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Stato di CDF
22 Settembre 2005
Giovanni Punzi
(Pisa)
Highlights
• Run IIb upgrades completi all’85%– Completamento previsto nella prima parte del 2006– SVT Upgrade 2/3 completo e operativo
• Nuovo record di luminosita’: 1.4 E32 (4 Agosto)• 1 fb-1 su nastro (10 Settembre)• Il rivelatore e’ stabile e funziona bene• Software di ricostruzione e’ stabile• La latenza tra la presa dati e la disponibilita’ dei dati
processati per l’analisi e’ stata ridotta a ~ 6 settimane• Shutdown rimandato al 2006 (date ancora incerte)• Gli istogrammi accumulano statistica…
Data Taking Efficiencies
Initial Luminosity (1030 cm-1s-1) Data Taking Efficiency
~85% of Run IIb Upgrade Projects were commissioned with beam during this period.
Record 1.4 x 1032
2002 2003 2004 2005 2002 2003 2004 2005
83%
Data for Physics
COT Compromised Period
QCDElectroweak, Beyond SMBTop
Sep-Dec ‘04 Shutdown
Recorded
SM Higgs
Data up to Aug. 2004 Recorded: 530 pb-1
Physics: 320 - 470 pb-1
Data up to Aug. 2005 Recorded: 950 pb-1
Physics: 620 ~ 880 pb-1
Store Number (Aug.23,2005)
Achieved vs Projected Integrated Luminosity
On the path to 8 fb-1 integrated luminosity in 2009
Projected Peak Luminosity
Top Line: all run II upgrades workBottom line: none work
First e-cooling demonstration – 07/15/05
-0.002 -0.001 0 0.001 0.002
Fract. momentum spread
Dist. function (arb. units)
Pbar beam: 63.5e10Barrier-bucket bunched.Bunch length 1.7-usTr. emittance (95%,n) kept at 4-pi mm-mradElectron beam current: 200 mATraces are 15 min apart
CDFII Challenge
Continuare a raccogliere dati efficientemente a luminosita’ crescenti fino al 2009
DAQ / Trigger Specifications
Run IIa Specification
Run IIa Achieved (typical)
Run IIb Specification
Peak Luminosity 0.9 x 1032 0.9 x 1032 3.0 x 1032
L1 Accept 45 kHz 25 kHz 30 kHz
L2 Accept 300 Hz 350 Hz 1000 Hz
L3 Accept 75 Hz 80 Hz 100 Hz
Data Logging 20 MB/s 20 MB/s 60 MB/s
Deadtime Trigger 5% 5% 10%
Physics Triggers a 3 x 1032 cm-2 s-1
• La Trigger Table attuale funziona bene fino a ~1.5 x 1032 cm-2s-1
– Significativo e continuo sforzo di miglioramento su molti fronti• Trigger upgrades: migliore purezza con meno processing time.
– Alcuni prescale sono stati addirittura rimossi (multibody B trigger !)• Veto high multiplicity events
• Trigger Table in sviluppo per ~3 x 1032 cm-2s-1
– 2/3 della statistica comunque raccolti a L<1.5 x 1032
– Strategy: high purity triggers for high luminosity, inclusive heavy flavor triggers at low luminosity (allow larger deadtime)
– Straw Trigger Table in Ottobre 2005.• Scelta finale dei triggers basata su priorita’
di fisica e purezza• Importante contributo italiano anche qui.
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
0 2 4 6 8 10 12 14 16 18 20 22 24
66%34%
Lpeak = 3 x 1032
In 3.5 hours,L < 1.5 x 1032
hours
L(1032)
Run II Publication Status
• 2005 Goal:– 40 submitted papers
• 2005 Status:– 20 submitted papers (9 published, 2 accepted)– 10 papers - drafts under collaboration’s review
• Results approved by CDF physics groups• Drafts approved by internal reviewers
– “Godparents committee” assigned for each paper.
