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Baryonic decays of B mesons. H.Kichimi, June28-July3, 2004 1 Baryonic decays of B mesons H. Kichimi Representing the Belle collaboration BEACH June28-July3, 2004 IIT, Chicago
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Baryonic decays of B mesons. H.Kichimi, June28-July3, 2004 2 Large b-quark mass & CKM matrix elements Large variety in B meson decays b c W -, b u W -, b s qq, b d qq b c W -, b u W -, b s qq, b d qq Hadronizations into mesons and baryons CP and CKM studies in mesonic decays CP and CKM studies in mesonic decays New particles X(3872) and D sJ New particles X(3872) and D sJ Baryonic BFs are large, however not well studied yet. BFs of exclusive baryonic decays Structures in di-baryons Structures in di-baryons Exotic quark states ( pentaquark searches) CP, T and CKM studies in baryonic decays B meson decays Recent results from Belle and Babar are presented.
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Baryonic decays of B mesons. H.Kichimi, June28-July3, 2004 3 ~1 km in diameter / K L detection 14/15 lyr. RPC+Fe Central Drift Chamber small cell +He/C 2 H 5 CsI(Tl) 16X 0 Aerogel Cherenkov cnt. n=1.015~1.030 Si vtx. det. 3 lyr. DSSD TOF conter SC solenoid 1.5T 8 GeV e - 3.5 GeV e + Belle detector 8 GeV e - x 3.5 GeV e + @ 1.2A x 1.6A @ 1.2A x 1.6A L peak = 1.39 x 10 34 sec -1 cm -2 ( June 3 ) Mt. Tsukuba KEKB Belle KEKB and the Belle detector 400 members 59 institutes 13 countries Belle collaboration
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Baryonic decays of B mesons. H.Kichimi, June28-July3, 2004 4 PEP-II and the BaBar detector 9 GeV e - x 3 GeV e + @ 1.5A x 2.3A L peak = 0.92 x 10 34 sec -1 cm -2 PEP-II BaBar
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Baryonic decays of B mesons. H.Kichimi, June28-July3, 2004 5 Luminosity competition KEKB 280 fb -1 PEPII 220 as of June 22 KEKB monthly luminosity 0.94fb -1 /day 22 fb -1 /month 123 fb -1 /year This report is based on the data taken by July 2003 BaBar 124 fb -1 Belle 150 fb -1 July2003 Integrated luminosity (logged) KEKB : 1.392 x 10 34 ( June3) PEP-II: 0.9213x 10 34 (May21) Peak luminosity history
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Baryonic decays of B mesons. H.Kichimi, June28-July3, 2004 6 Contents of this talk 1.Charmfull baryonic B decays b c (W - ) Tree b c (W - ) Tree B 0 c + p B 0 c + p B - c + p B - c + p B 0 c + p B 0 c + p B 0 D 0(*) p p B 0 D 0(*) p p BF and di-baryon mass BF and di-baryon mass 2. Charmless baryonic B decays b s (qq) Penguin b s (qq) Penguin b u (W - ) Tree b u (W - ) Tree BF and di-baryon mass BF and di-baryon mass 3. Searches for pentaquarks W b u u c d s g b s (d) u d s c b c u c d s W
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Baryonic decays of B mesons. H.Kichimi, June28-July3, 2004 7 Charged track momentum & IP, Vee-vertex and B-vertex Si-VTX & CDC Particle ID /K/proton CDC/ACC/TOF (Belle) DIRC (BaBar) and K L 0 multi-layers of RPC + Fe e and CsI(Tl) calorimeters B-signal selection 1 B-event-shape parameter to suppress continuum background Fox-Wolfram moments, cos thrust or Fisher discriminant of those prms Energy difference : E = E B – E beam ~ 10 MeV Beam constrained B mass : M bc = E beam 2 – p B 2 B-B from (4S) at 10.580 GeV/c 2 in the CMS ~ 3 MeV/c 2 4-vector measurement B-signal selection
