Hadronic physics at KLOE Salvatore Fiore on behalf
Hadronic physics at KLOE Salvatore Fiore (on behalf of the KLOE collaboration) Università di Roma “La Sapienza” and sez. INFN Roma Salvatore Fiore XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 1
Talk outline • • DAFNE and KLOE Scalar Mesons v v f 0(980) B. R. determination and f 0(980) fit to the , spectra. a 0(980) 0 5 (f 0+a 0) K 0 K 0 Ks. Ks sensitivity evaluation). • Pseudoscalar Mesons v v v - ’ mixing angle and ’ gluonic content 0 (dalitz plot fit) mass • e+e- cross-Section below 1 Ge. V • Kaon physics Salvatore Fiore XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 2
Physics at a – factory: a window on the lowest mass mesons decays give access to light mesons (scalar, pseudoscalar, vector) These processes allow to study the structure of these mesons, in particular their s-quark content via couplings with the (ss) 0 -+ 1 -- (1020) KK ' 0++ a 0(980) f 0(980) (770) Direct decay Radiative decay -emission Main decay channels Branching fraction K+K- 49. 2 % K SKL 34. 0 % + 15. 3 % 1. 301 % 0. 125 % ’ 6. 2 × 10 -5 ~ 10 -4 7÷ 8 × 10 -5 + “radiative return” to + - #events in KLOE data = Br. F. × 8 × 109 ~108 ; ~105 ’, , Salvatore Fiore XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 3
The DAFNE e+e F-factory : an e+e- collider with center of mass energy s=m( )=1019. 4 Me. V • (e+e )~3 b • Separate e+e- rings to reduce beam-beam interactions • crossing angle: 25 mrad • Bunch crossing every 2. 7 ns • injection during acquisition integrated Luminosity 2001 -5: L dt = 2. 5 fb-1 L Salvatore Fiore 32 peak=1. 5× 10 cm-2 s-1 XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 4
The KLOE experiment Be beam pipe (spherical, 10 cm , 0. 5 mm thick) + instrumented permanent magnet quadrupoles (32 PMT’s) • Drift chamber (4 m 3. 75 m, CF frame) Gas mixture: 90% He + 10% iso-C 4 H 10 12582 stereo sense wires almost squared cells Calorimeter lead/scintillating fibers (1 mm ), 15 X 0 4880 PMT’s 98% solid angle coverage • Superconducting coil (B = 0. 52 T) Salvatore Fiore XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 5
KLOE detector specifications p/p 0. 4 % (tracks with > 45°) xhit 150 m (xy), 2 mm (z) xvertex ~1 mm (M ) ~1 Me. V Salvatore Fiore E/E 5. 7% / E(Ge. V) t 54 ps / E(Ge. V) 50 ps vtx( ) ~ 1. 5 cm (neutral vertex resolution) XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 6
Scalar mesons Salvatore Fiore XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 7
Scalar Mesons Mass (Ge. V/c 2) (1020) 1. f 0(980) k(800) (500) 0. I=0 I=1/2 Salvatore Fiore Scalar Mesons Spectroscopy: f 0(980), (500) and a 0(980) are accessible through S (k not accessible) a 0(980) Questions: 1. Is (500) needed to describe the mass spectra ? 2. “couplings”of f 0(980) and a 0(980) to |ss> and to KK, and . allows to investigate the inner structure: 4 -quark vs. 2 -quark vs. KK molecule I=1 XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 8
Previous results KLOE already published f 0 and a 0 results based on a sample 20 times smaller (20 pb-1) than the statistics of the analyses a 0(980) 0 presented in the following (~400 pb-1): Old f 0(980) analysis background: subtracted assuming no interference with f 0 e+ e- 2(1) 1(2) BR = (1. 08± 0. 03 stat± 0. 03 syst± 0. 04 norm)x 10− 4 Physics Letters B 537 (2002) 21– 27 + - 0 BR : = (8. 51± 0. 51 stat± 0. 57 syst)x 10− 5 + - 0 =(7. 96± 0. 60 stat± 0. 40 syst)x 10− 5 Physics Letters B 536 (2002) 209– 216 sis y l na a d l O Salvatore Fiore Physics Letters B 536 (2002) 209– 216 XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 9
