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New Resonances at Belle B. Golob University of Ljubljana, Slovenia Belle Collaboration B. Golob, Belle Cracow Epiphany Conference, 2005 Experimental environment.

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Presentation on theme: "New Resonances at Belle B. Golob University of Ljubljana, Slovenia Belle Collaboration B. Golob, Belle Cracow Epiphany Conference, 2005 Experimental environment."— Presentation transcript:

1 New Resonances at Belle B. Golob University of Ljubljana, Slovenia Belle Collaboration B. Golob, Belle Cracow Epiphany Conference, 2005 Experimental environment D sJ ’s and their properties X(3872)......and also Y(3940) cc recoil spectrum pentaquarks? Conclusion

2 B. Golob, Belle Cracow Epiphany Conference, 2005 Experimental environment KEKB asymmetric B factory ~1 km in diameter Mt. Tsukuba KEKB Belle Υ(4s) e+e+ e-e- B B ∫Ldt = 255 fb -1 on reson. 30 fb -1 off reson. ~280 M BB > 900 pb -1 /day (~1 M BB/day) Integrated luminosity May ‘99 Oct ‘04

3 B. Golob, Belle Cracow Epiphany Conference, 2005 Experimental environment combined particle ID  (K ± )~85%  (  ± →K ± p<3.5 GeV/c 3(4) layer Si vtx det. Central Drift Chamber  (p t )/p t = 0.3% √p t 2 +1 Aerogel Cherenkov Counter (n= ) 1.5T SC solenoid e - 8 GeV e GeV EM Calorimeter CsI (16X 0 )  and K L identification (14/15 lyrs RPC+Fe)

4 B. Golob, Belle Cracow Epiphany Conference, 2005 Experimental environment e+e+ E CM /2 e-e-  (4s) B B ∑ p i, ∑ E i signal Off reson. data: continuum only On reson. data: BB (spherical) separated from continuum (jet shaped) on basis of topological variables e.g. angle between B direction and beam axis B continuum

5 B. Golob, Belle Cracow Epiphany Conference, 2005 D sJ states Production in continuum D sJ * (2317) + → D s +  0 D sJ + (2460) → D s *+  0 D sJ + (2460) → D s +  Mass (GeV) Ds+Ds+ D s *+ Masses lower than predicted in potential models; Widths consistent with zero 86.9 fb -1,PRL92,012002(2004) M(D sJ (2317))= ± 0.5 ± 0.9 MeV M(D sJ (2460))= ± 1.3 ± 1.3 MeV

6 B. Golob, Belle Cracow Epiphany Conference, 2005 D sJ states Production in B decays D sJ * (2317) + → D s +  0 D sJ (2460) + → D s *+  0 D sJ (2460) + → D s +  D sJ * (2317) + → D s +  0 D sJ (2460) + → D s +  J=1 J=0 J=1 J=2 275M BB,BELLE-CONF-0461 Data agree with J P =0 + (D sJ (2317)) and 1 + (D sJ (2460)) Br(B 0 →D - D sJ * (2317) + )=(10.3±2.2±3.1)x10 -4 Helicity angle:  DsDs ,0,0 D B D sJ B → D D sJ

7 B. Golob, Belle Cracow Epiphany Conference, 2005 D sJ states D sJ * (2317) - → D s -  0 (D s → ,K*K,K S K) (GeV) 152M BB,hep-ex/ (GeV) EE M(D s  0 )-M(D s ) 6.8  signif. First observation of B 0 → D sJ *- K + Br(B 0 → D sJ (2317) - K + )∙ Br(D sJ (2317) - → D s -  0 )= (5.3 ± 1.4 ± 0.7 ± 1.4)x10 -5 B → D sJ (2317)  - B → D sJ (2460)K + B → D sJ (2460)  - <2.5x10 CL <0.94x10 -5 <0.40x10 -5 Br(B 0 → D sJ * (2317) - K + )∙Br(D sJ * (2317) - → D s -  0 ) Br(B 0 → D s - K + ) = 1.8 ± 0.6 Br(B 0 → D - D sJ * (2317) + )∙Br(D sJ * (2317) + → D s +  0 ) Br(B 0 →D - D s + ) = 0.13 ± 0.05 b d B0B0 W u s c s D sJ K+K+ d d 4-quark content?

