Transcript Document

On physical programme at FAIR
A. Sorin
5th Workshop on the scientific cooperation between German research centres and JINR
Dubna, 17-19 January 2005
Plan
1. The Scientific Programme at Facility for Antiproton and Ion Research (FAIR)
1.1
1.2
1.3
1.4
Nuclear Structure Physics (NUSTAR)
Physics with Antiprotons (PANDA)
Nuclear Matter Physics (CBM)
Antiproton-Proton Scattering Experiments with Polarization (PAX)
2. Scientific activity of BLTP
3. BLTP potential participation in the program at FAIR (SELECTED TOPICS)
3.1
3.2
3.3
Hadrons in dense medium
QCD phase diagram
Simulations of HIC
3.4
3.5
Nuclear structures and astrophysics
Spin physics
3.6
Manifestation of nonperturbative QCD vacuum in N-barN annihilation.
4. Conclusions
The Scientific Programme at Facility for
Antiproton and Ion Research (FAIR)
Nuclear structure physics (NUSTAR)
Physics with antiprotons
(PANDA, antiprotons of 1 – 15 GeV/c)
Nuclear Matter Physics (CBM, 10 – 40 GeV/nucl.)
1. Hadrons in dense medium (light vector mesons and charmonium )
2. QCD phase diagram (critical point, phases of strongly interacting matter)
Antiproton-Proton Scattering Experiments with Polarization (PAX)
Fields and Particles
 Development of the quantum field theory approach in the framework of the Standard Model of
fundamental interactions and its extensions.
 Lattice simulations for obtaining nonperturbative results in gauge theories.
 Elaboration of the multiloop calculations in QCD, Electroweak theory and Minimal
Supersymmetric Standard Model.
 Theoretical predictions concerning the experimental observation of supersymmetry, the Higgs
boson, investigation of the spin structure of the nucleon, T-odd spin effects, jet handedness, heavy
flavor physics, vacuum structure in QCD, hadron properties in dense and hot media.
 Elaboration of new phenomenological models to describe the hadron dynamics in the framework
of general principles of quantum field theory incorporating basic experimental patterns.
JINR-GERMAN COLLABORATION:
Berlin FUB HUB; Aachen RWTH; Bielefeld Univ.; Bochum – RUB; Bonn Univ.; Dortmund Univ. ;
Erlangen FAU; Hamburg DESY; Heidelberg Univ.; Jena FSU; Kaiserslautern TU; Regensburg
Univ.; Rostock Univ.; Mainz JGU; Munich LMU; Tubingen Univ.; Wuppertal Univ.; Zeuthen
DESY; Darmstadt GSI TUD
Nuclear Theory
 Properties of atomic nuclei at the limits of their stability.
 Dynamics of nuclear reactions and mechanisms of production of exotic nuclides.
 Fundamental properties of exotic few-body nuclear, atomic and molecular systems.
 Nuclear matter and its phase transitions at high temperature and density.
 Relativistic nuclear physics.
 Subnuclear and spin effects in few-nucleon systems.
JINR-GERMAN COLLABORATION:
Bonn Univ.; Erlangen FAU; Cologne Univ.; Leipzig Univ.; Regensburg Univ.; Rostock
Univ.; Siegen Univ.; Stuttgart Univ.; Frankfurt/Main GU; Giessen JLU; Mainz JGU;
Julich FZJ; Rossendorf FZR; Darmstadt GSI, TUD; Dresden MPI-PkS
Condensed Matter
 Multiparticle models of solids, electron-lattice and spin interactions, phase transitions and
kinetic phenomena in solids.
 Equilibrium and nonequilibrium media with strong correlations (liquids and nuclear matter),
the processes of multifragmentation, clusterization in phase transitions and the influence of
surface effects on properties of clusters.
 The theory of superconductivity, the influence of strong electric fields and temperature
gradients on elastic, magnetic, and thermal properties of granular superconductors.
 Nonlinear problems in multiparticle theory.
 Equilibrium systems of the statistical mechanics and dissipative systems far from the
thermodynamic equilibrium.
Mesoscopic systems and the Bose-Einstein condensation in atomic traps.
JINR-GERMAN COLLABORATION:
Bremen Univ.; Brunswick TU; Dortmund Univ.; Dresden TUD IFW; Duisburg Univ.;
Hamburg Univ.; Leipzig Univ.; Magdeburg OvGU; Rostock Univ.; Stuttgart MPI-FKF
Modern Mathematical Physics
 Quantum gravity, cosmology and strings
 Nonperturbative regimes of supersymmetric gauge theories.
