Electromagnetic
Probes of Hot and Dense Matter
ECT* Programme, Trento, June 3-11, 2005
Organizers: Peter Braun-Munzinger, Charles Gale
and Ralf Rapp (coordinator)
Scope of the Meeting:
Due to their penetrating character,
electromagnetic (e.m.) observables (photons and lepton pairs) are unique
and
powerful probes of the high-energy density matter
created in high-energy collisions of heavy nuclei.
On the one hand, photons and dileptons of
invariant masses and/or transverse momenta above about 1 GeV are
believed to reveal the temperatures achieved in
the highly excited nuclear systems, and thus, in turn, test the degree
of thermalization in the early phases of the
reaction. On the other hand, low-mass dileptons directly probe possible
in-medium modifications of the light vector mesons
(rho, omega and phi), and therefore allow to address the question
of hadronic mass generation in connection with the
restoration of chiral symmetry in the QCD phase transition(s).
The above issues have been intensively studied
theoretically, stimulated by tantalizing experimental results obtained
by the first generation of experiments during the
1990's. At the BEVALAC and the SPS substantial excess radiation
over expected sources has been observed at masses
and transverse momenta from 0 to 3GeV. However, as of now,
the theoretical interpretations remain
inconclusive. The enhancement below the free rho-mass is equally
well described
by a broadening or (and) a reduced mass of the
vector spectral functions, whereas thermal radiation at higher mass
could not be unambiguously discerned from
primordial sources (i.e. open-charm decays and nuclear modifications of
perturbative QCD processes). This situation
is expected to dramatically improve owing to a considerable influx of
new experimental results by the time of the
meeting, including data at SIS energies from HADES, at SPS energies
from CERES and NA60, as well as at RHIC energies
from PHENIX and STAR.
This workshop is intended to gather about 40 of
the world-leading experimental and theoretical experts to perform
an in-depth exchange, analysis and discussion of,
and make progress in, our understanding of electromagnetic probes
of hot and dense nuclear matter.
Topics include:
- Low-Mass Dileptons, Light Vector Mesons in Medium and
Chiral Symmetry Restoration
- Thermal Photons
- Intermediate-Mass Dileptons and non-/perturbative QGP
Emission
- E.M. Emission from Color-Glass-Condensate, Pre-Equilibrium
and correlated open-charm decays
- Future Perspectives
Workshop
Information: