1. Project of upgrade of the DANE accelerator and the associated programme
Patrizia Rossi - INFN-Laboratori Nazionali di Frascati (ITALY)
JINR Programme Advisory Committee for Particle Physics
25th meeting, Dubna 20 April 2006

2. PRESENT AND NEXT FUTURE e+e- COLLIDERS
ADA
ADONE
DANE
LNF (Frascati)
DANAE: DAfne New - Adjustable Energy
PHI-factory + Wide energy range
High luminosity at PHI energy

3. DANAE Energy and Luminosity Range
center of mass (GeV)
1.02
2.4
Integrated luminosity per year (fb-1) > 10 1
Total integrated luminosity (fb-1) > 50 3
Peak luminosity (cm-2 sec-1) >
1033
1032
Use of DANE builbings
Use of DANE infrastructures
Use of DANE injection system + upgrade of transfer lines
Use of large part of magnets, diagnostics
NEW
Dipoles
Wigglers
RF system
Vaccum chamber
Interaction region
Application of new technologies
Use of DANE runs for R&D while increasing L for next experiments

4. High Luminosity Program
PHYSICS PROSPECTS AT LNF WITH DANAE
High Luminosity Program
K physics (
Ks rare decays
Neutral kaon interferometry
, ’ physics
Kaonic nuclear physics (
Study of deeply bound kaonic nuclear states
High Energy Program
Time-Like Form Factors (
Measurement of the nucleon and hyperons ( and ) form factors
Hadronic cross section measurement
Vector meson spectroscopy
Radiative decays of excited vector meson (hep-ex/ )
 physics

5. DANTE: DAnae Nucleon Time-like form factor Experiment
Letter of Intent by 82 physicist from 25 institution in 8 countries:
Very positive feedback from the international community at the
Workshop on Nucleon Form Factors, October 2005, Frascati

6. Hadron Electromagnetic Form Factors
Different charge and magnetization distributions
Quark angular momentum contribution?
Rosenbluth
polarization
Linear
deviation
from dipole
GE≠GM
Hadron Electromagnetic Form Factors
FFs are fundamental quantities describing the internal structure of the hadron (# point-like). In a P- and T-invariant theory, the EM structure of a particle of spin S is defined by 2S+1 form factors.
FFs are closely connected with the generalized parton distribution (GPDs) the new non-perturbative formalism which gives a complete description of the nucleon structure, and are used to constraint GPDs models.
FFs are important ingredient in a wide range of experiments, from neutrino physics to many other measurements involving nucleons.
Since the Stern experiment in 1932 indicating that the proton was not a point-like particle they have been extensively measured but:
- In the space-like region recent results obtained with polarized beam completely changed our knowledge showing a dramatically different picture. The charge and magnetization distribution inside the nucleon are different
- In the time-like region they are still pratically unknown
Space-like FFs are real, time-like are complex and they are connected by dispersion relations

7. NucleonTime-like FFs |GM| PROTON DATA |GM| NEUTRON DATA
Early pQCD scaling |GM| ~ Q-4
NucleonTime-like FFs
|GM|
Assumption: |GE|=|GM |
Ebeam (GeV)
PROTON DATA
Steep behaviour close threshold
Time-like FF larger than space-like
|GM|
Assumption: GE=0
NEUTRON DATA
neutron ~4 times the proton
extrapolation
pQCD predicts the limit
|GMn|≈(qd/qu)2 |GMp|= | GMp|/4

8. Anomalous behavior in total cross section
BaBar found steps in total cross section at s =2.2 and 2.9 GeV

9. Nucleon Time-Like FFs measurements
FF extraction from cross section measurements in
e+e- N N and p p  e+e-
s=4M2  |GM|=|GE| s>>4M2  |GM|>>|GE|
Up to now, no independent extraction of both TL FFs has been performed
FF measurements are based on total cross section, under some theoretical assumption on their ratio
|GM| can be more easily extracted, but it’s model-dependent
|GE| remains unmeasured

10. Summaryzing:Nucleon Time-like FFS are basically unknown
|GE|  |GM| in the space-like region (recent Jlab results). Why should be valid in the time-like region?
|GEp|/|GMp|
Ebeam (GeV)
DANAE
Phases of time-like FFs never measured
Only one measurement for neutron magnetic FF
Inconsistencies between data and pQCD expectations

11. Smaller cross section as for nucleon production: sTOT ~ 0.1 nbarn
Hyperon Form Factors
Smaller cross section as for nucleon
production: sTOT ~ 0.1 nbarn
Hyperon
Energy th
Decay ch L
2.231
Np (pp- , np0) S+
2.378
Np (pp0 , np+) S0
2.385 Lg S-
2.395
Np (np-)
Y Y final state could be identified by detecting the decay of one hyperon
Angular distributions  moduli of FF
For weakly decaying hyperons (L(1116), S±(1189)) the polarization measurement does not require a polarimeter (can be studied by looking at the angular distribution of the decay products)

