24 research outputs found
Three-flavor chiral effective model with four baryonic multiplets within the mirror assignment
We study three-flavor octet baryons by using the so-called extended Linear
Sigma Model (eLSM). Within a quark-diquark picture, the requirement of a mirror
assignment naturally leads to the consideration of four spin-
baryon multiplets. A reduction of the Lagrangian to the two-flavor case leaves
four doublets of nucleonic states which mix to form the experimentally observed
states , , and . We determine the
parameters of the nucleonic part of the Lagrangian from a fit to masses and
decay properties of the aforementioned states. By tracing their masses when
chiral symmetry is restored, we conclude that the pairs , and
, form chiral partners.Comment: Based on the presentation given at FAIRNESS 2016, Workshop for young
scientists with research interests focused on physics at FAIR, 14-19 February
2016 Garmisch-Partenkirchen, Germany. 5 page
Angular distribution and azimuthal asymmetry for pentaquark production in proton-proton collisions
Angular distributions for production of the pentaquark are
calculated for the collisions of polarized protons with polarized target
protons. We compare calculations based on different assumptions concerning spin
and parity () of the state. For a wide class of
interactions the spin correlation parameters describing the asymmetric angular
distributions are calculated up to 250 MeV above production threshold. The
deviations from the near threshold behavior are investigated.Comment: 8 pages, 5 figure
Charmonium spectral functions in collision
We study the in-medium propagation of low-lying charmonium states: ,
(3686), and (3770) in a Au GeV collision. This energy
regime will be available for the PANDA experiment. The time evolution of the
spectral functions of the charmonium states is studied with a BUU type
transport model. We observe a substantial effect of the medium in the dilepton
spectrum.Comment: 6 pages, 4 figures, Presented at Excited QCD 2017, Sintra, Portuga
Phi meson production in near threshold proton-nucleus collisions
The cross section for production of Phi mesons in proton-nucleus reactions is
calculated as a function of the target mass. The decay width of the Phi meson
is affected by the change of the masses of the Phi, K+ and K- mesons in the
medium. A strong attractive K- potential leads to a measurable change of the
behavior of the cross section as a function of of the target mass. Comparison
between the kaon and electron decay modes are made.Comment: 4 pages, 1figure, new figure, new reference
Baryonic contributions to the dilepton spectrum of nucleon-nucleon collisions
We study the production of dileptons in relativistic nucleon-nucleon
collisions. Additionally to the traditional dilepton production channels
(vector meson decays, meson and Delta(1232) Dalitz decays) we included in our
model as new dilepton sources the Dalitz decay of higher unflavored baryon
resonances with spin<=5/2 and mass<=2.25 GeV/c^2. The contributions of these
new channels are estimated using experimental information about the Ngamma
decays of the resonances and have large uncertainties. The obtained dilepton
spectra are compared to the experimental data by the DLS collaboration.
Predictions for the HADES detector (SIS, GSI) are also discussed. In spite of
the large uncertainties of the higher resonance Dalitz decay contributions we
are able to draw the conclusion that these contributions are negligible
compared to the other dilepton sources and do not influence the detectability
of the phi and omega vector meson peaks.Comment: 9 pages, 4 figures, version accepted for publication in Phys. Rev.
Quarkyonic matter from hydro and rapid freeze out
Quarkyonic matter is a predicted phase between deconfined ideal QGP and Hadronic matter where the dominant degrees of freedom are quarks. Collective flow measurements indicate that the flow developed in QGP, as flow measurements scale with the constituent quark numbers. The possible reasons for the observed constituent quark number scaling were analyzed, arriving to the conclusion that collective flow must have frozen out early when quarks were the dominant constituents of matter.publishedVersio
Subthreshold phi-meson production in heavy-ion collisions
Within a transport code of BUU type the production of phi-mesons in the
reactions Ni+Ni at 1.93 AGeV and Ru+Ru at 1.69 AGeV is studied. New elementary
reaction channels rho+N(Delta) to phi+N and pi+N(1520) to phi+N are included.
In spite of a substantial increase of the \phi multiplicities by these channels
the results stay below the tentative numbers extracted from experimental data.Comment: 17 pages(LaTeX), two new figures adde
MesonNet 2013 International Workshop. Mini-proceedings
The mini-proceedings of the MesonNet 2013 International Workshop held in
Prague from June 17th to 19th, 2013, are presented. MesonNet is a research
network within EU HadronPhysics3 project (1/2012 -- 12/2014). The web page of
the conference, which contains all talks, can be found at
http://ipnp.mff.cuni.cz/mesonnet13Comment: 106 pages, 53 contributions. Mini-proceedings of the MesonNet 2013
International Workshop. Editors: K. Kampf, A. Kupsc, and P. Masjua