Definition of the relevant couplings Kaon Loop K+ K K-- f 0, a 0 Salvatore Fiore f 0, a 0 (Achasov - Ivanchenko Nucl. Phys. B 315(1989)465, Achasov - Gubin Phys. Rev. D 63(2001)094007, Achasov - Kiselev Phys. Rev. D 68(2003)014006 ) S to kaons f 0 to (I=0) a 0 to (I=1) Coupling ratio (S=f 0 or a 0) No Structure (G. Isidori et al. , JHEP 0605(2006)049) g S g. SKK=g. SK+K-=g. SK 0 K 0 gf 0 =√ 3/2 gf 0 =√ 3 gf 0 ga 0 Rf 0=(gf 0 K+K-/ gf 0 )2 Ra 0=(ga 0 K+K-/ ga 0 )2 (Ge. V-1) (Ge. V) XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 10
The analysis Event selection: v 2 tracks with t>45 o; missing momentum >45 o (large angle) v pion identification through tracking, Time of Flight and Shower shape v 1 photon matching the missing momentum 6. 7 × 105 events / 350 The + - final state is dominated by: Initial State Radiation Final State Radiation Events pb-1 f 0(980) signal Afb ISR FSR Salvatore Fiore m( ) (Me. V) XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio data MC no f 0 MC with f 0 m( ) (Me. V) 11
Fit of the mass spectrum We use 2 different models for the scalar amplitude : Kaon-loop (KL) No-Structure (NS) An acceptable fit is obtained with both models: P(c 2)(KL)=4. 2% P(c 2)(NS)=4. 4% P. L. B 634 , 148 (2006) Mass values ok gf 0 K+K-> gf 0 “Large” coupling to the B. R. ( f 0(980) ) = 2. 1 2. 4 × 10 -4 (from integral of |Amplitude|2) Salvatore Fiore XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 12
The analysis Event selection: v 5 photons with >21 o ; no tracks; v Kinematic fit energy-momentum conservation; v Kinematic fit 0 masses: choice of the photon pairing to 0’s 4 × 105 events / 450 pb-1 analysis of Dalitz-plot 2 components in the Dalitz-plot Non resonant Resonant Salvatore Fiore XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 13
Dalitz plot fit Models: Improved Kaon-Loop (introducing the (500 “No Structure” A good fit is obtained with both models: P(c 2)(KL)=14% P(c 2)(NS)= 4% f 0(980) param. NS model KL model mf 0 981 ÷ 987 976 ÷ 987 g f (Ge. V-1) 2. 5 ÷ 2. 7 - gf (Ge. V) 1. 3 ÷ 1. 4 ÷ 2. 0 gf. KK 0. 1 ÷ 1. 0 3. 3 ÷ 5. 0 0. ÷ 0. 9 3. 0 ÷ 7. 3 (Me. V) (Ge. V) R=g 2 f. KK /g 2 f Comments: § (500) is needed in KL fit [p(c 2) ~ 10 -4 14% !] (best parameters are: M=462 Me. V, =300 Me. V – Imposed to the fit); § f 0(980) parameters agree with analysis KL R > 1 (gf 0 KK > gf 0 ) § NS fit gives large g f 0 but R<1 (? ? ); § BR extracted: integral of |scalar amplitude|2 Accepted by EPJC (hep-ex/0609009) With BR( ) ~ 1/2 × BR( ) and neglecting KK: BR( f 0(980) ) = (3. 1 ÷ 3. 5) × 10 -4 , ( f 0(980) ) Salvatore Fiore = 1. 2 ÷ 1. 6 ke. V XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 14
The 0 analysis To extract the relevant a 0(980) parameters we fit the M spectrum Two different models exploited: 1. recoil Kaon loop (5 parameters) K+ g KK ga 0 a 0 Ma 0, ga 0 KK 2/(4 ), ga 0 π/ga 0 KK, Br( π0 ), K 0 (phase between scalar and (Achasov - Ivanchenko Nucl. Phys. B 315(1989)465, vector ampl. ) Achasov - Gubin Phys. Rev. D 63(2001)094007, Achasov - Kiselev Phys. Rev. D 68(2003)014006 ) 2. SS E R G RO e+ P IN 0 No structure (8 parameters) Ma 0, ga 0 π, g a 0 , ga 0 KK, c 0 and c 1 (complex) [ a 0 = (m; ga 0 π , ga 0 KK)] Salvatore Fiore e- a 0 ga 0 (G. Isidori et al. , JHEP 0605(2006)049) XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 15
