Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 Das BELLE Experiment Das Experiment B-Physik Überblick über neueste Resultate Gerhard.

Präsentation zum Thema: "Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 Das BELLE Experiment Das Experiment B-Physik Überblick über neueste Resultate Gerhard."—  Präsentation transkript:

1 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 Das BELLE Experiment Das Experiment B-Physik Überblick über neueste Resultate Gerhard LEDER Hephy ÖAW-Wien ~1 km in diameter Mt. Tsukuba KEKB Belle KEK Tokyo

2 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 L peak = 1.4 x10 34 cm -2 sec -1 design = 10 34 cm -2 sec KEKB Collider e-e- 8GeV e+e+ 3.5GeV = 0.425 B-Factory (on the 4s resonance) B-Factory (on the 4s resonance) BB threshold BB threshold

3 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 Kontinuierliche Injection [CERN courier Jan/Feb 2004] Kein Grund, Run zu unterbrechen Immer bei ~max. Strömen, Luminosität ~30% more L dt both KEKB & PEP-II HER current LER current continuous injection (new) normal injection (old) Luminosity 01224 Time ~1 fb -1 /day ! (~1x10 6 BB) -

4 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 SVD Der BELLE Detektor

5 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 Unterschied SVD1.6 und SVD2.0 R beampipe 15 mm R layer 1 20 mm R outside 88 mm 6+12+18+18=54 Ladders SVD2 R beampipe 20 mm R layer 1 30 mm R outside 60 mm 8+10+14=32 Ladders SVD1

6 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 Wiener R/O & Trigger Elektronik R-PHI Trigger R-Z Trigger 24 input OR and analog signal input from VATA 2 x 18 FADCTF

7 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 B Zerfälle und das Standard Modell Electro-weak Hadrons Quark level Final state QCD/Lattice New Resonances QCD/Lattice New Resonances b-quark: Heavy variety of decay modes Reiches Feld für fundamentale SM Parameter 1 2 3 V td V tb V cd V cb V ud V ub * * *

8 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 B Zerfälle und Neue Physik Experimental measurements SM predictions agree? Deeper understanding New Physics ? Yes No Key point: A NP ~ A SM (small/forbidden) b ts,d g,,Z W Penguin b xs,d + New particle, Phase

9 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 Methods to extract B signal yield: 1) Cut on M B and fit to E Cut on E and fit to M B 3) Double dimensional fit to M B and E distribution 4) If B->P 1 P 2 P 3 : cut E and M B box and look at resonant structures in M(P 1 P 2 ) mass distribution. Prozedur, um B Signal zu extrahieren Two almost independent variables M B and E can be used to select B meson signal: M B = (E beam ) 2 – ( P i ) 2 E = E i - E beam * * Verwende spezielle Kinematik des Y(4S)

10 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 Continuums Unterdrückung e+e+ e-e- e+e+ e-e- qq Signal B Other B Dominanter Untergrund für seltene Zerfälle: Continuum Jet-like BB sphärisch e + e qq continuum (~3x BB) To suppress: use event shape variables continuum Y (4S)

11 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 Continuums Unterdrückung To separate spherical BB events from jet-like continuum events, topological variables are used: 1)Second Fox-Wolfram moment 2)Super Fox-Wolfram (six modified Fox-Wolfram moments, Fisher discriminant) 3) Angle between B meson and beam axis direction 4) Angle between thrusts of selected B meson particles and all other particles in event Likelihood ratio includes all info.

12 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 Die Standard Modell Physik bei BELLE selbstkonsistent falls SM korrekt V tb *V td V cb *V cd Unitaritäts Dreieck V ub *V ud V cb *V cd V tb *V td V cb *V cd + 1 += 0 ii {i=1,k=3}: V ub *V ud +V cb *V cd +V tb *V td = 0 d s b u V ud V us V ub c V cd V cs V cb t V td V ts V tb CKM-Matrix 1 i 0 B 0 ->ππ B 0 -> π B 0 ->J/ K s B 0 -> K s B 0 ->D ( * ) D ( * ) B 0 -> D*π B 0 ->D* B 0 ->D* B->D CP K V ub *V ud V cb *V cd 1 2 3

13 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 Penguin d b d _ s/d u u W B 0d0d - + V us/d V ub Tree Simplest charmless rare decay modes Tree - Penguin interference Direct CP Violation Key prediction of Kobayashi-Maskawa model Key prediction of Kobayashi-Maskawa model Understanding of Penguin _ _ (B f ) (B f ) _ _ (B f ) (B f ) A CP = Anomaly (New Physics) B 0d0d d b d u u W g + - V ts/d V tb t s/d Direkte CP-Verletzung:B K /

