1. 1 Analysis of B->J/  K* 1. Overview of B->J/  K* physics 2. My analysis status 3. Future plan Niigata Univ. / Yoshiyuki Onuki i. Physics Motivation ii. Helicity states of General B->V a V b decay modes iii. Helicity states of J/  K* and angle definitions iv. Angle dependent v. Past results i. Analysis method ii. Selection criteria iii. Reconstruction Outline

2. Overview of B->J/  K* physics

3. Physics Motivation  (B->f ) -  (B->f )  (B->f ) +  (B->f ) pQCD factirization hypothesis test cos2   can be measured in Indirect CPV. => sin2   = sin(  -2   ) ambiguity is solved by cos2  . Direct CPV can be occurred if new physics existed. a dir ≡ To achieve these motivations, we need Angular analysis Small systematic error analysis Br(B->J/  Br(B 0 → J/  K* 0 ) = (1.29  × 10 -3 Belle 29.4fb -1 Official results

4. Helicity states and Angle definition J/  K* B (  )  3 helicity states B-> J/  K*has B-> J/  K* ( b1, b2 ) = (0,0) l1l1 l2l2 K  l2l2 l1l1 l2l2 l1l1 or K  × ( b1, b2 ) = ( ± 1/2, ∓ 1/2) and has 2 helicity states. J/  -> l + l -, K*->K  z x y

5. Amplitudes and angle dependence Decay width  depends on (  ,  ) 3 helicity states B->V a V b 2 helicity states J/  K* A┴A┴ A║A║ A0A0 A (+1) A (- 1) A (+1) = A ┴ g ┴ (+1) +A ║ g ║ (+1) + A 0 g 0 (+1) A (-1) = A ┴ g ┴ (-1) + A ║ g ║ (-1) + A 0 g 0 (-1) Incoherent  (  ,  ) = |A (+1) | 2 + |A (-1) | 2 g  (  ,  ) depends only on angles

6. Status of my analysis

7. PID likelihood is calculated by detector information. we use it. daughter  energy>40MeV e ,  ,  K ,     Particle reconstruction ss 0.47 [GeV/c 2 ] 0.52 K s 0.47<M(     )<0.52 [GeV/c 2 ] B 0 ->J/  K*(K +   ) B + ->J/  K*(K s   ) B + ->J/  K*(K +   ) B 0 ->J/  K*(K s   ) We want to reconstruct these decay modes

8. Reconstruction of K *, J/  J/  (  ) J/  (ee) [GeV/c 2 ] 0.8170.967  2.953.153.053.15 J/  (ee) J/  (  ) 2.95<M(ee)<3.15[GeV/c 2 ] 3.05<M(  )<3.15[GeV/c 2 ] K* 0.817<M(K  )<0.967 [GeV/c 2 ]

9. Reconstruction of B [GeV/c 2 ] [GeV] Signal Box 5.27<M bc <5.29 -0.03<dE<0.03 -0.05<dE<0.03 For   including mode B->J/  K*(K +   ) 30.8% B->J/  K*(K s   ) 21.9% B->J/  K*(K +   ) 13.9% B->J/  K*(K s   ) 8.8% Detection efficiency # Generate event #signal event ≡ Very rough estimation Each value is calculated with Signal MC 1.0 Million. 5.2<M bc <5.29[GeV/c 2 ] && -0.2<dE<0.2[GeV] B candidate 5.295.27 -0.030.03

10. Signal yield extraction To extract the signal yields, we will use unbinned maximum likelihood method. Statistics Error ≲ Systematic Error We must make more precise fit function to extract signal yield.  Precise BG study  More improved fit method This study is my current task.

11. Improved PDF function PDF(  M bc ) =N × [f sig (M bc ) ×  (  ) × d 3  d  d  d  ) +   f cf  (M bc ) × ADF cf (  ) +f nr (M bc ) × ADF nr (  ) +f combi (M bc ) × ADF combi (  )] f cf  f nr f combi cross feed BG( contamination from other J/  K* ) Non-resonant BG(J/  K  ) Combinatrial BG. ADF Angle distribution function  Detection efficiency N normalization factor … … … … … … The probability density function (PDF) is difined as Dominant in amplitude mesurement Dominant in Br mesurement

12. Status & future plan I want to extract Br(B->J/  K*) until JPS presentation ~ 3/28 Studying amount and shape of feed across contaminations. Current study Future plan To do Feed across,non-resonant,combinatorial BG estimation. => determine the shape using large amount of MC.

13. Back-up slides

14. Mixing and Decay process B 0 B 0 mixing Bf B Mixing Decay  Helicity states Time dependent Time dependent Decay amplitude where Decay amplitude

15. cos2  

16. Imaginary Phase = V * tb V td V cs V * cd V cb V * cs V tb V * td V * cs V cd V * cb V cs ( ) ()() = =   V td V * tb -V td V * tb V cd V * cb ( ) *  =   e -2i       b d c c d s J/  K*

17. Helicity states of General B->V a V b decay mode V …Vector Meson( spin 1, Parity +) (V a V b ) = J/  K*, D*  J,M=0  a b ) =(+1,+1),(-1,-1),(0,0) has 3 helicity states B-> J/  K*  Helicity J/  K*

18. Past measurements Belle 29.4fb -1 Official results Br(B 0 → J/  K* 0 ) = (1.29  × 10 -3 Br(B + → J/  K* + ) = (1.28  × 10 -3 |A ┴ | 2 = 0.19  |A 0 | 2 = 0.62  arg(A ┴ ) = 2.83  arg(A 0 ) = -0.09  Update for 140fb -1 Reduce the systematic error sin2  1 = 0.13  ( 78fb -1 ) cos2  1 = 1.40  } Phys.Lett.B538(2002) My study is also