Analysis scheme • dominant scalar contribution from a 0(980) with a 0(980) 0 (exp. Br 7 -8 10 -5 – KLOE 2000 data) • vector contribution VP; V P' (V = , P, P' = , 0) (exp. Br 0. 3 -0. 5 10 -5 - VDM calculations) • 5 final state Analyzed sample: Ldt = 424 pb-1 Pre-selection of 5 photon events kinematic fit Background Process Exp. S/B (MC) f 0(980) 0 0 f 0 0. 7 e+e 0 0 0. 4 ; 0 5 70 ; 0 0 0 7 0. 2 ; 3 15 0 0 30 Total S/B Salvatore Fiore lost or merged photons accidental or split clusters 0. 1 XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 16
7 rejection 3 event rejection E 1+E 2+E 3 (Me. V) 2 0 (2 nd fit)<24 Signal (a 0 ) 7 π0 f 0 3 a 0 E 1+E 2+E 3 < 980 Me. V m (Me. V) ω 0 7 f 0 3 a 0 0 0 d 1 |M(1) - M(2) | =| M | (Me. V) d 2 0 rejection M (Me. V) Cut: | M |< d 1. OR. | M |> d 2. OR. Salvatore Fiore (ω 0)<30° | M |-d 1 (Me. V) . OR. (ω 0)>60° XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 17
Background evaluation • We rely on MC simulation for the description of the background shape and determine the several background components directly on data • A weight (Nfit / Nexpected(MC)) for each process has been determined from data • data ω 0 7 f 0 3 Salvatore Fiore 1+cos 2 Background subtracted XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 18
Preliminary results (I) • • • N - i. Bi = 13099 172 events = 37. 9 % L = (424. 0 2. 5) pb-1 (0. 6 % uncertainty – EPJC 47) = 3090 nb from ( ) = (40. 2 1. 0) nb Br( ) = (39. 38 0. 26) % ary n i m i l Pre Br( 0 ) = (6. 70 0. 09 stat 0. 24 syst) 10 -5 Salvatore Fiore XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 19
Preliminary results (II) Br( 0 ) Achasov-Ivanchenko Nucl. Phys. B 315(1987), 465 Achasov-Gubin Phys. Rev. D 56(1997), 4084 Close-Isgur-Kumano Nucl. Phys. B 389(1993), 513 Kalashnikova et al. , Eur. Phys. J. A 24(2005), 437 Br( 0 ) = (6. 70 0. 09 stat 0. 24 syst) 10 -5 To extract the relevant a 0(980) parameters we have to fit the M spectrum Salvatore Fiore Systematics Br/Br Bckg subtraction 1. 7 % Photon efficiency curves 1. 2 % Analysis cuts 1. 7 % Luminosity 0. 6 % 2. 5 % Br( ) 0. 7 % Total 3. 7 % XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 20
Kaon loop fit Combined fit: charged and neutral channel ( ) ( π+π π0) y r a in im l e Pr Salvatore Fiore XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 21
Couplings: ga 0 /ga 0 KK and f 0/a 0 ga 0 /ga 0 KK = mixing angle of s and non-s quarks in f 0 and KL – combined gf 0 KK/ga 0 KK Kaon loop (f 0 0 0) (f 0 + ) Achasov-Ivanchenko Nucl. Phys. B 315(1987), 465 Achasov-Gubin Phys. Rev. D 56(1997), 4084 Bugg Eur. Phys. J. C 47(2006), 45 Eur. Phys. J. C 47(2006), 57 Close-Isgur-Kumano Nucl. Phys. B 389(1993), 513 Kalashnikova et al. , Eur. Phys. J. A 24(2005), 437 Salvatore Fiore XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 22
In progress: v v Kaon Loop model: meson couples to f 0(a 0) through a charged kaon loop K+ f 0(a 0) K 0 K- K 0 g KK gf 0(a 0)KK (Achasov, Gubin Phys. Rev. D 64: 094016, 2001) Linear sigma model: same graph as kaon loop, different coupling evaluations for g KK and gf 0(a 0)KK (Escribano, hep-ph/0607325) Analysis scheme • We look for KSKS events, with both KS decaying in + • Trigger requirement • Two Vertices close to IP (regeneration rejection) • # of tracks: two tracks attached to each vertex are required • Cut on KS reconstructed invariant mass and momenta • Cut on E 2 miss-P 2 miss Salvatore Fiore XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 23
Preliminary: efficiency and sensitivity B. R. (10 -8) Escribano ¨The preliminary selection efficiency we obtained is 24. 2% ¨The expected number of background events is 7 B. R. sensitivity: with 420 pb-1 Achasov y r a @ 90%C. L in m li e MC sample Pr 7. 5· 10 -8 Evaluated according to: G. J. Feldman and R. D. Cousins, Phys. Rev. D 57 (1998) 3873 Salvatore Fiore XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 24
