NIM paper for EMCal test beam
measurements
contents:
• Introduction
• Calorimeter model design and readout
• Test beam measurements
- LED calibration system
- Signal reconstruction
- Light Yield
- Energy resolution
- Linearity and uniformity of energy response
- Position resolution
- Response to hadrons
• Cosmic ray calibration
• Summary
NIM paper for EMCal test beam
measurements
LED calibration system
• monitoring and calibration
successfully tested
• data base and interface
developed
NIM paper for EMCal test beam
measurements
light yield
final statistics:
<light yield> = 4.3 ± 1.4 p.e./MeV
just as for PHOS
photoelectrons / MeV (for APD gain M=1)
NIM paper for EMCal test beam
measurements
energy resolution
simulation:
1.6
8.0
7.4
•
const. term: stable high quality
detector fabrication & good tower-bytower calibration
•
stocastic term: light attenuation not
simulated  needs to be implemented
too strong segmentation ? :
resolution:
high sampling  light collection
fraction
inefficiencies
•
linear term: electronics noise less in
reality 
NIM paper for EMCal test beam
measurements
energy resolution
simulation:
1.6
8.0
7.4
 to be included in simulation:
 light attenuation
 light collection efficiency: depth (equiv. E) dependent !
…instead of const. factor
NIM paper for EMCal test beam
measurements
energy resolution
• shorter shaping time (100nsEMCal)
yield similar results than long one
(1usPHOS)
• uniformity of response within 1%
• no differences for tower centers or edges;
between tower and module centers
• no differences for tilted configurations
• good linearity 10-100 GeV:
- cubic fct for E<20GeV
(threshold effects)
- quadratic fct for 20-100GeV
(longitudinal shower leakage)
NIM paper for EMCal test beam
measurements
position resolution
FNAL result:
• Irakli working on CERN data:
- MWPC resolution ~3mm
- only 2 or 3 working planes
…to be concluded ~1 week
 setup much worse than for FNAL
1.5 mm + 5.3 mm / E
(5 working planes of ~1mm resol.)
[ comment David]
 possibly stay with FNAL result
NIM paper for EMCal test beam
measurements
response to hadrons
test beam data
counts
simulation
40 GeV hadrons
Energy [GeV]
NIM paper for EMCal test beam
measurements
cosmic ray calibration
precalibration using
cosmic muons prior to
installation:
384 towers
rel. spread ~5%
NIM paper for EMCAL test beam
measurements
open points
position resolution from CERN test beam [Irakli working on it]
 possibly stay with FNAL result ?
response to hadrons and e/h separation [?]
improvement of EMCal MC simulations based on tb results:
 simulate light attenuation and light collection efficiency
 Please send your comments to the current draft !
 native speaker for language corrections wanted
 EMCal group official authorlist (from TDR ?)