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

Results from a combined test of an electromagnetic liquid argon calorimeter with a hadronic scintillating-tile calorimeter

The first combined test of an electromagnetic liquid argon accordion calorimeter and a hadronic scintillating-tile calorimeter was carried out at the CERN SPS, These devices are prototypes of the barrel calorimeter of the future ATLAS experiment at the LHC. The energy resolution of pions in the energy range from 20 to 300 GeV at an incident angle a of about 11 degrees is well-described by the expression sigma/E = ((46.5 +/- 6.0)%/root E + (1.2 +/- 0.3)%) + (3.2 +/- 0.4) GeV/E. Shower profiles, shower leakage, and the angular resolution of hadronic showers were also studied

Results from a combined test of an electromagnetic liquid argon calorimeter with a hadronic scintillating-tile calorimeter

The first combined test of an electromagnetic liquid argon accordion calorimeter and a hadronic scintillating-tile calorimeter was carried out at the CERN SPS. These devices are prototypes of the barrel calorimeter of the future ATLAS experiment at the LHC. The energy resolution of pions in the energy range from 20 to 300 GeV at an incident angle θ of about 11c is well-described by the expression σ/E = ((46.5 ± 6.0)%/√E + (1.2 ± 0.3)%) ⊗ (3.2 ± 0.4)GeV/E. Shower profiles, shower leakage, and the angular resolution of hadronic showers were also studied

Results from a combined test of an electromagnetic liquid argon calorimeter with a hadronic scintillating-tile calorimeter

The first combined test of an electromagnetic liquid argon accordion calorimeter and a hadronic scintillating-tile calorimeter was carried out at the CERN SPS. These devices are prototypes of the barrel calorimeter of the future ATLAS experiment at the LHC. The energy resolution of pions in the energy range from 20 to 300 GeV at an incident angle θ of about 11c is well-described by the expression σ/E = ((46.5 ± 6.0)%/√E + (1.2 ± 0.3)%) ⊗ (3.2 ± 0.4)GeV/E. Shower profiles, shower leakage, and the angular resolution of hadronic showers were also studied

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 e/h 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 +/-1% of the true values and the fractional energy resolution is [(58+/-3)%/rootE+(2.5+/-0.3)%]circle plus(1.7+/-0.2)/E. The value of the e/h ratio obtained for the electromagnetic compartment of the combined calorimeter is 1.74+/-0.04 and agrees with the prediction that e/h > 1.66 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. (C) 2002 Elsevier Science B.V. All rights reserved

Performance of the ATLAS Detector using First Collision Data

More than half a million minimum-bias events of LHC collision data were collected by the ATLAS experiment in December 2009 at centre-of-mass energies of 0.9 TeV and 2.36 TeV. This paper reports on studies of the initial performance of the ATLAS detector from these data. Comparisons between data and Monte Carlo predictions are shown for distributions of several track- and calorimeter-based quantities. The good performance of the ATLAS detector in these first data gives confidence for successful running at higher energies