– 27 papers - under godparents committee’s review• Results approved by CDF physics groups
year 2003 2004 2005 (until september)
# submitted 4 1720
(erano 8 a Maggio)
http://www-cdf.fnal.gov/physics/pub_run2/
Italian group contributions to analysis
• B/charm physics– Topics: Bhh (ACP, BR), bp, BsDs & lDs (for Bs mixing), B lifetimes, Bs
BdK*, BK (ACP, BR), D0hh (BR, ACP), D+πππ, pentaquarks, – Groups involved: Padova, Pisa, Roma, Trieste
• High-pt physics– Topics: Zbb, Higgs searches, top physics, hadronic top, top backgrounds, b-tagging,
W+jets, forward W’s– Groups involved: Bologna, Padova (Trento), Pisa, Roma
• Contributions to crucial analysis tools– Computing, sample skimming– Particle Identification with TOF and COT dE/dx– High-Pt b-tagging development– Jet Energy resolution and scale
• Most work in close cooperation amongst Italian groups• A lot of work in close cooperation with non-Italian groups
Wide range of activities: today only a few highlights
l
n
W+
W-
t
t
b-jet
b-jet
jet
jet
Mjj(W)
W ->2 jets calibrano la scala dei jet negli eventi top stessi
Stessa scala per b-jet e light quark (per ora)
Current Best: Fit contemporaneo 2-D alla massa del top e alla scala dei jet (JES) da Mjj(W) nel campione lepton+jets
Mtop
M top =173.5−3.6+3.7 (stat+ JES) GeV/c2 JES =−0.10−0.80
+0.78 (stat) σ
Prospects
Bs
Charmless BVV
BdK*
estimated yield:
123 events
estimated yield:
44 events
•BdK*: yields 123 (CDF 360pb-1) (compare to 173 (Belle 250fb-1) [hep ex/050313] Equivalent uncertainty on polarization measurement
Bs First observation with 180 pb-1 [PRL 95,031801 (2005)]. Analysis update
underway: 12 events 44 events (360 pb-1).
Update BR measurement. Measuring polarization: expect 0.10-0.15 resolution on long. polarization (similar to B-factory first PRL)
Verso la misura del Bs mixing
• Le estrapolazioni assumono di integrare la meta’ della luminosita’ dal 2007 in poi (B-physics solo da meta’ store)
• Sensibilita’ al range favorito dal fit di unitarieta’• In case of no signal 95% C.L. up to 30 ps-1 with 4 fb-1
CDF “Bs Mixing Group”
• ~70 physicists ( 22 italians, 9 phd/post-doc) in CDF are actively involved in the Bs mixing project– Improving the trigger strategy– Understanding the detector– B Lifetime Measurements– Flavor Tagging– B0 Mixing– Bs Mixing
• Big collaborative effort:–Analyse 3 different datasets–Reconstruct 0(20) different decay modes–Perform 2 parallel analysis for both hadronic and semileptonic modes–Study 4 different tagging algorithms–TOF and dE/dx calibrations
Here I mention just two examples of italian contribution
Same side Kaon tagging
B0
B-
Bs
K*0
K+
K- K*0
•Exploits the charge correlation between the b quark and the leading product of b hadronization. Based on PID capability.•Big hopes: initial studies indicate D2 ~3% vs current ~1%
1. Measure K distr. in data2. Tune MC D2
Campione addizionale di Bs semileptonici
+
4GeV-lepton + 1 displaced track trigger
2 displaced track trigger
Additional new sample overlap with the one already used ~ 20%
Effective ~ X 3 more semileptonic Bs yield to be used for MIXING
Basic tools: PID
pK
•Moderate separation at CDFaccurate modeling is crucial •Great effort devoted both to TOF calibration (better resolution) + t0 (reduced tails) and COT dE/dx calibration over wide range
•J/ee, ee•J/mm•D*±D0 s(k) s
• p
Parameterize and combine TOF+dE/dx in a single likelihood
Maximal performance from a unified tool
•Central to many analyses: B reco, Flavor tagging
TOF
dE/dx
• Update analisi in corso: 180 pb-1 360 pb-1
Total yield ~2600 ev (was 900)
• Estimated yields:
~1600 BdK+ - ~400 Bd+ -
• ~700 BsK+K- : (first observed w/ 180 pb-1)
– Misura accurata BR (large U-spin breaking?)
– CP state: Misura lifetime: ~light s
• ?? BsK Visibile… o contraddizione con la teoria.– Limite da 180 pb-1 <5.4·10-6 . Expect (6÷10) ·10-6
• ?? Bs , BdKK Constrain/misura contributi di annichilazione (BR(Bs piu’ grande, meno fondo piu’ sensibile. CDF ha gia’ il Best Limit da 180pb-1 )
180 pb-1
360 pb-1
Charmless BPP
250 fb-1 BaBar)
Direct ACP(B0 K)
Babar -0.133 0.030 (stat.) 0.009 (syst.) Belle -0.113 0.022 (stat.) 0.008 (syst.)
