15/11/2004NIKHEF SAC, Sijbrand de Jong 1 DØ Report NIKHEF SAC meeting 15/11/2004 (report for internal use only) Sijbrand de Jong Tevatron performanceTevatron performance DØ hardware statusDØ hardware status Physics with DØPhysics with DØ Transition to ATLASTransition to ATLAS

15/11/2004NIKHEF SAC, Sijbrand de Jong 2 Tevatron Past Performance

15/11/2004NIKHEF SAC, Sijbrand de Jong 3 Tevatron Future Performance 1.Electron beam cooling (being installed now, commissioning next year) 2.Slip stacking at p/pulse every 2 seconds 3.Increase pbar production aperture by 25% 4.Increase stacking rate at small stacks 5.Mixed pbar operation, the recycler starts to pay-off + many small improvements

15/11/2004NIKHEF SAC, Sijbrand de Jong 4 Tevatron Performance future

15/11/2004NIKHEF SAC, Sijbrand de Jong 5 Tracking Status Overall very stable over past year. Concerns: 1.17% of SMT dead (~ random regions) 2.1% channel loss in CFT (in VLPC cassettes) 3.Tracking software performance (pattern reco & speed) Radiation damage expected for >5 fb -1 New L0 will cover (and even improve) Inner circle is size of golfball NIKHEF contribution to SMT construction and radiation monitoring

15/11/2004NIKHEF SAC, Sijbrand de Jong 6 Calorimetry and Muon System Status Intermittent noise problems in calorimeter: Hot patches, Rings of fireHot patches, Rings of fire Noise hunt pays off:Noise hunt pays off: Found whole bunch of dead-shorts (metal washers instead of G10) First indications of reduced noise sensitivity Muon system performance efficientMuon system performance efficient and very stable and very stable NIKHEF contribution to muon reconstruction

15/11/2004NIKHEF SAC, Sijbrand de Jong 7 Forward Proton Detector Commissioned and operated stand-alone Soon to be operated routinely in DØ DAQ  =  p/p distribution NIKHEF contributed Roman Pot thin windows and castles

15/11/2004NIKHEF SAC, Sijbrand de Jong 8 Trigger and DAQ DAQ can handle bigger rates than foreseen (after extensive work) Read-out dead time of SMT limiting 1 st level trigger Trigger needs additional functionality to cope with higher Luminosity and to allow lower thresholds, e.g. on jets Trigger upgrade is proceeding to plan 2 nd level Silicon Track Trigger has been commissioned NIKHEF contribution to STT

15/11/2004NIKHEF SAC, Sijbrand de Jong 9 Reconstruction & MC Reconstruction improves continuously All data has been reprocessed (with p14) to physics quality (20% off-site) All data will be reprocessed again (with p17) to improve physics quality(100% off-site) >10 9 events to be processed Processing speed crucial(need to improve significantly) GRID usage essential MC producing about 10 6 events per week (world-wide) (e.g. at NIKHEF fully gridified)

15/11/2004NIKHEF SAC, Sijbrand de Jong 10 DØ Data taking efficiency Highest efficiency day had 2/3 NIKHEF DAQ shifters in charge

15/11/2004NIKHEF SAC, Sijbrand de Jong 11 QCD inclusive jet cross section

15/11/2004NIKHEF SAC, Sijbrand de Jong 12 bb production mechanisms Measured Pythia expected Measured Pythia expected FCR (62±6±9) % (47±5) % GSP (21±7±18) % (43±5) % FEX (18±11±21) % (10±3) % Bram Wijngaarden thesis nearly finished

15/11/2004NIKHEF SAC, Sijbrand de Jong 13 EW Z  l + l - Tau: thesis Silke Duensing work continued by Cristina Galea OS-SS

15/11/2004NIKHEF SAC, Sijbrand de Jong 14 EW W  l EW W  l M T =  p e p (1-cos  e )

15/11/2004NIKHEF SAC, Sijbrand de Jong 15 W width  W =2.011   GeV PDG:  GeV PDG:  GeV

15/11/2004NIKHEF SAC, Sijbrand de Jong 16 WW, ZW, W , Z  ll :  (pp  WW)= (14  4) pb lll:  (pp  ZW)< 15 pb l  :  (pp  W  )= (181  64) pb ll  :  (pp  Z  )= (116  17) pb All in All in good agreement good agreement with SM with SM

15/11/2004NIKHEF SAC, Sijbrand de Jong 17 Z  bb Trigger: L1:  + jet(E T tower >5GeV) offline selection: 2 jets, E T >15GeV, back-to-back offline selection: 2 jets, E T >15GeV, back-to-back Problem with turn-on curve for jets ! Still working on this ! Axel Naumann thesis in the works Not yet reliable

15/11/2004NIKHEF SAC, Sijbrand de Jong 18 new charm hadron X  J/   +  - m X =3872  4 GeV (Belle has  0.8 GeV) Width 17  3 MeV

