collaboration
description
Transcript of collaboration
collaborationLCPAC 2006 Status Report
S.L. Olsen U. of Hawai’i
Publications
• 164 journal papers published or submitted
• ~42 papers submitted since LCPAC-2005
• ~8 currently in “authorship confirmation”
• …
Notable recent results
• Observation of bd• Evidence for BKK• Large direct CPV in B+K+0 decays• Observation of a FB asymm in BK*l+l-
• Observation of a c1’ candidate in DD• A new charmonium-like state, X(3940)• New csu baryons, cx(2980) and cx(3077)• …
Collaboration is stable
•Institutions:•Nat’l Kaohsiung Normal U.•Utkal University•Aomori University•Tsukuba University
•~25 individuals
•Institutions:•Nova Gorica Inst, Slovenia
•~35 individuals
Withdrawals: New members:
Spokesperson changes
Aihara Olsen Yamauchi
Iijima Browder
Yamauchi
ふにきがいれ , ぉにがそと
New spokespersons all ran on platforms promising major
reorganization of Belle
elle continues to perform very well
SVD-2 team continue their heroics
Belle’s long march
SVD2
SVD performance
A.Kibayashi
4 layers + improved coverage better tracking effic
October Meltdown!!
Quick fix
Solder wires directlyto the repeater board
Beam off: 10/20
Resume Data taking 11/4
(connector establishedoutside the detector
during this past month)
more details from Uno-san
Tracking with high backgrounds
0.3%
Pt resolution ( in %)
(B: 21MeV)
New “Global” track finder
Standard track finder
3x Bkg
Tracking effic.improvements:+7% for J/y KS; +60% for D*+D*-
0 detection
M(0) resolution ( in MeV)
4.5MeV
100MeV 1 GeV
(B: 8MeV)
0 line shapeData vs MC
0 detection effic is sensitiveto bkg conditions; ECL reconcode.is being improved
Particle ID
~87%
~8% ACC dead tubes
w/o Event Builder
Upgrade
DAQ and computing are still keeping up
albeit just barely
Present operation
Faster signal processingwith CMS chip in SVD(Silcon vertex det.)
New pipelined dataAcquisition system (COPPER)
1200 new Dell servers
Katayama’s talk this afternoon
The Belle Physics Program
1) Measure of Fundamental SM Params:
CKM elements & phases
2) Search for New Physics:
look for evidence of new particles in loops
3) Unanticipated new phenomena:
large (e+e-cccc), X(3872),X(3940),Y(3940),..
4) + lots of “bread & butter”
c’, c2’, D**,c*, cx,-physics, spin frag-fcn,…
I can only give a few small tastes from this rich & flavorful menu
BB00 J/ J/ K K00 sin21= 0.652 ±0.039 (stat) ±0.020 (syst) A = 0.010 ±0.026 (stat) ±0.036 (syst)
B0 tag_
B0 tag
Precis
ion measu
rement
well underst
ood meth
od
CPV in BCPV in B++--
)(08.0)(42.009.0
)()(30.000.0 10.009.0
syststatS
syststatA
Results:
Low quality tag
High quality tag
q=1 q=-1
(274 106 BB pairs)
No CPV φ2 is near 900
Somov, Schwartz et al hep-ex/0601024
Belle Constraints on Belle Constraints on 2 2 ((αα))
B [hep-ex/0502035] & combined
11375
93
2
12112
at 90% CL
Belle method for 3: Dalitz 3) fCOM = D KS
B+:
B-:
m+=m(Ks+), m=m(Ks) CPV: Asymmetry in Dalitz dist.:
r
r |A2|
|A1|r =
2m
2m
0 D 2m
2m
0 D obtainfromtagged D0
(D*+ D0+)sample
Poluektov, Bondar et al hep-ex/0504013
Constraints of the Unitarity Triangle
World average as of summer 2005
from GLW, ADS, Dalitz and sin(2φ1+φ3): γ/φ3=70 -14°+12
Simplistic(?) summation: 1+ 2+ 3 182o ~20o
CP angles only
1~20o
1~70o
sin21
1
?
Disfavored>2
Simplistic(?) summation: 1+ 2+ 3 182o ~20o
2-fold ambiguity21 -21
Ambiguity removed by Dalitz analysis of B0D0(Ks)h
Krokovny etal hep-ex/0507065
How about the CKM triangle’s sides?
1
2
3
Vtd Vtb
Vcd Vcb
Vud Vub*
*
*
md
& b d
b c l
b u ℓ-
ℓ
Belle Inclusive |Vub|Electron energy
at endpoint • Pth = 1.9 GeV/c
• Systematic limited
Hadronic and leptonic
invariant mass (Mx, q2) • Use full recon tag.• P+ also measured.
Non-experimental error dominated by errors of shape function parameters.
