22 research outputs found
Measurement of pion and proton response and longitudinal shower profiles up to 20 nuclear interaction lengths with the ATLAS Tile calorimeter
The response of pions and protons in the energy range of 20 to 180 GeV produced at CERN's SPS H8 test beam line in the ATLAS iron-scintillator Tile hadron calorimeter has been measured. The test-beam configuration allowed to measure the longitudinal shower development for pions and protons up to 20 nuclear interaction lengths. It is found that pions penetrate deeper in the calorimeter than protons. However, protons induce showers that are wider laterally to the direction of the impinging particle. Including the measured total energy response, the pion to proton energy ratio and the resolution, all observations are consistent with a higher electromagnetic energy fraction in pion induced showers. The data are compared with GEANT4 simulations using several hadronic physics lists. The measured longitudinal shower profiles are described by an analytical shower parameterization within an accuracy of 5-10%. The amount of energy leaking out behind the calorimeter is determined and parameterised as a function of the beam energy and the calorimeter depth. This allows for a leakage correction of test-beam results in the standard projective geometry
A study of acculturation in psychotic and non-psychotic immigrants living in Athens
Background: Acculturation is the phenomenon that results when a group with one culture comes into continuous contact with a host culture. Aims: To investigate the correlation between acculturation and psychotic symptomatology in a group of immigrants suffering from psychosis and to explore differences in demographic factors related with the acculturation process between individuals with and without psychosis. Methods: Sixty-five patients and 317 non-psychotic immigrants were interviewed using the Immigrant Acculturation Scale (IAS) and a structured questionnaire for demographic data. The Positive and Negative Syndrome Scale (PANSS), the Calgary Depression Scale for Schizophrenia (CDSS) and the Gl?bal Assessment of Functioning (GAF) were also administered to all immigrants suffering from psychosis. Results: Total IAS scores, as well as IAS everyday life scores, were positively correlated with GAF scores. IAS everyday life score in the patient group related with religion, marital status, gender and years in Greece, while in the non-psychosis group it was related with gender and years in Greece. IAS wishful orientation/nostos (the strong desire for ones homeland) related with religion in both groups. The IAS identity in the psychosis group did not show any significant relation with any of the variables, while in the non-patient group, it was related with marital status, gender and years in Greece. Age, duration of residence in Greece and higher adoption of Greek ethnic identity were the variables that differentiated the two groups of immigrants. Conclusion: Acculturation in immigrants suffering from psychosis could be seen as a process that does not correlate strongly with the severity of the symptomatology but is probably influenced by different set of factors. © 2011 The Author(s)
Partially slotted crystals for a high-resolution gamma-camera based on a position sensitive photomultiplier
Partially slotted crystals have been designed and constructed and have
been used to evaluate the performance with respect to the spatial
resolution of a gamma-camera based on a position-sensitive
photomultiplier. It is shown that the resolution obtained with such a
crystal is only slightly worse than the one obtained with a fully
pixelized one whose cost, however, is much higher. (c) 2005 Elsevier
B.V. All rights reserved
Partially slotted crystals for a high-resolution g-camera based on a position sensitive photomultiplier
Abstract Partially slotted crystals have been designed and constructed and have been used to evaluate the performance with respect to the spatial resolution of a g-camera based on a position-sensitive photomultiplier. It is shown that the resolution obtained with such a crystal is only slightly worse than the one obtained with a fully pixelized one whose cost, however, is much higher.
The ATLAS hadronic tile calorimeter: from construction toward physics
The Tile Calorimeter, which constitutes the central section of the ATLAS hadronic calorimeter, is a non-compensating sampling device made of iron and scintillating tiles. The construction phase of the calorimeter is nearly complete, and most of the effort now is directed toward the final assembly and commissioning in the underground experimental hall. The layout of the calorimeter and the tasks carried out during construction are described, first with a brief reminder of the requirements that drove the calorimeter design. During the last few years a comprehensive test-beam program has been followed in order to establish the calorimeter electromagnetic energy scale, to study its uniformity, and to compare real data to Monte Carlo simulation. The test-beam setup and first results from the data are described. During the test-beam period in 2004, lasting several months, data have been acquired with a complete slice of the central ATLAS calorimeter. The data collected in the test-beam are crucial in order to study algorithms for hadronic energy reconstruction using single particles. The generalization of these algorithms to reconstruct jet energies will be the starting point for numerous physics studies in which jets play a leading role. The results obtained in applying these algorithms to simulated di-jet events are given in the last section of the note
The ATLAS hadronic tile calorimeter: from construction toward physics
ATLASThe Tile Calorimeter, which constitutes the central section of the ATLAS hadronic calorimeter, is a non-compensating sampling device made of iron and scintillating tiles. The construction phase of the calorimeter is nearly complete, and most of the effort now is directed toward the final assembly and commissioning in the underground experimental hall. The layout of the calorimeter and the tasks carried out during construction are described, first with a brief reminder of the requirements that drove the calorimeter design. During the last few years a comprehensive test-beam program has been followed in order to establish the calorimeter electromagnetic energy scale, to study its uniformity, and to compare real data to Monte Carlo simulation. The test-beam setup and first results from the data are described. During the test-beam period in 2004, lasting several months, data have been acquired with a complete slice of the central ATLAS calorimeter. The data collected in the test-beam are crucial in order to study algorithms for hadronic energy reconstruction using single particles. The generalization of these algorithms to reconstruct jet energies will be the starting point for numerous physics studies in which jets play a leading role. The results obtained in applying these algorithms to simulated di-jet events are given in the last section of the note
The ATLAS hadronic tile calorimeter: From construction toward-physics
The Tile Calorimeter, which constitutes the central section of the ATLAS hadronic calorimeter, is a non-compensating sampling device made of iron and scintillating tiles. The construction phase of the calorimeter is nearly complete, and most of the effort now is directed toward the final assembly and commissioning in the underground experimental hall. The layout of the calorimeter and the tasks carried out during construction are described, first with a brief reminder of the requirements that drove the calorimeter design. During the last few years a comprehensive test-beam program has been followed in order to establish the calorimeter electromagnetic energy scale, to study its uniformity, and to compare real data to Monte Carlo simulation. The test-beam setup and first results from the data are described. During the test-beam period in 2004, lasting several months, data have been acquired with a complete slice of the central ATLAS calorimeter. The data collected in the test-beam are crucial in order to study algorithms for hadronic energy reconstruction using single particles. The generalization of these algorithms to reconstruct jet energies will be the starting point for numerous physics studies in which jets play a leading role. The results obtained in applying these algorithms to simulated di-jet events are given in the last section of the note
A measurement of the photonuclear interactions of 180 GeV muons in iron: The tilecal system of the ATLAS collaboration
The energy spectrum and the cross section of photonuclear interactions of 180 GeV muons in iron were measured at the CERN SPS using prototype modules of the ATLAS hadron calorimeter. The differential cross section (NA/A)vdσ/dv for a muon fractional energy loss v = ΔEμ/Eμ was measured in the range 0.1<v<1. The integrated cross section (NA/A) ∫0.1 1 vdσ/dv is (0.26 ± 0.03stat ±.03stat) · 10-6 cm2g-1 in agreement with the theoretical prediction of 0.267 · 10-6 cm-2g-1. The best adjustment of the data to the theory is achieved for the value of σγN = (115 ± 18stat ± 15syst)μb of the photon-nucleon cross section for photons with energies in the range from 18 to 180 GeV