Belle 2008
14th KEKB Accelerator Review Committee, 9–11.Feb.2009/ KEKInt. Lumi. (/fb)

Belle 2008 Run6040❏ Two periods (∼ 8 months.)
Feb.11 – Jun.30, Oct.16 – Dec.22

20Int. Lumi. (/fb)

09.5

1010.511

ECM (GeV)
Y(5S)
Y(4S)
Y(4S) off
Y(2S)
Y(1S)

100

❏ Five Different Energy Points❏ Efficiency ∼ 95 %(Troubles not included)❏ Troubles (∼no effect to analyses)

50• CDC HV (0.5% dead, repaired)0• KLM Readout(2 layers down for 10 days)• ECL Readout (2 ch no signal)

0100

200300Days in Y2008√sLumi. (/fb)

Υ(1S)
9.8

Υ(2S)
10.1

Υ(4S) off.
13.5

Υ(4S)
74.6

Υ(5S)
31.0

Belle 2008 Improvements
LER+HERLERHER

Av. Beam Current (mA)

e63

e65

e67

3000
2000
1000
0250500750
Run No.

0250

500

750

10001250
Run No.

0500

1000
Run No.

0250500750
Run No.

0250500

750

10001250
Run No.

0500

1000
Run No.

0250500750
Run No.

0250

50075010001250
Run No.

05001000
Run No.

Av. Lum (*1032(015010050

Av. Trigger Rate (Hz)08006004002000❏ Trigger Data read out by COPPER❏ New Global Trigger Decisioin Logic• upto 64 trigger input• upto 160 different trigger output• flexible injection veto
• ANN trigger test

• new Bhabha trigger test

Belle Upgrade R&D Highlights

Belle Upgrade Concept❏ More physics events (∝ Lumi ⇒ ×10 trigger Rate O(10) kHz )❏ More background (∝ Beam Current × Vacuum ⇒ ×20)

❏ Faster and Finer• Small-Cell Drift Chamber, Pixel Detector• “Deadtimeless” Pipelined readout• More Timing information❏ Better PID

Baseline Design

Vertex Detector

T.Tsuboyama

DEPFET Pixel Detector

T.Tsuboyama

Silicon Strip Detector

T.Tsuboyama

Barrel PID TOP (Time-Of-Propagation)❏ Complete/realistic prototype• MCP-PMT• Focusing Mirror• Container• Amp+CFD(constant fraction discriminator)❏ Test at KEK Fuji beam line (2 GeV e− )875mm

1655mm❏ Timing Resolution as expectedEndcap PID ARICH (Aerogel Ring Image CHerenkov)❏ Focusing Radiator❏ Six 144ch HAPD(Single Photon Sensitive)❏ dedicated readout ASIC
❏ Test at KEK Fuji beam line (2 GeV e− )• Cherenkov Ring observed• 6 p.e./track• 13.2 mrad Resolution obtainedECLFINESSETKO❏ TKO Waveform Digitizer❏ Waveform Fitting in COPPER❏ Installed in Endcap for Test
• Took Data for 1 week

• Energy Reconstruction confirmed

VMEBhabha❏ VME Version first prototype

Belle Physics Highlightsfrom our52 published Journal papers
and32 conference contribution papers

Pure Leptonic B decay B → τν with semileptonic Tag❏ Confirmation of B → τν search
Hadronic Mode, PRL 97, 251802 (2006)❏ require semileptonic decay in other B• exclusive reconstruction of B → D(∗) ℓν❏ 657 Million BB+0.38+0.35
B(B → τν) = 1.65−0.37(stat.)−0.37(syst.) × 10−4

❏ 3.8 σ excess❏ No additional activity in ECL

400
350
300
250
200
150
10050
00 0.25 0.5 0.75 1
EECL (GeV)

H± Mass (GeV)❏ consistent with hadronic tag result
arXiv:0809.3834

Events / 0.05 GeV+21Nsig = 154+36−35 (stat.)−22 (syst.)

