V.Duk, INR Moscow Quarks-2008, May OKA Experiment for Studying Rare Kaon Decays Viacheslav Duk, INR Moscow for collaboration

V.Duk, INR Moscow Quarks-2008, May IHEP, Protvino OKA collaboration: IHEP, Protvino INR, Moscow JINR, Dubna

V.Duk, INR Moscow Quarks-2008, May Experiments with charged kaons 2.Separated kaon beam at IHEP 3.OKA physics program 4.Current status of the experiment 5.Conclusions Contents

V.Duk, INR Moscow Quarks-2008, May Current and future experiments with kaons In-flight decays Stopped kaons E06 – J-PARC,K+→μνπ 0 E09 – J-PARC, K+ →π + νν NA62 – CERN, K + (talk by Augusto Ceccucci) OKA - IHEP, Protvino, K ± (this talk) E14(KOTO) – J-PARC, K 0 (talk by Mikhail Doroshenko)

V.Duk, INR Moscow Quarks-2008, May Experiments with charged kaons Studying more rare decaysInreasing presicion High intensity beams Separated (“Clean”) beams NA62 OKA how experiment 2 strategies in kaon experiments Strategies are complementary

V.Duk, INR Moscow Quarks-2008, May Separated beams  Low background from inelastic scattering  Absence of trigger effects  Possibility of fixed target program  Complicated channel  Relatively low intensity + –

V.Duk, INR Moscow Quarks-2008, May separated and unseparated beams: complementarity NA62OKA beam Intensity ~10 9 5*10 6 Beam rate800 MHz1.1 MHz Kaons in the beam ~5%~70% Duty cycle30%22% % of kaons decaying in decay pipe 13%9% Kaon decay rate 520 x x 10 4

V.Duk, INR Moscow Quarks-2008, May RF separated beam at IHEP Panofsky scheme Deflectors: largest possible distance Synchronized em field (3GHz) in deflectors (-1) optics: pions are deflected in opposite directions Beam stopper: absorbe pions Choose momentum: maximal deflection of kaons Protons also absorbed (m p ) 2 /(m π ) 2 ~ 4 kaon deflection proton deflection Nd deflectors are cooled by liquid He, T=1.8K

V.Duk, INR Moscow Quarks-2008, May Physics program at OKA Baseline: ISTRA+ program on a larger statistics The program is being tuned by latest results from NA48/2, NA62, KLOE Main directionsmethod ChPT tests, deviations from SM BR and/or dalits-plot in Kl2,Kl2gamma, Kl3 decays T-odd effectsT-odd asymmetries in 4- body decays Sgoldstino searchK->π π 0 P decay: peak in (P K -P π -P π0 ) 2 distribution exoticaFixed target program ISTRA+: 3%(kaons)*2*10 6 =6*10 4 OKA: 70%(kaons)*5*10 6 =350*10 4 OKA / ISTRA+ ~60

V.Duk, INR Moscow Quarks-2008, May Physics: ChPT tests, deviations from SM Search for tensor and scalar terms K→μνπ 0 (Kμ3) and K→eνπ 0 (Ke3) decays a ISTRA+: ~500K Kμ3 OKA: ~20M Kμ3 Formafactors in Ke3, Kμ3, F v and F A in K→μνγ, K→eνγ

V.Duk, INR Moscow Quarks-2008, May Physics: T-odd effects

V.Duk, INR Moscow Quarks-2008, May Status of the experiment

V.Duk, INR Moscow Quarks-2008, May Status of the experiment

V.Duk, INR Moscow Quarks-2008, May Status of the experiment: separated beam Beamline with RF deflector RF deflector

V.Duk, INR Moscow Quarks-2008, May Status of the experiment: separated beam 1% 7% Kaons in the beam No separator with separator Separator status: commissioned Worked during 2007 test run Cleaning in progress

V.Duk, INR Moscow Quarks-2008, May OKA status: beam spectrometer Beam profile efficiency Beam proportional chambers: 1mm step 20cm X 20cm Threshold Cherenkov counters Beam magnet σP/P ~ 1%

V.Duk, INR Moscow Quarks-2008, May OKA status: active decay volume 11m long Filled with He sandwich veto counters with fiber readout (~300 channels)

V.Duk, INR Moscow Quarks-2008, May OKA status: spectrometer Straw tubes: 9mm tubes 2 layers 140cm x 140cm Drift tubes: 4cm tubes 3 layers 200cm x 200cm

V.Duk, INR Moscow Quarks-2008, May OKA status: electromagnetic calorimeter 3.8cm x 3.8cm cells Resolution 5%/√E ~20 X 0 ~4000 channels

V.Duk, INR Moscow Quarks-2008, May  RF separated high energy kaon beam at IHEP, Protvino has been constructed and is being commissioned  First stage of OKA setup has been commissioned  First statistics – November 2008 Conclusions

V.Duk, INR Moscow Quarks-2008, May

V.Duk, INR Moscow Quarks-2008, May Spares: separator

V.Duk, INR Moscow Quarks-2008, May Status of the experiment

V.Duk, INR Moscow Quarks-2008, May Status of the experiment

V.Duk, INR Moscow Quarks-2008, May Status of the experiment

V.Duk, INR Moscow Quarks-2008, May K→K→

V.Duk, INR Moscow Quarks-2008, May K→K→