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Clean Prediction of K S K S , K L K L Production Rates in Vector Quarkonium Decay to K 0 K 0 PRL 96, 192001 (2006). Haibo Li Institute of High Energy Physics, Beijing . International Workshop on Heavy Quarkonium QWG4 – June 27-30 2006, BNL, USA. CP Violation (Im[...] 0).
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Clean Prediction of KSKS, KLKL Production RatesinVectorQuarkonium Decay to K0K0PRL 96, 192001 (2006) Haibo Li Institute of High Energy Physics, Beijing. International Workshop on Heavy Quarkonium QWG4 – June 27-30 2006, BNL, USA Haibo Li
CP Violation (Im[...] 0) CPV Established in Both K and B Decays d s b u c t Results on the CKM angles: Search for CPV in various reactions, probe possible new source of CPV. I am going to talk about possible CP observation in quarkonium decays which may be correlated with K, D, and B system . Haibo Li
VectorQuarkonium Decay to K0K0 System Strong EM Weak 10-9 K0 K0 K0 Q W K0 K0 K0 Q Assume QQ is pure QQ system, the possible strong multiquark effects that involve seaquarks play no rule here. The K0K0 system is in a state with charge parity C = -1: The reason is that the relative orbital angular momentum of the K0K0 pair must be in L = 1 because of angular momentum conservation. A boson-pair with L = 1 must be in an antisymmetric state, the antisymmetric state of particle-antiparticle pair must be in a state C = -1: Haibo Li
CPV Processes 1--Quarkonium Decay to KSKS , KLKL Within Standard Model, the possible CPV processes Vector QQbar KSKS, KLKL are due to K0K0 oscillation! KSKL KLKS KSKS KLKL K0 K0 t1 t0 t2 CPV processes Time evolution of the K0K0 system produced in vector QQ decay can tell us the possibilities to find KSKL, KLKS, KSKS and KLKL Haibo Li
TimeEvolution of K0K0 System The weak eigenstates of the K0 are: with eigenvalues : Following the 1-- Quarkonium decay, the K0 and K0 will go separately and the time evolution of the particle states is: Then the time evolution of K0K0 system : Haibo Li
Since the states <KS| and |KL> are unorthogonal, we have : Time Dependent Amplitudes Then the amplitudes to find KSKS, KSKL, KLKS, KLKL pairs are: A1(t1, t2) = A4(t1, t2) A2(t1,t2) = -A2 (t2,t1) If CP is conserved, |p/q|=1, or the two particles are observed at the same time, namely, t1=t2, then A1(t1, t2) = A4(t1, t2)=0 for KSKSand KLKLcases because Bose-Einstein statistics prevents two identical bosons from being in an antisymmetric state. In other words, only KS and KL can be see at the same time in 1-- K0K0 decay. Haibo Li
Time-integrated Possibilities The time integrated possibilities to observe KSKS, KSKL and KLKL pairs, which are normalized by the widths of KS and KL are: Haibo Li
The Decay Widths The Partial widths of the KSKS, KLKL, KSKL are: where C is the phase space factor. The ratio RSS and RLL are defined as: In the ratios, the phase space factor C and the strong matrix element square are completely canceled, which insure that the ratios are completely free from uncertainty caused by strong interaction in the decay. Haibo Li
Correlation with KL Semileptonic Decays RSS and RLL can be determined by using experimental measured Values of x, y and |p|2 - |q|2, where |p|2 - |q|2 is related to CP asymmetry parameters L in semileptonic KL decay: Haibo Li
The Predicated Results for RSS and RLL From PDG 2004, one gets: = (0.327 0.012)% 8% relative error! The results can be extended to all 1-- heavy quarkonia: Haibo Li
Current Experimental Status for KSKL BES: 14M, (2S)KSKL PRL, 92, 052001(2004) BES: 58M, J/ KSKL PRD, 69, 012003(2004) Haibo Li
The Predicted Results for CPV QQ(1--) KSKS Processes BESII: PRD 69, 012003 (2004) BESII: PRL, 92, 052001 (2004) From PDG 2004 We gotthe following predicted branching factions for CPV processes : Haibo Li
BESII 58M J/ , J/ KSKS Search for CPV QQ(1--) KSKS Processes (1) BESII: PLB 589 (2004) 7 BESII 14M (2S), (2S) KSKS The main backgrounds are due to J/ gKSKS which will dilute the CP of KSKS final states. At BESIII, 1010 J/ sample can be produced per year ! Haibo Li
Search for CPV QQ(1--) KSKS Processes (2) 2.3 fb-1 data collected at peak at DA NE, which correspond to 6 109 decay events. These data can be used to probe KSKS and KLKL precisely with statistic error about 1% level according to the prediction Br( KSKS ) = (3.59 0.27)10-6 The precise RSS will be obtained at 1% level, then, it can be used to constrain the KL semileptonic decay parameter L [ 4% 1%] by using the correlation between KSKS decay and KL semileptonic decay . (nS) KSKS will be reached at future Super-B factory. Haibo Li
One has to take care of the possibility of neutral K regeneration in detectors (KLOE, BES-III, Super-Belle). The beam pipe or material in Draft Chamber will be the target to make K regeneration. In this case, KSKL final states may become KSKS or KLKL, which will dilute the CP measurements. Especially, it is more dangerous at phi factory since the momentum of K is very low. Background from K Regeneration --Dissipation and Decoherence We are working on this possible dilution at BES-III. Haibo Li
Isospin Relation in QQ(1--) KK Decays Because of isospin symmetry, we have then, it is straightforward to obtain the following relation by neglecting the phase space difference: Where A is the correction factor due to K0-K0bar mixing: One get A is notexactly equal to 1, even isospin symmetry is an exact symmetry : One has to consider K0 mixing effect when test isospin symmetry which is violated mostly due to Electromagnetic effects. Haibo Li
Summary(1) • We have studied the CPV decay processes of J/, (2S), and (nS) • Quarkonia to KSKS and KLKL. • The ratio of RSS (RLL) of KSKS (KLKL and KSKL production rates has • been constructed in a model-independent way: • Simultaneous measurements of vector quarkonium decays to both KSKS • and KSKL pairs are suggested at higher luminosity e+e- machines (BEPC-II, • DA NE-II, and Super-B). So many systematic errors can be canceled in the • ratio RSS measurements. Haibo Li
Summary(2) • With current experimental information, the absolute branching fractions • of the CPV processes are first predicted: The results had been published at Phys. Rev. Lett. 96 (2006) 192001 By Haibo Li and Mao-Zhi Yang Haibo Li