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Hadron Physics at KLOE and KLOE-2. Camilla Di donato Sez. infn napoli On behalf of kloe and kloe-2 collaborations. Outline. Hadron Physics @ KLOE/2 U-boson Search : e + e - / U Light Meson Spectroscopy : and physics Other KLOE/2 results not discussed here
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HadronPhysics at KLOE and KLOE-2 Camilla Di donato Sez. infnnapoli On behalfofkloe and kloe-2 collaborations
Outline HadronPhysics @ KLOE/2 • U-bosonSearch: e+e-/U • Light MesonSpectroscopy: and physics Other KLOE/2 resultsnotdiscussedhere • PS Transition FF • Physics: • /f0(600) • Studyof (S/PS ) • Pion FF from e+e- / C. Di Donato - Rencontres de Moriond QCD
KLOE and KLOE-2 @ DAFNE e.m. calorimeter resolution d.c. performances DAFNE: e+e- collider @ s 1020 MeV; peak3.1 b C. Di Donato - Rencontres de Moriond QCD
U-Boson Search U C. Di Donato - Rencontres de Moriond QCD
Low Energy Dark Forces Severalunexpectedastrophysicalobservations (PAMELA, ATIC, INTEGRAL, DAMA/LIBRA, CoGent...) couldbeexplainedwith the existenceof a hiddengaugesectorweaklycoupledwith SM through a mixing mechanismof a newGAUGE BOSON (U, A, V)with the photon: [Arkani-Hamedet al. PRD79 015014 (2009)] [Essiget al. PRD80 015003 (2009)] • U mass range: 1 MeV – fewGeV • Couplingconstantofelectricchargeto U: 10-3 • U production/decaythroughphoton mixing C. Di Donato - Rencontres de Moriond QCD
Search for U boson @ KLOE • Meson Decays: U, U, 0 U … • Peculiar of a light meson factory • e+e- collisions: e+e- U • x-sec 1/s : 100 times higher at DAFNE w.r.t. b-factories/ compensate lower luminosity • h-strahlung: e+e- U* Uh • If the hidden simmetry is spontaneously broken by a Higgs-like mechanism, the existence of at least one other scalar particle , can be postulated h Meson can decayto a U bosonwith: for Irreducible background: Dalitzdecay l+l- , ( = 0.7 nb) C. Di Donato - Rencontres de Moriond QCD
PLB706 (2012) 251-255 e+ e- , with +-0 L = 1.5fb-1 BR(e+e-)=1.15 10-4 : producedevents 106 e+e- C. Di Donato - Rencontres de Moriond QCD
PLB706 (2012) 251-255 e+ e- , with +-0 • Wehave 14000 candidates: e+e-with+ - 0 • Verysmallresidualcontaminationfrom • MC Meeshapefrom VMD with FF slopefrom SND (213 events) [PLB504 (2001) 275] • Background extracteddirectlyfrom data C. Di Donato - Rencontres de Moriond QCD
Fit to Mee Shape Usingdecayparametrization from Landsberg85 and F(q2) approx. fromAchasov, Kozhevnikov, Sov. J. Nucl. Phys. 55 (1992) 449 C. Di Donato - Rencontres de Moriond QCD
PLB706 (2012) 251-255 Exclusion plot for Evaluationof UL takesinto account: • Kinematicfactors [Reece-Wang, JHEP0907:051 (200)] • Opening of U+-threshold PLB706 (2012) 2 10-5 @ 90% C.L. for 50 < MU < 420 MeV PRL107 (2011) PRL106 (2011) C. Di Donato - Rencontres de Moriond QCD
e+ e- , with /000 Preliminarystudies on and 000decaychannels produce encouragingresults U.L. can beimprovedby a factor2 C. Di Donato - Rencontres de Moriond QCD
Light Meson spectroscopy +- decay C. Di Donato - Rencontres de Moriond QCD
+ - / Light Mesons: +- • Box Anomaly: are expectedtogetcontributionfromanomaly, Wess Zumino Wittenterm in ChPTLagrangian • AccordingtoEffectiveTheory(HLS: Benayoun, Eur. Phys. J. C31 (2003) 525), theycouldbedescribedby VMD + a directterm • Studies of final state interaction by unitarized extensions: • Picciotto, Phys. Rev. D45 (1992) 1569; • Benayoun, Eur. Phys. J. C31 (2003) 525 • Holstein, Phys. Scripta, T99 (2002) 55 • Borasoy, Nissler, Nucl. Phys. A740 (2004) 362 + - + / VMD CT • Modelindependentmethodbased on ChPT and dispersive analysis: do notfix relative strengthbetweentreelevelcontribution and resonancecontribution (Stollenwerk, Hanhart, Kupsc, Meiner and Wirzba PLB707 (2012) 184-190) C. Di Donato - Rencontres de Moriond QCD