0.14 30.15(4.09 0.19 0.20 0.18) 10ubV
PDG 2002:(3.6 0.7) x 10-3
Limosani et al PLB 621, 28
Bizjak et al PRL 95, 141801
Bℓ Decay Search
Upper limits at EPS05
SM prediction
B search close to SM expectation
Measures fB|Vub|2
Ikado et al, hep-ex/0507034
First Observation of bd
Addresses the same physics issue as Bs- Bs mixing (future Tevatron RunII goal).
_
signal
K*other B
Mohapatra. Nakao, Nishida et al hep-ex/0506079
Constraint on |Vtd/ Vts |
Belle combined
0.143 < |Vtd/Vts| < 0.260 (95%CL)
= 0.032 0.008 0.0030.002
Same physics as Bs mixing
Current status
CPV angles only:η=0.321±0.027=0.193±0.57
sides only:η=0.342±0.022 =0.216±0.036
SM with KM ansatz works remarkably well for tree-level
processes
Next step: Look for new physics in penguin loops
Example: bsss
Example: no KM phase
SM: sin21 = sin21 from BJ/ KS (bc c s)
unless there are other, non-SM particles in the loop
eff
Vtd
Vtd
+
1
B B
, (’,
1
or’,
_
*
*
_
00
Significant CP Violation in a bs penguin mode!!
Chen et al PRD 72012
>>all systematically below sin(2)
>>QCD corrections : sin2(penguin)>sin2(tree)
[Beneke, hep-ph/0505075][Cheng,Chua,Soni, hep-ph/0506268]
recent QCD factorization estimates :
sin2φ1(penguin)-sin2φ1(tree)
Many bs modes were studied:
sin21(penguin) = 0.50 0.06
(HFAG’s “naïve average”)
0.4-
AFB for B K*ℓ+ℓ-
(loops with virtual t’s, W’s, & Z’s)
new physics in
EW penguins? Interference btw and Z
AFB (Kℓ+ℓ -) = 0.09 0.14 (stat)AFB(K*ℓ+ℓ - ) = 0.56 0.13 (stat)3.4 from 0
Not just beauty
• Charm physics• Tau physics• Hadron spectroscopy
– Charmed mesons & baryons
– Charmonium states c’ , c1’
– Mystery states X(3872), X(3940), Y(3940)
• Fragmentation functions• Bs• Dark matter search
D0-D0 mixing
Shipsey @ DIF06
Belle 2006
Zhang, Li et al hep-ex/0601029
High precision -Hayashii et al hep-ex/0502171
bonuses: new mesons, many puzzles!
c’X(3872)
Z(3931)c2’?
e+e-cccc Y(3940)J/
M(J/) MeV
??
Choi et al, PRL 89 112001Choi et al , PRL 91 262001
Choi et al , PRL 94 182002
Uehara et al , PRL 96 082003
Pakhlov et al , hep-ex/0507019
more bonuses: charmed baryons
D0’0(2427)
D0*(2308)
c+-
c0(2800
c+0
c+(2800
c++
c(2800
Kuzmin et alPR D69 112002
Mizuk et alPRL 94 122002
& mesons
(5S) “engineering” rundetails from Alan Schwartz this PM
CLEO PRL 54, 381
(5S)
(4S)
Bs(*)Bs(*)Bq(*)Bq(*)BqBq(*)πBqBqππ
100%BqBq
3-day, 1.86 fb-1 test run
Bf(Bs)< 0.56 x 10-4 (90%CL) ~factor 3 improvement on on world best limit
E M
bc Bs*Bs*
BsBs*
BsBs
Dark matter search
DAMA NaI 3Region
CDMS 04
CDMS 05
Direct dark-matter searches cannot see M<10 GeV region
McElrath, PRD 72, 103508:
Br((1S))~0.4% M < 4.7 GeV
Experimental signature:
(3S)s) nothing
Belle (with optimized trigger):
McElrath prediction
3fb-1 engineering run data@ the (3S) under analysis
Summary
CPV in B decays
BK*ℓ+ℓ- EW penguin
Direct CPV in BK
bd penguins(bd BKK)
|Vub| error <10%
B+
2 error~100
c’ & e+e-cccc
D0*0 & D1*0 mesons
X(3872)
c* baryon triplet
DD-mixing(world’s best limit)
X(3940), Y(3940)
c2’
3 error ~100 ??
Conclusion
• The Belle collaboration remains strong– Our publishing is nearing 1 paper/week– We have two new & energetic spokespersons
• Our detector continues to perform well– Continuously improvements to handle increased luminosity (&bkg)
• We have shown that the CKM ansatz works well for tree processes
– Verified with high precision– Provides “anchor point” for new physics searches
• CPV in penguins provide us with sensitive probe for new physics
– Theoretically and experimentally clean– We are measuring Bf~10-6 penguin processes with high precision
• We have made a number of “unexpected discoveries”– And expect many more in the future
Backup Slides
.“Observation” of Direct CP violation in BK- +
One more nail in the Superweak coffin.
Evidence for BK0 K (hadronic bd s s processes)
Belle@250 fb-1
_
Measurements of B K0 K0 CPV at Super B will be possible.