8 B. Golob, Belle Cracow Epiphany Conference, 2005 X(3872) Observed by Belle with 152M BB B ± → K ±  +  - J/  l+l-l+l- 152M BB, PRL91, (2003) How about with 275M BB? Calculate M bc in 5 MeV bins of M(  +  - J/  ) 3865 MeV 3870 MeV 3875 MeV 48.6±7.8 evts. (>10  ) M= ±0.7 MeV M(  +  - l + l - )-M(l + l - ) M(  +  - l + l - ) 275M BB,S.Olsen,GHP’04 no. of B’s in bins of M(  +  - J/  )

9 M bc B. Golob, Belle Cracow Epiphany Conference, 2005 X(3872) B ± → K ±  +  -  0 J/  EE M bc and  E in 25 MeV bins of M(  +  -  0 ) consistent with ±4.2 evts.(6.4  ) M(  +  -  0 )>750 MeV First observation of decay mode other than  +  - J/  ; subthreshold decay to  J/y (expected for DD* molecule) M(  +  -  0 J/  )= M(X)± 3  C(X(3872))=+1 no. of B’s in bins of M(  +  -   )

10 B. Golob, Belle Cracow Epiphany Conference, 2005 Y(3940) B → K  +  -  0 J/  Events in  E, M bc signal region M(  +  -  0 J/  ) M(  +  -  0 ) B → K  J/  M 2 (J/   ) M 2 (K  ) Dalitz plot for B → K  J/  B ± → K * J/  K *  → K ±  For these B → K  J/  plot M bc,  E in bins of M(  J/  ) resonant structure?

11 B. Golob, Belle Cracow Epiphany Conference, 2005 Y(3940) B ± → K ±  J/  Relatively large signal at low M(  J/  ) No. of B’s in bins of M(  J/  ) large deviations from phase space 3897 MeV 3937 MeV 3977 MeV 40 MeV bins M(  J/  ) Fit with added BW (8.1  ) M(Y)=3943±11±13 MeV  =87±22±26 MeV 58 ± 11 evts. Br(B → YK)Br(Y →  J/  )= (7.1±1.3±3.1)x M BB, hep-ex/

12 B. Golob, Belle Cracow Epiphany Conference, 2005 well established method(e.g. double cc production) J/  X e-e- e+e+ Reconstruct J/  →  l + l - Calculate recoil mass (mass of X): cc recoil spectrum confirmation of  c (2s) after 1st observation by Belle cc  c0  c (2s) 285 fb -1,T.Ziegler,GHP’04 N=148 ± 33 (4.5  ) M=3940 ± 11 MeV new resonance Reconstruction of additional D or D* beside J/  → - new resonance decays to DD * ; - not seen in J/  probably not Y(3940)

13 B. Golob, Belle Cracow Epiphany Conference, 2005 Pentaquark searches select pK secondary vtx detector “tomography”: x[cm] y[cm] M(pK - ) M(pK S )  (1520) M(pK - )fit with D-wave BW and treshold funct.;  parameters in agreement with PDG M(pK S ) fit with 3rd order poly.and narrow sig.(2 MeV) at different m assuming Br(  + → pK S )=25% 155M BB,hep-ex/ Searches in decays,“high energy” (charm baryon,B) Searches in secondary interactions,“low energy”  (KN   + (1540)X)  (KN   (1520)X) < 2%(90%CL)

14 B. Golob, Belle Cracow Epiphany Conference, 2005 Pentaquark searches B decays B 0  p pK S B +  p pK +  (1540) +  * (1600) ++ c0c0  c *+ B 0  p  + D ( * )- p M(  c 0 )=3099 MeV(H1)  =3.5 MeV (det. resol.) B 0  p D 0 CL 155M BB,hep-ex/ B 0  p  + D - p 303 ±21 evts.

15 B. Golob, Belle Cracow Epiphany Conference, 2005 Conclusions  KEKB is also a great source of charm& cc states  Some expected, mainly unexpected/puzzling observations/discoveries understanding range of questions: what are they? why such properties? all properties as expected? will be addressed as more statistics is collected D sJ properties BELLE-CONF-0461 hep-ex/ X(3872) →  J/  S.Olsen,GHP’04 Y(3940) hep-ex/ resonance in cc recoil T.Ziegler,GHP’04  c (2s) PRL89, PRD70,  c (2800) hep-ex/ D ** broad states PRD69,  c + p structure hep-ex/ PQ searches hep-ex/

