The ATLAS detector has been designed for operation at the Large Hadron Collider at CERN. ATLAS includes electromagnetic and hadronic liquid argon calorimeters, with almost 200,000 channels of data ...that must be sampled at the LHC bunch crossing frequency of 40 MHz. The calorimeter electronics calibration and readout are performed by custom electronics developed specifically for these purposes. This paper describes the system performance of the ATLAS liquid argon calibration and readout electronics, including noise, energy and time resolution, and long term stability, with data taken mainly from full-system calibration runs performed after installation of the system in the ATLAS detector hall at CERN.
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
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.
Nucl.Instrum.Meth.A531:481-514,2004 A full azimuthal phi-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 < |eta| < 1.8. The
beam test set-up 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.
A full azimuthal phi-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 < |eta| < 1.8. The beam test set-up 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.
Ultrasonic pulse-echo non-destructive testing, combined with Distance Gain Size (DGS) analysis, is still the main method used for the inspection of forgings such as shafts or discs. This method ...allows the inspection to be carried out, assuring in turns the necessary sensitivity and defect detection capability in most of the cases. However, when testing large or highly attenuating samples with standard pulse-echo, the maximum achievable signal-to-noise ratio is limited by both the beam energy physical attenuation during the propagation and by the inherent divergence of any ultrasound beam emitted by a finite geometrical aperture. To face this issue, the application of the pulse-compression technique to the ultrasonic inspection of forgings was proposed by some of the present authors, in combination with the use of broadband ultrasonic transducers and broadband chirp excitation signals. Here, the method is extended by applying DGS analysis to the pulse-compression output signal. Both standard single-frequency/narrowband DGS and multi-frequency/broadband DGS analyses applied on pulse-compression data acquired on a forging with known defects are tested and compared. It is shown that the DGS analysis works properly with pulse-compression data collected by using a separate transmitter and receiver transducers. Narrowband analysis and broadband analyses provide almost identical results, but the latter exhibits advantages over the traditional method: it allows the inspection frequency to be optimized by using a single pair of transducers and with a single measurement. In addition, the range resolution achieved is higher than the one achievable for the narrowband case.
Fluid waves at the interface of Capacitive Micromachined Ultrasound Transducers (CMUTs) to the surrounding fluid are an often discussed and unwanted effect for medical applications, as they cause ...crosstalk between neighboring membranes. A new approach is presented which uses these dispersive surface waves for sensing fluid properties like density and viscosity. The paper describes the sensor principle, the FEM modeling and discusses first simulation results.
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