14 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 A CP (B 0 K ) Evidenz für DCPV bei Belle auch bei [ A ( ) 3.2 ] A CP = -0.101 0.025 0.005 [PID efficiency bias correction: A = -0.01 0.004] 275M BB Neu 3.9 significance [submitted to PRL] B 0 K _ B 0 K Signal: 2139 53

15 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 Time-Dependent CP Asymmetry The CP violation manifests itself in proper-time difference distributions of two B meson decays. The time-dependent CP asymmetry ACP is: Standard Model prediction:Sccs = sin2 1, Accs = 0 Ssss = sin2 1, Asss = small

16 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 Rekonstruiere B J/ K 0 Zerfälle Messe Eigenzeit Differenz: t Bestimme flavor von B tag Berechne CP Asymmetry aus beiden t Verteilungen Prinzip der Messung e e e :8.0 GeV e :3.5 GeV B CP DzDz B tag (4S) ~ 0.425 f CP (J/ K 0 ) z c B ~ 200 m Flavor tag

17 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 Prinzip der 1 -Messung mit B J/ K s t z/(cβγ) Flavor-tag decay (B 0 or B 0 ?) J/ KSKS B - B B + B e e more Bs z t=0 f CP

18 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 sin2 1 mit 152 10 6 BB Paaren 4347 signal events @ 152 10 6 BB consistent with no direct CPV poor flavor tag good flavor tag K. Abe et al. [Belle collaboration], BELLE-CONF-0436. Decay modes used: J/ K S ( ), J/ K S (2 0 ), (2S)K S, c1 K S, c K S J/ K*(K S 0 ) J/ K L

19 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 Voriger Detektor (152 10 6 BB) Neuer Detektor (122 10 6 BB) Lebensdauer und Mixing mit neuem Detektor Parameter fit results (with new detector only) [ps] [ps 1 ] Belle preliminary New detector resolution is well understood. Previous data sets and fitting function for them are unchanged.

20 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 CP violation same as J/ Ks within the Standard Model (SM) Penguin~O ( 2 ), Tree~O( 4 ) deviation = O(1)% Indirect CP Violation : Mixing und/oder Tree - Penguin interference sin2 1 (b sqq) = 0.41 0.07 sin2 1 (b ccs) = 0.726 0.037 B0B0 B0B0 B0B0 VcbVcb V tb V* V tb V* 2 td J/ KSKS KSKS VcbVcb

21 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 B 0 K 0 Similar to J/ K L recon. + sophisticated continuum suppression includes Ks (Nsig=13 5) K S Nsig=139 14 purity 0.63 pB*pB* Nsig= 36 15 K L purity 0.17 275M BB [hep-ex/0409049]

22 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 B K 0 CPV Resultat K S + K L : S ( K 0 ) = +0.06 ±0.33 ±0.09 A ( K 0 ) = +0.08 ±0.22 ±0.09 sin2 1 ~2.2 away from SM K S + K L : S ( K 0 ) = +0.06 ±0.33 ±0.09 A ( K 0 ) = +0.08 ±0.22 ±0.09 sin2 1 ~2.2 away from SM 275M BB Poor tags Good tags S = 0.736 fit [hep-ex/0409049]

23 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 BABAR Resultate für B 0 K 0 227M BB pairs BABAR-CONF 04/033 B A B AR

24 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 K S New modes ! Nsig=31 7 purity 0.56 Nsig=102 18 purity 0.58 f 0 (980)K S S = +0.75 0.64 S = 0.47 0.41 0.08 A = 0.26 0.48 0.15 A = 0.39 0.27 0.08 Raw Asymmetry Good tags S = 0.736 fit 0.13 0.16 Good tags B 0 K S & f 0 (980)K S (~0 @SM) (~2.9 @SM) sin2 1

25 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 sin2 1 from b s penguins at FPCP04 sin2 1 (b sqq) = 0.41 0.07 sin2 1 (b ccs) = 0.726 0.037 CL = 0.00012 (3.8 )

26 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 Neue Physik bei B K 0 ? B K s theoretisch verstanden A = 0.08 ± 0.22 ± 0.09 sin2 1eff = 0.06 ± 0.22 ± 0.09 2,2 Abweichung von SM SM predicts same CPV in b ccs and sqq. SM predicts same CPV in b ccs and sqq. New physics may deviate CPV in b ccs from sqq + SM penguin New process with different CP phase sin2 1 (b sqq) = 0.41 0.07 sin2 1 (b ccs) = 0.726 0.037 CL = 0.00012 (3.8 )

27 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 Radiative and EW Penguins Br(bs ) 3.5 ×10 Br(bsl + l em × Br(bs ) 10 New particle (via loops) may make appreciable contribution to decay rates and/or asymmetries. Good testing ground of SM and beyond SM. bs, sl + l decays proceed via FCNC Box and penguin diagrams bs bsl + l Zukünftige Untersuchungen:

