ECAL DPG
P. Meridiani
CMS Italia
13/02/2007
Paolo Meridiani - INFN Roma1
1
Outline
 ECAL
Achievements in the 2006
 Task
list & organization of the new
ECAL DPG
Paolo Meridiani - INFN Roma1
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Achievements in the 2006

From June 2006 ECAL community has been splitted into several
experimental setups
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TB @ H4 (ECAL)
TB @ H2 (ECAL + HCAL)
Cosmic setup
MTCC
Several achievements in different technical areas

Full transition to CMSSW:
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•
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P. Meridiani, A. Ghezzi
LocalReco
F. Cossutti, C. Rovelli
Simulation
F. Cavallari, S. Rahatlou
DB
G. Della Ricca, F. Cossutti, B. Gobbo, A. Ghezzi
DQM
DAQ & Trigger firstly integrated and validated
Laser operations towards final setup
Italian contributions has/will been/be flagged
Paolo Meridiani - INFN Roma1
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H4
4 periods, from July 24th to Nov 12th, for a total of
~70 days of data taking, 6300 runs, ~ 2 billions electrons
To summarize:
 First goal:Intercalibration (9 SM (1 twice), 1/4 of EB))
 Energy Scan & linearity (15-250 GeV, in M1, M3, M4 and as function
of eta)
 Gap & cracks, corners & edges
 Xtals Monitoring and Laser operation
 Irradiation (5 Xtals)
 Trigger primitives
 Zero suppressions
 Synchronous running
 Muons
Paolo Meridiani - INFN Roma1
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Intercalibration at H4 [1]

9 SM put on the beam, of which one repeated twice

Better than what expected considering that beam arrived with 1 month
delay
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At regime intercalibrating 1 SM (1700 xtals) took less than 2 days

Different intercalibration methods tested: intercalibration using the
single crystal response
All 9 SMs
Corrected single crystal response
Intercalibration reproducibility 5x5 resolution at 0.7%
in a two months period (SM22) @ 120 GeV
Paolo Meridiani - INFN Roma1
A. Benaglia, P.Govoni, A. Martelli, M. Paganoni, D. Riparo, R. Salerno, V. Tancini
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Intercalibration at H4 [2]
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In situ intercalibration methods: based on the energy
reconstructed in a cluster (typically 5x5)
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Different techniques can be used to evaluate single crystal
intercalibration (matrix inversion, iterative algorithms)
Performances
compatible w.r.t.
single crystal
intercalibration
A. Benaglia, P.Govoni, A. Martelli, M. Paganoni, D. Riparo, R. Salerno, V. Tancini
Paolo Meridiani - INFN Roma1
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Energy/position resolution, noise

Analysis is still on going

Basically a confirmation of the 2004 results, where most of
the details of the amplitude reconstruction were understood
Energy resolution in 3x3 using 3+5 weights
Noise in ADC counts
Preliminary
Preliminary
C. Rovelli
Paolo Meridiani - INFN Roma1
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Tuning the MC

More effort has been put on MC validation/tuning/comparison w.r.t
2004. Last possibility to tune MC before CMS
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In particular
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Lateral containment
Using both G4.7 & G4.8 shower is
1% broader in sim (looking at
E1/E25)
Situation is reversed w.r.t G4.5 (1%
narrower sim), change seems to be
due to variation in the
implementation of multiple
scattering
Relative variation with  and  are
instead very well reproduced
On going work together with G4 developers to understand/correct
discrepancies
F. Cossutti, C. Rovelli, P. Meridiani
Paolo Meridiani - INFN Roma1
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Dead channel correction
H4 data can also be used to evaluate dead channel corrections
 Main idea is to measure in the data the correlation between the energy content
of the non-functioning channel with the channels in a 5x5 crystal matrix:

Correlation functions depend on the ,  of the crystal,
particle’s energy and impact position
Simple approach and more refined (neural net) have been explored. Both seem
to work fine
Corrections being
implemented as a
standard CMSSW
module
Also map of
noisy/dead channels
being implemented in
Offline DB
Paolo Meridiani - INFN Roma1
S25reco_corr/S25reco Resolution (%)

Energy (GeV)
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25ns bunch structure
A 25-ns bunched beam was delivered for 10 days (end of
september) to H4:
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Accelerator clock and orbit signals received by a LHCrx
module and distributed to CCS/DCC/TCC via the TTCci.

