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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 D sJ ’s and their properties X(3872)......and also Y(3940) cc recoil spectrum pentaquarks? Conclusion
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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
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B. Golob, Belle Cracow Epiphany Conference, 2005 Experimental environment combined particle ID (K ± )~85% ( ± →K ± )<~10% @ 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=1.015- 1.030) 1.5T SC solenoid e - 8 GeV e + 3.5 GeV EM Calorimeter CsI (16X 0 ) and K L identification (14/15 lyrs RPC+Fe)
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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
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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 + 1.8 2.2 2.6 3.0 3.4 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))=2317.2 ± 0.5 ± 0.9 MeV M(D sJ (2460))=2456.5 ± 1.3 ± 1.3 MeV
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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
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B. Golob, Belle Cracow Epiphany Conference, 2005 D sJ states D sJ * (2317) - → D s - 0 (D s → ,K*K,K S K) 0.2 0.3 0.4 0.5 0.6 (GeV) 152M BB,hep-ex/0409026 -0.10 0 0.10 (GeV) EE 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 -5 @90% 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?
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B. Golob, Belle Cracow Epiphany Conference, 2005 X(3872) Observed by Belle with 152M BB B ± → K ± + - J/ l+l-l+l- 152M BB, PRL91,262001 (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=3872.4 ±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/ )
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5.20 5.25 5.30 M bc B. Golob, Belle Cracow Epiphany Conference, 2005 X(3872) B ± → K ± + - 0 J/ -0.1 0.1 EE M bc and E in 25 MeV bins of M( + - 0 ) consistent with 0 13.1±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( + - )
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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?
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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)x10 -5 275M BB, hep-ex/0408126
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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 cc 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)
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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/0411005 Searches in decays,“high energy” (charm baryon,B) Searches in secondary interactions,“low energy” (KN + (1540)X) (KN (1520)X) < 2%(90%CL)
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B. Golob, Belle Cracow Epiphany Conference, 2005 Pentaquark searches B decays B 0 p pK S B + p pK + (1540) + * (1600) ++ c0c0 c *+ B 0 p + D ( * )- p M( c 0 )=3099 MeV(H1) =3.5 MeV (det. resol.) B 0 p D 0 p @90% CL 155M BB,hep-ex/0411005 B 0 p + D - p 303 ±21 evts.
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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/0409026 X(3872) → J/ S.Olsen,GHP’04 Y(3940) hep-ex/0408126 resonance in cc recoil T.Ziegler,GHP’04 c (2s) PRL89,102001 PRD70,071102 c (2800) hep-ex/0412069 D ** broad states PRD69,112002 c + p structure hep-ex/0409005 PQ searches hep-ex/0411005
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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/0409026 X(3872)B → KX + - J/ + - 0 ( ) J/ quantum num., decay modes hep-ex/0408116 S.Olsen,GHP’04 Y(3940)B → KY J/ M, hep-ex/0408126 X(3940)continuum, cc recoil M recoil,DD * M, T.Ziegler,GHP’04 c (2s) continuum, cc recoil M recoil PRD(R)70,071102 c (2800) continuum c+c+ , (mixing) hep-ex/0412069 broad D ** B + → D ** + D (*) Br’sPRD69,112002 c + pB - → c + p - M( c + p )M, hep-ex/0409005 + (1540) sec. int. pKpK S existence?hep-ex/0411005 +, *++, c 0, c *+ B decayspK S,pK +, D ( * )- p,D 0 p existence?hep-ex/0411005 +, *++, 3/2 --, 3/2 + charm baryon decays pK S,pK +, - -, - + + existence?
