1. Recent results from KLOE at DA NE XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES La Thuile, Aosta, Italy, 10 – 17 March 2007 Antonio Di Domenico* on behalf of the KLOE Collaboration *Università di Roma La Sapienza and INFN sezione di Roma, Italy

2. 2 XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 10 – 17 March 2007 A. Di Domenico e + e b W = m = 1019.4 MeV highly pure K S,K L, K +, K beams Kaons at a -factory p K = 110 MeV/c S = 6 mm L = 3.5 m The detection of a kaon at large (small) times tags a K S (K L ) possibility to select a pure K S beam (unique at a -factory, not possible at fixed target experiments) decay mode BR K 49.1% KSKLKSKL 34.1% K L,S K S,L t1t1 t2t2 t=t 1 t 2 f2f2 f1f1 ~10 6 neutral kaon pairs per pb -1 produced in an antisymmetric quantum state with J PC = 1

3. 3 XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 10 – 17 March 2007 A. Di Domenico DA NE performance up to Dec 2005 Integrated Luminosity Day performance: 7-8 pb -1 Best month L dt ~ 200 pb 1 Total KLOE L dt ~ 2500 pb 1 (2001 - 05) L=1.4 x 10 32 cm 2 s 1 Off peak run Peak Luminosity ~2.5 10 9 K S K L pairs ~3.6 10 9 K + K - pairs

4. 4 XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 10 – 17 March 2007 A. Di Domenico Calorimeter Drift chamber E /E 5.7% / E(GeV) t 54 ps / E(GeV) 50 ps (relative time between clusters) ~ 2 cm ( 0 from K L ) p /p 0.4 % (tracks with > 45°) x hit 150 m (xy), 2 mm (z) x vertex ~ 1 mm The KLOE detector 4 m diameter × 3.3 m length 90% helium, 10% isobutane 12582/52140 sense/total wires All-stereo geometry Lead/scintillating fiber 4880 PMTs 98% coverage of solid angle Superconducting coil B = 0.52 T

5. 5 XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 10 – 17 March 2007 A. Di Domenico K S tagged by K L interaction in EmC Efficiency ~ 30% (largely geometrical) K S angular resolution: ~ 1° (0.3 in ) K S momentum resolution: ~ 2 MeV K L crash = 0.22 (TOF) = 0.22 (TOF) K S e K S e K L tagged by K S vertex at IP Efficiency ~ 70% (mainly geometrical) K L angular resolution: ~ 1° K L momentum resolution: ~ 2 MeV K S K S K L 2 K L 2 K S and K L Tagging

6. 6 XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 10 – 17 March 2007 A. Di Domenico K S + - + - 0 K S e + e - M inv [e e hypo] (MeV) Search for the decay K S e + e - ( ) event s election (1.32 fb -1 ) K S tagged by K L crash 2 tracks from IP to EmC with M inv [e+e- hypo] > 420 MeV 2 -like variable based on EmC: and of (T clu -L/ c) for the 2 particles E/p transverse distance between track impact point and the closest EmC cluster further bck rejection P* ( hypo) in the K S rest frame 220 MeV M miss 380 MeV to reject residual SM prediction is low but precise BR(K S e + e - ) = 1.6 10 -15 [Ecker, Pich 91] leaving room for possible new physics effects to be detected MC

7. 7 XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 10 – 17 March 2007 A. Di Domenico K S + - + - 0 K S e + e - M inv [e e hypo] (MeV) Search for the decay K S e + e - ( ) event s election (1.32 fb -1 ) K S tagged by K L crash 2 tracks from IP to EmC with M inv [e+e- hypo] > 420 MeV 2 -like variable based on EmC: and of (T clu -L/ c) for the 2 particles E/p transverse distance between track impact point and the closest EmC cluster further bck rejection P* ( hypo) in the K S rest frame 220 MeV M miss 380 MeV to reject residual SM prediction is low but precise BR(K S e + e - ) = 1.6 10 -15 [Ecker, Pich 91] leaving room for possible new physics effects to be detected MC signal box