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Baryonic decays of B mesons. H.Kichimi, June28-July3, 2004 8 E = E B - E beam M bc = E beam 2 – p B 2 140 fb -1 B 0 c + p + - Single Gaussian plus ARGUS function Double Gaussian plus Linear bkgnd M( c + p ) mass B-signal box | E|<30 MeV M bc >5.27GeV/c 2 Data ~ 3 MeV/c 2 B-signal selection 2 Mass window ±14MeV/c 2 569±39
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Baryonic decays of B mesons. H.Kichimi, June28-July3, 2004 9 B0c+pB0c+p Br = ( 2.19 ±0.32±0.57 ) x 10 - 5 +0.56 - 0.49 Stat. Sys. Error of Br ( c + ) First observation of baryonic 2-body decay 19.6 +5.0 - 4.4 Belle : PRL 90, 121802 (2003) 78 fb -1 b c duuu d d B0B0B0B0 cccc p 1. Charmfull decays b c ud W
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Baryonic decays of B mesons. H.Kichimi, June28-July3, 2004 10 B 0 D (*)0 p p D 0 K - + D 0 K - + - + D 0 K - + B 0 D 0 pp B 0 D 0* pp 89 Belle: PRL 89, 151802 (2002) 29.4 fb -1 33.6evnts 24.2evnts 34.2evnts 8.9 5.6 5.1 total 19.3 evnts 5.6 D *0 D 0 0 b c ud W
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Baryonic decays of B mesons. H.Kichimi, June28-July3, 2004 11 B 0 D (*)0 p p 89 Belle: PRL 89, 151802 (2002) 29.4 fb -1 1.18±0.15±0.16 1.20 ±0.21 B + D + pp B + D + pp < 0.15 x 10 -4 B + D* + pp B + D* + pp < 0.15 x 10 -4 B 0 D 0 pp B 0 D* 0 pp +0.33 - 0.29 x10 - 4 UL@90%CL These decays are not allowed by b c transitions ( B yields by E fit ) b c ud W
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Baryonic decays of B mesons. H.Kichimi, June28-July3, 2004 12 B - c + p - 233±19 signals C (2455) 0 C (2520) 0 sideband 32.8 12.2 + 6.6 - 5.9 - 5.9 + 5.6 - 4.9 - 4.9 Belle: new results 140 fb -1 B - c + p - 19.8±1.9 B - c 0 2455 p 3.64 B - c 0 2520 p 1.19 BF x 10 -5 +0.73 - 0.66 +0.55 - 0.48 ~ 25% of the total ( c + p - ) BF Preliminary Observation of a new 2-body decay ( as of Moriond QCD2004 ) b c ud W
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Baryonic decays of B mesons. H.Kichimi, June28-July3, 2004 13 ( c + p) mass C + p) M( c + -)>2.6 & M(p -) >1.6GeV/c 2 to remove c(2455/2520) & (1232) B signals by E fit for each mass bin B - c + p - M( c + p) structure Br = ( 3.79 ) x 10 - 5 BW = 0.15±0.05 Mass = 3.32±0.02 6.1 significance C 0 C + - ) Preliminary 75±17evnts ( as of Moriond QCD2004 ) Phase space function +0.75 - 0.71
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Baryonic decays of B mesons. H.Kichimi, June28-July3, 2004 14 MC helicity 2 /nd Solid line : 0 0.97 Dashed line : 1 1.58 B - c + p - by E fit for each cos bin by E fit for each cos bin Helicity distribution of the ( c + p) system ( <3.6GeV/c 2 ) data: dots MC : histograms Preliminary c+c+ ( c + p) direc. B - at rest Helicity angle p c + p) at rest
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Baryonic decays of B mesons. H.Kichimi, June28-July3, 2004 15 B 0 c + p - - c ++ (2455) c 0 (2455) c ++ (2520) c 0 (2520) M( c + ) Intermediate 3-body decays Belle 140 fb -1 B 0 c + p 10.44±0.71 ±1.25 ±2.71 (*1) B 0 c (2455) ++ p 1.25±0.21 ±0.15 ±0.33 1.25±0.21 ±0.15 ±0.33 B 0 c (2455) 0 p 1.11±0.20 ±0.13 ±0.29 1.11±0.20 ±0.13 ±0.29 B 0 c (2520) ++ p 1.04±0.23 ±0.13 ±0.27 1.04±0.23 ±0.13 ±0.27 B 0 c (2520) 0 p 0.44±0.16 ±0.05 ±0.11 0.44±0.16 ±0.05 ±0.11 44.7±7.640.4±7.1 58.4±13.025.1±9.0 M( c + )+c.c. M( c + )+c.c. (*1) total BF Preliminary x 10 - 4
