2,527 research outputs found
Exploring QCD dynamics in medium energy semiexclusive collisions
We demonstrate that studies of the semiexclusive large angle photon - nucleus
reactions: with tagged photon beams of
energies GeV which can be performed in Hall D at Thomas Jefferson
National Acceleration Facility (TJNAF) would allow to probe several aspects of
the QCD dynamics: establish the -range in which transition from soft to hard
dynamics occurs, compare the strength of the interaction of various mesons and
baryons with nucleons at the energies of few GeV, as well as look for the color
transparency effects.Comment: 13 pages, 6 figures, minor revisions, version accepted in Phys. Lett.
Rescattering effects in antiproton-induced exclusive and production on the deuteron
On the basis of the generalized eikonal approximation we study the exclusive
reactions and in
vicinity of the thresholds for charmonium production on a free proton target.
It is shown that the rescattering of the incoming antiproton and outgoing
charmonium on the spectator neutron leads to a depletion of the charmonium
production at low- and to an enhancement at high transverse momenta. This is in
qualitative agreement with previous studies of hard proton knockout in
proton-deuteron collisions. We analyze different physical sources of
uncertainty which may influence the extraction of the total charmonium-neutron
cross section. The color transparency effect for the incoming largely
compensates the influence of charmonium rescattering both at low and high
transverse momenta. Different choices of the deuteron wave function lead to
significant uncertainties at high transverse momenta. As an outcome of the
calculations of charmonium production, we also provide predictions on the
production of open charm hadrons due to the dissociation of the charmonium on
the neutron. It is shown that the open charm production cross section is
proportional to the total charmonium-nucleon cross section and quite stable
with respect to the variation of other parameters of the model. We thus suggest
that open charm channels are most suited for future studies of
charmonium-nucleon interactions at PANDA with a deuteron target.Comment: 28 pages, 8 figures, modified sec. 1 and 2, new Fig. 2, added
references, results unchanged, version accepted in EPJ
Kaon production from 1 to 40 A GeV
Kaon production is studied within the Giessen Boltzmann-Uehling-Uhlenbeck
(GiBUU) model. Results are compared with experiment and with other models. The
influence of the kaon potential on the kaon azimuthal distributions at SIS
energies is considered. We also discuss the role of the many-body collisions at
high-density phase of reaction.Comment: 6 pages, 4 figures, Proc. of the Int. Workshop on Hot and Dense
Matter in Relativistic Heavy Ion Collisions, 09-12.04.2006, Budapes
Determination of the structure of the in collisions
Currently, the structure of the meson is unknown. Different
competing models of the exotic state exist, including the
possibilities that this state is either a mesonic molecule with dominating composition, a tetraquark, or a -gluon hybrid state. It is expected that the state is rather
strongly coupled to the channel and, therefore, can be produced in
and collisions at PANDA. We propose to test the
hypothetical molecular structure of by studying the or stripping reactions on a nuclear residue.Comment: 19 pages, 8 figures; version accepted in PL
Kaon production from 1 to 40 A GeV
Kaon production is studied within the Giessen Boltzmann-Uehling-Uhlenbeck
(GiBUU) model. Results are compared with experiment and with other models. The
influence of the kaon potential on the kaon azimuthal distributions at SIS
energies is considered. We also discuss the role of the many-body collisions at
high-density phase of reaction.Comment: 6 pages, 4 figures, Proc. of the Int. Workshop on Hot and Dense
Matter in Relativistic Heavy Ion Collisions, 09-12.04.2006, Budapes
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