16 new stateproductiondecay modeto establish next reference D sJ Continuum B → DD sJ, B → D sJ K D s  0, D s *  0, D s  Br’sBELLE-CONF-0461 hep-ex/ X(3872)B → KX  +  - J/   +  -  0 (  ) J/  quantum num., decay modes hep-ex/ S.Olsen,GHP’04 Y(3940)B → KY  J/  M,  hep-ex/ X(3940)continuum, cc recoil M recoil,DD * M,  T.Ziegler,GHP’04  c (2s) continuum, cc recoil M recoil  PRD(R)70,  c (2800) continuum c+c+ ,  (mixing) hep-ex/ broad D ** B + → D **  + D (*)  Br’sPRD69,  c + pB - →  c + p  - M(  c + p )M,  hep-ex/  + (1540) sec. int. pKpK S existence?hep-ex/  +,  *++,  c 0,  c *+ B decayspK S,pK +, D ( * )- p,D 0 p existence?hep-ex/  +,  *++,  3/2 --,  3/2 + charm baryon decays pK S,pK +,  -  -,  -  +  + existence?

17 PQ backup

18 B. Golob, Belle Cracow Epiphany Conference, 2005 Pentaquark searches backup slide Searches in decays,“high energy” charm baryon decays, B decays Searches in secondary inter.,“low energy” charm baryon decays  c + → p K s K s c+c+  (1540) + M(pK S K S ) M(pK S )  c + → pK + K - M(pK + K - )  * (1600) ++ M(pK + )  (1670) fb -1

19 B. Golob, Belle Cracow Epiphany Conference, 2005 Pentaquark searches backup slide  c 0 →  -  -  +  +  3/2 (1862) -- M(  -  -  +  + ) M(  -  - ) M(  -  +  + )  3/2 (2320) + charm baryon decays

20 B. Golob, Belle Cracow Epiphany Conference, 2005 Pentaquark searches backup slide Searches in sec. inter. select pK secondary vtx detector “tomography”: x[cm] y[cm] M(pK - ) M(pK S )  (1520) M(pK - )fit with D-wave BW and treshold funct.;  parameters in agreement with PDG M(pK S ) fit with 3rd order poly. and narrow sig. (2 MeV) at different m  (1540) +  (KN   + (1540)X)  (KN   (1520)X) < CL assuming Br(  + → pK S )=25% m 155M BB,hep-ex/

21 B. Golob, Belle Cracow Epiphany Conference, 2005 Pentaquark searches backup slide  (1520) spectrum p (fit to M(pK - ) in mom. bins p K-K- K-K- p  (1520) formation p(pK - )~500 MeV p K-K- K-K- p  (1520) production majority formation distance pK - vtx – next track distance pK - vtx – next K + vtx with addit. track non-zero strangeness most pK vtx produced by strange particles cm  (KN   + (1540)X)  (KN   (1520)X) < 2%(90%CL) assuming Br(  + → pK S )=25% Br(  (1520) → pK - )= 0.5 Br(  (1520)X → NK) ratio of  from MC

22 D sJ backup

23 B. Golob, Belle Cracow Epiphany Conference, 2005 D sJ states Production in continuum backup slide reconstruction: D s →  → K + K - D s * → D s  p(D sJ )>3.5 GeV D sJ + (2317) → D s +  0 D s side band  0 side band D s *+ (2112) also D s + (2460) → D s *+  0 ;  lost (MC) D sJ + (2460) → D s *+  0 D s * side band D s + (2317) → D s +  0 +random  D sJ + (2460) → D s +  D s side band M(D sJ (2317))= ± 0.5 ± 0.9 MeV M(D sJ (2460))= ± 1.3 ± 1.3 MeV  (D sJ (2317))<4.6 CL  (D sJ (2460))<5.5 CL Br(D sJ (2460) → D s +  )/Br(D sJ (2460) → D s *+  0 )=0.55±0.13±0.08

24 B. Golob, Belle Cracow Epiphany Conference, 2005 D sJ states Production in B decays D sJ + (2317) → D s +  0 D sJ + (2460) → D s *+  0 D sJ + (2460) → D s +  B (0,±) → D (0,±) D sJ backup slide M(D sJ ) side band  E side band All events in M bc signal region Reconstruction D 0 → K +  -,K +  -  -  +,K +  -  0 ; D - → K +  -  - Masses: ±1.1±2.0 and ±0.9±2.0 MeV;

