Recent results from KLOE at DA NE Antonio

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

Kaons at a f-factory • e+e f sf~3 mb W = mf = 1019. 4 Me. V • highly pure KS, KL, K+, K beams f decay mode BR K+ K 49. 1% K SK L 34. 1% • ~106 neutral kaon pairs per pb-1 produced in an antisymmetric quantum state with JPC = 1 p. K = 110 Me. V/c l. S = 6 mm l. L = 3. 5 m t 2 t 1 f 1 KS, L f f 2 KL, S Dt=t 1 - t 2 The detection of a kaon at large (small) times tags a KS (KL) Þ possibility to select a pure KS beam (unique at a f-factory, not possible at fixed target experiments) A. Di Domenico XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 2

DA NE performance up to Dec 2005 Peak Luminosity L=1. 4 x 1032 cm 2 s 1 Off peak run Day performance: 7 -8 pb-1 Integrated Luminosity Best month L dt ~ 200 pb 1 Total KLOE L dt ~ 2500 pb 1 (2001 - 05) ~2. 5 109 KSKL pairs ~3. 6 109 K+K- pairs A. Di Domenico XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 3

The KLOE detector Superconducting coil B = 0. 52 T Drift chamber Calorimeter Lead/scintillating fiber 4880 PMTs 98% coverage of solid angle s. E/E 5. 7% / E(Ge. V) st 54 ps / E(Ge. V) 50 ps (relative time between clusters) sgg ~ 2 cm (p 0 from KL p+p p 0) 4 m diameter × 3. 3 m length 90% helium, 10% isobutane 12582/52140 sense/total wires All-stereo geometry sp/p 0. 4 % (tracks with q > 45°) sxhit 150 mm (xy), 2 mm (z) sxvertex ~ 1 mm A. Di Domenico XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 4

KS and KL Tagging KL “crash” b= 0. 22 (TOF) K S p +p K S p e +n KS tagged by KL interaction in Em. C Efficiency ~ 30% (largely geometrical) KS angular resolution: ~ 1° (0. 3 in f) KS momentum resolution: ~ 2 Me. V KL 2 p 0 KL tagged by KS p+p vertex at IP Efficiency ~ 70% (mainly geometrical) KL angular resolution: ~ 1° KL momentum resolution: ~ 2 Me. V A. Di Domenico XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 5

Search for the decay KS e+e. SM prediction is low but precise BR(KS e+e-) = 1. 6 10 -15 [Ecker, Pich 91] leaving room for possible new physics effects to be detected MC event selection (1. 32 fb-1 ) • KS tagged by KL crash • 2 tracks from IP to Em. C with Minv [e+e- hypo] > 420 Me. V c 2 -like variable based on Em. C: § S and D of (Tclu-L/bc) for the 2 particles c 2 KS p+p- mp KS p+pf p +p -p 0 K S e + e- § E/p § transverse distance between track impact point and the closest Em. C cluster further bck rejection • P* (p hypo) in the KS rest frame 220 Me. V • Mmiss 380 Me. V to reject residual p+p p 0 Minv [e+e hypo] (Me. V) A. Di Domenico XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 6

Search for the decay KS e+e. SM prediction is low but precise BR(KS e+e-) = 1. 6 10 -15 [Ecker, Pich 91] leaving room for possible new physics effects to be detected MC event selection (1. 32 fb-1 ) • KS tagged by KL crash • 2 tracks from IP to Em. C with Minv [e+e- hypo] > 420 Me. V c 2 -like variable based on Em. C: § S and D of (Tclu-L/bc) for the 2 particles § E/p § transverse distance between track impact point and the closest Em. C cluster c 2 KS p+p- mp KS p+pf p +p -p 0 K S e + esignal box further bck rejection • P* (p hypo) in the KS rest frame 220 Me. V • Mmiss 380 Me. V to reject residual p+p p 0 Minv [e+e hypo] (Me. V) A. Di Domenico XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 7

