Scanning Z->ee Candidates

1. Scanning Z->ee Candidates • Poor Man’s Picked 88 candidates (/usrdisks/714/fnal_3/diehl/run2/zeesearch/zstrip/stripped/all*.raw) • Used D0ve_alldis to look at event display pictures. • Classified the events. • It’s not so easy to tell photons from electrons in this data. • I’m not very good at divining the difference between highly EM jets and photons, for that matter. Tom Diehl Oct 02, 2001

2. Comments on Z Scan • Categories: • Only 2 Nice isolated Central EM clusters 16 • 2 EM clusters “seems OK” 19 • Jetty/Metty/or lots of SVX hits in EM cluster direction (includes many events with a forward EM) 28 • Forward EM & Not Jetty/Metty 15 • Other (hot cell events dominate display) 10

3. “Jetty Event” • Blow up the tracker view:

4. A Matching CFT track • CFT track with Et/Pt=0.48

5. CFT & SMT Tracks • Interesting data sample.

6. 2 SVX tracks match in phi view • Many of the EM clusters have SVX tracks which point at them. Cal M(ee)=71 GeV/c2

7. Summary & Plan • Sure looks like this is the Z to ee. • Finish up the T1.56 root files • tapouts • pickevents - try out new picker • finish the La Granda Macchina data sets • La Granda Macchina • working on technical issues such as tapping out W and Z samples in same crank of the gears • Take advantage of new RecoVersion when becomes available • Make better use of the SMT, SMT&CFT, and CFT tracks • Muons

8. WZ Groups W & Z Search • What we did after we selected the events: • Poor Man’s Pick Events: SAM & Copyd0om • runreco (see d0tools) • runrecoanalyze (see d0tools) • d0ve_alldis • Results • Missing ET • Scanning • Summary & The Plan Instructions on WZ web page Tom Diehl 09/28/01

9. Update Database Event Selector Get_file_Link La Macchina All Reco’d Runs in SAM 1 Key: Input Product WZ Run & Event Database (Web-based) “WZ_catchup” PRJ disk of Links to SAM cache Run Text File 2 3 “Tapped-out” Events for analysis Missing Gear is Pick Events

10. Drell-Yan • 1999 PRL from CDF • M(ee) is in a minimum @ 60 GeV/c^2

11. “W Candidates” • Event Selection: see Marco’s slides • I used the SAM Browser and data access methods, Get_file.py, & CopyD0om.py to extract the 121 events and put them in a directory. • Temporary location: d0mino /usrdisks/714/fnal_3/diehl/run2/zeesearch/wstrip/stripped/all*.raw Z Candidates will be in ...zstrip/stripped/all*.raw before the end of tomorrow.

12. Missing ET • “MinBias Events” Run 131974 Prior to Hot Cell Killer Hot Cell Killer Applied MET MET Hot Cell Killer More Hot Cell Killer MET MET G. Bernardi made these plots using “NADA” Warning: some of ECN HV unplugged for some time

13. Missing ET • “W Candidates” Prior to Hot Cell Killer Hot Cell Killer Applied MET MET Hot Cell Killer More Hot Cell Killer MET MET G. Bernardi made these plots using “NADA” Warning: some of ECN HV unplugged for some time

14. Scan the Events (d0ve_alldis) • Observations • scanning was very helpful in understanding what was going on in these events • candidates were mostly dijets • MET direction and magnitude not shown in the scan display • Results from 121 W-candidates • 20 events are “W-like” • 22 events are “weakly W-like” • 75 events were clkearly dijets or “jetty” • 4 events weren’t classified

15. Dijet Examples

16. W-Like Example

17. W-Like Example

18. Candidate Z->mm Event Reminder: We must turn our attention to muons ASAP.

19. Summary & The Plan • Looks like Z’s and W’s to electrons with ~1/2 energy scale but we haven’t proved it • so Run La Macchina and accumulate our W and Z to electron(s) candidates • improve our use of tracking information • MET in the selection? • Use preshower and other detectors • Muons • this is a big hole in our operation and we must get on this asap.

20. END of Presentation Beginning of storage slides

21. Data Analysis • La Granda Macchina is producing tapped-out root-tuples and raw data samples for you to study. • You have been receiving email about them & • Julie will tell you all about the progress.

22. Agenda • News: Tom & Georg • La Granda Macchina: Julie Torborg • W & Z to Electrons: Marco Verzocchi • More W & Z to Electrons: Tom Diehl • Electrons in Data: Ming-Cheng Gao • MC Requests & Card Files: Georg Steinbrueck • AOB & Around the Room

23. Triggers & ORB • Ask Amber/Alan • Dimuon Trigger has been implemented in the central region (unprescaled?) • L3 filter applied on some calorimeter triggers & soon close to ready for muons • but what’s the strategy and how can we contribute to a sensible approach?) • Ask Andrew • More disk will be available soon? • Coherency of WZ group plan • can the universities in WZ group pool resources? • if Clued0, can we all access the resources?

24. News • WZ put in for a bottle of wine for the first electron with a CFT match. • Looked in Charged_Particle bank • ET(EM) = 26 GeV/c M(ee)=52 GeV/c2 • Found CFT track, E/p=0.95 - go figure.

25. Another Electron • Characteristics: • ET(EM) = 20 GeV/c M(ee)= 44 GeV/c2 • Found CFT track, E/p=0.48

26. WZ RunDatabase WZ Preselection Candidates (SAM Projs) RECO eventually WZ Objects Data Analysis Plan • W/Z group is going to continue to look at each collider run. • RECO does, uh, RECO. • W/Z preselection based on leptons • Database has run by run stats (J.K.) • Get Candidate Events • Develop W/Z objects

27. Electron • Looked in Charged_Particle bank • ET(EM) = 26 GeV/c M(ee)=52 GeV/c2 • Found CFT track, E/p=0.95

28. Bad Electron Candidate? • Looked in Charged_Particle bank • ET(EM) = 15 GeV/c M(ee)= 35 GeV/c2 • Found CFT track, E/p=1.2 but it’s not the closest track

29. La Macchina • Event Selector uses • Standard very loose object-ID based event selection • so far only on electrons with purpose of getting a Z sample • Event Selector (gear #2) Runs on • Root-tuples produced by Reco • Plan to Adapt to whatever is the best small reco output • Done • All 3 gears have been turned • We’ve run on all of the Reco 1.56 Output & at present we are iterating gear #2 on that sample • Not Done • Plan to start turning gear #3 when we get satisfied with the result of gear #2. • We’ve got no interface to “Pick Events” which is, for time being, non-existent