HFAG 2005
ACP compatible with B-factories, systematic uncertainty comparable
In progress: 360pb-1 (ACP)= 4% World best: 2.2% (Belle)
Full RunII statistics: (ACP) 1%
•Other large direct ACP around the corner (unobserved modes!):
•BsKπ (sensitive to , similar to Bdππ, but self-tagging)
bpπ
Lint
360 pb-1
~650 pb-1
CDF 180pb-1
Conclusioni
• Il Tevatron sta seguendo le previsioni piu’ ottimistiche
• Gli upgrades di CDF sono quasi completati
• La collaborazione e’ impegnata a fondo nello sfruttare la luminosita’ per un ricco programma di fisica
BACKUP
s s
• BS J/ +- K+K-
• BVV decays: Heavy and Light state decay with distinct angular distributions and different lifetimes.
Back
• Result (260 pb-1)– 1/4 heavy - 3/4 light state– Lifetime - heavy ~ 2 x light
S / S = 0.71 +0.24-0.28 ± 0.01
• Lifetime difference measures“same” CKM element as m (oscillation frequency)
• Exciting!! Need more data– ~ 5 % sensitivity by 2009 ms = 10 ps-1 S / S = 7%
• Test still possible CP violation effect in Bs mixing
• Perfect U-spin simmetry would predict BR(BsKK)/BR(BdKpi) ~1, but some calculations predict 2 [A. Khodjamirian et al.,Phys.Rev. D68 (2003) 114007].
• Current result favors the second case, but resolution is insufficient
• Current resolution BR(BsKK)/BR(BdKpi) 1.70.31(stat.) more accurate measurement very desirable
• Test with 360 pb-1 will be decisive: expect resolution 0.14(stat.) .
Bs KK
Lint
360 pb-1
Silicon Detectors
• Radiation damage– > 90% of total radiation is due to collisions: NIM A514, 188-193 (2003)
– Bias voltage scans as luminosity accumulates• Study collected charge (hits on tracks) and mean noise• Measurements agree with predictions up to 1 fb-1.
• Efforts to increase the Silicon lifetime– Lowered Silicon operating temp. gradually from -6oC to -10oC.– Thermally isolated SVX from COT inert regions such that the silicon can
be kept cold during COT work.
Lifetime 0 10 fb-1 20 fb-1 30 fb-1 40 fb-18 fb-1
Predicted Silicon Lifetime (note the large uncertainties)
Run IIb Project Status
• Trigger and DAQ Upgrades– Level-1 Track Trigger (XFT):
• Add z (stereo) info for 3D tracking - In production– COT TDC modification to achieve L2 rate of 1000 Hz (readout time)
• 12 out of 20 crates are operational.– Level 2 decision system: faster,flexible - operational since April
2005– Level 2 Silicon Vertex Trigger (SVT)
• Faster - 3 step upgrade: the first 2 steps are operational.– Event Builder: operational since August 2005– Level-3 Computer
• 1st procurement placed(64 PCs) - replace current system in Nov’05
• 2nd procurement ready(64 PCs) - complete ~Jan.06– Data Logging (20 MB/s 60 MB/s)
• 1st step operational (~35MB/s), complete by end of 2005
Installation & commissioning parasitically without interrupting operations.
Run IIb Project Status
• Detector (Calorimeter) Upgrades– Central Preshower upgrade
• Replacing with a finer segmentation system for higher lum.
• operational since early 2005
– Electromagnetic Timing
• New system for cosmic ray rejection
• operational since early 2005
• Run IIb Status– The project is ~85% complete and operational.
– 100% by early 2006.
– commissioned without interrupting operations.
Extrapolation of Trigger Rates
a highly non-linear behavior
Level-2 high pT electron Level-2 high pT muon(0.6 < || < 1.1)
~1% bandwidth at 3 x 1032 cm-2s-1 ~50% bandwidth at 3 x 1032 cm-2s-1
Bunch-by-bunch luminosity gives a better lever arm for the extrapolation.
Example of planned improvements: XFT upgrade
Confirmation of XFT tracks by stereo layers is expected to yield a substantial reduction of fakes
Straw Trigger Table - Projected L2 Rates
Straw Trigger Table - Projected L2 Rates
~75% of bandwidth at 3x1032 cm-2s-1
No room for B & some of new phenomena~30% of bandwidth at 3x1032 cm-2s-1
Studying further improvement
Triggers for W, Z, Top, WH, ZH, HWW, SUSY (partial), LED, Z’
without XFT upgrade with XFT upgrade
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66%34%
hours
Inst
. Lu
min
os
ity
(E32
)
Peak Luminosity = 3E32
Typical Projected Store Evolution