8. 8 XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 10 – 17 March 2007 A. Di Domenico optimization of signal box definition on MC: (492 M inv 504) MeV and 2 20 in the signal box, we find N obs = 3 and BKG = 7.1±3.6 from these UL( sig ) = 4.3 @ 90% CL ( without background subtraction UL( sig ) = 6.68 @ 90% CL ) sig = presel sel -rad ( E* < 6 MeV ) = 0.785 0.888 0.8 = 0.558 = 0.6, N ~ 1.5 10 8 UL(BR) = UL( sig ) sig BR N normalize signal counts to K S ( ) counts in the same data set BR(K S e + e - ( )) < 2.1 10 -8 @ 90% CL KLOE preliminary: CPLEAR: < 1.4 10 -7 Search for the decay K S e + e -

9. 9 XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 10 – 17 March 2007 A. Di Domenico K S event preselection (1.6 fb -1 ) K S tagged by K L crash 2 and only 2 s with E 7MeV cos( ) 0.95 (T -R/c) 5 t BR(K S ) is an important test of PT [PRD 49 (1994) 2346] event selection kinematic fit P KS ( ) = P KS (K L crash) M = M KS T = R/c for both s QCAL veto BR = N sig BR 2 0 N 2 0 = presel sel = 0.83 0.63 = 0.52 2 0 = 0.65 Data - MC K S (QCAL veto) ~ 100% on signal (very small accidental loss) K S 2 0 (2 bckg)

10. 10 XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 10 – 17 March 2007 A. Di Domenico count signal events fitting the 2D plot of M and cos in the K S cms with MC shapes Data - MC signal background M (MeV) cos * M (MeV) Data - MC signal free from K L bckg K S K L control sample selected to further check the energy scale on data-MC K S 2 0 (2 bckg)

11. 11 XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 10 – 17 March 2007 A. Di Domenico BR = (2.35 ± 0.14) 10 -6 2.7 from NA48 result 1.5 in agreement with PT O(p 4 ) prediction K S KLOE preliminary:

12. 12 XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 10 – 17 March 2007 A. Di Domenico E clu (MeV) E clu -E eval (MeV) K L e inclusive selection (328 pb -1 ): K L tagged by K S (E miss -|P miss |) in different mass hypothesis to remove ~90% of bck ToF to separate e/ (after PID ~ 0.7% contamination) 2 10 6 K e3 K L vtx -> comparing ToF of K L and the - cluster time cluster position to close the kinematic and evaluate E -> p = 0 = (p K -p -p e -p ) 2 Signal Ke3 out of acceptance not radiative K e3 + - 0 K 3 measurement of BR and the Direct Emission term in the spectrum radiative sample selection: this cut to remove not radiative K e3 E clu 25 MeV to remove accidentals NN trained with EmC infos to remove K 3 and bck reduction: K L control sample to check efficiency, energy and vertex resolutions MC

13. 13 XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 10 – 17 March 2007 A. Di Domenico K L e BR(Ke3 ; E* 30 MeV, * e- 20 0 ) BR(Ke3( )) R = R = (0.92 ± 0.02 stat ± 0.02 syst )% with 2.5 pb -1 ± 0.01 stat % KLOE preliminary: using DE- spectrum calculated in PT O(p 6 ) [Gasser et al. EPJ 40C (2005)205 ] theory [Gasser et al.,EPJ 40C (2005)205 ]: R = (0.96 ± 0.01)% (uncertainty mainly due to the DE term) fit 2D plot of E* and * e- with the MC shapes we measure: E* (MeV) * e- (deg) Data - MC background Signal * e- deg) E* (MeV) MC BR DE < 2.5 10 -5 @ 90% CL KLOE preliminary: BR DE = (-3.1 ± 3.0) 10 -5 KTEV(05) R=(0.916 ± 0.017)% NA48(05) R=(0.964 ± 0.013)%

14. 14 XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 10 – 17 March 2007 A. Di Domenico K L 3 form factor slope 0 1.5% background contamination reduced to 1.5% using NN and TOF measurements relevant for V us and to test e/ universality 4 (MeV) 3 (MeV) 4% contamination further cut on E miss ( +, - )-|p miss | E miss ( -, + )-|p miss | Selection (328 pb -1 ): K L tagged by K S veto on veto on K e3 MC

