The construction and the assembly of the two end-caps of the ATLAS liquid argon electromagnetic calorimeter as well as their test and qualification programs are described. The work described here ...started at the beginning of 2001 and lasted for approximately three years. The results of the qualification tests performed before installation in the LHC ATLAS pit are given. The detectors are now installed in the ATLAS cavern, full of liquid argon and being commissioned. The complete detectors coverage is powered with high voltage and readout.
The local hadronic calibration scheme developed for the reconstruction and calibration of jets and missing transverse energy in ATLAS has been evaluated using data obtained during combined beam tests ...of modules of the ATLAS liquid argon endcap and forward calorimeters. These tests covered the pseudorapidity range of 2.5<|η|<4.0. The analysis has been performed using special sets of calibration weights and corrections obtained with the Geant4 simulation of a detailed beam-test setup. The evaluation itself has been performed through the careful study of specific calorimeter performance parameters such as e.g. energy response and resolution, shower shapes, as well as different physics lists of the Geant4 simulation.
The local hadronic calibration scheme developed for the reconstruction and calibration of jets and missing transverse energy in ATLAS has been evaluated using data obtained during combined beam tests ...of modules of the ATLAS liquid argon endcap and forward calorimeters. These tests covered the pseudorapidity range of 2.5 < | ? | < 4.0 . The analysis has been performed using special sets of calibration weights and corrections obtained with the Geant4 simulation of a detailed beam-test setup. The evaluation itself has been performed through the careful study of specific calorimeter performance parameters such as e.g. energy response and resolution, shower shapes, as well as different physics lists of the Geant4 simulation.
A full azimuthal
φ
-wedge of the ATLAS liquid argon end-cap calorimeter has been exposed to beams of electrons, muons and pions in the energy range
6
GeV
⩽
E
⩽
200
GeV
at the CERN SPS. The angular ...region studied corresponds to the ATLAS impact position around the pseudorapidity interval
1.6
<
|
η
|
<
1.8
. The beam test setup is described. A detailed study of the performance is given as well as the related intercalibration constants obtained. Following the ATLAS hadronic calibration proposal, a first study of the hadron calibration using a weighting ansatz is presented. The results are compared to predictions from Monte Carlo simulations, based on GEANT 3 and GEANT 4 models.
The pseudorapidity region
2.5
<
|
η
|
<
4.0
in ATLAS is a particularly complex transition zone between the endcap and forward calorimeters. A set-up consisting of
1
4
resp.
1
8
of the full azimuthal ...acceptance of the ATLAS liquid argon endcap and forward calorimeters has been exposed to beams of electrons, pions and muons in the energy range
E
⩽
200
GeV
at the CERN SPS. Data have been taken in the endcap and forward calorimeter regions as well as in the transition region. This beam test set-up corresponds very closely to the geometry and support structures in ATLAS. A detailed study of the performance in the endcap and forward calorimeter regions is described. The data are compared with MC simulations based on GEANT 4 models.
Performance of the ATLAS hadronic end-cap calorimeter in beam tests Dowler, B; Pinfold, J; Soukup, J ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
04/2002, Letnik:
482, Številka:
1-2
Journal Article
Recenzirano
Odprti dostop
Modules of the ATLAS liquid argon Hadronic End-cap Calorimeter (HEC) were exposed to beams of electrons, muons and pions in the energy range 6⩽E⩽200GeV at the CERN SPS. A description of the HEC and ...of the beam test setup are given. Results on the energy response and resolution are presented and compared with simulations. The ATLAS energy resolution for jets in the end-cap region is inferred and meets the ATLAS requirements.
A precision liquid hydrogen bubble chamber with rapid cycling capability and a photographed volume of 150 × 70 × 50 mm
3 has been constructed to study short-living elementary particles. Its ...refrigeration system is operated with liquid helium. The chamber body, manufactured from the polycarbonate Lexan
®, is almost free of vibrations due to the innovative expansion system with two pistons operating in opposite directions. The chamber operates with 5 ms cycle time and a rate up to 30 s
−1. The chamber has already been cycled 6.7 million times and about 0.3 million pictures have been taken. At the hydrogen temperature of 29.8 K a track density of 150 bubbles/cm has been achieved with bubble diameters of 25 μm.