19 research outputs found
Hadron Energy Reconstruction for the ATLAS Calorimetry in the Framework of the Non-parametrical Method
This paper discusses hadron energy reconstruction for the ATLAS barrel
prototype combined calorimeter (consisting of a lead-liquid argon
electromagnetic part and an iron-scintillator hadronic part) in the framework
of the non-parametrical method. The non-parametrical method utilizes only the
known ratios and the electron calibration constants and does not require
the determination of any parameters by a minimization technique. Thus, this
technique lends itself to an easy use in a first level trigger. The
reconstructed mean values of the hadron energies are within of the
true values and the fractional energy resolution is . The value of the ratio
obtained for the electromagnetic compartment of the combined calorimeter is
and agrees with the prediction that for this
electromagnetic calorimeter. Results of a study of the longitudinal hadronic
shower development are also presented. The data have been taken in the H8 beam
line of the CERN SPS using pions of energies from 10 to 300 GeV.Comment: 33 pages, 13 figures, Will be published in NIM
Performance of an endcap prototype of the Atlas accordion electromagnetic calorimeter
The design and construction of a lead-liquid argon endcap calorimeter prototype using an accordion geometry and conceived as a sector of the inner wheel of the endcap calorimeter of the future ATLAS experiment at the LHC is described. The performance obtained using electron beam data is presented. The main results are an energy resolution with a sampling term below and a small local constant term, a good linearity of the response with the incident energy and a global constant term of 0.8\% over an extended area in the rapidity range of . These properties make the design suitable for the ATLAS electromagnetic endcap calorimeter
Test beam results of a stereo preshower integrated in the liquid argon accordion calorimeter
This paper describes the construction of an integrated preshower within the RD3 liquid argon accordion calorimeter. It has a stereo view which enables the measurement of two transverse coordinates. The prototype was tested at CERN with electrons, photons and muons to validate its capability to work at LHC (Energy resolution, impact point resolution, angular resolution, π o γ rejection). (Elsevier
The CPLEAR detector at CERN
The CPLEAR collaboration has constructed a detector at CERN for an extensive programme of CP-, T- and CPT-symmetry studies using and produced by the annihilation of 's in a hydrogen gas target. The and are identified by their companion products of the annihilation which are tracked with multiwire proportional chambers, drift chambers and streamer tubes. Particle identification is carried out with a liquid Cherenkov detector for fast separation of pions and kaons and with scintillators which allow the measurement of time of flight and energy loss. Photons are measured with a lead/gas sampling electromagnetic calorimeter. The required antiproton annihilation modes are selected by fast online processors using the tracking chamber and particle identification information. All the detectors are mounted in a 0.44 T uniform field of an axial solenoid of diameter 2 m and length 3.6 m to form a magnetic spectrometer capable of full on-line reconstruction and selection of events. The design, operating parameters and performance of the sub-detectors are described.
Dispositif de détection de la désintégration de radioisotopes dans un tissu biologique
Internationale: A61B5/00 ; G01T1/24 ; A6B5/00 ; G01T1/0
XPAD3 hybrid pixel detector applications
Using Si sensors, the XPAD3 chip can be used from 4 up to 25 keV. The CdTe detector was designed to improve efficiency at higher energies (60 keV), but it still works at low energy: data were collected at 8 keV. Firstly, small detector prototypes were built and used for scattering experiments at BM02/ESRF and DIFABS/SOLEIL. Comparisons were made by collecting small angle X-ray scattering data using the same settings with the XPAD3 and the beam line CCD camera, as well as diffuse scattering from a quasi-crystal. Finally, a surface diffraction experiment was performed to characterize the strain in a few layers of GaInAs epitaxially grown on a GaAs single crystal
Adaptation to Abundant Low Quality Food Improves the Ability to Compete for Limited Rich Food in Drosophila melanogaster.
The rate of food consumption is a major factor affecting success in scramble competition for a limited amount of easy-to-find food. Accordingly, several studies report positive genetic correlations between larval competitive ability and feeding rate in Drosophila; both become enhanced in populations evolving under larval crowding. Here, we report the experimental evolution of enhanced competitive ability in populations of D. melanogaster previously maintained for 84 generations at low density on an extremely poor larval food. In contrast to previous studies, greater competitive ability was not associated with the evolution of higher feeding rate; if anything, the correlation between the two traits across lines tended to be negative. Thus, enhanced competitive ability may be favored by nutritional stress even when competition is not intense, and competitive ability may be decoupled from the rate of food consumption