CSC L1 Trigger Rate

1
CSC L1 Trigger Rate
2-station tracks
3-station tracks
L1034
Better handle on rate reduction with 3-station
pT measurement
CMS Note 2001/033
2
L1 CSC Efficiency vs. Eta
2 ME Stations
3 ME Stations
Can recover a hole in acceptance with ME4/2 and
3-station trigger requirement
CMS Note 2001/033
3
L1 Efficiency 90 LCT Efficiency
Single ? 3ltpTlt100
2 ME Stations
3 ME Stations
If backgrounds reduce LCT efficiency, loss of
redundancy results in lower L1 efficiency
No ME 1/1a
No ME 4/2
4
Pt Misassignment from Muon Bremsstrahlung

• Redundancy with ME4 improves high PT efficiency
  at L1
• We can eliminate bad LCTs by adding some simple
  trajectory cleaning logic in the L1
  Track-Finder
• For Example
• If Df13gt Df12 AND
• Df23gt Df24 AND
• Df13gtthreshold,
• ? should drop ME3 segment from track and use
  (Df12, Df24) for PT assignment.

ME1 ME2 ME3 ME4
X
X
X
X
B. Scurlock
5
TeV m Pt Assignment ME4/1 Study

• Plot Level-1 trigger efficiency for PT300 GeV
  (P1 TeV) muons to pass tight (3-station) CSC
  T-F requirement for adequate rate reduction.
  ME4/1 does recover efficiency.

With ME4/1 AND AU Corrections
Without ME4/1
Ptgt14Ptgt20Ptgt30
Ptgt14Ptgt20Ptgt30
ME4/2
ME4/1
1.8lthlt2.1 and Ptgt20 With ME4/1 AND AU
Corrections e 87.8, was 74 (No
ME4/1) De/e15.4 !
RPC Limit
Expect similar gains for ME4/2