quark Matter 2004, Cape
Town, South Africa, September 15-20, 2004, references completed, published in
J. Phys. G: Nucl. Part. Phys. 31 (2005) S641-S64
Quarkonium Formation Time in a Model-Independent Approach
We use dispersion relations to reconstruct, in a model-independent way, the
formation dynamics of heavy quarkonium from the experimental data on e+ e-
annihilation to Q-bar Q. We extract a distribution of formation times with a
mean value for the J/psi, tau{J/psi} = 0.44 fm; and for the Upsilon,
tau{Upsilon} = 0.32 fm. The corresponding widths of these distributions are
given by Delta-tau{J/psi} = 0.31 fm and Delta-tau{Upsilon} = 0.28 fm. This
information can be used as an input in modeling of heavy quarkonium production
on nuclear targets.Comment: 10 pages with 3 figure
B_c Meson Production in Nuclear Collisions at RHIC
We study quantitatively the formation and evolution of B_c bound states in a
space-time domain of deconfined quarks and gluons (quark-gluon plasma, QGP). At
the Relativistic Heavy Ion Collider (RHIC) one expects for the first time that
typical central collisions will result in multiple pairs of heavy (in this case
charmed) quarks. This provides a new mechanism for the formation of heavy
quarkonia which depends on the properties of the deconfined region. We find
typical enhancements of about 500 fold for the B_c production yields over
expectations from the elementary coherent hadronic B_c-meson production
scenario. The final population of bound states may serve as a probe of the
plasma phase parameters.Comment: 9 Pages, 11 Postscript Figure
Kaon Weak Decays in Chiral Theories
The ten nonleptonic weak decays , , , , , are predicted for a
chiral pole model based on the linear sigma model theory which automatically
satisfies the partial conservation of axial current (PCAC) hypothesis. These
predictions, agreeing with data to the 5% level and containing no or at most
one free parameter, are compared with the results of chiral perturbation theory
(ChPT). The latter ChPT approach to one-loop level is known to contain at least
four free parameters and then predicts a rate
which is 60% shy of the experimental value. This suggests that ChPT is an
unsatisfactory approach towards predicting kaon weak decays.Comment: 12 pages, 8 eps figure
Inelastic Final-State Interactions and Two-body Hadronic B decays into Single-Isospin channels
The role of inelastic final-state interactions in CP asymmetries and
branching ratios is investigated in certain chosen single isospin two-body
hadronic B decays. Treating final-state interactions through Pomeron and Regge
exchanges, we demonstrate that inelastic final state interactions could lead to
sizeable effects on the CP asymmetry.Comment: 23 pages, Latex, 1 eps-figur
Radiative decays of heavy and light mesons in a quark triangle approach
The radiative meson decays and are
analyzed using the quark triangle diagram. Experimental data yield well
determined estimates of the universal quark-antiquark-meson couplings
and for the light meson sector. Also
predictions for the ratios of neutral to charged heavy meson decay coupling
constants are given and await experimental confirmation.Comment: 31 pages of RevTex, 5 figures, Postscript version available at
http://info.utas.edu.au/docs/physics/theory/Publications/9548.html, scheduled
to appear in Phys. Rev. D, vol 53, issue 11, 199
Hard probes in heavy ion collisions at the LHC: heavy flavour physics
We present the results from the heavy quarks and quarkonia working group.
This report gives benchmark heavy quark and quarkonium cross sections for
and collisions at the LHC against which the rates can be compared in
the study of the quark-gluon plasma. We also provide an assessment of the
theoretical uncertainties in these benchmarks. We then discuss some of the cold
matter effects on quarkonia production, including nuclear absorption,
scattering by produced hadrons, and energy loss in the medium. Hot matter
effects that could reduce the observed quarkonium rates such as color screening
and thermal activation are then discussed. Possible quarkonium enhancement
through coalescence of uncorrelated heavy quarks and antiquarks is also
described. Finally, we discuss the capabilities of the LHC detectors to measure
heavy quarks and quarkonia as well as the Monte Carlo generators used in the
data analysis.Comment: 126 pages Latex; 96 figures included. Subgroup report, to appear in
the CERN Yellow Book of the workshop: Hard Probes in Heavy Ion Collisions at
the LHC. See also http://a.home.cern.ch/f/frixione/www/hvq.html for a version
with better quality for a few plot
- …