 Quantum groups and integrable systems
JINR-GERMAN COLLABORATION:
Berlin FUB, HUB; Aachen RWTH; Bielefeld Univ.; Bonn UniBonn; Dortmund Univ.;
Hannover Univ.; Jena FSU; Leipzig Univ.; Munich MPI-P; Potsdam AEI
BLTP potential participation in the program at FAIR
SELECTED TOPICS:
 D-meson properties.
 J/ breakup.
 -meson in medium.
 QCD phase diagram
 Simulations of HIC.
 Search for the mixed phase.
 Spin physics and new parton distributions.
 Nonperturbative QCD vacuum in N-barN annihilation.
Unified approach for exploring the nonperturbative behaviour of the low-energy QCD
based on Dyson-Scwinger equations (DSE). Broad range of observables (hadron masses,
-scattering, electromagnetic form factors, heavy quark physics (leptonic, semileptonic, radiative
and strong decays of D and B mesons ) ) is described.
Calculated values of observables not
included in fitting the model parameters.
The quantities (GeV) used in fitting the parameters.
The weighting error is the experimental error.
M.A.Ivanov, Yu.L.Kalinovsky, C.D.Roberts, PR D60 (1999) 034018. Task for the theory: update.
Input: gluon Green function in the infrared region, solution of the DS and BS equations in the impulse
apptoximation  quark propagators (no-pole functions = quark confinement) + BS amplitudes.
Output: hadron masses, decay widths, form factors, cross sections, etc.
Tasks for PANDA: masses and decay widths of the charmonium orbital excitations, glueballs and
charmed hybrids. Leptonic and hadronic decays of the D-meson, search for CP-violation in the
nonleptonic D-decays. Tasks for CBM: the study of the D-meson behaviour in dense matter.
J/ dissociation in dense hadronic matter
Different approaches give very different results for the cross sections, 2 orders of magnitude(!) :
 nonrelativistic quark models (K.Martins, D.Blaschke, E.Quack PR C51 (1995) 2723,
 chiral Lagrangian (S.G.Matinyan, B.Mueller, PR C58 (1998) 2994 ).
Unified approach: relativistic quark model, effective relativistic Lagrangian describing
the nonlocal interaction of hadrons with their constituent quarks.
Input parameters: constituent
quark masses and scale hadron
size parameters.
Output quantities: form factors,
decay widths, cross sections, etc.
Box and D-exchange diagrams.
Ivanov, Korner, Santorelli, PRD70 (2004) 014005
Task to PANDA and CBM: measure the
spectral functions of J/ and D-mesons.
Task for theory: inclusion of light vector mesons.
Medium effects at chiral/deconfinement transition may explain anomalous J/
suppression (NA50, CERN)(G.Burau, D.B.Blaschke, Y.L.Kalinovsky PLB 506 (2001) 297).
Proposal for FAIR:
to consider the anomalous peak in the two-photon spectrum
as a signal of the mixed phase formation and, therefore, a
tool to identify the critical point in the QCD phase diagram
(D.B. Blaschke, A.N. Sissakian, A.S. Sorin, M.K. Suleymanov).
The number of anomalous two-photon events in the narrow invariant mass
region M_2gamma ~ M_sigma(mu_c, T_c) can be considered as a “clock” for
the duration of the mixed phase.
Problems of SPS and RHIC: huge background from neutral pion decays
complicates identification of this signal.
Privilege of FAIR: higher densities entail lower critical
temperatures  lower background!
A task for the theory: to check the robustness of the suggested signal by
evaluating the sigma2 gamma transition within nonperturbative QCD
approaches (lattice simulations, Dyson-Schwinger equations, Instanton calculus
etc.)
Simulations of Heavy-Ion Collisions (V.D.Toneev et al.)
Relativistic 3-fluid hydrodynamic model
for the energy range: a few to 200 A GeV .
New: time-delayed evolution of a third
baryon-free fluid, kinetic treatment of
interflow friction depending on scalar
density and in-medium cross sections
 nuclear stopping power.
Different equations of state can be used,
e.g. with a deconfinement phase
transition. Obtained results: for pure
hadronic equation of state (ideal gas of
hadrons and their resonances interacting
via a density-dependent mean-field).