25 B. Golob, Belle Cracow Epiphany Conference, 2005 D sJ states Production in B decays B (0,±) → D *(0,±) D sJ backup slide M(D sJ ) side band  E side band All events in M bc signal region D sJ + (2317) → D s +  0 D sJ + (2460) → D s *+  0 D sJ + (2460) → D s + 

26 B. Golob, Belle Cracow Epiphany Conference, 2005 D sJ states Production in B decays backup slide B  D D sJ (2317) [D s  0 ] 10.1  1.5   B  D D sJ (2317) [D s *  ] (<8.4) 3.5  B  D D sJ (2460) [D s *  0 ]   B  D D sJ (2460) [D s  ] 6.4  0.8   B  D D sJ (2460) [D s *  ] (<5.7) 3.0  B  D D sJ (2460) [D s  +  -] (<2.3) 2.6  B  D D sJ (2460) [D s  0 ] (<1.7) -- B  D* D sJ (2317) [D s  0 ] (<8.5) 2.0  B  D* D sJ (2460) [D s *  0 ]   B  D* D sJ (2460) [D s  ]   Decay channel Br[10 -4 ] signif. Largest syst. uncertainty from  0 eff. and D branching fractions Br’s from  E fits in M bc and M(D sJ ) signal region Br(D sJ (2460) → D s +  )/Br(D sJ (2460) → D s *+  0 )=0.43±0.08±0.04

27 B. Golob, Belle Cracow Epiphany Conference, 2005 D sJ states First observation of B 0 → D sJ + K - backup slide W exchange FSI tree,4 quark content D sJ (2317) K - D sJ (2317)  + D sJ (2460) K - D sJ (2460)  ±4.4 evts.

28 B. Golob, Belle Cracow Epiphany Conference, 2005 D sJ states First observation of B 0 → D sJ + K - backup slide Br from fit to M(D s  0 )-M(D s ) in signal region of  E and M bc Width fixed from MC, peak position allowed to float Cross checks: Br obtained by fits to  E or M bc in good agreement; Width and peak position allowed to float – good agreement with MC; Random combinations of true D sJ and K checked by  E and M bc side bands – less than 1 event expected; Main cont. to syst. uncertainty  0,  eff.; D sJ and K combinatorics  2 =1.44  2 =4.72

29 B. Golob, Belle Cracow Epiphany Conference, 2005 D sJ states backup slide B. Golob, Belle Cracow Epiphany Conference, 2005 First observation of B 0 → D sJ + K - Br(B 0 → D sJ (2317) + K - )x Br(D sJ (2317) + → D s +  0 )= ( ± 0.7 ± 1.4)x10 -5 No significant signal observed in B → D sJ (2317)  - B → D sJ (2460)K + B → D sJ (2460)  - (D sJ (2460) → D s  <2.5x10 -5 <0.94x10 -5 <0.40x10 CL Br(B 0 → D s + K - )=(2.93±0.55±0.79)x10 -5 Br(B 0 → D sJ (2317) + K - ) of same order; Br(B 0 → D sJ (2460) + K - ) twice smaller (assuming Br(D sJ (2460) → D s  )~30%) Br(B 0 → D sJ (2317) + K - )∙ Br(D sJ (2317) + → D s +  0 )=(5.3 ± 1.4 ± 0.7 ± 1.4)x10 -5 Br(B 0 → D s + K - )=(2.93 ± 0.55 ± 0.79)x10 -5 Br(B→D - D sJ + (2317))∙Br(D sJ (2317) + → D s +  0 )=(10.3 ± 2.2 ± 1.7 ± 2.6)x10 -4 Br(B→D - D s + )= (8.0 ± 2.2 ± 2.0)x10 -5 uncertainty due to D s Br’s; cancels in the ratio

30 D** backup

31 B. Golob, Belle Cracow Epiphany Conference, 2005 D ** states backup slide Potential model prediction for cu: B+→D-++B+→D-++ B + → D *-  +  + Modes used: D 0 → K -  +, K -  +  +  - D + → K -  +  + D *+ → D 0  + ~1100 evts. ~550 evts. Dalitz plot analysis D side band D 0 *, D 1 ’ broad states D 1, D 2 * narrow states 65M BB,PRD69,112002

32 B. Golob, Belle Cracow Epiphany Conference, 2005 D ** states backup slide B+→D-++B+→D-++ B + → D *-  +  + M(D  ) max M(D  ) min  E side band bckg. subtracted D0*D0* D2*D2* D v *,B v * D1’D1’ D2*D2* D1D1 proj. of 2D fit proj. of 4D fit