Pseudoscalar mesons Salvatore Fiore XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 25
BR /BR : Motivations of this analysis • BR can probe the ss and gluonium content of • The ratio R= BR /BR can be related to the mixing parameters and determine the mixing angle in the flavor basis P, the best parameter for a description of the mixing • The two mixing parameter, has emerged from Ec. PT and phenomenological analyses, in the flavor basis are equal apart from terms which violate OZI-rule Method: measurement of using similar and ’ decay chains: 7 for the ’, 7 for the Salvatore Fiore XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 26
Br( )/Br( ) 427 pb-1 (’ 01 -’ 02 data) N( ) = 1665000 1300 (no bck) signal (no bck) ’ signal (~10% bck) N( 7 ’s) = 3750 60 (Nbckg= 345) N( ´ ) = 3405 ± 61 stat± 28 syst LB P to 29) d e tt 6120 i m Sub -ex/0 p ( he with PDG BR( ) Systematics are dominated by knowledge of ’ branching ratios Previous KLOE results Phys. Lett. B 541 (2002) Salvatore Fiore XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 27
gluonium content Combined analysis to evaluate possible gluonium content of ’ (4 constraints in X-Y-plane) (sin g)2=Z 2=0. 14 Salvatore Fiore 0. 04 Y ‘ Using the approach by Bramon et al. [Eur. Phys. J. C 7, 271(1999)] and introducing a possible gluonium content via cos 2 G one can extract the - ’ mixing angle P : LB P o t ) 9 d 2 e 0 itt 612 m b Su -ex/0 p ( he P Black line: imposing Z=0 X ‘ XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 28
analysis The 3 decay is sensitive to isospin symmetry breaking due to light quark mass difference mu md. with: The amplitude decay A(X, Y) is expanded around the center of the Dalitz-plot as: A(X, Y) 2 ≈ 1 + a. Y + b. Y 2 + c. X+ d. X 2+e. XY + f. Y 3 Salvatore Fiore XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 29
Preliminary results Nevents = 1. 377 Mevts (450 pb-1) a correlation b matrix d f a b 1 -0. 226 1 d f -0. 405 -0. 795 0. 358 0. 261 1 0. 113 1 Fitting with the C-violating parameters c and e left free we obtain: v From our preliminary results (hep-ex/0410072) Q 2 v Using Dashen rule Q 2 D= v = 22. 8 0. 4 24. 2 (B. V. Martemyanov and V. S. Sopov, Phys. Rev. D 71 (2005) 017501) J. Kambor, C. Wisendanger and D. Wyler, Nucl. Phys. B 465 (1996) 215 Large NC evaluation confirms deviation from Dashen rule: Q 2 LNC= 22. 0 ± 0. 6 Salvatore Fiore XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 30
Measurement of the (and 0) masses Two recent measurements done with different techniques: v GEM (COSY) p+d 3 He+ M( )=(547311 ± 28 ± 32) ke. V/c 2 (missing mass technique) v NA 48 (CERN) -+p n+ M( )=(547843 ± 30 ± 41) ke. V/c 2 ( 3 0 reconstruction) 8 s discrepancy: d. M(h)=(532 ± 41 ± 52) ke. V/c 2 (errors added in quadrature) KLOE: ; check with 0 ; 0 Technique: kinematic fit mostly based on photon positions and timing; energy-momentum and vertex position from large angle Bhabha scattering 3 Dalitz-plot The and the peak are well defined Mass (Me. V) Salvatore Fiore XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 31
Preliminary results v. The v statistical uncertainty is ~negligible Systematic uncertainties from knowledge of s and vertex position KLOE (work in progress to reduce it) NA 48 The mass is in agreement with NA 48 and in disagreement with GEM M( ) = ( 547822 5 stat 69 syst ) ke. V ry a n i m i l e r P mass (Me. V) The mass is well in agreement with PDG value M( 0)KLOE = ( 134990 6 stat 30 syst ) ke. V M( 0)PDG = ( 134976. 6 0. 6 ) ke. V Salvatore Fiore XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 32
