rare b decays at belle hsuan-cheng huang ( 黃宣誠 ) national taiwan university 2 nd bcp workshop...
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Rare B Decays at Belle
Hsuan-Cheng Huang (黃宣誠 )National Taiwan University
2nd BCP Workshop @ NTU, TaipeiJune 7 - 9, 2002
7-J un-2002 BCP2 Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.2)
Outline Introduction Charmless Hadronic B Decays Charmless Baryonic B Decays Radiative / EW Penguin B
Decays Suppressed b -> c Decays Summary
7-J un-2002 BCP2 Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.3)
Introduction Rare B decays can be described by various
tree and penguin diagrams They are useful to determine the CKM
unitarity triangle Search for CP violation and probe new physics
7-J un-2002 BCP2 Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.4)
Belle Collaboration
A World-Wide Activity Involving 50 Institutions
14 Nations
7-J un-2002 BCP2 Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.5)
Belle Collaboration ~ 300 authors
7-J un-2002 BCP2 Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.6)
KEK View 日本 茨城県 つくば市
7-J un-2002 BCP2 Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.7)
8GeV electron 3.5GeV positron
(4s) (10.58GeV/c2) = 0.425(4s) B B
KEKB Collider
KEKB Asymmetric e+e- Collider
7-J un-2002 BCP2 Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.8)
KEKB Luminosity: the world’s best !
Peak L 7.251033 cm-2s-1 (Mar. 28, ’02)Daily Integrated L 387 pb-1/day (May 11, ’02)Weekly Integrated L 2.52 fb-1/week (May 9, ’02)
Peak L 7.251033 cm-2s-1 (Mar. 28, ’02)Daily Integrated L 387 pb-1/day (May 11, ’02)Weekly Integrated L 2.52 fb-1/week (May 9, ’02)
82 fb-1
recorded(Jun. 6, ’02)
82 fb-1
recorded(Jun. 6, ’02)
Daily Integrated luminosity history
Integrated luminosity history
43 fb-129 fb-1
7-J un-2002 BCP2 Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.9)
Silicon Vertex Detector (SVD) Impact parameter resolution 55m for p=1GeV/c at normal
incidenceCentral Drift Chamber (CDC) (Pt/Pt)2 = (0.0019Pt)2 + (0.0034)2
Pt in GeV/c2K/ separation with dE/dx in CDC (dE/dx =6.9%) TOF (TOF = 95ps) Aerogel Cerenkov (ACC) Efficiency = ~87%, Fake rate = ~8% up to 3.5GeV/c, e with CsI crystals (ECL) E/E ~ 1.8% @ E=1GeV e : efficiency > 90% (~0.3% fake for p > 1GeV/c)KL and with KLM (RPC chambers) : efficiency > 90% (~2% fake at p > 1GeV/c)
Quite stable performance up to now
ACC
Kaon efficiency contamination
87%
8%
PID(K)>0.6
Belle Detector
7-J un-2002 BCP2 Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.10)
Signals
Analysis Method Identify Signals: beam-constrained mass Mbc and energy difference E
7-J un-2002 NTHU Seminar Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.11)
B hh: Introduction
7-J un-2002 NTHU Seminar Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.12)
K+- K+0 K0+ K00
+- +0 00
B hh: Results Updated measurements with 31.7M BB
mass is assigned to charged tracks Likelihood ratio cut optimized for each mode Shaded area corresponds to background from other rare B
decays ⇒ Better fitting systematics 00 Hint ⇒ Feedback to 2 measurement
Prelim
inary
29 fb-1
7-J un-2002 NTHU Seminar Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.13)
B hh: Branching Fractions
00 Hint No KK yet! Pre
liminary
BaBar 55.6 fb-
1
*
*
* 20.6 fb-1
Bartoldus @ FPCP
7-J un-2002 NTHU Seminar Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.14)
B hh: Direct CP Search
Prelim
inary
K+-
K-+
K+0
K-0
+0
-0
K0-
K0+
bb quark
Fluctuation?