Search for the decay KS e+e§ optimization of signal box definition on MC: (492 Minv 504) Me. V and c 2 20 § in the signal box, we find Nobs = 3 and m. BKG = 7. 1± 3. 6 § from these UL(msig) = 4. 3 @ 90% CL ( without background subtraction UL(msig) = 6. 68 @ 90% CL ) § normalize signal counts to KS pp(g) counts in the same data set UL(BR) = UL(msig) sig = presel ag-rad pp = 0. 6 , Npp ~ 1. 5 108 pp BRpp sig Npp (E*g < 6 Me. V) = 0. 785 0. 888 0. 8 = 0. 558 KLOE preliminary: BR(KS e+e-(g)) < 2. 1 10 -8 @ 90% CL CPLEAR: < 1. 4 10 -7 A. Di Domenico XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 8

KS gg BR(KS gg) is an important test of c. PT [PRD 49 (1994) 2346] event preselection (1. 6 fb-1 ) § KS tagged by KL crash § 2 and only 2 g’s with Eg 7 Me. V cos(qgg) 0. 95 (Tg-R/c) 5 st BR = Ngg 2 p 0 BR 2 p 0 sig N 2 p 0 gg= presel sel= 0. 83 0. 63 = 0. 52 2 p 0 = 0. 65 event selection § kinematic fit PKS (gg) = PKS(KLcrash) Mgg = MKS Tg = R/c for both g’s § QCAL veto KS 2 p 0 (2 g bckg) Data - MC • KS gg § (QCAL veto) ~ 100% on signal (very small accidental loss) A. Di Domenico XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 9

KS gg §count signal events fitting the 2 D plot of Mgg and cosq*gg in the KS cms with MC shapes • Data - MC signal background cos q*gg KS 2 p 0 (2 g bckg) Data - MC • Mgg (Me. V) § KL gg control sample selected to further check the energy scale on data-MC § signal free from KL gg bckg A. Di Domenico XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 10

KS gg KLOE preliminary: BR = (2. 35 ± 0. 14) 10 -6 § 2. 7 s from NA 48 result § 1. 5 s in agreement with c. PT O(p 4) prediction A. Di Domenico XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 11

KL peng measurement of BR and the Direct Emission term in the g spectrum inclusive selection (328 pb-1 ): radiative sample selection: Eclu -Egeval (Me. V) • KLg vtx -> comparing To. F of KL and the g • KL tagged by KS p+p cluster time • (Emiss-|Pmiss|) in different mass hypothesis to remove ~90% of bck • cluster position to close the kinematic and • To. F to separate e/p (after PID ~ evaluate Eg -> pn 2 = 0 = (p. K-pp-pe-pg)2 0. 7% contamination) Signal 2 106 Ke 3 g out of acceptance not radiative Ke 3 MC f p + p -p 0 Km 3 Eclu(Me. V) bck reduction: • this cut to remove not radiative Ke 3 • Eclu 25 Me. V to remove accidentals • NN trained with Em. C infos to remove Km 3 and p+p p 0 KL p+p p 0 control sample to check g efficiency, energy and vertex resolutions A. Di Domenico XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 12

KL peng • fit 2 D plot of E*g and q*e-g with the MC shapes • we measure: BR(Ke 3 g; E*g 30 Me. V, q*e-g 200) R= BR(Ke 3(g)) theory [Gasser et al. , EPJ 40 C (2005)205 ]: (uncertainty mainly R = (0. 96 ± 0. 01)% due to the DE term) KLOE preliminary: E*g (Me. V) background Signal R = (0. 92 ± 0. 02 stat ± 0. 02 syst)% with 2. 5 pb-1 ± 0. 01 stat% using DE-g spectrum calculated in c. PT O(p 6) [Gasser et al. EPJ 40 C (2005)205 ] KLOE preliminary: BRDE = (-3. 1 ± 3. 0) 10 -5 BRDE < 2. 5 10 -5 @ 90% CL q*e-g (deg) KTEV(05) R=(0. 916 ± 0. 017)% NA 48(05) R=(0. 964 ± 0. 013)% Data - MC • q*e-g (deg) MC E*g (Me. V) A. Di Domenico XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 13