e+e- cross-Section below 1 Ge. V Salvatore Fiore XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 33
Motivation for (e+e + ) v Hadronic contribution aµhadr is limiting the standard model prediction for (g-2)µ ! aµhad is estimated by means of a dispersion relation (intrinsically ~1/s 2): v v Experimental input into dispersion integral at low energies where p. QCD is not applicable Dominant channel below 1 Ge. V is e+e , which contributes with ca. 70% to the total value of aµhad (e+e + ) needed with 1% precision! Salvatore Fiore XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 34
(e+e- + ) with ISR: Modern particle factories, such as DAFNE are designed for a fixed center-of-mass energy: s = m = 1. 02 Ge. V in the case of DAFNE Energy-scan not possible! Complementary approach: Consider events with Initial State Radiation (ISR) ISR 0 S. Binner, J. H. Kühn, K. Melnikov, Phys. Lett. B 459 (1999) 279 + ) + e- hadrons) H(M M hadrd (e e hadrons + ISR (e hadr) d. M hadr • Requires precise calculations of the radiator H • Requires precise understanding of effects from Final State radiation (FSR) H. Czyz, A. Grzelinska, J. H. Kühn, G. Rodrigo, Eur. Phys. J. C 33 (2004), 333 Pancheri, Shekhotsova, Venanzoni, Phys. Lett. B 642, (2006) 342 Salvatore Fiore XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 35
First published result: Contrib. to syst. error on a had: Published Result: Phys. Lett. B 606 (2005) 12 ( e+e- ) nb 1400 KLOE 2001 Data 140 pb-1 1200 1000 800 600 200 0. 4 0. 5 0. 6 0. 7 0. 8 M 2 0. 9 (Ge. V 2) Statistical error negligible (1. 5 Million events) Salvatore Fiore 0. 3% 0. 6% 0. 1% 0. 2% 0. 3% 0. 2% Total experim. Syst. 0. 9% Total theoretical Error 0. 9% Luminosity ( LA Bhabhas ) Vacuum polarization FSR corrections Radiator function 40 0 0. 3 Acceptance Trigger Tracking Vertex Offline reconstruction filter Particle ID Trackmass cut Background Unfolding effects 0. 6% 0. 2% 0. 3% 0. 5% TOTAL ERROR KLOE 1. 3% (CMD-2: 0. 9%, SND 1. 3%) XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 36
Work in progress on d /d. M 2: A new analysis is carried out at small photon angles using 2002 data (240 pb-1) with improved machine background and calibration conditions. This alone should allow for a reduction of the total systematic error on to <1%. In addition, one can extract e+e- by performing a normalization with muon events: many effects cancel in the ratio: • Vacuum Polarisation • Luminosity • Radiator function Analysis with photons detected at large angle allows us to access the 2 pion-threshold region. Main limitation is caused by the contribution from model dependent effects of decays ( f 0 , ) and Final State Radiation from pions. Estimate these effects from MC: - Interference • PHOKHARA [EPJ C 47(2006) 617] • Pancheri/Shekhovtsova/Venanzoni [PLB 642 (2006) 342] Salvatore Fiore XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 37
Hadronic physics analyses at KLOE: f 0 Dalitz plot analysis f 0 coupling to , , KK PLB 634(2006) 148 BR( ) to 5% Dalitz plot analysis, stat/syst improvements PLB 537(2002) 21 accepted by EPJ Dependence of vis on √s ' ( ) e+e- + - etc… Salvatore Fiore BR( a 0(980) ) to 10% stat/syst improvements mass measurement, Dalitz plot analysis BR, m spectrum a |had PDG 06 Preliminary PLB 536(2002) 209 Preliminary ( ' / ( to 12%, mixing angle to 5% PLB 541(2002) 45 stat/syst improvements Preliminary mass measurement e+e- ( + -) PLB 561(2003) 65 PDG 06 Preliminary Upper Limit on BR at 10 -5 PLB 606(2005) 276 PDG 06 Upper Limit on BR at 10 -5 PLB 591(2004) 49 PDG 06 a |had (0. 35 < s < 0. 95 Ge. V 2) to ~ 1% PLB 606(2005) 12 down to threshold, normalization Preliminary lept( ) to 1. 5% and lepton universality test PLB 608(2005) 199 PDG 06 XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 38
