6,104 research outputs found
A Volume Clearing Algorithm for Muon Tomography
The primary objective is to enhance muon-tomographic image reconstruction
capability by providing distinctive information in terms of deciding on the
properties of regions or voxels within a probed volume "V" during any point of
scanning: threat type, non-threat type, or not-sufficient data. An algorithm
(MTclear) is being developed to ray-trace muon tracks and count how many
straight tracks are passing through a voxel. If a voxel "v" has sufficient
number of straight tracks (t), then "v" is a non-threat type voxel, unless
there are sufficient number of scattering points (p) in "v" that will make it a
threat-type voxel. The algorithm also keeps track of voxels for which not
enough information is known: where p and v both fall below their respective
threshold parameters. We present preliminary results showing how the algorithm
works on data collected with a Muon Tomography station based on gas electron
multipliers operated by our group. The MTclear algorithm provides more
comprehensive information to a human operator or to a decision algorithm than
that provided by conventional muon-tomographic reconstruction algorithms, in
terms of qualitatively determining the threat possibility from a probed volume.
This is quite important because only low numbers of cosmic ray source muons are
typically available in nature for tomography, while a quick determination of
threats is essential.Comment: 3 pages, 3 figures, submitted to conf. record of 2014 IEEE Nucl. Sci.
Symposium, Seattl
Summary and Outlook of the International Workshop on Aging Phenomena in Gaseous Detectors (DESY, Hamburg, October, 2001)
High Energy Physics experiments are currently entering a new era which
requires the operation of gaseous particle detectors at unprecedented high
rates and integrated particle fluxes. Full functionality of such detectors over
the lifetime of an experiment in a harsh radiation environment is of prime
concern to the involved experimenters. New classes of gaseous detectors such as
large-scale straw-type detectors, Micro-pattern Gas Detectors and related
detector types with their own specific aging effects have evolved since the
first workshop on wire chamber aging was held at LBL, Berkeley in 1986. In
light of these developments and as detector aging is a notoriously complex
field, the goal of the workshop was to provide a forum for interested
experimentalists to review the progress in understanding of aging effects and
to exchange recent experiences. A brief summary of the main results and
experiences reported at the 2001 workshop is presented, with the goal of
providing a systematic review of aging effects in state-of-the-art and future
gaseous detectors.Comment: 14 pages, 2 pictures. Presented at the IEEE Nuclear Science Symposium
and Medical Imaging Conference, November 4-10, 2001, San Diego, USA.
Submitted to IEEE Trans. Nucl. Sci (IEEE-TNS
Printing out Particle Detectors with 3D-Printers - a Potentially Transformational Advance for HEP Instrumentation
Abstract -This white paper suggests posing a "grand challenge" to the HEP instrumentation community, i.e. the aggressive development of additive manufacturing, also known as 3D-printing, for the production of particle detectors in collaboration with industry. This notion is an outcome of discussions within the instrumentation frontier group during the 2013 APS-DPF Snowmass summer study conducted by the U.S. HEP community. Improvements of current industrial 3D-printing capabilities by one to two orders of magnitude in terms of printing resolution, speed, and object size together with developing the ability to print composite materials could enable the production of any desired 3D detector structure directly from a digital model. Current industrial 3D-printing capabilities are briefly reviewed and contrasted with capabilities desired for printing detectors for particle physics, with micro-pattern gaseous detectors used as a first example. A significant impact on industrial technology could be expected if HEP were to partner with industry in taking on such a challenge
A Hadron Blind Detector for the PHENIX Experiment
A novel Hadron Blind Detector (HBD) has been developed for an upgrade of the
PHENIX experiment at RHIC. The HBD will allow a precise measurement of
electron-positron pairs from the decay of the light vector mesons and the
low-mass pair continuum in heavy-ion collisions. The detector consists of a 50
cm long radiator filled with pure CF4 and directly coupled in a windowless
configuration to a triple Gas Electron Multiplier (GEM) detector with a CsI
photocathode evaporated on the top face of the first GEM foil.Comment: 4 pages, 3 figures, Quark Matter 2005 conference proceeding
The Outer Tracker Detector of the HERA-B Experiment Part I: Detector
The HERA-B Outer Tracker is a large system of planar drift chambers with
about 113000 read-out channels. Its inner part has been designed to be exposed
to a particle flux of up to 2.10^5 cm^-2 s^-1, thus coping with conditions
similar to those expected for future hadron collider experiments. 13
superlayers, each consisting of two individual chambers, have been assembled
and installed in the experiment. The stereo layers inside each chamber are
composed of honeycomb drift tube modules with 5 and 10 mm diameter cells.
Chamber aging is prevented by coating the cathode foils with thin layers of
copper and gold, together with a proper drift gas choice. Longitudinal wire
segmentation is used to limit the occupancy in the most irradiated detector
regions to about 20 %. The production of 978 modules was distributed among six
different laboratories and took 15 months. For all materials in the fiducial
region of the detector good compromises of stability versus thickness were
found. A closed-loop gas system supplies the Ar/CF4/CO2 gas mixture to all
chambers. The successful operation of the HERA-B Outer Tracker shows that a
large tracker can be efficiently built and safely operated under huge radiation
load at a hadron collider.Comment: 28 pages, 14 figure
Construction and Performance of Large-Area Triple-GEM Prototypes for Future Upgrades of the CMS Forward Muon System
At present, part of the forward RPC muon system of the CMS detector at the
CERN LHC remains uninstrumented in the high-\eta region. An international
collaboration is investigating the possibility of covering the 1.6 < |\eta| <
2.4 region of the muon endcaps with large-area triple-GEM detectors. Given
their good spatial resolution, high rate capability, and radiation hardness,
these micro-pattern gas detectors are an appealing option for simultaneously
enhancing muon tracking and triggering capabilities in a future upgrade of the
CMS detector. A general overview of this feasibility study will be presented.
The design and construction of small (10\times10 cm2) and full-size trapezoidal
(1\times0.5 m2) triple-GEM prototypes will be described. During detector
assembly, different techniques for stretching the GEM foils were tested.
Results from measurements with x-rays and from test beam campaigns at the CERN
SPS will be shown for the small and large prototypes. Preliminary simulation
studies on the expected muon reconstruction and trigger performances of this
proposed upgraded muon system will be reported.Comment: 7 pages, 25 figures, submitted for publication in conference record
of the 2011 IEEE Nuclear Science Symposium, Valencia, Spai
An overview of the design, construction and performance of large area triple-GEM prototypes for future upgrades of the CMS forward muon system
GEM detectors are used in high energy physics experiments given their good spatial resolution, high rate capability and radiation hardness. An international collaboration is investigating the possibility of covering the 1.6 < vertical bar eta vertical bar < 2.4 region of the CMS muon endcaps with large-area triple-GEM detectors. The CMS high-eta area is actually not fully instrumented, only Cathode Strip Chamber (CSC) are installed. The vacant area presents an opportunity for a detector technology able to to cope with the harsh radiation environment; these micropattern gas detectors are an appealing option to simultaneously enhance muon tracking and triggering capabilities in a future upgrade of the CMS detector. A general overview of this feasibility study is presented. Design and construction of small (10cm x 10cm) and full-size trapezoidal (1m x 0.5m) triple-GEM prototypes is described. Results from measurements with x-rays and from test beam campaigns at the CERN SPS is shown for the small and large prototypes. Preliminary simulation studies on the expected muon reconstruction and trigger performances of this proposed upgraded muon system are reported
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