+- ++0 • TheoryHLS-Model: • ()w = (56.31.7) eV ()wo = (100.92.8) eV • ()= (604) eV[PDG] provide strong evidence in favourof BOX Anomaly Thisanalysis: L = 558 pb-1 2107 mesons (4.6% ) 14 C. Di Donato - Rencontres de Moriond QCD
, +- • 2 clusters: |tcl-lcl/c|<5 • 2 Tracksclosestto IP • 1 clusters: E >250 MeV • Two body decaysconstrain E • Kinematicfromdecaysconstrain • Main background+-0 • BKG feature: in the0rest frame are back to back ( < 165°) • TOF toreject e+e- background Events/4 MeV M • Signal in M +-window (539.5÷554.5) MeV C. Di Donato - Rencontres de Moriond QCD
+- Data sample L =558 pb-1 Ng =204 950 =(21.310.04)%; B/S=10% Signalcountingfrom fitto E-P C. Di Donato - Rencontres de Moriond QCD
Composition Normalization Sample: +- 0 • • L =558 pb-1 • N =1´190103 • =(22.770.02)%; • B/S=0.65% • e+e- • =41.8 0.2 nb BR() = (22.41 0.03 0.35)% (systematics include: 0.5% (lumy)1%(x-sec.) 1% (evcl) 0,43% (cut analysis) = 1.56% ) PDG’10:BR() = (22.74 0.28)% C. Di Donato - Rencontres de Moriond QCD
+- ++0 • Measurementhasbeenperformed on L=558pb-1 • N=204´950 and N= 1´190´000 • Systematics at levelof 1.5% • TheoryHLS-Model: • ()w = (56.31.7) eV ()wo = (100.92.8) eV • ()= (604) eV[PDG] C. Di Donato - Rencontres de Moriond QCD
+- d/dM • FitwithModelindependentmethodbased on ChPT and dispersive analysis: (Stollenwerk, Hanhart, Kupsc, Meiner and Wirzba PLB707 (2012) 184-190) C. Di Donato - Rencontres de Moriond QCD
Dipion Invariant Mass PLB707 (2012) C. Di Donato - Rencontres de Moriond QCD
Dipion Invariant Mass NTeo (taking into account efficiency and smearing) Ndata PRELIMINARY [WASA Coll. PLB707 (2012) 243-249] C. Di Donato - Rencontres de Moriond QCD
DAFNE-Upgrade DANE upgrade -New interaction scheme: large beam crossing angle + sextupoles for crab waist • Luminosity increase: factor ~ 3; Ldt 1 pb-1/hour New scheme Old scheme C. Di Donato - Rencontres de Moriond QCD
KLOE Upgrade Inner Tracker: 4 layers of cylindrical triple GEM Minimal detector upgrade for first KLOE-2 run (≈5 fb-1 in 1 year): taggers to detect momentum of leptons ine+e-→e+e-g*g*→e+e-X Q-CALT/C-CALT: Increase acceptance for ’s from IP (21°→10°) C. Di Donato - Rencontres de Moriond QCD
Conclusions • High statistic samples of light mesons produced @KLOE allowed to perform precision measurement and to look for very rare decays • Analysis on full KLOE data set: • f → hU,h →p+p-p0 [PLB706 (2012) 251-255] • h → p+p-g [Preliminary in arXiv: 1107.5733 hep-ex] • gg → h/gg → p0p0[arXiv: 1107.3782 hep-ex] • e+e- taggers in KLOE-2 • p+p-g/m+m-g • New data taking@KLOE-2 in 2012: notstablerunningyet C. Di Donato - Rencontres de Moriond QCD
SPARE C. Di Donato - Rencontres de Moriond QCD
PLB706 (2012) 251-255 e+ e- , with +-0 BR(e+e-)=1.15 10-4 : producedevents 106 e+e- Ks KL peak C. Di Donato - Rencontres de Moriond QCD
PLB706 (2012) 251-255 e+ e- , with +-0 • Wehave 14000 candidates: e+e-with+ - 0 • Verysmallresidualcontaminationfrom • MC Meeshapefrom VMD with FF slopefrom SND (213 events) [PLB504 (2001) 275] • Background extracteddirectlyfrom data C. Di Donato - Rencontres de Moriond QCD
X Physics: Weizsäcker-Williams approx, |q2| << W2 Tagger is essential to reduce bckg from f and to close kinematics KLOE-2 Lint = 1 fb-1
Fusion @KLOE without tagger C. Di Donato - Rencontres de Moriond QCD
Fusion C. Di Donato - Rencontres de Moriond QCD
Fusion C. Di Donato - Rencontres de Moriond QCD
Fusion: @KLOE without tagger PRELIMINARY • 240 pb-1 @ s = 1 GeV • 8090 eventsafterselections • Bkgnormalizedusingx-sections KSKL ωπ0 f0γ