1. Quark & Hadron Dynamics: AIACE
Physics goals:
Understand the nature of the strong interactions in
nucleons and nuclei in terms of fundamental constituents and QCD
Reasearch groups involved: INFN, Frascati and Genoa units & University of Genoa
total of 9 staff scientists/professors + 5 postdocs
Laboratory: Jefferson Lab (USA), Hall B (CLAS collaboration)
Beams: CW e-, g up to 6 GeV
Targets: LH2, LD2, He3, C, Fe, etc. + polarized NH3, ND3
Hardware contributions
LARGE ANGLE CALORIMETER
NEW START COUNTER
ELECTRONICS
NEW TAGGER ELECTRONICS
NEW FORWARD ANGLE
CHERENKOV
POLARIZED
NH3 /ND3 TARGET

2.  cosqK+ < 0.6, cosqp+ > 0.8 Parallel analysis in progress
AIACE physicists are involved in important collaboration committees (conferences, papers, etc.) + one PAC member from INFN
Journal publications may may 2003: 13 (5 with relevant italian contribution)
Talks at conferences may may 2003 : 13 (9 invited + 4 contributed)
Highlights from physics results
Possible evidence for pentaquark baryons in photoproduction off proton and nuclei
g p  K+ K - p+ (n)
in CLAS
angular cuts applied
 cosqK+ < 0.6, cosqp+ > 0.8
g p  K0 K+ (n)
in CLAS
angular cuts applied
 cosCM(K0) < -0.35
d  p K+ K - (n) in CLAS Q+
M(nK+) (GeV/c2)
VERY
PRELIMINARY
M(nK+) (GeV/c2)
Mass = 1523  5 MeV
FWHM ~ 9 MeV
Mass = 1573  5 MeV Q+
S. Stepanyan et al.
PRL 91, (2003)
TOPCITE = 100+
Are we observing
excited pentaquarks ?
Parallel analysis in progress
V. Koubarovsky et al.
PRL 92, (2004)
TOPCITE = 50+
 confirmatory run on proton under italian leadership to start this month

3. Surprising scaling properties observed analysing
Structure function moments, non-perturbative QCD and constituent quarks
Surprising scaling properties observed analysing
the higher moments of the F2 structure function
(sensitive to the valence region)
g1 proton polarized structure function
measured in very wide kinematic region
(resonances  DIS)
M. Osipenko et al.,
PRD 67, (2003)
R. Fatemi et al.,
PRL 91, (2003)
First calculated moment shows rapid change from DIS down to resonance region
New experiment under italian responsibility will probe spin response very close to photon point (new Cherenkov detector)
 connection with real photon GDH sum rule
 test of chiral perturbation theories
Recent interpretation in terms of a
constituent quark form factor
 possible evidence for extended objects
inside the proton from the dynamics
Petronzio, Simula, Ricco, PRD 67, (2003)