1000

800

icnptole600

iemeSll
Be

400

200
Tevatron Run I0020LEP Excluded
4060❏ constrain in SUSY parameter

80

100tan β“Υ(5S)”→ Υ(nS)π+π−
M(µµ) (GeV/c2)

PRL 100, 112001 (2008)
10.8(a) µµππ candidates

10.6❏ Measurement of Processe+ e− →“Υ(5S)”→ Υ(nS)π+ π−

10.4
10.2

❏ Anomalously large width observed
only in “Υ(5S)”

109.8
9.6
9.4
9.2
90.4

0.6

0.8

11.2

1.4

Υ (nS)ππ cross section (pb)∆M = M(µµππ)-M(µµ) (GeV/c2)

76
54

Υ(2S)
Υ(3S)
Υ(4S)
“Υ(5S)”

Γtotal
0.032 MeV
0.020 MeV
20.5 MeV110 MeV

ΓΥ(nS)π+ π−60 keV9 keV
19 keV590 keV

arXiv:0808.2445 ❏ Dedicated scan performed√(a) Fit with common µ and Γ, χ2/n.d.f. = 39.4/16• 10 s points
Υ (1S)ππΥ (2S)ππ• 7.6 fb−1

Υ (3S)ππ❏ Mass Peak at 10889.6±2.3 MeV

3❏ different from Υ(5S) (10865±8 MeV)

21

❏ Analogous to Y(4260) for charmonium

0
10.75

10.8

10.85

10.9

10.95

1111.05

CM Energy (GeV)❏ Loop process ⇒ sensitive to New Physics❏ Major Topic in Super B Factory❏ Many K, K∗ decay modes
K+ π− , K0S π+ , K+ π0 and K0S❏ + e+ e− or µ+ µ−

AFB

Properties of B → K(∗)ℓ+ℓ− decay
1.4
1.2
10.8
0.6
0.4
0.2
0-0.2-0.4

02420
1000.60.8
1MKπ (GeV)

B → K∗ ℓ+ ℓ−
B → Kℓ+ ℓ−

12214161820

21.2

arXiv:0810.0335v1 ❏ AFB deviates from the SM?
2
1.5
10.5
0-0.5
-1-1.5-2

AI

Events / 2.5MeV/c2

Events / 15MeV

30

10q (GeV /c )100

504082❏ 657 million BB60

68060
40
2005.2 5.225 5.25 5.275 5.3
Mbc (GeV/c2)

Nsig
230+24−23
166+15−16B(×10−7 )+1.1 ± 0.9
10.8−1.0+0.5
4.8−0.4± 0.302.55

7.5 10 12.5 15 17.5 20 22.5 25
q2(GeV2/c2)❏ Isospin symmetry consistent with 0?
❏ Need More LuminosityB → Kπ Puzzle in Nature❏ Paper published in Nature
Nature Vol.452 20 March 2008

0AK± π∓=N(B → K− π+ ) − N(B0 → K+ π− )0N(B → K− π+ ) + N(B0 → K+ π− )= −0.094 ± 0.018 ± 0.008∆A ≡ AK± π0 − AK± π∓ = +0.164 ± 0.037❏ both more than 4 σ significant❏ These significant deviations indicate,• missing knowledge of strong interaction,• Something “unknown” in loop diagram, or• Possible New source of CP violation

Inclusive B → Xsγ❏ moments of Eγ spectrum❏ Full usage of 657 milion BB

arXiv:0804.1580

hEγ i= 2.281 ± 0.032 ± 0.053 ± 0.002 GeV
hE2γ i − hEγ i2 = 0.040 ± 0.016 ± 0.02 GeV26000❏ important input for HQET parameters4000µ2π (GeV 2)

Photons / 50 MeV❏ Eγ Cut lower to 1.7 GeV

2000

ICHEP08

00.45

-2000

0.4

-4000

0.35

1.5

2

2.533.54E γ (GeV)

HFAG

0.54.55

Xc l νXc l ν + Xs γ
4.6

4.65

4.7mb (GeV)

B(B → Xs γ) = (3.31 ± 0.19 ± 0.37 ± 0.01) × 10−4

❏ crucial for determination of Vcb , Vub