33 B. Golob, Belle Cracow Epiphany Conference, 2005 D ** states backup slide Unbinned max. lik. fit to Dalitz plot; bckg. from  E side band Dalitz plot; D 1 or D 1 ’ (J P =1 + ) cannot contribute to D  in D  final state; signal described as D 0 * (J P =0 + ) + D 2 * (J P =2 + ) + virtual D v * or B v * + constant (non-resonant) term M(D *+ ) < M(D +  - ) → virtual D v * similarly B → B v * , B v * → D  inclusion of D v *, B v * significantly improves the fit negligible contribution Each state relativistic BW, q 2 dependent , specific ang. dependence (angle between  from B and  from D ** in D ** frame; Blatt-Weiskopf param. of B → D **, D ** → D form factors; D ** resonance parameters, amplitudes and relative phases free param. of fit Fit to D  distrib.:

34 B. Golob, Belle Cracow Epiphany Conference, 2005 D ** states backup slide M(D 0 * )= 2308±17±15±28 MeV;  (D 0 * )= 276±21±18±60 MeV; M(D 2 * )= ±2.1±0.5±3.3 MeV;  (D 2 * )=45.6±4.4±6.5±1.6 MeV; larger than WA (23±5 MeV), but no interf. effects taken into account; Focus exp. 30.5±4.2 MeV hep-ex/ errors: stat. syst. model varying selection; track, PID eff.; fits with D v *,B v *,constant = 0 for default fit = if no D 0 * or J P =1 -,2 + Br(B - → D 0 *  - )Br(D 0 * → D +  - )=(6.1±0.6±0.9±1.6)x10 -4

35 B. Golob, Belle Cracow Epiphany Conference, 2005 D ** states backup slide Unbinned max. lik. fit in 4D space; bckg. from  E side band Dalitz plot; D 0 * (J P =0 + ) cannot contribute to D *  in D *  final state; signal described as D 1 (J P =1 + ) + D 2 * (J P =2 + ) + D 1 ’(J P =1 + ) virtual D v * or B v * + constant (non-resonant) term; D 2 * parameters fixed to values from D  final state Since D * vector, two more angles for final state descr.; angle between  from D ** and D *, angle between  from D * and B → D *  plane; additional mixing angle between J P =1 + states; Fit to D *  distrib.:

36 B. Golob, Belle Cracow Epiphany Conference, 2005 D ** states backup slide M(D 1 ’)= 2427±26±20±15 MeV;  (D 1 ’)= 384±90±24±70 MeV; M(D 1 )= ±1.5±0.4±0.8 MeV;  (D 1 )=23.7±2.7±0.2±0.4 MeV; = 0 for default fit = if no D 1 ’ or J P =1 -,2 + in agreement with WA Br(B - → D 1 ’  - )Br(D 1 ’ → D* +  - )=(5.0±0.4±1.0±0.4)x10 -4 narrow reson. (D 1,D 2 * ) comprise 36±6% of D  final state 63±6% of D *  final state QCD sum rule: narrow reson. dominate D (*)  state LEP: B→D (*)  l also not dominated by narrow reson.

37 X(3872) backup

38 B. Golob, Belle Cracow Epiphany Conference, 2005 X(3872) backup slide c’c’ J/  cc  c0  c1  c2 ’’ ”” hchc c”c” hc’hc’  c1 ’  c2 22 33 2M D M D +M D* cc spectrum G parities:  c ” +1  c1 ’ +1  c2 +1 h c ’ -1  2 -1  3 -1  +  - J/  -1 G=(-1) L+S+I

39 M bc B. Golob, Belle Cracow Epiphany Conference, 2005 X(3872) backup slide Search for X →  c1  J/  M(  c1 ) ’’ X Width of 3 D 2 (  2 ) state to  c1 expected to be lager (factor 2-3) than to  +  - J/  Search for X →  c2  J/  B → KX M bc signal region M(  c2 ) in  ’ region M(  c2 ) in X region Width of 3 D 3 (  3 ) state to  c2 expected to be lager (factor at least 2) than to  +  - J/ 

40 B. Golob, Belle Cracow Epiphany Conference, 2005 X(3872) backup slide M(DD) in M bc and  E signal region 3 D 3 (  3 ) state could decay to DD through L=3 B ± → DDK ±  ’(3770) 2 3 P 1 state (  c1 ’) above DD * treshold; if below,  (  J/  ) probably larger than  (  +  - J/  ) B ± →  J/  K ± M(  J/  ) in  c1 region M(  J/  )in X region M bc 7.7±3.6 evts.