15/11/2004NIKHEF SAC, Sijbrand de Jong 19 The bottom line  b )=(  0.04) ps -0.18

15/11/2004NIKHEF SAC, Sijbrand de Jong 20 B 0 d lifetime 2D-fit in mass and lifetime Background lifetime is mass Dependent ! Signaltemplate Backgroundtemplate Thesis of Paul Balm (defense 8 Dec 04)

15/11/2004NIKHEF SAC, Sijbrand de Jong 21 B 0 s lifetime  (B s )=  ps  (B s )/  (B 0 )= 

15/11/2004NIKHEF SAC, Sijbrand de Jong 22 Excited bottom hadrons B**/B J B  resonances m B1 =5724MeV m B2* =5748MeV

15/11/2004NIKHEF SAC, Sijbrand de Jong 23 BcBcBcBc J/   X final state m(B c )=5.95  0.37 GeV  (B c )=0.45  0.17 ps

15/11/2004NIKHEF SAC, Sijbrand de Jong 24 B 0 d mixing B s mixing in the works Final state flavour: sign  in B  D*  X 3 methods of initial state flavour tagging: Opposite side soft muon:  m d =0.506   ps -1 Same side fragmentation pion:  m d =0.488   ps -1 Comby of above two + same side jet charge:  m d =0.456   ps -1

15/11/2004NIKHEF SAC, Sijbrand de Jong 25 tt  l+ +4 jets Single tag Double tag CSIPSVT e channel in thesis of Lukas Phaf (cum laude)

15/11/2004NIKHEF SAC, Sijbrand de Jong 26 tt  e  +2 +bb S:N=70:1

15/11/2004NIKHEF SAC, Sijbrand de Jong 27 tt  e  jets event

15/11/2004NIKHEF SAC, Sijbrand de Jong 28 tt  e  jets event

15/11/2004NIKHEF SAC, Sijbrand de Jong 29 tt  6 jets cut cut >= 1 SVT tag Thesis of Freya Blekman (expected soon)

15/11/2004NIKHEF SAC, Sijbrand de Jong 30 Top cross section and mass Biggest problem: jet energy scale

15/11/2004NIKHEF SAC, Sijbrand de Jong 31 Single top production Measured Br(t  Wb)/Br(t  Wq)=0.70  0.26  0.11 (SVT) CSIP+SLT SVT+SLT Final state l b  (single top)<23 pb (95%CL) BGestimationsamples Theoretical work in Thesis Lukas Phaf

15/11/2004NIKHEF SAC, Sijbrand de Jong 32 SM Higgs WH  e bb: H  WW  l l : Based on ~200 pb -1 : Luminosity increase  30 expected Combine CDF and DØ: sensitivity  2 Optimise detector calibration, trigger, analysis:  ? More channels (e.g. H   +  - ):  ?

15/11/2004NIKHEF SAC, Sijbrand de Jong 33 Doubly charged Higgs H ++ H --   +  +  -  -

15/11/2004NIKHEF SAC, Sijbrand de Jong 34 SUSY, neutralinos

15/11/2004NIKHEF SAC, Sijbrand de Jong 35 SUSY, squarks and gluinos Signal prediction: SUGRA m 0 =25GeV, A 0 =0, tan  =3  <0 squark/gluino decay into quark/(qq pair) + neutralino

15/11/2004NIKHEF SAC, Sijbrand de Jong 36 (Large) Extra Dimensions Looking for  (M s >1.36 TeV) and ee/  (Ms>1.1 TeV) resonances (next slide) Jets+E T mis : M s >0.7 TeV

15/11/2004NIKHEF SAC, Sijbrand de Jong 37 NIKHEF participation in DØ staff PhD students Post-docs Jul 98 Jul 99 Jul 00 Jul 04 Jul 05 Jul 06 Jul 07 Jul 08 Jul 09 Jul 03 Jul 02 Jul 01 NOW

15/11/2004NIKHEF SAC, Sijbrand de Jong 38 Towards ATLAS GRID tests under realistic conditions NIKHEF plays very active role in DØ GRID deployment Hadron collider physics analysis background Experienced staff on ATLAS Creating interest in hadron collider physics Positive atmosphere for ATLAS

15/11/2004NIKHEF SAC, Sijbrand de Jong 39 Summary Tevatron luminosity looks promising (after slow start)Tevatron luminosity looks promising (after slow start) DØ is getting into shapeDØ is getting into shape Calibration at physics paper level and improvingCalibration at physics paper level and improving Ten’s of papers submitted this yearTen’s of papers submitted this year NIKHEF has significant contributionNIKHEF has significant contribution High profile analyses:bottomHigh profile analyses:bottomtoptau Transfer of knowledge (GRID,…)Transfer of knowledge (GRID,…) and experience (people,…) to ATLAS

15/11/2004NIKHEF SAC, Sijbrand de Jong 40 Conclusion Up to you !