Characterization of a neutron imaging setup at the INES facility (original) (raw)

Neutron radiography studies for Cultural Heritage within the neu_ART project

2011

One of the aims of neu_ART project is to investigate the capability of fast neutron imaging applied on artefacts of interest for cultural heritage. Compact systems based on D-D or D-T fast neutron sources could be installed in certificated laboratories near restoration centers as diagnostic tools to plan the restoration work. This paper presents preliminary studies carried out at fast (NECTAR) and thermal (INES) neutron facilities. Custom samples of different thicknesses, internal structures and material compositions were analyzed, together with artistic objects to compare the performance of fast and thermal neutron radiography. We focused our studies on the neutron penetration into metals, as bronze, iron, and brass. A detailed analysis of the results is presented and compared with digital X-ray radiography. These two complementary techniques can be integrated to fully characterize the objects under study.

The study of cultural heritage relevant objects by means of neutron imaging techniques

Insight - Non-Destructive Testing and Condition Monitoring, 2014

The use of non-invasive and non-destructive methods is highly relevant for cultural heritage objects in particular, due to their uniqueness and the often high cost of material as well as immaterial value. It is, however, of great importance to gain a simple overview of their material distribution, the manufacturing techniques, the provenance and the current condition (for example the determination of possible damage) by transmission imaging techniques. While X-ray imaging is often sufficient for such investigations, there are numerous cases where the method reaches its limits. Here, the complementarities of neutrons applied in a similar manner can provide new insights into the object studied. The better transmission for metals and the higher contrast for organic materials can already be exploited in the simple neutron radiography mode. More advanced are the neutron tomography methods, which are available at the neutron imaging facilities of the Paul Scherrer Institut (PSI) on a wide dimensional scale range. Virtual slices through the objects at arbitrary positions enable deeper perceptions and also dimensional determinations in full 3D. Further methodical improvements have been developed. Narrowing the neutron energy band allows information on the microcrystalline structure to be obtained directly, and using phase-contrast and dark-field techniques by means of a grating interferometer device enables a deeper understanding of the material compositions and structures. The examples in this paper are chosen to demonstrate the application range of neutron imaging and the performance of the different set-ups.

A neutron tomographic system developed at the Rome research reactor

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1994

A third-generation neutron tomographic system, mainly used for nondestructive evaluation on small hydrogenated samples, has been recently set up at the ENEA TRIGA RC II research reactor in Rome, Italy. This reactor operates at a nominal power of 1 MW and produces a thermal beam of about 2 X 10 5 cm -2 s -1 with a collimation ratio LID of about 30 . The object to be examined is viewed by a Thomson CSF neutron image intensifier coupled to a cooled CCD (Charge Coupled Device) camera equipped with a sensitive array of 192 X 165 pixels, each acting as an equivalent elementary neutron detector . The entire set of projections (usually 120) needed for the examination is acquired in about 90 min, as the system operates in a rotate-only configuration with parallel beam . The reconstruction software used is a development of the Donner Package for Reconstruction Tomography, specifically modified in order to deal with third-generation algorithms using the projection images produced by the CCD camera. At present, the total reconstruction time to obtain the full set of 165 slices of 192 X 192 pixels each is about 60 min on a standard Solbourne SPARC 4 multi-user workstation .

Neutron radiography using neutron imaging plate

Applied Radiation and Isotopes, 2010

The aims of this research are to study properties of a neutron imaging plate (NIP) and to test it for use in nondestructive testing (NDT) of materials. The experiments were carried out by using a BAS-ND 2040 Fuji NIP and a neutron beam from the Thai Research Reactor TRR-1/M1. The neutron intensity and Cd ratio at the specimen position were approximately 9 Â 10 5 ns/cm 2 s and 100 respectively. It was found that the photostimulated luminescence (PSL) readout of the imaging plate was directly proportional to the exposure time and approximately 40 times faster than the conventional NR using Gd converter screen/X-ray film technique. The sensitivities of the imaging plate to slow neutron and to Ir-192 gamma-rays were found to be approximately 4.2 Â 10 À 3 PSL/mm 2 per neutron and 6.7 Â 10 À 5 PSL/mm 2 per gamma-ray photon respectively. Finally, some specimens containing light elements were selected to be radiographed with neutrons using the NIP and the Gd converter screen/X-ray film technique. The image quality obtained from the two recording media was found to be comparable.

Neutron Imaging from a Museum Perspective

2017

Research is one of the three principal activities of a museum, besides education and conservation of the collections. All three have to be understood in the widest possible sense. Scientific research on the objects would in turn only represent a relatively small part of a museum's overall research activities, the focus being usually on historical, art historical, archaeological or other research directly in line with the museum's subject area. Neutron imaging and analysis of cultural artefacts are relatively new methods and only represent therefore a marginal technique on the fringe of a museum's activities. Why would under these circumstances neutron imaging be interesting to a museum? This paper presents examples from the Geneva Ethnographic Museum illustrating how looking inside an object contributes to our understanding of the museum's collections, and where, despite the exceptional logistical effort required for the analysis, neutron imaging becomes important or...

Applications of various imaging techniques in neutron radiography at BARC, Trombay

Neutron radiography systems based on Gd, Dy and In metallic foils and X-ray films have been used at this centre since early seventies for various NDT and R&D work in nuclear, defense and aerospace industries. In recent years use of digital detection systems such as neutron scintillator and CCD based imaging systems and photostimulated luminescence based phosphor imaging plate systems have been introduced in our work. This has enabled to achieve higher sensitivities and dynamic ranges of recording radiographs with acceptable spatial resolution. These new systems provide digital image information and are more convenient for quantitative evaluations. At BARC these new techniques have been used in variety of radiography techniques such as conventional neutron radiography (NR), neutron induced beta radiography (NIBR), hydrogen sensitive epithermal neutron radiography (HYSEN) using Apsara, CIRUS and Dhruva reactors as neutron sources. The details of the work done are described in this paper.

NEUTRON IMAGING TECHNIQUES APPLIED TO STUDIES IN THE ARCHAEOLOGICAL AND CULTURAL HERITAGE FIELDS

M. A. Stanoyev-Perreira, J. G. Marques, J. P. Santos, M. I. Prudencio, C. I. Burbidge, 2013

Neutron imaging techniques are non-destructive tools that can help to understand the processes involved in manufacturing and restoration of cultural heritage artefacts. The interaction of neutrons with matter is markedly different from the interaction of other types of radiation, enhancing features where light elements are involved. Imaging of relative levels of neutron absorption is based on photography of scintillations produced in a ZnS screen doped with LiF, where Li is used as a neutron to charged particle converter. In this work we present studies made in the Portuguese Research Reactor applied to the characterization of restorations with resin, absorption of natural oils, and water retention.