1 / 14

W/Z Plan For Winter Conferences

W/Z Plan For Winter Conferences. Tom Diehl FNAL @ Saclay 12/2001. W/Z Group’s Charge. Goals for spring conferences: Z -> mm (ee) Mass & Cross Sections W -> mn (e n) Transverse Mass and Cross Sections W -> mg (e g ) Event Displays

melvina
Download Presentation

W/Z Plan For Winter Conferences

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. W/Z Plan For Winter Conferences Tom Diehl FNAL @ Saclay 12/2001

  2. W/Z Group’s Charge • Goals for spring conferences: • Z-> mm (ee) Mass & Cross Sections • W-> mn (en) Transverse Mass and Cross Sections • W->mg (eg) Event Displays • My take on these goals: Selected because they demonstrate that the upgraded detector is shaping up: • Show that the new muon detectors and trigger will do their jobs • It’s Most important that we demonstrate the capabilities of the new central tracker.

  3. W/Z Group’s Charge • Ambitious • We will achieve the results in the electron channels with O(100’s) of events. • Muons are more challenging because we’ve been limited by the trigger bandwidth and because the CFT trigger is late. • Z->mm definitely, maybe W->mn • Use the Tracker! Why? • Z’s and W’s are cleaner. • pT resolution is much better than the rest of the muon detector • We will be using it in the long run We should learn to use it now.

  4. WZ Group’s Plan • Data Collection: • WZ_Reco (see Georg’s talk) • La Macchina (Selecting from Reco_S events) • Efficiency Calculation • The plan - what we are doing: • I wrote down some equations - shows my bias for using the tracker in the selection • Background Estimate • Examples

  5. Efficiency For W’s Efficiency For Z’s Efficiency Calculation • Partly from Monte Carlo. • Monte Carlo calculates acceptance & kinematic selection • Monte Carlo doesn’t model the detector performance • Partly from Data • Use Data whenever possible • See above in reverse for Data

  6. Efficiency Calculation • “Loose” is fraction of signal which passes the “Loose” selection criteria in MC. • “Tight” is efficiency of “Tight” cuts w.r.t. “Loose” cuts. • 5 components • Take care that all of “Loose” is in the denominator • Take care: there are several ways for one muon to be reconstructed as two or more • The multiple NSEG thing • Multi-region muons

  7. Efficiency Calculation • For W’s, “Trigger” is efficiency of L1 for a single “Tight” muon • For instance, compare the number of events with a reconstructed “Tight” muon that pass the MU-EM trigger with the number of those that pass the 1-EM trigger • With any kind of luck there will be a L3 component to this with an efficiency close to 1.0 • For Z’s, “Trigger” is a little more complicated because it involves “Tight” and “Loose” muons: • “Loose” allowed us to miss an A or BC scintillator hit • so it’s not quite “Trigger2”

  8. Efficiency Calculation • “Track” is probability to reconstruct and match the gtrk • Has anybody tried this? • “Isolation” is the probability for a muon from W or Z to be isolated. • Monte Carlo doesn’t yet model delta-phi very well so we have to get this from the data. • For instance, select events with two isolated high pT central tracks, two tight muons, and at least one isolated one isolated muon. Look at other muon. • Definition of Isolation:

  9. W/Z Group MC Requests • Muon-Relevant Samples • 50,000 W-> mn • 20,000 Z/g*-> mm • 10,000 W-> tn (all channels) • 10,000 Z/g*-> tt (all channels) • Characteristics • Pythia Generated • Geant Version • Plate-Level Simulation • Most Recent D0Gstar Geometry (including CF Bottom B-layer PDT rotation fix) • Zero extra interactions • Reco’d with p10.13 or later

  10. W Backgrounds • Combinatoric & Cosmic • Small if CFT is used? Prove it. Hint: Use Cosmic Ray Runs. • W->tn+X->mnnn+X • Get this from the MC with a similar calculation used to measure the efficiency. • Muons from heavy quark decay • Determine this from the data. The background: Jets are away or too low ET

  11. 0 Tags 2Tag 1Tag IsolTagged (Don’t look at jets) W->mn Bkgd. Setup

  12. 2Tag 1Tag IsolTagged (Don’t look at jets) W->mn Backgrounds • With events that pass same trigger, muon ID criteria, etc … • 3 Samples (Using 1/2 detector as Tagged-Side) Keeping track of sides, you can get 2X more stats than this.

  13. Z Backgrounds • Combinatoric & Cosmic • Small if CFT is used? Prove it. Hint: Use Cosmic Ray Runs. • Z->tt+X->mmnnnn+X • Get this from the MC with a similar calculation used to measure the efficiency. • Muons from heavy quark decay • Determine this from the data as with the W’s.

  14. Summary • Goals for spring conferences: • Z-> mm (ee) Mass & Cross Sections • W-> mn (en) Transverse Mass and Cross Sections • W->mg (eg) Event Displays • My take on these goals: • Show that the new muon detectors and trigger will do their jobs • It’s Most important that we demonstrate the capabilities of the new central tracker.

More Related