Abstract
The CALICE Semi-Digital Hadron Calorimeter technological
prototype completed in 2011 is a sampling calorimeter using Glass
Resistive Plate Chamber (GRPC) detectors as the active medium. This
...technology is one of the two options proposed for the hadron
calorimeter of the International Large Detector for the
International Linear Collider. The prototype was exposed in 2015 to
beams of muons, electrons, and pions of different energies at the
CERN Super Proton Synchrotron. The use of this technology for
future experiments requires a reliable simulation of its response
that can predict its performance. GEANT4 combined with a
digitization algorithm was used to simulate the prototype. It
describes the full path of the signal: showering, gas avalanches,
charge induction, and hit triggering. The simulation was tuned using
muon tracks and electromagnetic showers for accounting for detector
inhomogeneity and tested on hadronic showers collected in the test
beam. This publication describes developments of the digitization
algorithm. It is used to predict the stability of the detector
performance against various changes in the data-taking conditions,
including temperature, pressure, magnetic field, GRPC width
variations, and gas mixture variations. These predictions are
confronted with test beam data and provide an attempt to explain the
detector properties. The data-taking conditions such as temperature
and potential detector inhomogeneities affect energy density
measurements but have small impact on detector efficiency.
We present a study of the response of the highly granular Digital Hadronic Calorimeter with steel absorbers, the Fe-DHCAL, to positrons, muons, and pions with momenta ranging from 2 to 60GeV/c. ...Developed in the context of the CALICE collaboration, this hadron calorimeter utilises Resistive Plate Chambers as active media, interspersed with steel absorber plates. With a transverse granularity of 1×1cm2 and a longitudinal segmentation of 38 layers, the calorimeter counted 350,208 readout channels, each read out with single-bit resolution (digital readout). The data were recorded in the Fermilab test beam in 2010–11. The analysis includes measurements of the calorimeter response and the energy resolution to positrons and muons, as well as detailed studies of various shower shape quantities. The results are compared to simulations based on Geant4, which utilise different electromagnetic and hadronic physics lists.
Abstract
The CALICE collaboration is developing highly granular
electromagnetic and hadronic calorimeters for detectors at future
energy frontier electron-positron colliders. After successful tests
...of a physics prototype, a technological prototype of the Analog
Hadron Calorimeter has been built, based on a design and
construction techniques scalable to a collider detector. The
prototype consists of a steel absorber structure and active layers
of small scintillator tiles that are individually read out by
directly coupled SiPMs. Each layer has an active area of
72 × 72 cm^2 and a tile size of
3 × 3 cm^2. With 38 active layers, the prototype
has nearly 22,000 readout channels, and its total thickness
amounts to 4.4 nuclear interaction lengths. The dedicated readout
electronics provide time stamping of each hit with an expected
resolution of about 1 ns. The prototype was constructed in
2017 and commissioned in beam tests at DESY. It recorded muons,
hadron showers and electron showers at different energies in test
beams at CERN in 2018. In this paper, the design of the prototype,
its construction and commissioning are described. The methods used
to calibrate the detector are detailed, and the performance achieved
in terms of uniformity and stability is presented.
A detailed investigation of hadronic interactions is performed using π−-mesons with energies in the range 2–10 GeV incident on a high granularity silicon–tungsten electromagnetic calorimeter. The ...data were recorded at FNAL in 2008. The region in which the π−-mesons interact with the detector material and the produced secondary particles are characterised using a novel track-finding algorithm that reconstructs tracks within hadronic showers in a calorimeter in the absence of a magnetic field. The principle of carrying out detector monitoring and calibration using secondary tracks is also demonstrated.
Abstract A neural network for software compensation was developed for the highly granular CALICE Analogue Hadronic Calorimeter (AHCAL). The neural network uses spatial and temporal event information ...from the AHCAL and energy information, which is expected to improve sensitivity to shower development and the neutron fraction of the hadron shower. The neural network method produced a depth-dependent energy weighting and a time-dependent threshold for enhancing energy deposits consistent with the timescale of evaporation neutrons. Additionally, it was observed to learn an energy-weighting indicative of longitudinal leakage correction. In addition, the method produced a linear detector response and outperformed a published control method regarding resolution for every particle energy studied.
Abstract
The CALICE Semi-Digital Hadronic CALorimeter (SDHCAL) is the
first technological prototype in a family of high-granularity
calorimeters developed by the CALICE Collaboration to equip the
...experiments of future lepton colliders. The SDHCAL is a sampling
calorimeter using stainless steel for absorber and Glass Resistive
Plate Chambers (GRPC) as a sensitive medium. The GRPC are read out
by 1 cm× 1 cm pickup pads combined to a
multi-electronics. The prototype was exposed to hadron beams in
both the CERN PS and the SPS beamlines in 2015 allowing the test of
the SDHCAL in a large energy range from 3 GeV to 80 GeV. After
introducing the method used to select the hadrons of our data and
reject the muon and electron contamination, we present the energy
reconstruction approach that we apply to the data collected from
both beamlines and we discuss the response linearity and the energy
resolution of the SDHCAL. The results obtained in the two beamlines
confirm the excellent SDHCAL performance observed with the data
collected with the same prototype in the SPS beamline in 2012. They
also show the stability of the SDHCAL in different beam conditions
and different time periods.
This paper presents results obtained with the combined CALICE Scintillator Electromagnetic Calorimeter, Analogue Hadronic Calorimeter and Tail Catcher & Muon Tracker, three high granularity ...scintillator-silicon photomultiplier calorimeter prototypes. The response of the system to pions with momenta between 4 GeV/c and 32 GeV/c is analysed, including the average energy response, resolution, and longitudinal shower profiles. Two techniques are applied to reconstruct the initial particle energy from the measured energy depositions; a standard energy reconstruction which is linear in the measured depositions and a software compensation technique based on reweighting individually measured depositions according to their hit energy. The results are compared to predictions of the GEANT 4 physics lists QGSP_BERT_HP and FTFP_BERT_HP.
The CALICE Semi-Digital Hadronic CALorimeter (SDHCAL) prototype using Glass Resistive Plate Chambers as a sensitive medium is the first technological prototype of a family of high-granularity ...calorimeters developed by the CALICE collaboration to equip the experiments of future leptonic colliders. It was exposed to beams of hadrons, electrons and muons several times in the CERN PS and SPS beamlines between 2012 and 2018. We present here a new method of particle identification within the SDHCAL using the Boosted Decision Trees (BDT) method applied to the data collected in 2015. The performance of the method is tested first with Geant4-based simulated events and then on the data collected by the SDHCAL in the energy range between 10 and 80 GeV with 10 GeV energy steps. The BDT method is then used to reject the electrons and muons that contaminate the SPS hadron beams. The rejection power of the new method is estimated to be as high as 99.0% for the muons and 99.4% for the electrons associated to a pion selection efficiency of about 95.0%.
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