Evolution of central Pb-Pb collisions in the phase diagram
Dynamical trajectories in the phase diagram show:
 E_0 > 10 A GeV: system enters the new phase;
 E_0 > 30 – 40 A GeV: system passes the critical point.
Future:
to include the phase transition in the simulation via the EoS;
to describe suggested signals for the phase transition:
 strangeness production n_s/n_pi;
 dilepton and photon production.
Search for the mixed phase of strongly interacting matter
Experimental results give an evidence of existence of sharp regime
changes in event characteristics as a function of the collision centrality.
The behaviour
changes at
ET  40-50 GeV
<Pt> of J/ and inverse slope ( T) of J/ transverse
mass distributions in Pb-Pb interactions at 158
GeV/nucl. as a function of centrality (ET ) (NA38,
NA50).
The cross section of J/ production in Pb-Pb
interactions at 158 GeV/nucl. as a function of
centrality (ET ) (NA38, NA50) normalaized to
the cross section of Drell-Yan pairs.
Possible explanation: the regime changes is a manifestation of the Mixed Phase (MP) formation
(A.N. Sissakian, A.S. Sorin, M.K. Suleymanov, G.M. Zinovjev).
The experimental information on conditions of MP formation is important to fix the onset stage of
the quark deconfiment for its future identification.
Search for MP: anomalous peak in the angular distribution of protons and anomalous angular
correlation of secondary particles production and anomaly in the small energy 0- or (+, -)-meson
(lepton) pairs production, simultaneously, as a function of the centrality.
Study of the missing ingredient of nucleon structure –TRANSVERSITY
The transversity is the number of transverse polarized quarks in transverse polarized nucleon.
Hadrons have to enter in PAIRS because the transversity is the chiral-odd distribution (unlike the
spin-averaged quark distribution and longitudinal spin-dependent quark distribution) .
Drell-Yan process: production of lepton pair with large mass Q and rapidity y
h + h --> l+ + l- + X via annihilation q + barq  l+ + l-.
For proton-proton collisions - small cross section d (the number of sea antiquarks is
small) and small asymmetry ATT proportional to the product of the transversities of
colliding hadrons (transversity of antiquarks is small):
it makes difficult to study the transversity in the polarized pp collisions at RHIC.
PAX: Drell-Yan process
with VALENCE
antiquarks(!) Advantage
is clearly seen:
Model approaches to transversity:
Probabilistic model
Chiral soliton model
(used for the prediction
of pentaquark):
Efremov, Goeke,
Schweitzer (Q2 =5 (solid),
9(dashed),16 (dotted) GeV2)
for Q2 =5GeV2:
interference effects at
quark level only
(solid) and also at the
level of quark-hadron
transition (dashed)
(Efremov, Teryaev,
Zavada)
Manifestation of nonperturbative QCD vacuum in N-barN annihilation.
Difference with the perturbative QCD
vacuum calculations: an enhancement
of flavour and spin dependence.
The problem of mesons spectroscopy:
are a0(980) and f0(980) excited q-barq or
exotic four quarks qq-barq-barq states?
a0(980) =
or
?
For proton-proton collisions - small cross section of four-quark mesons production (no valence
anti-quarks(!)): makes difficult to study in pp collisions at RHIC.
PANDA: the enhancement of four-quark mesons production because of VALENCE antiquarks(!)
Prediction in the framework of the
nonperturbative (one-instanton)
QCD vacuum calculation:
N.I.Kochelev, A.E.Dorokhov,
Yu.A.Zubov, Z.Phys. C65 (1995) 667.
Tasks for the theory:
1. calculations of perturbative QCD contributions in the framework of both
exotic and non-exotic quark models of a0(980) and f0(980) mesons;
2. to update the nonperturbative QCD calculations within the exotic and nonexotic quark models of a0(980) and f0(980) mesons.
Conclusions
Contributions of BLTP to FAIR:
1. Science in the different projects (PANDA, CBM, PAX and NUSTAR)
(BLTP is the member of CBM, PAX and NUSTAR collaborations).
2. Conferences and collaboration meetings, scientific exchange programmes
(e.g. Heisenberg-Landau programme) .
3. Educational programmes for young scientists (summer and Winter schools
programmes (DIAS-TH and Helmholtz International summer Schools,
University center).