KLm 3 form factor slope l 0 relevant for Vus and to test e/m universality Selection (328 pb-1 ): §veto on p+p : § KL tagged by KS p+p §veto on p+p p 0: 3= Emiss(p+, m-)-|pmiss| 4= Emiss(p-, m+)-|pmiss| 3(Me. V) § further cut on 3(Me. V) §veto on Ke 3: 4% contamination MC 4(Me. V) § background contamination reduced to 1. 5% using NN and TOF measurements A. Di Domenico XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 14

KLm 3 form factor slope l 0 p/m separation at low energies is difficult l 0 slope obtained by fitting the En distribution, combined fit with KLe 3 results for l’+ , l’’+ w e n !! c 2/ndf = 21/31 Data Fit l’+ = (25. 6 ± 1. 8) 10 -3 l’’+ = (1. 44 ± 0. 79) 10 -3 correlation matrix l’+ l’’+ l 0 En(Me. V) 1 residuals [PLB 636 (2006) 166] X X -0. 95 1 X 0. 31 -0. 41 1 KLOE preliminary: l 0/l 0~ 5 -10% with 2. 5 fb-1 l 0 = (15. 6 ± 1. 8 stat ± 1. 9 syst) 10 -3 En(Me. V) KTe. V PRD 70(2004) l 0 = (12. 8± 1. 8) 10 -3 NA 48 preliminary l 0 = (9. 1± 1. 4) 10 -3 ISTRA+ PLB 589(2004) l 0 = (17. 1± 2. 2) 10 -3 A. Di Domenico XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 15

Vus f+(0) from KLOE results KL e 3 BR 0. 4008(15) t KLOE final KL m 3 KS e 3 K m 3 0. 2699(15) 7. 046(91)× 10 -4 0. 05047(92) 0. 03310(81) 50. 84(23) ns D = 1 – Vud 2 –Vus 2 = (-13± 10) 10 -4 using f+(0) = 0. 961(8), Vud = 0. 97377(27) KLOE preliminary 89. 58(5) ps |Vus|f+(0) 12. 367(78) ns e od c et N ia v a Fl <Vus×f+(0)>KLOE AV. = 0. 2158± 0. 0006 (~ 0. 3%) Slopes KLOE fin l + = 0. 0256(18) l + = 0. 0014(8) l 0 = 0. 0156(26) KLOE prelim From unitarity • f+(0)=0. 961(8) Leutwyler and Roos Z. [Phys. C 25, 91, 1984] • Vud=0. 97377(27) Marciano and Sirlin [Phys. Rev. Lett. 96 032002, 2006] Vus×f+(0) = 0. 2187(21) e/m universality KL [GF(m)/GF(e)]2 =1. 0065(98) cfr with PDG 04 1. 047(14) K± [GF(m)/GF(e)]2 =0. 984(25) cfr with PDG 04 1. 004(16) A. Di Domenico XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 16

Vus – Vud plane § get |Vus/Vud| from K, p mn widths: G (K mn(g)) Vus 2 f. K 2 2 G (p mn(g)) Vud fp § from the KLOE analysis of 175 pb-1 [PLB 632, 76] BR(K+ m+n(g)) = 0. 6366(9)(15) (Marciano PRL 93 231803, 2004) Vud Vus § from lattice [MILC Coll. 2006] f. K/fp = 1. 208(2)(+7 -14) Vus Inputs Vus/Vud = 0. 2286(+27 -15) Vus = 0. 2246(20) Kl 3 KLOE, using f+(0)=0. 961(8) Vud = 0. 97377(27) Marciano and Sirlin Phys. Rev. Lett. 96 032002, 2006 Fit results, no constraint fit with unitarity c 2/ndf = 0. 35/1 Vus /Vud 2 P(c ) = 0. 56 Vus = 0. 2239(16) Vud = 0. 97377(27) D =1–Vud 2 –Vus 2=(1. 6± 1. 2 ) 10 -3 Fit results, unitarity constraint c 2/ndf = 3. 74/2, P(c 2) = 0. 15, Vus = 0. 2262(9), Vud = 0. 97407(22) A. Di Domenico XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 17

