D0 Collaboration Meeting

1
Central Muon Scintillators

• Steven Doulas
• D0 Muon Upgrade Group
• Northeastern University

2
Group Effort

• D. Hedin, S. Dychkant
• NIU
• V. Bodyagin
• Moscow State U.
• H. Mao
• China
• L1Muon- K.Johns, R. McCroskey, J. Temple
• Arizona U.
• T. Diehl, A. Ito, L. Stutte, M. Zanabria
• FNAL
• A. Bannanjes, S. Bheesette, S. Dugad, N. Mondal
• Tata Institute

3
L1MUO Singles Rate
Collisions
A-layer (all Octs.) 158kHz
No Collisions
A-layer (all Octs.) 69 kHz
4
L1Muo Singles Rate
Collisions
C-layer (all Octs.) 1.15 MHz
No Collisions
C-layer (all Octs.) 1.07 MHz
5
L1Muo Singles Rate
D0 Luminosity 2.9E30 Beam Energy 978.5 GeV
Collisions
No Collisions
6
Why? And how to fix this.

• Activated ceiling w/1MeV gamma
• Need to determine how close to MIP in order to
  discriminate.
• Correct thresholds must be set without cutting
  into efficiency.
• Possible Solutions
• Shielding
• During the Supervised Access, planning to add Pb
  on C-layer counters and measure rates, etc..
• Must take PMT calibration runs using LED Pulser
• We have PMTCALIB package to determine gain and
  p.e.s.
• Adjust thresholds and possibly HV as necessary.

7
PMTCALIB
Gaussian Fit to LED Signal in a typical
C-layer PMT.
8
Gain Measurements
Calculated PMT Gain for different LED light
intensities (overall range is a factor 2)
9
Photoelectron Yield
Photoelectron estimates as a function of PMT
Voltage for counters on PDT243
10
D0ve-Muon Event Display
11
D0ve-Muon Event Display
12
D0ve-Muon Event Display
13
Central Muon Trigger (A.C)
14
Central Muon Trigger (A.C)
15
Central Muon Trigger (A.C)
16
CM(A.C) L1Cal 5GeV Jet
17
CM (A.C) L1Cal 5GeV Jet
18
CM (A.C) L1Cal 5 GeV Jet
19
CM (A.C) L1Cal 5Gev Jet
20
CM (A.C) L1Cal 5GeV Jet
21
Goal A Central Muon Scintillator(only) Trigger

• In Summary
• Shielding
• Collecting and analyzing raw data calibration
  data.
• Use L1Muo CalJet trigger to set muon timing in
  counters.
• Future w/PDT segments
• Thresholds, HV, etc..
• Adjust Beam Delay then position reduce central
  scintillator trigger gate.
• Add TOF gate