41 B. Golob, Belle Cracow Epiphany Conference, 2005 X(3872) backup slide Angular distrib. for 2 1 P 1 (h c ’) to  +  - J/  B X K J/  ++ --  expected for h c ’ X  2 /nof=75/9 |cos  |  c ” h c ’  c1 ’  2  c2  3 M too low;  too small  c should dominate  J/  angular dist’n rules out 1  M too low;  J/  too small  c   too small; m  wrong  c  & DD) too small; m  wrong X(3872) none of expected cc states M(  +  - ) in  +  - J/  close to  decay to  J/  ~ ½ of  +  - J/  arguments for DD* molecule interpret. E.S.Swanson,PLB588,189

42 B. Golob, Belle Cracow Epiphany Conference, 2005 X(3872) backup slide M(  ) for B→XK, X→  J/   E, M bc side band X → J/  (as indicated by m(  )) I(  )=1, I(  )=0, I(J/  )=0 → X decays break isospin symmetry ccuu=1/√2 cc [1/√2 (uu+dd)+1/√2 (uu-dd)] =1/√2(|I=0>+|I=1>)

43 B. Golob, Belle Cracow Epiphany Conference, 2005 X(3872) B ± → K ±  +  -  0 J/  M(  +  -  0 J/  ) M(  +  -  0 )  band X  band  E in 25 MeV bins of M(  +  -  0 ) Side regions B ± → K ±  J/  signal fit M bc and  E i ii iii iv v Possible contr. K ±  J/  0.75 ± 0.14

44 B. Golob, Belle Cracow Epiphany Conference, 2005 X(3872) B ± → K ±  +  -  0 J/  region I region III 4.3± ±5.6 non-resonant, peaking bckg. 1.3±1.0 (scaled to sig. area) backup slide B ± → K 1 (1270) J/  M(X)-M(3  ) signal region main syst. uncertainty: contrib. of peaking bckg. and K ±  J/  : -20%; M(3  )>750 MeV: +25% Simultaneous fit to  E and M bc distrib. for M(  +  -  0 )>750 MeV signific.: 6.4  (5.0  if 2 events peaking backg.)

45 Y(3940) backup

46 B. Golob, Belle Cracow Epiphany Conference, 2005 Y(3940) B → K  J/  |  E| < 0.03 GeV, < M bc < GeV all fits consistent yield within stat. error (~200±20) B yield in M(  J/  ) bins for B → K  J/  phase space MC  E in 40 MeV bins of M(  J/  ) Yields determined from simultaneous  E and M bc fits (constrained to be equal); peak position and width from fits to integrated distrib. backup slide Fit with f(M)=Aq*(M) q*(M): mom. of daughter part. in  J/  frame

47 B. Golob, Belle Cracow Epiphany Conference, 2005 Y(3940) B → K  J/  backup slide 20% variation included in syst. error. K s,K ± yields consistent with acc. ratio. K±K± KSKS M(K  ) M(  J/  )<3997 MeV (first 3 bins in M(  J/  )); no resonance in K  in this M(  J/  ) region M(  J/  ) acceptance M(  +  -  0 )  E, M bc signal region N  =74±14  E, M bc side band: N  =14±10(non-  3  ) fraction of true  in signal: 0.90 ± 0.18 (in syst. error)

48 B. Golob, Belle Cracow Epiphany Conference, 2005 Y(3940) B → K  J/  backup slide Main syst. uncertainty: fit using S-wave BW or Lorentzian shape for resonance; linear or 3rd order polynomial for bckg.; largest deviation +38% possible non-  3  contribution; -28% Significance: integral of fitted phase space in first 3 bins of M(  J/  ) 16.8±1.4 total number of events: 55.6 significance > 9  > 8 

49 cc recoil backup

50 B. Golob, Belle Cracow Epiphany Conference, 2005 J/  X e-e- e+e+ Reconstruct J/  →  l + l - Calculate recoil mass (mass of X): backup slide calibrate with e + e - →  (2S)   (2S) → J/  +  - <1% bckg. fitted with MC with free M rec 2 off-set  M 2 rec =0.010  GeV 2 /c 4 (data/MC); introduce momentum scale bias in MC to reproduce  M 2 rec Shift of M rec againts J/  with same momentum bias found  M rec (J/  ) < 3 MeV/c for M rec (J/  )  3 GeV/c cc recoil spectrum