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Baryonic decays of B mesons. H.Kichimi, June28-July3, 2004 16 B 0 ( c + p) - C ++/0 (2455/2520) excluded B - ( c + p) - B Signals by E fit consistent with 4-body MC phase space, however fine structures however fine structures ? MC 4-body phase space Preliminary M( c + p) structure in 3, 4 body decays
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Baryonic decays of B mesons. H.Kichimi, June28-July3, 2004 17 BFs for Charmfull decays B 0 c + p 10.44±0.71 ±1.25 ±2.71 (*1) B 0 c (2455) ++ p 1.25±0.21 ±0.15 ±0.33 1.25±0.21 ±0.15 ±0.33 B 0 c (2455) 0 p 1.11±0.20 ±0.13 ±0.29 1.11±0.20 ±0.13 ±0.29 B 0 c (2520) ++ p 1.04±0.23 ±0.13 ±0.27 1.04±0.23 ±0.13 ±0.27 B 0 c (2520) 0 p 0.44±0.16 ±0.05 ±0.11 0.44±0.16 ±0.05 ±0.11 UL UL BF x 10 - 4 B - c + p 1.98 ± 0.19 1.98 ± 0.19 B - c (2455) 0 p 0.36 ± 0.07 0.36 ± 0.07 B - c (2520) 0 p 0.12 ± 0.06 0.12 ± 0.06 B 0 c + p 0.22 ±0.03± 0.06 0.22 ±0.03± 0.06 4-body decay 3-body decays 2-body decays +0.06 - 0.05 (*1) total Br. Preliminary Strong suppression of lower multiplicity decays BF(2-body)<<BF(3-body)<<BF(4-body) ~1/10 : 1 : ~10 Stat, sys and error in BF( c + p K - ) (PRL90) Belle new 140 fb -1
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Baryonic decays of B mesons. H.Kichimi, June28-July3, 2004 18 B 0 p - Peaked at threshold Belle: PRL 90, 201802 (2003) 78 fb -1 5.8 39.2 evnts MC Phase Space B 0 p - ( 3.97 ±0.56 ) x10 -6 B 0 p K - < 8.2 x 10 -7 @90%CL B 0 p 0 - < 3.8 x 10 -6 @90%CL +1.00 - 0.80 g b s u d 2. Charmless decays
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Baryonic decays of B mesons. H.Kichimi, June28-July3, 2004 19 B + p p K + B + p p K + 4.89 ±0.54 B + p p + B + p p + 1.76 ±0.21 B 0 p p K 0 B 0 p p K 0 1.56 ±0.19 B + p p K *+ B + p p K *+ 6.7 B + pp + B o ppK s 0 B + ppK *+ B + ppK + B + p p h + MC phase space BF x10 -6 +0.59 - 0.55 +0.42 - 0.37 +0.52 - 0.49 +2.4 - 2.0 +0.9 - 1.1 Belle: PRL 92, 131801 (2004) 78 fb -1 PRL 88, 181803(2002) 29 fb -1 (1)Peaked at threshold (2) BF( pp K ) > BF( pp ) consistent with BF( K) > BF( ) (3) BF( pp K 0 ) < BF( pp K + ) different from mesonic cases (M pp <2.85GeV/c 2 to exclude charm) g b s, d u d W b u ud 95.4 evnts 15.3 37.4 6.7 11.3 5.1 14.5 6.0 First observation in baryonic decay
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Baryonic decays of B mesons. H.Kichimi, June28-July3, 2004 20 B + K + B + 22.9 evnts (M <2.85) threshold peaking Charmonium excluded B + B + + 2.91 ±0.38 B + + < 2.8 @90%CL +0.90 - 0.70 BF x 10 -6 MC phase space Belle New 140fb -1 no signal g b s ss +5.8 - 4.8 7.4 First observation of b s s s decay Hep-ex/0406068 submitted to PRL
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Baryonic decays of B mesons. H.Kichimi, June28-July3, 2004 21 B + p p K + BaBar 80 fb -1 g b s u d Belle: (4.89 ±0.54)x10 -6 (M pp <2.85GeV/c 2 ) +0.59 - 0.55 Preliminary
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Baryonic decays of B mesons. H.Kichimi, June28-July3, 2004 22 B 0 p p BaBar : PRD69, 091503(R) (2004) Dotted curves : signals for Br=1x10 -6 < 2.7 x 10 -7 for B 0 p p BaBar UL@ 90% CL 80 fb -1 b u duuu d d B0B0B0B0 p p no evidence yet W b u ud Br = ( 2.19 ±0.32±0.57 ) x 10 - 5 +0.56 - 0.49 2. B 0 c + p (Belle) Belle : PRD65, 091103(R) (2002) 29 fb -1 Belle UL @ 90% CL < 1.2 x 10 -6 for pp < 1.2 x 10 -6 for pp < 1.0 x 10 -6 for < 1.0 x 10 -6 for < 2.2 x 10 -6 for p < 2.2 x 10 -6 for p 1. Strong suppression relative to 3-body decay by ~1/10, as observed in b c. Br = ( ) x 10 - 6 Br = ( 1.76 ±0.21 ) x 10 - 6 1. B + p p + (Belle) +0.42 - 0.37 2. Consistent with the ratio of Vub/Vcb.