Recent KLOE published results on kaons KSKL p+p Bell-Steinberger rel. KS pen KS p+p , p 0 p 0 QM and CPT tests CP and CPT violation parameters PLB 642(2006) 315 JHEP 0612(2006)011 BR, charge asymmetry, form factor PLB 636(2006) 173 slope NEW PDG 06 G(p+p )/G(p 0 p 0) EPJ C 48(2006) 767 NEW PDG 06 upper limit on BR at 10 -7 PLB 619(2005) 61 NEW PDG 06 Absolute BR’s KL lifetime from Sum BR’s =1 PLB 632(2006) 43 NEW PDG 06 KL lifetime from KL p 0 p 0 p 0 PLB 626(2005) 15 NEW PDG 06 KL p+p BR to 1. 1% PLB 638(2006) 140 NEW PDG 06 KL pen form factor slopes PLB 636(2006) 166 NEW PDG 06 K+ m+n Absolute BR PLB 632(2006) 76 NEW PDG 06 KS p 0 p 0 p 0 KL pen, ppp A. Di Domenico XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 18

CPT test: the Bell-Steinberger relation Measurements of KS KL observables used for the CPT test from unitarity : a+ = h+ B(KS p+p ) a 00= h 00 B(KS p 0 p 0) a+ 0= t. S/t. L h+ 0* B(KL p+p p 0) a+ g= h+ B(KS p+p g) a 000= t. S/t. L h 000* B(KL p 0 p 0 p 0) akl 3 = 2 t. S/t. L B(KLl 3) [(AS+AL)/4 i Im x+] main uncertainty now comes from h+ a 00 a+ g a 000 (KS) a+ 0 akl 3 (KS) A. Di Domenico XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 19

CPT test: the Bell-Steinberger relation JHEP 12 KLOE result: Re = (159. 6 1. 3) 10 5 Im =(0. 4 2. 1) 10 5 (2006) 0 11 CPLEAR: Re = (164. 9 2. 5) 10 5 Im =(2. 4 5. 0) 10 5 Assuming DG=0, i. e. no CPT viol. in decay: 5. 3 10 19 Ge. V < DM < 6. 3 10 19 Ge. V at 95% C. L. A. Di Domenico XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 20

f KSKL p+p : test of quantum coherence A. Di Domenico XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 21

f KSKL p+p : test of quantum coherence Decoherence parameter: A. Di Domenico XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 22

f KSKL p+p : test of quantum coherence (380 pb-1) • Fit including Dt resolution and Decoherence parameter: efficiency effects + regeneration • GS, GL Dm fixed from PDG KLOE result: PLB 64 2(2006) 315 with 2. 5 fb-1 : as O(|h+ |2) ~ 10 6 = high sensitivity to z From CPLEAR data, Bertlmann et al. (PR D 60 (1999) 114032) obtain: In the B-meson system, BELLE coll. (quant-ph/0702267) obtains: A. Di Domenico XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 23

f KSKL p+p : CPT violation in correlated K states 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, NPB 744 (2006) 180]: |w| could be at most: KLOE result (w measured for the first time) Im w PL B with L=2. 5 fb-1: 64 2( 20 06 )3 15 0 Re w 0 A. Di Domenico XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 24

Conclusions • KLOE has obtained new preliminary results on: - BR(KS e+e-(g)) < 2. 1 10 -8 @ 90% CL - BR (KS gg) = (2. 35 ± 0. 14) 10 -6 - KL epng -> R = (0. 92 ± 0. 02 stat ± 0. 02 syst)% , BRDE < 2. 5 10 -5 @ 90% CL - KLm 3 form factor slope l 0= (15. 6 ± 1. 8 stat ± 1. 9 syst) 10 -3 • Recent KLOE measurements greatly improve knowledge of VUS ; • Final results on K l 3 , and K lifetime (two different methods see P. Massarotti’s talk) are under way; • Several parameters related to CPT and QM tests are measured at KLOE, Re(w) and Im(w) for the first time; • With the analysis of the full data sample (2. 5 fb-1) KLOE will further improve all results; • KLOE and DAFNE are going to be upgraded. A. Di Domenico XLII Rencontres de Moriond on ELECTROWEAK INTERACTIONS AND UNIFIED THEORIES, La Thuile, Italy, 25

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