INFN RoadMap Working Group F.Ambrosino, F.Anulli, D.Babusci, S.Bianco, C.Bini, N.Brambilla, R.DeSangro, P.Gauzzi, P.M.Gensini, S.Giovannella, V.Muccifora, M.Negrini, F.Nguyen, S.Pacetti, G.Pancheri, M.Passera, A.Passeri, A.D.Polosa, M.Radici, Y.N.Srivastava, A.Vairo, G.Venanzoni, G.Violini Cosenza,Ferrara,Frascati,Milano,Napoli,Padova,Pavia,Perugia,Roma1,Roma3 arXiv:hep-ex/ LNF 06/11 (IR) Prospects for e + e - physics at LNF from  to  L.N.F. 31/05/06

Energy (cm) (GeV)1.02<2.5 Peak luminosity (cm -1 sec -2 )8 × Total integrated luminosity (fb -1 )~ The physics case for DANAE (DAFNE-2)  Physics at a high luminosity  – factory (non K-decays and non hypernuclei)  e + e - physics in the energy range 1 < √s < 2.5 GeV 3. An higher energy option: the  – charm factory 2. Detector considerations 4. Final remarks Outline

(1)Measurement of [ e + e -  hadrons ] cross-section in the range 2M  < √s < 2.5 GeV.  hadronic contributions to g-2  hadronic contributions to  em running  vector meson spectroscopy (2) Radiative decays of vector mesons  ,  ’ physics (from the  )  physics of scalar mesons (multiquark states) (3)  physics       ,     from threshold up to ~1GeV: the    widths of scalar and pseudoscalar mesons (  0, ,  ’, f 0 (980), a 0 (980)) (4) Hadron form-factors in the time-like region  proton, neutron, ,  (5) Systematic of K – N interactions 1. The physics case for DANAE (DAFNE-2) Mostly hadron physics + precision tests of the SM

Status of R had measurements   s < 1 GeV: accessible through radiative return; work in progress by KLOE;  1 <  s < 2.5 GeV: accessible with energy scan.

  s < 1 GeV: dominant for g-2. Best measurements: KLOE (rad.ret.) CMD-2 / SND e + e - energy scan. ~agreement between rad.ret. and e + e - data   R/R ~ 1% disagreement with  data (but the situation is in progress) Comparison between:  – data ( yellow band ) KLOE rad.ret. data ( black ) e + e - scan data ( colors ) a  = (g-2)/2 a  exp -a  th ~ 2  3 st.dev. (e + e - ) ~ 1 st.dev. (  )

 1 <  s < 2.5 GeV: dominant for  em. Old experiments with large systematic uncertainties + B-factories (rad.ret.) Inclusive vs. Exclusive measurements Impact of DANAE scan: Statistical errors only (same binning)  (%) BABAR present (blue) BABAR final (green) DANAE 1 year (red)

Summary: Precision Tests of the Standard Model a  = (g-2)/2: ( ) Present situation:  (a  ) exp = 60 [  25 ( BNL E969, …? ) ]  (a  ) th = (60  90)HLO [based on  R/R ~ 1% (  s<1 GeV)]  (25  40)LBL [purely theory] Marginal improvement can be foreseen for g-2  had : (10 -5 ) Present situation:  (  had ) = 35   (sin 2  eff lept )=12.5  R/R ~ 1% (  s<M(J    (  had ) = 7   (sin 2  eff lept )=2.5 Very important improvement for  em Energy scan is very important. Competitors: B-factories and  – charm factories (rad.ret.) Novosibirsk:  s < 2 GeV L < cm -2 s -1 from 2007

An alternative measurement of running  QED (thanks to L.Trentadue) through Small Angle Bhabha extending the LEP analysis at lower q 2. t = -1/2s(1-cos  )

Energy scan  Vector (and Scalar) Meson Spectroscopy Several new “questions” after Babar rad.ret. data:   and  recurrencies: how many, which masses ? Do they fit quark model multi-plets ?  (1900): baryonium ? hybrid meson ?  f 0 (980) vs  cross-sections: evidence of 4-quark f 0 (980) Structure ? Observations of  (1900) Competitors: same as above (VEPP2000 limited to 2 GeV)

Radiative decays : a tool for low mass meson physics  decays : source of  Pseusoscalar Mesons [~ 2 ×10 9  and ~ 10 7  ’ with 50 fb -1 ]            e + e -  ’        ’        ’         Scalar mesons [ , , KK] f 0 (980), a 0 (980)  KK Radiative decays of vector recurrencies to scalar mesons: e.g.  (  (1700)  f 0 (1370)  )/  (  (1700)  f 0 (1500)  ) useful for understanding the “second” scalar multi-plet. Competitors ( on ,  ’ ): AND high flux hadronic machines probably “complementary” to DANAE

 physics : study of 0 ++ and 0 -+ hadronic states L int = 1 fb -1  s = 1 GeV: low mass spectrum [ , ,  threshold]  s = 2.4 GeV: extend to the region of  ’, f 0 and a 0,  and KK thresholds.