15. 15 XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 10 – 17 March 2007 A. Di Domenico separation at low energies is difficult 0 slope obtained by fitting the E distribution, combined fit with K Le3 results for +, + 0 = (15.6 ± 1.8 stat ± 1.9 syst ) 10 -3 PRD 70(2004) KTeV PRD 70(2004) 0 = (12.8± 1.8) 10 -3 preliminary NA48 preliminary 0 = (9.1± 1.4) 10 -3 ISTRA+ PLB 589(2004) 0 = (17.1± 2.2) 10 -3 correlation matrix + + 0 1 -0.95 0.31 X 1 -0.41 X X 1 + = (25.6 ± 1.8) 10 -3 + = (1.44 ± 0.79) 10 -3 [PLB 636 (2006) 166] Data Fit 2 /ndf = 21/31 2 /ndf = 21/31 new !! residuals E (MeV) K L 3 form factor slope 0 KLOE preliminary: ~ 5-10% with 2.5 fb -1 E (MeV)

16. 16 XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 10 – 17 March 2007 A. Di Domenico K L [G F ( )/G F (e)] 2 =1.0065(98) cfr with PDG04 1.047(14) K ± [G F ( )/G F (e)] 2 =0.984(25) cfr with PDG04 1.004(16) Slopes K L e3 K L 3 K S e3K e3 K 3 BR 0.4008(15)0.2699(15)7.046(91)×10 -4 0.05047(92)0.03310(81) 50.84(23) ns89.58(5) ps12.367(78) ns V us f + (0) from KLOE results f + (0)=0.961(8) Leutwyler and Roos Z. [Phys. C25, 91, 1984] V ud =0.97377(27) Marciano and Sirlin [Phys.Rev.Lett.96 032002,2006] From unitarity V us ×f + (0) = 0.2187(21) KLOE AV. = 0.2158±0.0006 (~ 0.3%) KLOE AV. = 0.2158±0.0006 (~ 0.3%) using f + (0) = 0.961(8), V ud = 0.97377(27) = 1 – V ud 2 –V us 2 = (-13±10) 10 -4 = 1 – V ud 2 –V us 2 = (-13±10) 10 -4 |V us |f + (0) FlaviaNet code e/ universality KLOE final KLOE preliminary KLOE final KLOE prelim.

17. 17 XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 10 – 17 March 2007 A. Di Domenico Fit results, no constraint 2 /ndf = 0.35/1 P( 2 ) = 0.56 V us = 0.2239(16) V ud = 0.97377(27) =1–V ud 2 –V us 2 =(1.6±1.2 ) 10 - 3 V us – V ud plane V us /V ud = 0.2286( +27 -15 ) V us = 0.2246(20) K l3 KLOE, using f + (0)=0.961(8) V ud = 0.97377(27) Marciano and Sirlin Phys.Rev.Lett.96 032002,2006Inputs get |V us /V ud | from K, widths: (K ( )) ( ( )) V us V ud fK2fK2 f 2 2 (Marciano PRL93 231803, 2004) from the KLOE analysis of 175 pb -1 [PLB 632,76] BR(K + ) = 0.6366(9)(15) from lattice [MILC Coll. 2006] f K /f p = 1.208(2)( +7 -14 ) Fit results, unitarity constraint 2 /ndf = 3.74/2, P( 2 ) = 0.15, V us = 0.2262(9), V ud = 0.97407(22) V ud V us fit with unitarity fit V ud V us V us /V ud

18. 18 XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 10 – 17 March 2007 A. Di Domenico Recent KLOE published results on kaons K S K L QM and CPT tests PLB 642(2006) 315 Bell-Steinberger rel. CP and CPT violation parameters JHEP 0612(2006)011 K S e BR, charge asymmetry, form factor slope PLB 636(2006) 173 NEW PDG06 K S EPJ C48(2006) 767 NEW PDG06 K S upper limit on BR at 10 -7 PLB 619(2005) 61 NEW PDG06 K L e Absolute BRs KL lifetime from Sum BRs =1 PLB 632(2006) 43 NEW PDG06 K L lifetime from K L PLB 626(2005) 15 NEW PDG06 K L BR to 1.1% PLB 638(2006) 140 NEW PDG06 K L e form factor slopes PLB 636(2006) 166 NEW PDG06 K + Absolute BR PLB 632(2006) 76 NEW PDG06

