Note: Work in Progress !!
Introduction
Principle of a dual read out calorimeter
The response of a calorimeter is very different for e+, e- and photons compared to hadrons. For e+, e- and photons the total energy of the incoming particle is converted into detectable kinetic energy of electrons leading to excellent energy resolution for electrons/photons. Hadrons on the other hand break nuclei and liberate nucleons/nuclear fragments. Even if the kinetic energy of the resulting nucleons is measured, the significant fraction of energy is lost to overcome the binding energy. Fluctuations of the number of broken nuclei dominate fluctuations of the observed energy leading to a relatively poor energy resolution for hadrons.This is demonstrated in the figure below where the ionization loss of a 10 GeV Pion is compared with the ionization loss of a 10 GeV electron. In both cases we use a simple Iron block as an absorber that contains the entire shower.
Large number of broken nuclei:
- Large number of slow neutrons
- Small fraction of energy in a form of neutral pions.
Very few broken nuclei:
- Small number of slow neutrons
- Large fraction of energy in a form of neutral pions.
Eem/Etot ~ ECherenkov/Eionization
'EM' shower => Relativistic electrons => Lots of Cherenkov light
Hadronic shower => Most particles below the Cherenkov threshold
Use this fact to correct hadron response
Novel calorimeter concepts under consideration for future lepton collider experiments are aimed to achieve high energy resolution for single hadrons and for hadronic jets. The energy resolution improvement is achieved by reading out two different signal components: Szintilation light which is proportional to the energy deposited via ionization and Cerenkov light which is used as an estimator of the energy loss due to nuclear processes. The cerenkov signal can be used to correct the energy deposit as measured by the szintilation signal.
Reconstruction of jet-jet invariant mass in a segmented total absorption dual read out calorimeter is investigated in a specific example of the crystal-based calorimeter for the SiD detector. The detector geometry is defined and the detector simulation is carried out within the geant 4 based SLIC (Simulation for LInear Collider) framework.
The analysis programs are developed in JAVA within the JAS3 (Java Analys Studio)
environment.
Correlation between the total observed ionization energy and the electromagnetic component of the shower, as measured by the Cherenkov component. The calibration factor K is determined by the requirement that K×ECherenkov = Eionization for electrons.
The CCAL02 detector
Is an implementation of a daul read-out, total absorption crystal calorimeter made of BGO crystals. CCAL02 is based on the SID02 geometry but the space currently occupied by ECAL/HCAL Barrel/Endcap is replaced by the Crystal calorimeter. All other detectors (tracking etc.) as they are. ECAL deep enough to contain most EM showers.
Material |
Density |
Radiation length |
Interaction length |
||
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[g/cm3] |
[cm] |
[cm] |
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BGO |
7.13 |
1.12 |
21.88 |
||
PbWO4 |
8.3 |
0.9 |
18. |
||
SCG1-C |
3.36 |
4.25 |
45.6 |
|
|
|
|
BGO |
|
PbWO4 |
|
||
---|---|---|---|---|---|---|---|---|---|
Detector |
Layers |
Thickness/layer |
Segmentation |
X0 |
Lambda |
X0 |
Lambda |
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|
|
[cm] |
[cmxcm] |
|
|
|
|
]]></ac:plain-text-body></ac:structured-macro> |
ECAL Barrel |
8 |
3 |
3x3 |
21.4 |
1.1 |
27 |
1.3 |
||
HCAL Barrel |
17 |
6 |
6x6 |
|
4.7 |
|
5.7 |
||
Total Barrel |
25 |
|
|
|
5.8 |
|
7 |
||
|
|
|
|
|
|
|
|
||
ECAL EndCAP |
8 |
3 |
3x3 |
21.4 |
1.1 |
27 |
1.3 |
||
HCAL EndCAP |
17 |
6 |
6x6 |
|
4.7 |
|
5.7 |
||
Total EndCAP |
25 |
|
|
|
5.8 |
|
7 |
The Table below list all the data samples currently available at Fermilab. The files can be found on the following directory (on the bluearc system)
/ilc/ild/wenzel/ccal02/slcio_combined
File Name |
Type of Events |
Nr of Events |
---|---|---|
pi_Theta90_1GeV.slcio |
single 1 GeV pions at theta 90 degrees |
20000 |
pi_Theta90_2GeV.slcio |
single 2 GeV pions at theta 90 degrees |
20000 |
pi_Theta90_5GeV.slcio |
single 5 GeV pions at theta 90 degrees |
20000 |
pi_Theta90_10GeV.slcio |
single 10 GeV pions at theta 90 degrees |
20000 |
pi_Theta90_20GeV.slcio |
single 20 GeV pions at theta 90 degrees |
20000 |
pi_Theta90_50GeV.slcio |
single 50 GeV pions at theta 90 degrees |
20000 |
pi_Theta90_100GeV.slcio |
single 100 GeV pions at theta 90 degrees |
20000 |
electron_Theta90_1GeV.slcio |
single 1 GeV electrons at theta 90 degrees |
5000 |
electron_Theta90_2GeV.slcio |
single 2 GeV electrons at theta 90 degrees |
5000 |
electron_Theta90_5GeV.slcio |
single 5 GeV electrons at theta 90 degrees |
5000 |
electron_Theta90_10GeV.slcio |
single 10 GeV electrons at theta 90 degrees |
5000 |
electron_Theta90_20GeV.slcio |
single 20 GeV electrons at theta 90 degrees |
5000 |
electron_Theta90_50GeV.slcio |
single 50 GeV electrons at theta 90 degrees |
2432 |
electron_Theta90_100GeV.slcio |
single 100 GeV electrons at theta 90 degrees |
1215 |
neutrons_20GeV.slcio |
single 20 GeV neutrons |
200 |
muon_Theta90_50GeV.slcio |
single 50 GeV muons |
5000 |
K0L_Theta90_1GeV.slcio |
single 1 GeV K longs at theta 90 degrees |
20000 |
K0L_Theta90_2GeV.slcio |
single 2 GeV K longs at theta 90 degrees |
20000 |
K0L_Theta90_5GeV.slcio |
single 5 GeV K longs at theta 90 degrees |
|
K0L_Theta90_10GeV.slcio |
single 10 GeV K longs at theta 90 degrees |
|
K0L_Theta90_20GeV.slcio |
single 20 GeV K longs at theta 90 degrees |
|
K0L_Theta90_50GeV.slcio |
single 50 GeV K longs at theta 90 degrees |
|
K0L_Theta90_100GeV.slcio |
single 100 GeV K longs at theta 90 degrees |
|
|
|
|
panpyZZnunubaruds-0-1000.slcio |
ZZ -> neutrino neutrino jet jet |
1000 |
Z0_Theta90_50GeV.slcio |
single 50 GeV Z 's at theta 90 degrees |
|
W_0_100.slcio |
single 0-100 GeV W 's |
20000 |
W_100_200.slcio |
single 100-200 GeV W 's |
20000 |
pythiaZhiggs120_uds_4jets.slcio |
associated Z Higgs production Z and Higgs decay into light quarks (jets) |
|
The Table below list all the data samples currently available at Fermilab. The files can be found on the following directory (on the bluearc system)
/ilc/ild/wenzel/ccal02/slcio_combined