1. HCAL Configuration Issues
Drew Baden
University of Maryland
Jeremy Mans
University of Minnesota
13-Oct-18
HCAL TPG

2. HCAL Pulse Nominal HCAL pulse spread over several 25ns buckets
Fraction in bucket is tunable via clock phase adjustment
Need to recover “event” concept, associate energy to a single crossing (bucket) and report it to the trigger
TPG, trigger primitive
13-Oct-18
HCAL TPG

3. FE/DAQ Electronics DAQ S-Link: 64 bits @ 25 MHz READ-OUT Crate
Trigger Primitives
READ-OUT Crate
CAL
REGIONAL
TRIGGER
Rack CPU
SBS
CLK D C H T R H T R H T R
12 HTRs per
Readout Crate,
2 DCC
16 bits
@ 80 MHz
TTC
32 bits
@ 40 MHz
FRONT-END
RBX
Readout Box
(On detector)
HPD
Shield
Wall
QIE
CCA
QIE
GOL
QIE
CCA
QIE
Fibers at 1.6 Gb/s
3 QIE-channels per fiber
GOL
QIE
CCA
QIE
FE MODULE
13-Oct-18
HCAL TPG

4. References HTR (Hcal Trigger Receiver card) Trigger TDR CMSSW
Trigger TDR
(all CMS TDRs)
CMSSW
13-Oct-18
HCAL TPG

5. TPG HTR firmware job: Convert raw QIE format to ET
Linearize, sin(q), ped subtraction all via LUT
Peak detection to associate energy with BX
“Feature bit” (MIP for m in HB/HE/HO, “thin jet” for HF)
Compress into format for Level 1
Transmit to mezzanine card which transmits to RCT
13-Oct-18
HCAL TPG

6. TPG Issue There are 3 main issues: Need to simulate
Peak detection using sum of 2 time slices or not?
Threshold suppression for L1 data
Feature bit?
Latest proposal from Dasu
Need to simulate
Optimize for jets or MET?
MET issue vs Luminosity (pileup)
Which bucket? Does it matter?
13-Oct-18
HCAL TPG

7. Simulation Check… Make sure it’s still ok, and what we are doing works
Check for single vs 2 time slices
Make this plot but use the “rechit”
HCAL TPG
ET “real” (from GEANT)
13-Oct-18
HCAL TPG

8. DAQ Data (Precision Readout)
DAQ path must read out data with zero suppression
Current scheme: ZSP based on TPG associated with that bucket
TPG threshold is in ET…pedestal is E.
Need to simulate how best to do this
13-Oct-18
HCAL TPG

9. DAQ Path (cont)
Chris Tully (JET/MET) requests some information added in HF to quantify instantaneous luminosity
This will help the JET constant term correction due to the underlying event
How best to do this? Need simulation
13-Oct-18
HCAL TPG

10. What Exists in CMSSW? Digitizations (QIE simulation) are there now
Produces un-zero suppressed digis
A “digi” is what is in the DAQ data format (“L2spy fifo” in HTR terminology)
Some ORCA code to do the TPGs but its hard coded with no parameters
Some Trigsim code in ORCA but out of favor with Dasu…
TPGs will be read in by Trigsim (which does NOT exist at this time in CMSSW)
TPG compression LUT (in the HTR) is NOT independent of what is done in the RCT (Trigsim is simulating this)!
Need to be able to use REAL LUTs
Samples?
13-Oct-18
HCAL TPG

11. Who? HCAL digis Trigsim TPG generation Zero suppression Event samples
Rick Wilkinson (Caltech all digis for HCAL
Trigsim
Dasu etal
TPG generation
Rick Wilkinson
Zero suppression
noone
Event samples
Geometry in old simulation is wrong, need new data
Chris Tully etal from JET/MET
Need to wait for CMSSW validation of the new simulation
CMSSW in general
Avi, Jeremy Mans…
HCAL hardware
Drew Baden Jeremy Mans Tullio Grassi
13-Oct-18
HCAL TPG