28 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 X(3872) Produktion in B Zerfällen 35±7 events M=3872.0±0.8 MeV <2.3MeV (90%) Recently, Belle observed the X(3872) in B + ->X(3872) K + decay, with X(3872)->J/ + - (confirmed by CDF, D0 and BaBar). M(J/ + -) – M(J/ ) X(3872) M(J/ + -) Br(B - K X 3872 ) Br(X 3872 J/ ) Br(B - K ) Br( J/ ) = 0.063 ± 0.012 ± 0.007

29 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 Charmonium Spektroskopie hchc c c J/ c0 c1 c2 h c c1 c2 Isospin 0++ allowed Isospin 1-- violating Decay to J/ + - < 1 MeV/c 2 X(3872) 2M D M D* +M D

30 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 Studie der X(3872) Produktion in B Zerfällen X c2 (X J/ = 0.42 ± 0.45 ± 0.23 <1.1 (90%CL) Search for B X(3872)K decay, with X(3872) c2 Search for B X(3872)K decay, with X(3872) J X J/ (X J/ = 0.22 ± 0.12 ± 0.06 <0.40 (90%CL) MBMB E MBMB MXMX E X Helicity angle: if J p =1+- (h c ), sin 2 angular distribution is expected. ruled out by data. |cos | 152x10 6 BB pairs

31 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 Studie vom B + X(3872) K + Zerfall, X(3872) J/ + - 0 These events are almost pure signal N evt =10.0 ± 3.6 S/N = 5/1 Signif = 5.8 events with M(3 )>0.75 GeV 274x10 6 BB pairs | M(J/ + - ) – 3872. | < 12 MeV/c 2 Events within B signal region and mass interval: X J/ (X J/ = 0.8 ± 0.3 (stat) ± 0.1(syst) Assuming events with M(3 ) > 0.75 as J/ : It provides support for DD* molecular interpretation of X(3872).

32 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 Welcher Zustand ist X(3872)? Keine guten cc Kandidaten für X(3872): _ c h c c1 2 c2 3 M too low and too small angular distn rules out 1 J/ way too small c too small; (PRL 93, 2003) c should dominate J/ c & DD) too small - Isospin violating decays to J/ + -

33 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 Neue Charmonium Resonanz ? sin2 1 (NEW World Av.) =0.736±0.049 Interpretation: Masse gerade an der D 0 D *0 Schwelle lose gebundenes molecular charmonium, oder ein (1 3 D 2 ) Zustand? Ersteres in der Literatur diskutiert seit 1975: –ausgelöst durch komplizierte Struktur von ( e + e - ->hadrons ) bei SPEAR M. Bander, G.L. Shaw, P. Thomas, PRL 36, 695 (1976) M.B. Voloshin, L.B. Okun JETP Lett. 23, (1976), Pisma Zh.Eksp.Teor.Fiz.23, 369 (1976) A.De Rujula, H.Georgi, S.L.Glashow, PRL 38 (1977) –WW beschrieben durch -Austausch gibt attraktive Kraft für DD*, BB* N.A. Tornqvist, PRL 67, 556 (1991), Z.Phys. C61, 525(1994) A.V. Manohar, M.B. Wise,Nucl.Phys. B339, 17(1993) Q q Q q D 0 D *0 Molekül Diquark Model (Qq) are colored Lose Bindung Ältere Ideen: Decays to (QQ)+(light mesons) via quark rearrangement which suppresses the width. Stärkere Bindung QQ qq

34 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 Zusammenfassung (1) SM bisher überraschend selbst in Details erfüllt! Bestimmung der CKM-Matrix-Elemente im SM Indirekte CP-Verletzung A(t) bestimmt mit hoher Präzision sin2 1 (b ccs) = 0.726 0.037 Grosse Anstrengung auch die beiden anderen Winkel zu messen ( 2 und 3 ) Außerdem Seitenlängen des Dreiecks: m d und m s, sowie V ub /V cb etc. sin2 1 (b sqq) = 0.41 0.07 Bedeutet anderer Wert (3.8 schon neue Physik oder nur Penguin-Beitrag ?

35 Neue Resultate vom BELLE Experiment Mainz G.Leder 17.November 2004 Zusammenfassung (2) Beträchtliche Direkte CP-Verletzung (3.9 ) A CP (B 0 K + - ) = -0.101 0.025 0.005 Asymmetrie Materie-Antimaterie im Universum ? Molekül D* 0 D 0 = 4 Quarkzustand oder konventionelle Erklärung? Neues Gebiet: D s - Spektroskopie etc. BELLE ist bei vielen Gebieten an vorderster Front: SUPERBELLE mit höherer Luminosität