Trigger Primitives acquired and TCC data written in the
event. Used to validate CMSSW TPG emulator
The 25 ns beam sub-structure as seen from
H4 TDC.
Paolo Meridiani - INFN Roma1
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H2
Lots of data with different beams (e, - , - on target) with E (1300GeV)
More difficult experimental condition environment with respect to H4
For example ECAL temperature is not as stable as H4
Also beam contamination: delicate beam cleaning/particleId required for all
analysis
Paolo Meridiani - INFN Roma1
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ECAL intercalibration @ H2

Intercalibration methods used at H4 have been adapted for H2
running
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Temperature variations (±0.1C) (corrections needs to be applied before
calibration)
Less statistics for each xtal than H4
S1 calibration results
Wider beam
Beam contamination
5x5 resolution @ 50 GeV ~ 2%
Still larger than expected.
After cal.
Before cal.
ADC counts
Paolo Meridiani - INFN Roma1
D. Del Re, R. Paramatti, S. Rahatlou 12
Combining ECAL+HCAL

On going work: optimization of the
combined ECAL+HCAL response

Choosing optimal weights for
combining ECAL + HCAL energies
• E=EECAL+EHCAL
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Different calibration schemas are
being tried in order to optimize
resolution and linearity
Paolo Meridiani - INFN Roma1
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0 run @ H2
Resolution using S1 calibration:
(0) ~ 4.8%
(0) ~ 3.7%
0
0
20GeV beam
Runs taken at 3 energies:
9, 20, 50 GeV
Before calibration
After calibration
Being used to optimize the
pi0 reconstruction/selection
A simple test of the 0
calibration algorithm has
been performed
Paolo Meridiani - INFN Roma1
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D. Del Re, D. Franci, S. Rahatlou
Cosmic Intercalibration

Every integrated SM is/will be tested for
around one week using a specific cosmic setup
(located in H4)
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Useful for two main reasons
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10° inclined SM
APD HV raised to have gain 200
About 5 million triggers are collected for each
SM
Initial commissioning of the integrated SM
Preliminary intercalibration coefficient can be
computed at a precision of around 2% for all
channels
Systematics w.r.t to beam intercalibration are
under detailed study
F. Ferri, A. Ghezzi, S. Ragazzi, T. Tabarelli
Paolo Meridiani - INFN Roma1
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ECAL @ MTCC

2 SMs at 11 o’clock
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Gain 200 (S/B  30 for aligned muons)
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Events with muon signal in ECAL
0.5% of DT trigger
 0.15% of CSC trigger
 Checks with/without magnetic field
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Pedestals/Noise
• Observed variation of the value of the pedestal
but noise is unchanged
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Muon signal amplitude/timing
• Amplitude unaffected, small variation of the
timing (3ns) still under investigation
Paolo Meridiani - INFN Roma1
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DAQ & Trigger
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ECAL DAQ software system:
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In H4 also full DAQ Hardware integration has been achieved
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The ECAL DAQ software system has been used in H4, H2 (HCAL+ECAL) and
MTCC (integrated with Global DAQ & Trigger)
Final H4 test-beam version (release ECAL_0_1_0, based on XDAQ_V3.5.2
and SLC3) has been closed and archived.
Work to port it to XDAQ_V3.7.3, SLC4 /64-bits is in progress.
Full ECAL triplet: CCS, DCC, TCC
MATACQ board: 1-ns sampling of laser pulse for monitoring purpose
TODO:
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Move toward SLC4 / 64-bits
Software system is done to support 36 SMs in EB. To be adapted to include
Endcaps
DAQ and Trigger configuration from DB (tables implemented, but read now
from XML)
Paolo Meridiani - INFN Roma1
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Databases
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The DB and its access tools have been operated at H4 and
H2 test-beams
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DCS Configuration DB (via PVSS) has been tested and works fine.
DCS Condition DB (via PVSS) has performance issues.
DAQ/Trigger Condition DB: run records and DAQ/Trigger
configuration keys are written in the Condition DB. Writing of
summary histograms will be implemented.
DQM (Data Quality Monitor) logging to Condition DB works well.
DCU measurements (APD temperatures+currents, electronics
temperatures, LV settings) are written to Condition DB via C++ API.
Most offline DB objects have been implemented and integrated into
the CMSSW reconstruction
F. Cavallari
Paolo Meridiani - INFN Roma1
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DQM
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ECAL DQM has been widely used in all the setups
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2006 has been spent in continuous update/development/upgrade
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Many useful low level detector tasks have been implemented, used to
spot problems/debug the system
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Some TB physics oriented task have been also developed
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data integrity
pedestal mean/noise
signal pulse shape
laser/test-pulse amplitude & timing response
trigger primitives activity
Cosmics occupancy and energy spectrum
beam energy deposit (max crystal, 3x3 matrix)
beam profiles as measured by hodoscope
energy deposit vs. beam position
To be moved towards the CMS physics
F. Cossutti, G. Della Ricca, A. Ghezzi , B. Gobbo
Paolo Meridiani - INFN Roma1
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An example of a H4 DQM page
F. Cossutti, G. Della Ricca, A. Ghezzi , B. Gobbo
Paolo Meridiani - INFN Roma1
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Laser monitoring
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Laser: needed to track xtal trasparency changes.
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~1300 Laser runs taken in the H4 setup.

