Project of upgrade of the DA NE accelerator

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

PRESENT AND NEXT FUTURE e+e- COLLIDERS LNF (Frascati) ADA ADONE DA NE 1960 -1962 1969 -1993 1998 -2009 DANAE: DAfne New - Adjustable Energy PHI-factory + Wide energy range High luminosity at PHI energy

DANAE Energy and Luminosity Range Energy @ center of mass (Ge. V) 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

PHYSICS PROSPECTS AT LNF WITH DANAE High Luminosity Program • K physics (http: //www. lnf. infn. it/kloe 2) • Ks rare decays • Neutral kaon interferometry • , ’ physics • Kaonic nuclear physics (http: //www. lnf. infn. it/esperimenti/siddharta/LOI_AMADEUS_March 2006. pdf) • Study of deeply bound kaonic nuclear states High Energy Program • Time-Like Form Factors (http: //www. lnf. infn. it/conference/nucleon 05/FF/) • Measurement of the nucleon and hyperons ( and ) form factors • Hadronic cross section measurement • Vector meson spectroscopy • Radiative decays of excited vector meson • physics (hep-ex/0603056)

DANTE: DAnae Nucleon Time-like form factor Experiment http: //www. lnf. infn. it/conference/nucleon 05/FF/ Letter of Intent by 82 physicist from 25 institution in 8 countries: http: //www. lnf. infn. it/conference/nucleon 05/loi_06. pdf Very positive feedback from the international community at the Workshop on Nucleon Form Factors, 12 -14 October 2005, Frascati

Hadron Electromagnetic Form Factors Rosenbluth • 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 polarization particle of spin S is defined by 2 S+1 form factors. Linear • FFs are closely connected with the generalized parton distribution (GPDs) deviation the new nonperturbative formalism which gives a complete description of from dipole the nucleon structure, and are used to constraint GPDs models. GE≠GM • Different charge • FFs are important ingredient in a wide range of experiments, from and neutrino magnetization distributions physics to many other measurements involving nucleons. • Quark angular momentum contribution? • Since the Stern experiment in 1932 indicating that the proton was not a point-like particle they have been extensively measured but: - In thespace-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 thetime-like region they are still pratically unknown Space-like FFs are real, time-like are complex and they are connected by dispersion relations

PROTON DATA |GM| Nucleon. Time-like FFs |GM| • Steep behaviour close threshold -4 • Early p. QCD scaling |GM| ~ Q • Time-like FF larger than space-like Assumption: |GE|=|GM | Assumption: GE=0 NEUTRON DATA Ebeam (Ge. V) neutron ~4 times the proton extrapolation p. QCD predicts the limit |G Mn|≈(q d/q u)2 |GMp|= | GMp|/4

Anomalous behavior in total cross section Ba. Bar found steps in total cross section at s =2. 2 and 2. 9 Ge. V

Nucleon Time-Like FFs measurements FF extraction from cross section measurements in e+e- N N and p p e+e s=4 M 2 |G M|=|GE| 2 s>>4 M |G M|>> E| |G • 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 |G M| can be more easily extracted, but it’s model-dependent |G E| remains unmeasured

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

Hyperon Form Factors Hyperon Energy th Decay ch L 2. 231 Np (pp- , np 0) S+ 2. 378 Np (pp 0 , np+) S 0 2. 385 Lg S- 2. 395 Np (np-) Smaller cross section as for nucleon production: s. TOT ~ 0. 1 nbarn • Y Y final state could be identified by detecting the decay of one hyperon • Angular distributions moduli of FF • For weakly decaying hyperons ( (1116), ±(1189)) the polarization measurement does not require a polarimeter (can be studied by looking at the angular distribution of the decay products)

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

Nucleon FF measurement: projected accuracy -1 Integrated luminosity 700 - 1000 pb (~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+cos 2 q)+Bsin 2 q neutron • 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+cos 2 q)+Bsin 2 q Statistical error of the order of few percent for all the 4 nucleon FFs in the whole explored region

Induced polarization The complex phases of the FFs in the TL region make it possible for a single outgoing baryon to be polarized in +e- BB even e 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)

Competitors VEPP 2000 32 • max energy ~ 1 Ge. V per beam, luminosity ~ 10 cm-2 s-1 • pp and nn measurement • start run ~ 2007 BEPC 33 • energy range ~ 2. 4 -4. 2 Ge. V, luminosity ~ 10 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 proton s (Ge. V) neutron MN 2. 0 2. 4 4. 2

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 (M 2 z) and Request: R ~1% in the whole energy range from threshold to DANAE impact on R Threshold region: 2 m - 0. 5 Ge. V 2 fb-1 @ 1 Ge. V (ISR events) stat < 1% peak region (0. 5 - 1 Ge. V) DA NE and VEPP 2 M 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 (M 2 z) 1 -2. 5 Ge. V energy region Is the most poorly known (~15% uncertanty) and contributes ~40% to (M 2 z) Significant improvement from DANAE

Other measurements made possible with DANAE @ high energy • The search and study of narrow vector mesons in the 1 -2. 4 Ge. V mass range Several evidences of narrow ( <100 Me. V), 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 Ba. Bar DM 2 e+ e- → 3 + 3 - Reaction M (Ge. V/c 2) (Me. V) DM 2 6 ~1. 93 ~ 35 FENICE mh ~1. 87 ~10 E 687 3 +3 - 1. 91± 0. 01 33± 13 Ba. Bar 3 +3 - 1. 88± 0. 05 130± 30 Ba. Bar 2 +2 -2 0 1. 86± 0. 02 160± 20 Ba. Bar 2 +2 - 1. 88± 0. 01 180± 20 Ba. Bar + -2 0 1. 89± 0. 02 190± 20 Experiment E 687 @ FNAL p → p 3 + 3 - M~ 2 m. N Discrepancy in • New vector meson? _ • NN bound state? (baryonium)

DANAE tentative schedule (C. Biscari - Workshop on DISCOVERIES IN FLAVOUR PHYSICS AT e+e- COLLIDERS, Frascati, February 28 2006) • To + 1 year • To + 2 years • To + 3 years • To + 4 years CDR and Project approval (2006) call for tender construction and delivery DA NE decommissioning and DANAE installation 1 st beam for commissioning and for 1 st experiment (2010)

Conclusions • A new project for ane+e- storage ring collider at the LNF (Italy)based on the actual DAFNE factory, is beendevelopping. • 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 Ge. V energy per beam) 33 • High luminosity (up to 10 cm-2 sec-1 @ ) For both cases interesting physics programs has been proposed • One of these is themeasurement 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 G and G E M • First measurement of Λ (Σ) baryon production (including polarization) strange baryon FF