12. DETECTOR REQUIREMENTS
The DANE detectors
KLOE
FINUDA
1 m
DETECTOR REQUIREMENTS
high detection acceptance for charged and neutral particles
good neutron detection efficiency
polarimeter

13. Nucleon FF measurement: projected accuracy
Integrated luminosity  pb-1 (~6 months measurements)
proton
Projected data assuming
|GE| = |GM| or |GE|/|GM| from DR
Integrated luminosity =100 pb-1
Constant detection efficiency =80%
fit of angular distributions in
the FINUDA coverage
F(q)=A(1+cos2q)+Bsin2q
neutron
Statistical error of the order of few percent for all the 4 nucleon FFs in the whole explored region
Projected data assuming
|GE| = |GM| or |GE|=0
Integrated luminosity =100 pb-1
Constant detection efficiency =15%
fit of angular distributions in
the FINUDA coverage
F(q)=A(1+cos2q)+Bsin2q

14. Induced polarization - extraction of FF relative phase
The complex phases of the FFs in the TL region make it possible for a single outgoing baryon to be polarized in
e+e-BB even without polarization in the initial state -
extraction of FF relative phase
non negligible polarization
Py maximal at 45° and 135°
high discriminating power between theories
For ΔP/P 30 %: ~ 1 year measurement (total luminosity 2500 pb-1 )

15. Competitors VEPP2000 BEPC PANDA-PAX
s (GeV) MN
2.0
2.4
4.2
proton
neutron
VEPP2000
max energy ~ 1 GeV per beam, luminosity ~ 1032 cm-2 s-1
pp and nn measurement
start run ~ 2007
BEPC
energy range ~ GeV, luminosity ~ 1033 cm-2 s-1
only pp measurement
start run ~ 2007
PANDA-PAX
inverse reaction pp → e+e- (no neutron measurement)
single and double polarization measurements
start run >2013
DANAE

16. Other measurements made possible with DANAE @ high energy
Study of angular asymmetry in pp (nn) distributions
 look for 2-photon contribution
Precision test of the SM: Measurement of the total cross section e+ e- →hadrons to get the hadronic contribution to (M2z) and 
DANAE impact on R
1-2.5 GeV energy region
Is the most poorly known (~15% uncertanty)
and contributes ~40% to (M2z)
Significant improvement from DANAE
Threshold region: 2m GeV
2 1 GeV (ISR events) stat < 1%
 peak region ( GeV)
DANE and VEPP2M have measured the hadronic total cross section at a percent level (even if there are discrepancies at about ±5% level). Babar is going to release its results
No significant improvement from DANAE
Request: R ~1% in the whole energy range from threshold to 
(M2z) 

17. Other measurements made possible with DANAE @ high energy
The search and study of narrow vector mesons in the GeV mass range
Several evidences of narrow (<100 MeV), unespected structures like for istance in
e+ e- →3+3 - , e+ e- →2+2 - 20 , e+ e- →+ - 20 , e+ e- →2+2-
and the corresponding channels in diffractive photoproduction, near the NNbar threshold
e+ e- → 3p+ 3p-
DM2
FNAL
g p → p 3p+ 3p-
BaBar
New vector meson?
NN bound state? (baryonium)
M~ 2mN
Discrepancy in  _
Experiment
Reaction
M (GeV/c2)
G (MeV)
DM2 6
~1.93
~ 35
FENICE mh
~1.87
~10
E687
3+3-
1.91±0.01
33± 13
BaBar
1.88±0.05
130± 30
2+2-20
1.86±0.02
160± 20
2+2-
1.88±0.01
180± 20
+-20
1.89±0.02
190± 20

18. DANAE tentative schedule (C
DANAE tentative schedule (C. Biscari - Workshop on DISCOVERIES IN FLAVOUR PHYSICS AT e+e- COLLIDERS, Frascati, February )
To CDR and Project approval (2006)
To + 1 year call for tender
To + 2 years construction and delivery
To + 3 years DANE decommissioning and
DANAE installation
To + 4 years 1st beam for commissioning and
for 1st experiment (2010)

19. Conclusions
A new project for an e+e- storage ring collider at the LNF (Italy) based on the actual DAFNE  factory, is been developping.
The new machine will be amplified in energy and luminosity and it is designed to run in two modes:
High energy (up to 1.2 GeV energy per beam)
High luminosity (up to 1033 cm-2 )
For both cases interesting physics programs has been proposed
One of these is the measurement of the time-like nucleon and hyperon form factors -
The proposed experiment will allow:
Accurate measurement of pp and nn cross section
 model-independent extraction of proton and neutron FFs
at the few percent level for the proton and < 10% for the neutron.
First measurement of outgoing proton (neutron) polarization
 relative phase between GE and GM
First measurement of Λ (Σ) baryon production (including polarization)
 strange baryon FF