This data volume is equivalent to 10 hours of full CMS running
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All data at H4/H2 have been processed ‘quasi-online’ using
the DQM infrastructure. However, this is different from the
online “laser farm” that we’ll need in CMS

Stability : APD/PN ratios for each channel

Overall stability good, even without refined corrections.
 But detailed workflow from laser events to corrections is
still to be demonstrated...
Paolo Meridiani - INFN Roma1
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Laser Monitoring

H4 stability
Stability 1.4 ‰ from gauss fit to peak.
Long tail under
study, but overall
stability is
satisfactory
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H2:
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D APD/PN
In H2 night/day effects are larger (no room with stabilized T).
Anti-correlation between T and APD/PN (~ -2%/°C) as expected.
H2 testbeam:
Black : APD/PN,
averaged over 100
channels.
Red : DT/20+1
Paolo Meridiani - INFN Roma1
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ECAL in-situ calibration: status

Different calibration methods as described in PTDR needs
to be merged into a coherent plan
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Since PTDR: big effort has been put on 0 calibration
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4 internal notes have been produced by different groups
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To exploit full potential these events need to be selected
from L1 accepted events
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Special stream/trigger techniques are being designed
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Additional effort: improve/put calibration in CMSSW.
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2007 should be dedicated to
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Coherent plan for calibration including first year data taking
Definition of detailed workflow
D. Del Re, D. Franci, P. Govoni, M. Paganoni, A. Palma, R. Paramatti, S. Rahatlou, R. Salerno
Paolo Meridiani - INFN Roma1
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Tasks
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DQM
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Amplitude reconstruction
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Coordination and responsible for basic services
Many of the other tasks listed below involve or require DQM
And digitization
DCC operation
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Data unpacking, and Digi to Raw translator; endcap specific mapping issues
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TCC operation
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Trigger Primitives
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Selective Readout Processor
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Emulation
Emulation; algorithm(s) for low luminosity
Synchronization and timing
Paolo Meridiani - INFN Roma1
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Tasks[2]
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Databases
Calibration and alignment
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Calibration methods and algorithms
•
•
•
•
•
•
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Use of “precalibration”
Phi symmetry
0
Z→ee
Z→
Single electron
“low level calibration”
• Pedestals; gain ratios; dead channels
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Clustering
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Crystal transparency corrections (Laser)
Alignment
And cluster corrections
Simulation
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Geometry (new into CMSSW 140)
Shower simulation
Paolo Meridiani - INFN Roma1
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Tasks [3]
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Preshower issues
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Try to integrate the preshower aspects within the other categories
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Event display
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Global performance monitoring
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alias offline DQM
Paolo Meridiani - INFN Roma1
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Sub-boxology
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ECAL framework
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Reconstruction
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Calibration
Laser transparency corrections
Alignment
Low level calibration (pedestals, gain ratios…) ?
Simulation
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Clustering, superclustering and corrections
Calibration and alignment
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Data format, raw data, time frames,amplitude reconstruction, application of
calibration constants
Geometry
Shower simulation (GEANT and FAMOS)
Databases
DQM
Testbeam analysis
Paolo Meridiani - INFN Roma1
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Contacts
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Offline: Reconstruction
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Offline: Simulation
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Overall: to be defined
Alignment: Brian Heltsey
Transparency correction (laser): to defined
Offline: Analysis tools
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Trigger primitives: S. Baffioni
Offline/Commissioning: calibration and alignement
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Overall: Fabio Cossutti (ad interim)
Geometry: Brian Heltsey
Offline: Level-1 trigger
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Low level reconstruction: Paolo Meridiani (ad interim)
Clustering: David Futyan (ad interim)
Requested…
Physics: JetMet

Requested…
Paolo Meridiani - INFN Roma1
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Conclusions

2006 has been a fundamental year for the ECAL project
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10 SM have been intercalibrated with the beam
All integrated SM undergo to cosmic calibration
DAQ + DQM integrated and tested in different setups
First validation of CMSSW Offline software + DB achieved
2007:

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solid base to start from but refinement/completion work is needed
in many areas
Primary goals
• Prepare everything for commissioning
• Deliver a full coherent picture for calibration/corrections

Italian community plays an important role inside ECAL DPG
covering many aspects/tasks
Paolo Meridiani - INFN Roma1
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