1. Experimental setup Data taking Vus CPT a  had f 0 KLOE - May 20, 20081 The KLOE experiment at the Frascati  -factory

2. Experimental setup Data taking Vus CPT a  had f 0 KLOE - May 20, 20082 The KLOE detector Multi-purpose detector optimized for K long physics  KL ~ 51 ps  c| DAFNE ~340 cm Huge, transparent Drift Chamber in 5.2 kGauss field of a SC coil. Carbon fiber walls, 55000 stereo wires, 2m radius, 4m long, mostly He gas mixture. Momentum resolution:  (p T )/p T ~0.4% Lead-Scintillating Fiber Calorimeter with excellent timing performance. 24 barrel modules, 4m long + C-shaped End- Caps for covering 98% of the solid angle. Time resolution:  T = 54 ps/  E(GeV)  50 ps. Energy resolution:  E /E = 5.7% /  E(GeV)

3. Experimental setup Data taking Vus CPT a  had f 0 KLOE - May 20, 20083 2001-2005 L int = 2482 pb -1 2004-2005 L int = 1990 pb -1 Best conditions: Sept/Oct/Nov 2005  179/189/194 pb -1 stable luminosity, beam energy and backgrounds Five years of continuous efforts to increase circulating currents maintaining low bck level at the IR and providing stable running conditions for the experiments Continuous Beam Re-filling to obtain integrated luminosities > 150 pb -1 per month KLOE Data Taking

4. Experimental setup Data taking Vus CPT a  had f 0 KLOE - May 20, 20084 min {(p miss -E miss )|    , (p miss -E miss )|       e    Data K L   e       : K L vertex reconstructed in DC Fit to p miss - E miss spectrum K L         Photon vertex reconstructed by TOF Absolute BR: (N sig /N tag )  1/  sig  geo function of  L Using the constraint  BR(K L )=1, BR ( K L  e ) = 0.4007  0.0006 stat  0.0014 syst BR ( K L  ) = 0.2698  0.0006 stat  0.0014 syst BR ( K L  0  0  0 ) = 0.1997  0.0005 stat  0.0019 syst BR ( K L  +  -  0 ) = 0.1263  0.0005 stat  0.0011 syst  KL = (50.72  0.17 stat  0.33 syst ) ns Result from direct KLOE measurement,  L = (50.92  0.17 stat  0.25 syst ) ns Average:  L = 50.84  0.23 ns   /  ~ 4.5  10 -3 PLB 632 (2006) 43 PLB 626 (2005) 15 PLB 636 (2006) 166 Dominant K L ’s BR and  L

5. Experimental setup Data taking Vus CPT a  had f 0 KLOE - May 20, 20085 Semileptonic K ± BR’s Semileptonic decays tagged by 2-body decays, K  0 and K  Four different samples analyzed, tagged by K +  +  0, K -  -  0, K +  +, K -  - Lepton mass from p and TOF  : M 2 lept = p 2 lept [ c 2 / L 2 lept (T lept - T  + L  /c) 2 – 1 ] Consistent results, giving BR(K ± e3 ) = 0.0497 ± 0.0005 BR(K ±  3 ) = 0.0323 ± 0.0004 Event counting from the fit of the M 2 lept distribution with the MC-predicted spectra for K ± e3, K ±  3 and background. The measurements are fully inclusive of radiative decays, whose acceptance is known from MC simulation [ C. Gatti, Eur. Phys. J., C 45 (2006) 417] BR \ TagK+2K+2 K+2K+2 K-2K-2 K-2K-2 BR(K e3 )0.0495(7)0.0493(10)0.0497(8)0.0502(10) BR(K  3 )0.0322(6)0.0322(9)0.0323(5)0.0327(9) JHEP 0802 (2008) 098

6. Experimental setup Data taking Vus CPT a  had f 0 KLOE - May 20, 20086 K ± Lifetime Four independent measurements of the K ± lifetime, exploiting both, -the accurate vertex reconstruction (tracking) and -the excellent time resolution of the calorimeter (TOF) All of the decay channels tagged by K ±  decays have been used for the Kaon vertex reconstruction, while the X  0 channels have been selected for the TOF measurement.  (K ± ) = 12.347 ± 0.030 Efficiencies are evaluated with data control samples. From vertex measurement we obtain  (K ± ) = 12.364 ± 0.031 stat ± 0.031 syst and from TOF  (K ± ) = 12.337 ± 0.030 stat ± 0.020 syst Normalized correlation, from common events (systematics are pratically uncorrelated ) is 30.7%. Averaging the results, we obtain: K -, l K +, l K -, t K +, t JHEP 0801 (2008) 073