19. 19 XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 10 – 17 March 2007 A. Di Domenico Measurements of K S K L observables used for the CPT test from unitarity : K S 00 K S K S kl3 S L B(K L l3) (A S +A L )/4 i Im x S L K L CPT test: the Bell-Steinberger relation kl3 main uncertainty now comes from (K S )

20. 20 XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 10 – 17 March 2007 A. Di Domenico Re Im CPLEAR: Re Im KLOE result: JHEP12(2006) 011 Assuming =0, i.e. no CPT viol. in decay: GeV < M < GeV at 95% C.L. CPT test: the Bell-Steinberger relation

21. 21 XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 10 – 17 March 2007 A. Di Domenico K S K L : test of quantum coherence

22. 22 XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 10 – 17 March 2007 A. Di Domenico K S K L : test of quantum coherence Decoherence parameter:

23. 23 XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 10 – 17 March 2007 A. Di Domenico Fit including t resolution and efficiency effects + regeneration S, L m fixed from PDG From CPLEAR data, Bertlmann et al. (PR D60 (1999) 114032) obtain: KLOE result: with 2.5 fb -1 : K S K L : test of quantum coherence as O( high sensitivity to Decoherence parameter: PLB 642(2006) 315 In the B-meson system, BELLE coll. (quant-ph/0702267) obtains: (380 pb -1 )

24. 24 XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 10 – 17 March 2007 A. Di Domenico | | could be at most: In presence of decoherence and CPT violation induced by quantum gravity (CPT operator ill-defined) the definition of the particle-antiparticle states could be modified. This in turn could induce a breakdown of the correlations imposed by Bose statistics (EPR correlations) to the kaon state [Bernabeu, et al. PRL 92 (2004) 131601, NPB744 (2006) 180]: K S K L : CPT violation in correlated K states KLOE result ( measured for the first time) PLB 642(2006) 315 with L=2.5 fb -1 : Re Im 0 0

25. 25 XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 10 – 17 March 2007 A. Di Domenico Conclusions KLOE has obtained new preliminary results on: - BR(K S e + e - ( )) < 2.1 10 -8 @ 90% CL - BR (K S ) = (2.35 ± 0.14) 10 -6 - K L e -> R = (0.92 ± 0.02 stat ± 0.02 syst )%, BR DE < 2.5 10 -5 @ 90% CL - K L 3 form factor slope 0 = (15.6 ± 1.8 stat ± 1.9 syst ) 10 -3 Recent KLOE measurements greatly improve knowledge of V US ; Final results on K l3, and K lifetime (two different methods see P. Massarottis talk) are under way; Several parameters related to CPT and QM tests are measured at KLOE, Re( and Im( for the first time; With the analysis of the full data sample (2.5 fb -1 ) KLOE will further improve all results; KLOE and DA NE are going to be upgraded.

26. 26 XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 10 – 17 March 2007 A. Di Domenico KLOE-2 Physics issues: Neutral kaon interferometry, CPT symmetry & QM tests Kaon physics, rare K S decays, physics Light scalars, physics Hadron cross section at low energy, muon anomaly (baryon electromagnetic form factors, e + e - pp, nn, KLOE-2 at upgraded DA NE KLOE-2 Detector upgrade issues: Inner tracker R&D Calorimeter, increase of granularity FEE maintenance and upgrade Computing and networking update tagging system etc.. (Trigger,software, …) Proposals to upgrade DA NE in luminosity (and energy): Crabbed waist scheme at DA NE (proposal by P. Raimondi) - increase L by a factor O(5) - requires minor modifications - relatively low cost - Experimental test at DA NE in autumn 2007 - If successful KLOE-2 data taking could start already in 2009