5HTXLHVFDQWL Q3 DFH · 2 ; < 0 0 0 ) j < p ( 0 ( 0 ) ( ( < p 2 0
Calibration with p 0
description
Transcript of Calibration with p 0
M.N Minard Calorimeter meeting 5-2-09
Calibration with 0
Work from Vanya
Gaël Rospabé Phd
M.N Minard Calorimeter meeting 5-2-09
Cluster selection
• Select 0 reconstructed from 2 separate Ecal clusters :
– Energy range of : up to 5-8 GeV– No charge track within the Ecal cluster– Pt g >300Mev/c
• On minimum biais events signal with low background :– Associate electromagnetic cluster within 80 cm – PS >10MeV
• Select pairs within :– Average mass +- 2
http://lappwiki01.in2p3.fr/LHCB-LAPP/index.php/Ecal_Calibration#Calibration_algorithm
100kevts, MinBias, 900GeV
900GeV
M.N Minard Calorimeter meeting 5-2-09
Calibration
• Estimate the miscalibration– Select cell: Ecell >60% Ecluster
– Fill correction factor histogram:• C = Mrec/mpi0• N>200 evt • Calculate average
– On the same events iterate .
To estimate :-Number of events / histogram -Number of iteration
M.N Minard Calorimeter meeting 5-2-09
Does it work in all the cases?
• No tracking 900GeV– All clusters are combined– Higher background– Select low multiplicity events
• #Clusters <20
– 14 TeV with tracking
900 GeV
No tracking
70/100evts
S/B=5.2
14TeV
S/B = 3 0.80/100evts
14TeVNo tracking
M.N Minard Calorimeter meeting 5-2-09
Fisher for -id
Profils transverses : Seed, S4Ecal et ECl
Profils longitudinaux : PS et Hcal Impacts dans le SPD
Signal
Fond
M.N Minard Calorimeter meeting 5-2-09
14 TeV no tracking
Configuration N evts Temps
14TeVtrajectographe
5,4.108 75h
14TeV sansTrajectographe
1,8.109 250h
# 0 per cell depend upon the initial calibration dispersion
Data taking at 2kHz
After Fisher selection :
HLT independent 1% intercalibration reached
14 TeV - tracking
30 /100evtsS/B = 3
Worth waiting for tracking
M.N Minard Calorimeter meeting 5-2-09
Tools available
• Fisher tool : place or improvement ..– In absence of tracking , HCAL info reduce the combinatorial
• Recalibration tools : – Selection – Correction average – Iteration – Stop procedure to improve.
• http://lappwiki01.in2p3.fr/LHCB-LAPP/index.php/Ecal_Calibration#Calibration_algorithm
• Gaël can be joined ( Annecy )