7. Experimental setup Data taking Vus CPT a  had f 0 KLOE - May 20, 20087 Semileptonic form factors Form Factor dependence from momentum transfer used in the evaluation of phase space integral  Phys.Lett.B636(2006)166 K L  e t/m 2  from K L  New parametrization used. Series expansion in terms of one parameter only for both, f + and f 0 Combined  e and  results: I(K 0 e3 )I(K 0  3 )I(K ± e3 )I(K ±  3 ) 0.15477(35)0.10262(47)0.15913(36)0.10559(48) JHEP 0712 (2007) 105 K L 

8. Experimental setup Data taking Vus CPT a  had f 0 KLOE - May 20, 20088 BR(  e ) = (7.046 ± 0.077 ± 0.049 )  10  fractional error: 1.3% = 1.1% stat  0.7% syst A S = ( 1.5 ± 9.6 ± 2.9 )  10  first measurement Charge asymmetry Branching ratio 1 + 4 Re(x + ) = SS LL BR(K S   e )  L BR(K L   e )  S = 6 10  3 10  3 4 10  3 13 10  3 Re x  = (  0.5  3.1  1.8) 10  Pure K S beam, tagged by K L interactions in the calorimeter. TOF e/  ID, fit to E miss - p miss spectrum K S      events in the same sample for K S counting PLB 636 (2006) 173 K s  e  : BR, A s, Re x +

9. Experimental setup Data taking Vus CPT a  had f 0 KLOE - May 20, 20089  (K   l )  C 2 K (G 2 F M 5 K /192   ) f 2 + (0)|V us | 2 I( t ) S EW (1 +  EM +  SU(2) ) f + (0)|V us | from Kl3 decays Electromagnetic and Isospin corrections + phase space integrals to obtain independent measurements of f + (0)|V us | The consistency of the measurements validates isospin corrections = 0.2157 ± 0.0006 | e |  competitive with that obtained from leptonic  decays g 2 e /g 2  = 1.000 ± 0.008 is a test of lepton universality

10. Experimental setup Data taking Vus CPT a  had f 0 KLOE - May 20, 200810 Radiative corrections largely cancel out in the ratio f K /f  ratio: better precision from Lattice, scale- uncertainties reduced Using f K /f  =1.189(7) (HPQCD/UKQCD Coll., arXiv:0706.1726)) and KLOE BR(K +   + ) : |V us /V ud | 2 = 0.0541  0.0007 Tag from K -   Subtract       l   background from data Event count in the {225, 400} MeV window of the momentum distribution in the K rest frame BR(K +    = 0.6366  0.0009 stat  0.0015 syst PLB 632 (2006) 76 BR(K +  + (  ))

11. Experimental setup Data taking Vus CPT a  had f 0 KLOE - May 20, 200811 Unitarity test of the CKM matrix JHEP 0804(2008)059 From KLOE average and using the recent Lattice result f + (0)=0.9644±0.0049 [ RBC/UKQCD Coll., arXiv:0710.5136], V 2 us = 0.05004±0.00058 KLOE has also obtained, in agreement with Lattice results, f + (0)=0.964±0.023 from the measurement of the semileptonic form factor parameters, using Callan- Treiman relation and f k /f  = 1.189±0.007 From superallowed nuclear  -decay, V 2 ud = 0.94903±0.00051 The fit including KLOE V 2 us /V 2 ud determination from K +  +  decays provide the CKM unitarity test: 1 -|V us | 2 - |V ud | 2 = 0.0004 ± 0.0007

12. Experimental setup Data taking Vus CPT a  had f 0 KLOE - May 20, 200812 Bounds on New Physics from K  decay Interesting limits in tan  -M H± plane have been obtained from K  decay H ± exchange can compete with the W ± exchange for the helicity-suppressed mode K  [G.Isidori and P.Paradisi,Phys.Lett.,B639(2006),499] The observable used is that is unity in the SM and would be lower by the interference between W ± and H ± amplitudes R l23 = 1 - m2K+m2K+ m2+m2+ m2H+m2H+ m2K+m2K+ tan 2   0 tan  1 - () R l23 = V us (K  2 )V ud (0 +  0 + ) V us (K l3 ) V ud (   2 )  From KLOE measurements, lattice calculations and V ud results reported in the previous slides, we obtain and the limits that in the figure are compared with those from B  decay R l23 = 1.008 ± 0.008

