18 research outputs found
Muon tomography effectiveness in detecting orphan sources in scrap metal
The detection of sealed orphan sources inside scrap metal transportation is a crucial concern for the steel industry, because an accidental melting of radioactive material can produce severe environmental harm. The technique of muon tomography appears to be suitable for this purpose, because it allows to discriminate high-Z materials, measuring multiple scattering of cosmic ray muons crossing the cargo. A European project (RFSR-CT-2010-000033) to exploit this
technique started in 2010 and finished in 2012. The aim of the project was to design an inspection portal able to detect lead-shielded radioactive sources hidden in scrap metal containers using cosmic rays. The reconstruction algorithms and their performances were studied in a full simulated environment
Direct current measurements of the SPIDER beam: a comparison to existing beam diagnostics
For negative ion beam sources there are several methods of measuring the
accelerated beam current, most commonly electrical measurements at the power
supply and calorimetric measurements. On SPIDER, the ITER Heating Neutral Beam
full-scale beam source prototype, electrical measurements at the acceleration
grid power supply (AGPS) are complemented by polarizing the diagnostic
calorimeter STRIKE to provide an additional electrical measurement of the
accelerated current. This is in addition to the calorimetric measurements
provided by STRIKE. These diagnostics give differing measurements of the beam
current. Exploiting the reduced number of open apertures on SPIDER a new beam
diagnostic has been installed to measure the individual beamlet currents
directly. The so called Beamlet Current Monitor (BCM) has been used to measure
the current of five beamlets during the most recent SPIDER campaign. This work
compares the BCM current to the electrical measurements at the AGPS and STRIKE.
The average BCM current agrees well with the STRIKE electrical measurements,
indicating that the AGPS overestimates the beam current. The individual
beamlets are compared to the STRIKE calorimetric measurements, showing similar
current trends with the source parameters
Precision measurements of Linear Scattering Density using Muon Tomography
We demonstrate that muon tomography can be used to precisely measure the
properties of various materials. The materials which have been considered have
been extracted from an experimental blast furnace, including carbon (coke) and
iron oxides, for which measurements of the linear scattering density relative
to the mass density have been performed with an absolute precision of 10%. We
report the procedures that are used in order to obtain such precision, and a
discussion is presented to address the expected performance of the technique
when applied to heavier materials. The results we obtain do not depend on the
specific type of material considered and therefore they can be extended to any
application.Comment: 16 pages, 4 figure
Noise reduction in muon tomography for detecting high density objects
The muon tomography technique, based on multiple Coulomb scattering of cosmic
ray muons, has been proposed as a tool to detect the presence of high density
objects inside closed volumes. In this paper a new and innovative method is
presented to handle the density fluctuations (noise) of reconstructed images, a
well known problem of this technique. The effectiveness of our method is
evaluated using experimental data obtained with a muon tomography prototype
located at the Legnaro National Laboratories (LNL) of the Istituto Nazionale di
Fisica Nucleare (INFN). The results reported in this paper, obtained with real
cosmic ray data, show that with appropriate image filtering and muon momentum
classification, the muon tomography technique can detect high density
materials, such as lead, albeit surrounded by light or medium density material,
in short times. A comparison with algorithms published in literature is also
presented
Muon tomography effectiveness in detecting orphan sources in scrap metal
The detection of sealed orphan sources inside scrap metal trans-
portation is a crucial concern for the steel industry, because an accidental melting
of radioactive material can produce severe environmental harm. The technique of
muon tomography appears to be suitable for this purpose, because it allows to
discriminate high-Z materials, measuring multiple scattering of cosmic ray muons
crossing the cargo. A European project (RFSR-CT-2010-000033) to exploit this
technique started in 2010 and finished in 2012. The aim of the project was to de-
sign an inspection portal able to detect lead-shielded radioactive sources hidden in
scrap metal containers using cosmic rays. The reconstruction algorithms and their
performances were studied in a full simulated environment
Muography of different structures using muon scattering and absorption algorithms
In recent decades, muon imaging has found a plethora of applications in many fields. This technique succeeds to infer the density distribution of big inaccessible structures where conventional techniques cannot be used. The requirements of different applications demand specific implementations of image reconstruction algorithms for either multiple scattering or absorption-transmission data analysis, as well as noise-suppression filters and muon momentum estimators. This paper presents successful results of image reconstruction techniques applied to simulated data of some representative applications. In addition to well-known reconstruction methods, a novel approach, the so-called ÎĽCT, is proposed for the inspection of spent nuclear fuel canisters. Results obtained based on both ÎĽCT and the maximum-likelihood expectation maximization reconstruction algorithms are presented.This article is part of the Theo Murphy meeting issue 'Cosmic-ray muography'
A portable control and data acquisition solution using EPICS, MARTe and MDSplus
A modern Control and Data Acquisition System (CODAS) must provide an integrated management of supervision, data acquisition and real-time control and a data centric view of the system combining raw, elaborated and configuration data. These requirements have been addressed by the CODAS system of the SPIDER experiment in the ITER Neutral Beam Test Facility. The solution adopted in SPIDER CODAS integrates, by means of few interface components, three frameworks used in nuclear fusion and accelerator communities. A further refinement has recently started, aiming at providing a solution that is complete and generic, and, as such, easily portable to new applications, ranging from small systems to future fusion experiments. The refined system described in the paper will be deployed in the ECT-FALCON Test Facility, used to test the ITER EC launcher components and the European Gyrotron prototype. Its implementation in other test facilities is foreseen, in order to provide a fast track to the development of complete and integrated control and data acquisition
Expectation-propagation for weak radionuclide identification at radiation portal monitors
Noise reduction in muon tomography for detecting high density objects
The muon tomography technique, based on multiple Coulomb scattering of cosmic ray muons, has been proposed as a tool to detect the presence of high density objects inside closed volumes. In this paper a new and innovative method is presented to handle the density fluctuations (noise) of reconstructed images, a well known problem of this technique. The effectiveness of our method is evaluated using experimental data obtained with a muon tomography prototype located at the Legnaro National Laboratories (LNL) of the Istituto Nazionale di Fisica Nucleare (INFN). The results reported in this paper, obtained with real cosmic ray data, show that with appropriate image filtering and muon momentum classification, the muon tomography technique can detect high density materials, such as lead, albeit surrounded by light or medium density material, in short times. A comparison with algorithms published in literature is also presented