BaBar 55.6 fb-1
7-J un-2002 BCP2 Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.15)
B (‘)h: Introduction
7-J un-2002 BCP2 Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.16)
Results of B K* / ’K
98
29 fb-1
7-J un-2002 BCP2 Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.17)
B K Results
Prelim
inary
7-J un-2002 BCP2 Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.18)
B Results
Prelim
inary
7-J un-2002 BCP2 Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.19)
B (‘) h: Summary
Prelim
inary
7-J un-2002 BCP2 Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.20)
B h: Introduction
7-J un-2002 BCP2 Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.21)
B h: Results
Prelim
inary
0
0 M
7-J un-2002 BCP2 Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.22)
B h: Consistency Check
7-J un-2002 BCP2 Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.23)
B h: Summary
Prelim
inary
7-J un-2002 BCP2 Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.24)
B Khh Dalitz
Sizable
PRD 65 092005 (2002)
Three-Body Charmless B Decays
First Observations of
7-J un-2002 BCP2 Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.25)
B -> K h h’
A. Garmash @ FPCP* PRD 65 092005 (2002)** H.C.Huang@Moriond 02 EW
Prelim
inary
7-J un-2002 BCP2 Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.26)
Pseudo-Two-Body Decay BFsB+ K+ + -
B+ K+ K+ K-
B+ KS K+ K-
B+ KS + -
PRD 65 092005 (2002)
Prelim
inary
29 fb-1
43 fb-1
Gabyshev @ DPF2002
7-J un-2002 BCP2 Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.27)
Charmless B Decays to Baryons
PRD 65, 091103 R (2002)
7-J un-2002 BCP2 Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.28)
First Observation of Charmless Baryonic B Decays
7-J un-2002 BCP2 Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.29)
3-body Baryonic B Decays, cont.
Chua, Hou, Tsaihep-ph/0204186
fJ(2220)?
Chua,
Hou & Soni, PRL 86, 4247 (2001)
J/
7-J un-2002 BCP Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.30)
EM
Starting to Constrain NP
Radiative B Decays
Prelim
inary
)892(*KB
PRL 88, 101805 (2002)
BaBar(20.6 fb-1)
7-J un-2002 BCP Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.31)
UL
PLB’01
More Radiative Penguins
45M
BB
B
Exclusive (K, K) / Inclusive = (35 ± 8) %
hep-ex/0205025, submitted to PRL
7-J un-2002 BCP Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.32)
Signa
l !
First Obseervation of ElectroWeak Penguin !?
.B K Observation
PRL 88 021801 (2002)
But, BaBar 20.7 fb-1
6* 105.3)( KBB
610.030.018.024.0 10)84.0()(
KBB
FPCP 56.4 fb-1
7-J un-2002 BCP Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.33)
Inclusive B -> Xsl+l-
Xs = (K+ or KS) + (0 ~ 4) + (upto 1 0)
6 6
8.0 3.97.3 3.8
7.9 5.4 2.3 1.67.4 3.8 2.1 1.7
11.0 9.6 1.6
2.6
1.410.4 8.0 1
1.32.4
1.2
1.2
.6
(5.1
( 10 ) ( 10 ) .
16.6 11.0 2.1
30.7 8.9 4.4
47.6 7.1 4
)
.8
s
s
s
X e e
X
X
Mode #Signal BF UL Signif
First Evidence!
First Evidence!
Senyo@FPCP43 fb-1
Prelim
inary
7-J un-2002 BCP Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.34)
Inclusive B -> Xsl+l-
With higher statistics, more information will be obtained from M(Xs) and M(ll) distributions
J/psi and psi’ vetoes
KK*
MXs Distribution Mll Distribution
MC based on the NNLO calculationAli-Lunghi-Greub-Hiller, hep-ph/0112300
7-J un-2002 BCP2 Workshop Hsuan-Cheng Huang
Rare B Meson Decays at Belle (p.35)
Summary Recent Rare B Results from Belle
have been presented First Observations:
B ppK±, Khh, Kll, K First Evidence: B ± , K± , Xsll “Re”-Observation: B± K±
Improved Measurement: B K, , K*
More and more interesting results are coming 80fb-1 @ ICHEP2002