264 research outputs found
Test beam studies of the light yield, time and coordinate resolutions of scintillator strips with WLS fibers and SiPM readout
Prototype scintilator+WLS strips with SiPM readout for large muon detection
systems were tested in the muon beam of the Fermilab Test Beam Facility. Light
yield of up to 137 photoelectrons per muon per strip has been observed, as well
as time resolution of 330 ps and position resolution along the strip of 5.4 cm.Comment: 7 pages, 11 figures, version accepted for publication in NIM
Ultra-Fast Hadronic Calorimetry
Calorimeters for particle physics experiments with integration time of a few
ns will substantially improve the capability of the experiment to resolve event
pileup and to reject backgrounds. In this paper the time development of
hadronic showers induced by 30 and 60 GeV positive pions and 120 GeV protons is
studied using Monte Carlo simulation and beam tests with a prototype of a
sampling steel-scintillator hadronic calorimeter. In the beam tests,
scintillator signals induced by hadronic showers in steel are sampled with a
period of 0.2 ns and precisely time-aligned in order to study the average
signal waveform at various locations with respect to the beam particle impact.
Simulations of the same setup are performed using the MARS15 code. Both
simulation and test beam results suggest that energy deposition in steel
calorimeters develop over a time shorter than 2 ns providing opportunity for
ultra-fast calorimetry. Simulation results for an "ideal" calorimeter
consisting exclusively of bulk tungsten or copper are presented to establish
the lower limit of the signal integration window.Comment: 10 pages, 16 figures, accepted for publication in NIM
Time and position resolution of the scintillator strips for a muon system at future colliders
Prototype scintilator + WLS strips with SiPM readout for a muon system at future colliders were tested for light yield, time resolution and position resolution. Depending on the configuration, light yield of up to 36 photoelectrons per muon per SiPM has been observed, as well as time resolution of 0.45 ns and position resolution along the strip of 7.7 cm. (C) 2016 Elsevier B.V. All rights reserved
Universal Slip Dynamics in Metallic Glasses and Granular Matter ā Linking Frictional Weakening with Inertial Effects
Slowly strained solids deform via intermittent slips that exhibit a material-independent critical size distribution. Here, by comparing two disparate systems - granular materials and bulk metallic glasses - we show evidence that not only the statistics of slips but also their dynamics are remarkably similar, i.e. independent of the microscopic details of the material. By resolving and comparing the full time evolution of avalanches in bulk metallic glasses and granular materials, we uncover a regime of universal deformation dynamics. We experimentally verify the predicted universal scaling functions for the dynamics of individual avalanches in both systems, and show that both the slip statistics and dynamics are independent of the scale and details of the material structure and interactions, thus settling a long-standing debate as to whether or not the claim of universality includes only the slip statistics or also the slip dynamics. The results imply that the frictional weakening in granular materials and the interplay of damping, weakening and inertial effects in bulk metallic glasses have strikingly similar effects on the slip dynamics. These results are important for transferring experimental results across scales and material structures in a single theory of deformation dynamics
Status Report of the DPHEP Study Group: Towards a Global Effort for Sustainable Data Preservation in High Energy Physics
Data from high-energy physics (HEP) experiments are collected with
significant financial and human effort and are mostly unique. An
inter-experimental study group on HEP data preservation and long-term analysis
was convened as a panel of the International Committee for Future Accelerators
(ICFA). The group was formed by large collider-based experiments and
investigated the technical and organisational aspects of HEP data preservation.
An intermediate report was released in November 2009 addressing the general
issues of data preservation in HEP. This paper includes and extends the
intermediate report. It provides an analysis of the research case for data
preservation and a detailed description of the various projects at experiment,
laboratory and international levels. In addition, the paper provides a concrete
proposal for an international organisation in charge of the data management and
policies in high-energy physics
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