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Baryonic decays of B mesons. H.Kichimi, June28-July3, 2004 23 Mode Mode BaBar BaBar Belle Belle type type B 0 p p < 0.27 < 0.27 < 1.2 < 1.2 b u u d b u u d B 0 < 1.0 < 1.0 b d s s b d s s B 0 p < 2.2 < 2.2 b s u u b s u u B 0 p - 3.97 ±0.56 3.97 ±0.56 b s u u b s u u B 0 p - < 3.8 < 3.8 b s u u b s u u B 0 p K - < 8.2 < 8.2 b d s s b d s s B + p p K + 5.7± 0.7±0.4 5.7± 0.7±0.4 4.89 ±0.54 4.89 ±0.54 b s u u, s d d b s u u, s d d B + p p K *+ 6.7 6.7 b s u u, s d d b s u u, s d d B 0 p p K 0 1.56 ±0.19 1.56 ±0.19 b s u u, s d d b s u u, s d d B 0 p p K *0 < 7.6 < 7.6 b s u u, s d d b s u u, s d d B + p p + 1.76 ±0.21 1.76 ±0.21 b u u d b u u d B + K + 2.91 ±0.36 2.91 ±0.36 b s s s b s s s B + + < 2.8 < 2.8 b d s s b d s s B 0 J/ p < 26 < 26 < 41 < 41 b c c s b c c s B 0 J/ p p < 1.9 < 1.9 b c c d b c c d x10 - 6 +1.00 - 0.08 +0.59 - 0.55 +0.9 - 1.1 +2.4 - 2.0 +0.52 - 0.49 +0.42 - 0.37 +0.90 - 0.70 BFs for Charmless Decays M(pp) < 2.85GeV to remove charm UL @ 90% CL 2-bodys 3-bodys New
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Baryonic decays of B mesons. H.Kichimi, June28-July3, 2004 24 Searches for pentaquarks BaBar : Inclusive searches for +, 5 and N 5 Belle searches will be reported in PQ04. + (1540) p Ks p Ks
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Baryonic decays of B mesons. H.Kichimi, June28-July3, 2004 25 BaBar-1 : Inclusive search for + (1540) Ks p 1.6 – 1.8 GeV/c 2 c + (2285) 1.44 – 1.60 GeV/c 2 + (1540) + Ks p 1.8 – 3.0 GeV/c 2 c + signal only Ks p Preliminary (M ) ~ 2MeV/c 2 for all p* with eff. ~16% Ks from I.P. M Ks ±10MeV/c 2 eff. ~26% M(Ks p) M c+ ) =5~7MeV/c 2 (FWHM) Data-MC in good agreement No evidence All mass region : 1.4 - 5.4 GeV/c 2 98K evnts in c + region 123 fb -1
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Baryonic decays of B mesons. H.Kichimi, June28-July3, 2004 26 m m No signals observed Preliminary c 0 (2470) 0 (1532) 124 fb -1 , p : 258K , p : 8.7K : 16.9K c : 4.2K BaBar-2 Inclusive searches for 5 and N 5 Hadrons 556M evnts
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Baryonic decays of B mesons. H.Kichimi, June28-July3, 2004 27 m K+ m Ks m K- 5 Ks 5 Ks No signals observed 124 fb -1 Preliminary - (1672) C 0 (2470) 5 K + C + (2285) N50N50 N50N50 c : 615.7 K : 6357.7 (evnts) Inclusive searches for 5 and N 5 continued p : 10 x 10 +6 Ks : 2 x 10 +6
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Baryonic decays of B mesons. H.Kichimi, June28-July3, 2004 28 Summary 1. A low mass ( c + p) structure in B - c + p - mass = 3.32±0.02 GeV/c 2 BW = 0.15 ± 0.05 GeV/c 2 mass = 3.32±0.02 GeV/c 2 BW = 0.15 ± 0.05 GeV/c 2 BF ( c + p structure) ~ 20% of the 3-body decay BF ( c + p structure) ~ 20% of the 3-body decay 2. BFs for 2, 3 and 4-body decays are measured precisely. Strong suppression of lower multiplicity decays. Strong suppression of lower multiplicity decays. BF(2-body) << BF(3-body) << BF(4-body) BF(2-body) << BF(3-body) << BF(4-body) 3. b s s s : B + K + is observed. b u u d : B + p p + b u u d : B + p p + 4. Threshold peaking behavior of (pp) (p and ( masses in charmless 3-body decays. 5. Searches for pentaquarks at Belle and BaBar. No positive evidence. ULs will be reported at PQ04. No positive evidence. ULs will be reported at PQ04.
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