Introduction

This page collects information about a total absorption dual readout calorimeter as implemented in SLIC. You will find information about the detector parameters, how to run the simulation, where data sets and programs to analyze the data can be found.  The dual read out/ optical processes group meets every Tuesday at 10 am in the Quarium wh 8th floor. It is possible to dial in by phone or follow the meeting via skype. The agenda page can be found on the following web page:
http://ilcagenda.linearcollider.org/categoryDisplay.py?categId=151

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.
The following table lists the properties of some crystal materials.

The following table lists the parameters of the ccal02 calorimeter:

How to run the simulation

The shell script below demonstrates how to run slic using the ccal02 geometry. Note for a dual readout calorimeter it is important that the
/physics/enableOptical flag is set otherwise no Cherenkov photons will be created!

#!/bin/tcsh -f
echo start
/bin/date
set current = 0
@ current = $1
echo $current
cat > optical_K0L_10GeV.mac << +EOF
/physics/enableOptical
/generator/filename /ilc/ild/wenzel/ccal02/stdhep/K0L_Theta90_10GeV-${current}-5000.stdhep
/lcio/path /ilc/ild/wenzel/ccal02/slcio
/lcio/filename K0L_Theta90_10GeV-${current}-5000
/lcio/fileExists delete
/lcdd/url /ilc/ild/wenzel/ccal02/ccal02/ccal02.lcdd
/run/initialize
/run/beamOn 5000
+EOF

echo optical_K0L_10GeV.mac
echo start
/bin/date
/grid/app/CherSimDist_may2009/SimDist/scripts/slic.sh -m  optical_K0L_10GeV.mac
/bin/date
echo done

A example how to run this on fermigrid is the following:

universe = grid
type = gt2
globusscheduler = fngp-osg.fnal.gov/jobmanager-condor
executable = ./slic_grid_K0L_10GeV.csh
transfer_output = true
transfer_error = true
transfer_executable = true
environment = "ClusterProcess=$(Cluster)-$(Process)"
log = slic_grid.log.$(Cluster).$(Process)
notification = NEVER
output = slic_grid.out.$(Cluster).$(Process)
error = slic_grid.err.$(Cluster).$(Process)
stream_output = false
stream_error = false
ShouldTransferFiles = YES
WhenToTransferOutput = ON_EXIT
globusrsl = (jobtype=single)(maxwalltime=999)
Arguments = $(Process)
queue 4

For more information about running jobs on the grid look at the following web page: http://confluence.slac.stanford.edu/display/ilc/How do I use the OSG Grid

Available Data sets

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