51 B. Golob, Belle Cracow Epiphany Conference, 2005 Reconstruct J/  →  l + l - ; D 0 → K -  +,D + → K -  +  + backup slide J/  Y e-e- e+e+ D (*) ? Use events with M rec (J/  D)≈M(D*) Calculate M rec (J/  ) (mass of resonance decaying to DD (*) ) N=9.9  3.3 (4.5  ) N=4.1  2.2 (2.1  ) cc recoil spectrum

52 B. Golob, Belle Cracow Epiphany Conference, 2005 backup slide cc recoil spectrum B 0(±)  K S (±) (K S K ±  Ŧ ) M bc for 40 MeV M(K S K  )slices M(K S K  ) B yield  c (2s) N evt = 45.3±12.6 M  c’ = 3653 ± 10 MeV   c’ = 33 ± 22 MeV N evt = 90.5±14.9 M  c = 2978 ± 5 MeV   c = 33 ± 16 MeV cc  c (2s) direct reconstr. recoil M =  GeV N = 164  30

53 Isotriplet of charmed baryons backup

54 B. Golob, Belle Cracow Epiphany Conference, 2005 Isotriplet of charmed baryons  c  final state;  c → pK -  + M(pK -  + )  c (2880) + →  c +  +  - ++  c (2800) 0 M-M(  c )= ± MeV  c (2800) + M-M(  c )= – MeV  c (2800) ++ M-M(  c )= ± MeV  ~61-75 MeV 275M BB,hep-ex/ xpxp Peterson fragm. function  (e + e - →  c (2800)X)Br(  c (2800) →  c  = pb (± 1-2 pb) M(  c  )-M(  c ) 2.2x10 3 evts. 1.5x10 3 evts. 2.8x10 3 evts. c-c- c0c0 c+c+ States tentatively identified as  c2 (J P =3/2 -,  M~500 MeV);  ~15 MeV, mixing with  c1 ?

55 B. Golob, Belle Cracow Epiphany Conference, 2005 Isotriplet of charmed baryons  c  +  - final state: 4 excited charmed baryons lower two orbital excitations of  c + upper two ?  c  + final state:  c (2455) ground state  c (2520) spin excitation  c orbital excitations? c-c- c0c0 c+c+ side band Fit: D-wave BW + feed-down + comb. backg. backup slide feed-down  c + (2880) →  c +  +  - through  c (2455) 0,  c (2455) ++ feed-down not seen due to lower  (  0 ) Full recon. of  c + (2880) →  c +  +  - for signal events in bins of M(  c  )-M(  c ) to determine the amount of feed-down 2.24x x x10 3 x p >0.7

56 B. Golob, Belle Cracow Epiphany Conference, 2005 Isotriplet of charmed baryons backup slide M(  c  )-M(  c ) full region:  c (2455) 0  c (2520) 0 estimation of syst. uncertainty: - change of signal descr. (L=0,1) - change of comb. bckg. descr. - change of down-feed contrib. - change of x p and other selection criteria  c → pK -  +  c → pK S  c →  +  c (2800)/  c yield ratio cross-check:

57  c p structure backup

58 B. Golob, Belle Cracow Epiphany Conference, 2005  c + p structure 3-body baryon production in B decays: baryon-antibaryon system peaked near treshold B - →  c + p  -  c + → pK -  +,pK S,  +, pK S  +  -,  +  +  -  → p  - 264±20 evts.  c (2455) 0  c (2520) 0  (1600)  (2420) Fits to  E in mass bins BW peak + feed down from B - →  c +  M = 3.35 ± 0.02 GeV 50 ± 10 evts.(5.6  )  ~70 MeV 152M BB,hep-ex/

59 B. Golob, Belle Cracow Epiphany Conference, 2005  c + p structure  c (2455) 0 p  c +  (1232)  c +  (1600)  c +  (2420)  c + p simultaneous fit to 6  E distrib.; N i =  j  ij Y j Br(B - →  c (2455) 0 p)=( ± 0.36 ± 0.95)∙10 -5 Br(B - → (  c + p)  - )=( ± 0.43 ± 1.01)∙10 -5 due to Br(  c + → pK -  + ) M= ± 0.02 GeV  = ± 0.04 GeV from different bkgd. param.


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