Calorimeter Timing

1
Calorimeter Timing
Detector PreAmp-Boxes

• timing w.r.t accelerator
• done during 1?8 strores

jumpers/ BLS crate 5ns
cable length fixed
sampling time by RF-bucket in FPGA
MCH ADC cards
Platform BLS cards
delays/ trigger tower
MCH Timing Control Boards
MCH Trigger boards
scl-cable length adjustable 10ns
MCH Trigger framework
2
Cal Timing L1 timing

• Verification of cable between from Detector to
  Trigger Summers (BLS-boards) CC uniform
• ECN, ECS different regions
• cable from trigger summers to trigger receiver
  boards (MCH)
• 3 different lengths (ECN, CC, ECS) same as in
  Run I
• finer adjustment for different EC regions
• adjustment possible for each trigger tower with
  delay line

em
3
Trigger/Read Out timing

• flash ADC Read Out adjusted to peak of the
  Trigger Pickoff
• measurements done for a sample of em/had channels
  in CC
• same value used everywhere

• systematic adjustment comparing L1Cal-Read Out
  by varying the Trigger by /- 1 RF-bucket
• final L1Cal trigger Read Out needed

4
Timing Studies triple sampling
?
?
?
Triple sampling runs comparison of energy
measured at the nominal position, 132ns
earlier/later

• ratios allow to determine time offset
• more precise timing from comparison with Spice
  model

5
Timing Model Validation
Model validation comparing pulser calibration
signal with Spice Model
Measurement
Simulation
em
Model optimisation pulse reflexion
measurements on the detector
had

• verification underway

6
Timing cryostat comparison
ECN
CC
early/ nominal
late/ nominal
ECS
after 1st adjustment from scope measurements 3
cryostats and all crates show essential the
same behavior !
7
Timing Studies delay scan
97 ns
113 ns
81 ns
?0.64
?0.61
?0.39
?0.69
early/ nominal
?1.04
?0.82
?0.77
?0.78
late/ nominal

• at first look an offset of 113 ns seems correct

8
Status Outlook

• yesterday
• new FPGA code, with 6 RF-buckets shift (113 ns)
• analysis of triple sampling data underway
• Spice Model validation
• extraction of time-offset from comparison with
  Spice Model
• separation of measurement with different
  PreAmp Types
• Fine Adjustment for each Quadrant
• October shutdown(?)
• fine adjustment for each BLS crate?
• Trigger/Precision Read-Out comparisons a.s.a.p