Is a Small Angle Tagger needed ? Probably Yes, to reduce the hadronic backgrounds (expecially at the  energy) BUT: it limits the accessible part of the spectrum Simulated  spectra with and without  s = 1 GeV and 2.4 GeV

      : search for the , the lowest mass scalar meson. Fundamental ingredient to assess the 4quark nature of the scalar multi-plet. Recent estimate of the  effect on e + e -  e + e -      cross-section (F.Nguyen, F.Piccinini and A.D.Polosa hep-ph/ )

Time-Like Form Factors of the Baryons: Poor experimental information in the t-l: Neutron vs. Proton, asymptotic behaviours,…. Open problem in the s-l: (|G E |/|G M |) p vs q 2 : 2  contribution Polar angle distribution  |G E (s)| and |G M (s)| asymmetry in   2  contribution ( A  0 ) Polarization of the outgoing nucleon  phase difference  E -  M even with unpolarized e + e - beams From a complete measurement at  s: |G E (s)| |G M (s)|  E -  M and A

Sensitivity (model dependent) Numerical simulation assuming: 1 month data cm -2 s -1,20 bin 0.1 GeV 2 large 1/s 5 behaviour of the cross-section A ~ 0.2 G E (  6% effect to explain s-l discrepancy) Angular distributions Polarisation measurement vs.  Competitors: B-factories (rad.ret.) proton only, in progress Novosibirsk: proton and neutron up to 2 GeV GSI: proton only, but pol.: >2013

Systematic of KN interactions using ~monochromatic kaons from  decays:  K ± interactions on gas (He, H 2,..);  K L interactions on gas and targets (including regeneration); Several millions of events expected Motivations (apart from hypernuclei): g KN  and g KN  are ~ unknown  (1405) assessment Radiative captures

2. Detector considerations For the DANAE program a general purpose detector is required with the following general features: (1)Full angular coverage; (2)Efficient tracking down to low momentum particles; (3)Hermetic calorimeter efficient down to low energy  ; (4)Good particle identification. + Some “special” features:  Small Angle Tagger for  physics;  Polarimeter for proton and neutrons;  Neutron detector efficient for kinetic energies ~ 3 < E kin < 300 MeV.

Assuming one interaction region only we have studied the possibility of using KLOE as “base” detector; Open questions:  need of a vertex detector (       e + e -,   K + K - , multi-hadrons);  need to improve calorimeter granularity (     , a 0, f 0  5  );  Small Angle Tagger vs. machine configuration;  Neutron detection with the KLOE calorimeter (a study is in progress on this point);  How to do the polarimeter ?  Compatibility between polarimeter and vertex detector.

3. An higher energy option: the  – charm factory e + e - machine: 3 <  s < 3.8 GeV ; L = cm -2 s -1 (present machines ×10) L int = 100 fb -1 / year large potentialities in flavour physics to be considered within the super-flavour factory project Competitors: CLEO-C is running: the goal is to collect < 10 fb -1 between J/ ,  (3770) and D s D s threshold by 2008 BEPC-II will start in 2007: goal L = cm -2 s -1 B-factories are running: many  and charm physics results Super-B-factories: discussions are open (see DIF06)

(1) Hidden Charm physics : analysis of charmonium Precise extraction of SM parameters (  S, m C ) Charmonium decays (e.g. J/    c ) Exotic Spectroscopy in the charmonium decays Search for new physics (LFV, EDM,…) (2) Open Charm physics : use e + e -   (3770)  DD With 100 fb -1 (1 year):  CP Violations and D mixing Charm decays are important for analyzing B-decays (3)  –physics LFV:   level hadronic decays: g-2 precision measurement of mass and couplings

4. Final remarks There is a wide experimental program for DANAE complementary to Kaon physics. Motivations come from hadron physics and from precision tests of the Standard Model. General considerations:  The energy increase is a fundamental ingredient.  “ Ultimate ” and complete measurements.  KLOE with some upgrades can be well-suited for such a program. The  – charm factory has to be considered as an important option in the frame-work of the Super-Flavour Factory.