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PQ backup
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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) + 131 fb -1
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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
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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) < 2% @90% CL assuming Br( + → pK S )=25% m 155M BB,hep-ex/0411005
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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
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D sJ backup
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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))=2317.2 ± 0.5 ± 0.9 MeV M(D sJ (2460))=2456.5 ± 1.3 ± 1.3 MeV (D sJ (2317))<4.6 MeV @90% CL (D sJ (2460))<5.5 MeV @90% CL Br(D sJ (2460) → D s + )/Br(D sJ (2460) → D s *+ 0 )=0.55±0.13±0.08
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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: 2320.0±1.1±2.0 and 2459.5±0.9±2.0 MeV;
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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 +
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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 3.0 9.5 B D D sJ (2317) [D s * ] 4.0 -1.4 +1.5 (<8.4) 3.5 B D D sJ (2460) [D s * 0 ] 14.8 -2.5 +2.8 4.4 8.6 B D D sJ (2460) [D s ] 6.4 0.8 1.9 11 B D D sJ (2460) [D s * ] 2.6 -1.0 +1.1 (<5.7) 3.0 B D D sJ (2460) [D s + -] 1.0 -0.4 +0.5 (<2.3) 2.6 B D D sJ (2460) [D s 0 ] 0.2 -0.5 +0.7 (<1.7) -- B D* D sJ (2317) [D s 0 ] 3.1 -1.7 +2.1 (<8.5) 2.0 B D* D sJ (2460) [D s * 0 ] 28.7 -6.4 +7.4 8.6 6.9 B D* D sJ (2460) [D s ] 12.7 -2.0 +2.2 3.8 10 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
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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) + 16.6±4.4 evts.
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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
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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 )= (5.3+1.4 ± 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 -5 @90% 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
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D** backup
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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
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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
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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.:
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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 * )= 2461.6±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/0011044 errors: stat. syst. model varying selection; track, PID eff.; fits with D v *,B v *,constant = 0 for default fit = 240-360 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
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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.:
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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 )= 2421.4±1.5±0.4±0.8 MeV; (D 1 )=23.7±2.7±0.2±0.4 MeV; = 0 for default fit = 100-170 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.
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X(3872) backup
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B. Golob, Belle Cracow Epiphany Conference, 2005 X(3872) backup slide c’c’ J/ cc c0 c1 c2 ’’ ”” hchc c”c” hc’hc’ c1 ’ c2 22 33 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
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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/
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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.
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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
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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>)
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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
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B. Golob, Belle Cracow Epiphany Conference, 2005 X(3872) B ± → K ± + - 0 J/ region I region III 4.3±6.2 6.4±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.)
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Y(3940) backup
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B. Golob, Belle Cracow Epiphany Conference, 2005 Y(3940) B → K J/ | E| < 0.03 GeV, 5.2725< M bc < 5.2875 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
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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)
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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
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cc recoil backup
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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 0.009 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
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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
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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 cc c (2s) direct reconstr. recoil M = 3.630 0.008 GeV N = 164 30
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Isotriplet of charmed baryons backup
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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 )= 515.4 ± 3.2 +2.1 -6.0 MeV c (2800) + M-M( c )= 505.4 +5.8 –4.6 +12.4 -2.0 MeV c (2800) ++ M-M( c )= 514.5 ± 3.3 +2.8 -4.9 MeV ~61-75 MeV 275M BB,hep-ex/0412069 xpxp 0.2 0.4 0.6 0.8 1.0 Peterson fragm. function (e + e - → c (2800)X)Br( c (2800) → c = 2-2.6 pb (± 1-2 pb) M( c )-M( c ) 2.2x10 3 evts. 1.5x10 3 evts. 2.8x10 3 evts. c-c- c0c0 c+c+ States tentatively identified as c2 (J P =3/2 -, M~500 MeV); ~15 MeV, mixing with c1 ?
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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- c0c0 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 2.24x10 3 1.54x10 3 2.81x10 3 x p >0.7
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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:
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c p structure backup
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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/0409005
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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)=(3.67 +0.74 -0.66 ± 0.36 ± 0.95)∙10 -5 Br(B - → ( c + p) - )=(3.87 +0.77 -0.72 ± 0.43 ± 1.01)∙10 -5 due to Br( c + → pK - + ) M=3.35 +0.01 -0.02 ± 0.02 GeV =0.07 +0.04 -0.03 ± 0.04 GeV from different bkgd. param.
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