# Presentation: 265582

## 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

## 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

## “Jetty Event”

- Blow up the tracker view:

## A Matching CFT track

- CFT track with Et/Pt=0.48

## CFT & SMT Tracks

- Interesting data sample.

## 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

## 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

## 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

- Tom Diehl
- 09/28/01

- Instructions on
-  WZ web page

## La Macchina

- Key:  Input  Product

- WZ Run & Event
- Database
- (Web-based)

- All Reco’d
- Runs in SAM

- “WZ_catchup”
- PRJ disk of Links
- to SAM cache

- “Tapped-out”
- Events for analysis

- Run Text File

**1**

**2**

**3**

- Missing Gear is
- Pick Events

## Drell-Yan

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

## “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.

## Missing ET

**Missing E****T**

- “MinBias Events”  Run 131974

- Prior to Hot Cell Killer

- Hot Cell Killer Applied

- Hot Cell Killer

- More Hot Cell Killer

- MET

- MET

- MET

- MET

- Warning: some of ECN HV unplugged for some time

- G. Bernardi made these plots using “NADA”

## Missing ET

- “W Candidates”

- Prior to Hot Cell Killer

- Hot Cell Killer Applied

- Hot Cell Killer

- More Hot Cell Killer

- MET

- MET

- MET

- MET

- Warning: some of ECN HV unplugged for some time

- G. Bernardi made these plots using “NADA”

## 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

## Dijet Examples

## W-Like Example

## W-Like Example

## Candidate Event

- Reminder: We must turn our
- attention to muons ASAP.

## 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.

## END of Presentation

- Beginning of storage slides

## 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.

## 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

## 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?

## 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.

## Another Electron

- Characteristics:
- ET(EM) = 20 GeV/c     M(ee)= 44 GeV/c2
- Found CFT track, E/p=0.48

## 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

## Electron

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

## 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

## 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