13. Experimental setup Data taking Vus CPT a  had f 0 KLOE - May 20, 200813 NEW: Re  (159.6 ± 1.3)  10 -5  Im  (0.4 ± 2.1)  10 -5 NEW: Re  (159.6 ± 1.3)  10 -5  Im  (0.4 ± 2.1)  10 -5 OLD: Re  (164.9 ±2.5) 10 -5  Im  2.4 ±5.0) 10 -5 - Uncertainty on Im  is now dominated by   and   - Semileptonic sector contributes by ~ 10% Assuming no CPT violation in the decay amplitudes, (  = 0): |  M| < 3  10 -19 GeV 1.KLOE: new BR(K L      2.KLOE:  A, x,  S=  Q from K S  e 3.KLOE: new limit on  K S  3    4.No results already constrained by BSR have been used  2-3 improvement CPT test from Bell-Steinberger relation From Im  and Re  get limits on  M= (m K 0 - m K 0 ) and  = (  K 0 -  K 0 ) JHEP 0612 (2006) 011

14. Experimental setup Data taking Vus CPT a  had f 0 KLOE - May 20, 200814 interference term modified introducing a decoherence parameter . Systematics x10 better, completely negligible  K S K L < 0.085  K 0 K 0 < 0.44 10 -5 @ 90% C.L. CPT violation could also change initial state |  | < 2.1 10 -3 @ 95% C.L. PLB 642(2006)315 Decoherence and CPT from neutral Kaon pairs

15. Experimental setup Data taking Vus CPT a  had f 0 KLOE - May 20, 200815     PLB 606(2005)12 2 The anomalous muon magnetic moment a  = (g  - 2)/2 = (116592080 ± 60) 10 -11 E821 Theory : a  = a  QED +  a  weak  + a  had a  had from measurements of the ha- dronic cross section via dispersion relation Dominant low-energy contribution, M 2  < 1 GeV 2 KLOE measurement from e + e -      final state with  at low zenithal angle We obtained a   in the 0.35<s< 0.95 GeV 2 region. Two independent data sets have been analyzed with different trigger conditions and different analysis paths, giving Hadronic cross section a   | 0.35<s<0.95 = (3844± 8 stat ± 35 syst ± 35 theo ) 10 -11 [140 pb -1 data sample] a   | 0.35<s<0.95 = (3892± 6 stat ± 30 syst ± 20 theo ) 10 -11 [242 pb -1 data sample] (preliminary)

16. Experimental setup Data taking Vus CPT a  had f 0 KLOE - May 20, 200816 Low-energy hadronic contribution to a  Consistent set of a   values from all of the low-energy hadronic cross section measurements at e + e - machines The theoretical SM prediction for a  including the e + e - data set differs by more than 3  from the BNL measurement New KLOE analysis confirms the discrepancy K. Hagiwara, A.D. Martin, Daisuke Nomura, T. Teubner

17. Experimental setup Data taking Vus CPT a  had f 0 KLOE - May 20, 200817 Search for the f 0 signal as a deviation on M     from the ISR + FSR shape f 0 (980) region M  (MeV)  S      e + e           Two main contributions to the      final state, separated in the bi-dimensional plot M    vs M     Events/1.2 MeV e + e        events with the photon at large angle (45  <  <135  ) Main contributions: ISR (radiative return to  ) and FSR e+e  e+e   The light scalars : f 0 (980)

18. Experimental setup Data taking Vus CPT a  had f 0 KLOE - May 20, 200818 S g  KK g SKK g S   KK KK  S V g V S  g S   e+e+  e-e- Kaon-loop Predictions of the M  distribution from Kaon-loop and direct scalar coupling to vector mesons, have been compared for both final states,     , and      PLB 634 (2006) 148 EPJ C49 (2007) 473 Experimental distributions have been fitted taking into account the contributions to the final states summarized in the previous slide Data can be described by both the models To fit the      spectrum with predictions from Kaon-loop model, a  (600) contribution must be included KK coupling, in the model with direct scalar coupling to vector mesons, results weaker from      analysis than in the      study. The f 0 (980) structure