Kaon physics Of course, the main effort of the KLOE collaboration is on Kaon physics: v Extraction of the Vus element of the CKM matrix from 5 semileptonic decays of neutral and charged kaons test of CKM Unitarity v CPT tests: first measurement of KS semi-leptonic asymmetry v Kaon interferometry in final states: bounds on quantum coherence + CPT violation v Reduced upper bound on KS 0 0 0 CP violating decay v Precision measurement of KS + ( )/ KS 0 0 v Measurement of KL and KS Ch. PT test v Measurement of KL and K± lifetime v Measurement of KL and K± main B. R. s Salvatore Fiore XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 39
Recent Kaon analyses: KS KL CP and CPT violation Quantum Interference Bell-Steinberger rel. + KLOE data KS UL on BR at 10 -7 KS e BR to 1. 3%, form factor slope, charge asymmetry KS / to ~0. 25% KL l Absolute BR’s to ~ 0. 5% KL lifetime from BR)=1 KL lifetime from KL to ~ 0. 5% KL e Form factor slopes KL e BR to ~ 2 % KL BR to 1. 1% KL / to 1. 1% K+ BR to 1. 4% K+ Absolute BR to ~ 0. 27% K± l± Absolute BR’s to ~ 1. 5% K± lifetime two independent measurements etc… Salvatore Fiore PLB 642 (2006) 315 Accepted by JHEP PLB 619 (2005) 61 PDG 06 PLB 636 (2006) 173 PDG 06 Accepted by EPJC PDG 06 PLB 632 (2006) 43 PDG 06 PLB 626 (2005) 15 PDG 06 PLB 636 (2006) 166 PDG 06 Preliminary PLB 638 (2006) 140 PDG 06 PLB 566 (2003) 61 PLB 597 (2004) 139 PLB 632 (2006) 76 PDG 06 Preliminary XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 40
What's next? Measurement of without resonant background from ● Determination of f 0 and FSR parameters Off-peak data + 0 ● (e e ) vs. s ● Search for (600) with off-peak data using the reaction Kaon physics Hadronic physics ● ● Combined fit of both charged and neutral final states and searches for f 0/a 0 KK Single and Double Dalitz decays, decays ●. . . ● ● ● ● 2 fb-1 Measurement of BR(KS e e Improve on UL(KS e e Improve on semileptonic BRs, lifetimes and form factors BR(KL ) to few 10 -3 (K± e± )/ (K± ) to few 10 -2 … Salvatore Fiore 2 fb-1 XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 41
What's next? KLOE 2 A new scheme to increase DAFNE luminosity by a factor O(5) has been proposed by P. Raimondi (crab waist collisions) – test in autumn 2007 If successful a new round of measurements with an improved KLOE detector could start in 2009 The KLOE detector has proven to well face the challenge, nevertheless something can be improved: add an inner tracker add a tagging system for e+e- increase the EMC read-out granularity update / upgrade the data acquisition Salvatore Fiore XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 42
What's next? KLOE 2 v Time evolution of entangled kaon states, reach the sensitivity to the Planck scale: tests of CPT-symmetry and quantum mechanics v e universality (K e / K ) and the mass of the muon neutrino v universality of the weak coupling to leptons and quarks, CKM matrix unitarity v rare KS decays (semileptonic charge asymmetry, KS ) v light mesons: structure of scalars (via interaction), and ’ physics v (e+e- hadrons), muon anomaly, evolution of em v baryon electromagnetic form factors, e+e- pp, nn, v … and more Salvatore Fiore a new exciting challenge! who wants to join us is welcome!!! XLV International Winter Meeting on Nuclear Physics, 14 -21 Jan 2007, Bormio 43
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