Bimodal Imaging at ICON Using Neutrons and X-rays
Publication date: 2017 Source:Physics Procedia, Volume 88 Author(s): A.P. Kaestner, J. Hovind, P. Boillat, C. Muehlebach, C. Carminati, M. Zarebanadkouki, E.H. Lehmann For experiments with low contrast between the relevant features it can be beneficial to add a second modality to reduce ambiguity. At Paul Scherrer Institut the two neutron imaging facilities NEUTRA (thermal neutrons) and ICON (cold neutrons) we have installed X-ray beamlines for on-site bimodal imaging with neutrons and X-rays. This allows us to leave the sample untouched in the sample environment throughout an experiment and to reduce the waiting ...
Source: Physics Procedia - June 24, 2017 Category: Physics Source Type: research
Reliability Estimation of Neutron Resonance Thermometry Using Tantalum and Tungsten
Publication date: 2017 Source:Physics Procedia, Volume 88 Author(s): Tetsuya Kai, Kosuke Hiroi, Yuhua Su, Takenao Shinohara, Joseph D. Parker, Yoshihiro Matsumoto, Hirotoshi Hayashida, Mariko Segawa, Takeshi Nakatani, Kenichi Oikawa, Shuoyuan Zhang, Yoshiaki Kiyanagi The reliability of neutron resonance thermometry was discussed based on measurements of neutrons transmitted through tantalum (0.1mm thick) and tungsten (1mm thick) indicators at 26, 96, 189, and 285 degrees Celsius using the energy-resolved neutron imaging system, RADEN, at the Japan Proton Accelerator Complex (J-PARC). The intensity of transmit...
Source: Physics Procedia - June 24, 2017 Category: Physics Source Type: research
Calibration and Correction Method of the Deflection Angle of Rotation Axis Projection on Neutron Tomography
Publication date: 2017 Source:Physics Procedia, Volume 88 Author(s): Zhilong Ji, Qiang Lin, Xu Han, Jiawei Liu, Wen Zhang, Min Yang For neutron tomography, reconstruction accuracy greatly relies on exact registration of the projection and the back-projection coordinate system. Since the manufacturing and installing errors of mechanical components make the rotation axis projected in CCD camera deflect a certain angle, a mismatch between the projection coordinate and the detector coordinate will be caused consequently, resulting in obvious artifacts on the reconstructed images. In this paper, a calibration and correc...
Source: Physics Procedia - June 24, 2017 Category: Physics Source Type: research
Sparse-view Reconstruction of Dynamic Processes by Neutron Tomography
Publication date: 2017 Source:Physics Procedia, Volume 88 Author(s): Hu Wang, Anders Kaestner, Yubin Zou, Yuanrong Lu, Zhiyu Guo As for neutron tomography, hundreds of projections over the range of 0-180 degrees are required to reconstruct the attenuation matrix with the traditional filtered back projection (FBP) algorithm, and the total acquisition time can reach several hours. This poor temporal resolution constrains that neutron tomography is only feasible to investigate static or quasi-static process. Reducing the number of projections is a possible way to improve the temporal resolution, which however highly re...
Source: Physics Procedia - June 24, 2017 Category: Physics Source Type: research
Edge Enhancement Investigations by Means of Experiments and Simulations
Publication date: 2017 Source:Physics Procedia, Volume 88 Author(s): E. Lehmann, M. Schulz, Y. Wang, A. Tartaglione Standard neutron imaging procedures are based on the “shadow” of the transmitted radiation, attenuated by the sample material. Under certain conditions significant deviations from pure transmission can be found in the form of enhancement or depression at the edges of the samples. These effects can limit the quantification process in the related regions. Otherwise, an enhancement and improvement of visibility can be achieved e.g. in defect analysis. In systematic studies we investigated the dependenc...
Source: Physics Procedia - June 24, 2017 Category: Physics Source Type: research
A Method for Neutron Scattering Quantification and Correction Applied to Neutron Imaging
Publication date: 2017 Source:Physics Procedia, Volume 88 Author(s): Marc Raventos, Ralph P. Harti, Eberhard Lehmann, Christian Grünzweig Either the composition, the thickness or the density of a sample can be derived, given the other two are known, by measuring the attenuation of a given incident radiation intensity through the sample. However, in the case of neutron imaging, the separation of the transmitted intensity from the scattered intensity using scintillator-based detection systems is yet to be solved. Several methods have been proposed for the correction of disturbing neutron scattering, but they are only ...
Source: Physics Procedia - June 24, 2017 Category: Physics Source Type: research
Which Resolution can be Achieved in Practice in Neutron Imaging Experiments? – A General View and Application on the Zr - ZrH2 and ZrO2 - ZrN Systems
Publication date: 2017 Source:Physics Procedia, Volume 88 Author(s): Mirco Grosse, Nikolay Kardjilov Current methodical developments improve the spatial resolution of neutron imaging facilities. Objects with dimensions down to several microns should be detectable. However, the minimum object size detectable depends not only on the facility hardware like detector resolution or neutron optics, but also on the attenuation contrast. In this paper the relation between illumination time needed, neutron contrast of the objects and their minimal size detectable is derived and an analysis of the minimal dimension of an object c...
Source: Physics Procedia - June 24, 2017 Category: Physics Source Type: research
Samples to Determine the Resolution of Neutron Radiography and Tomography
Publication date: 2017 Source:Physics Procedia, Volume 88 Author(s): A.P. Kaestner, Z. Kis, M.J. Radebe, D. Mannes, J. Hovind, C. Grünzweig, N. Kardjilov, E.H. Lehmann Knowing the resolution and effective pixel size of an imaging system is essential for dimensional and quantitative measurements. A collection of test devices was developed for neutron imaging that can be used to quantify pixel and voxel size, resolution of the imaging system, and beam divergence. The first set of devices is intended for measurements with radiographs using test patterns or an absorbing edge. For tomography, Al vials were filled wit...
Source: Physics Procedia - June 24, 2017 Category: Physics Source Type: research
Methodical Progress in Neutron Imaging at PSI
Publication date: 2017 Source:Physics Procedia, Volume 88 Author(s): E. Lehmann, M. Raventos, R.P. Harti, P. Trtik, A. Kaestner, D. Mannes, C. Grünzweig Within this paper we summarize new approaches for the utilization of neutron beams for imaging purposes. Whereas most of the methods are still based on the radiography mode - however now with higher performance with respect to spatial resolution, dynamic range and linearity (obtained often in short exposure time) - the new aspects of using polarized neutrons, the diffracted neutron signal or grating interferometers are linking towards neutron scattering investiga...
Source: Physics Procedia - June 24, 2017 Category: Physics Source Type: research
The Signal Chain - how the Removal of an Image Intensifier at the AERE Reactor in Bangladesh Improves Neutron Imaging
This article takes a look at the signal chain for neutron radiography and tries to give some help for estimating required statistics and exposure times. (Source: Physics Procedia)
Source: Physics Procedia - June 24, 2017 Category: Physics Source Type: research
Performance of Self-developing Radiography Films in LVR-15's Neutron Beams
Publication date: 2017 Source:Physics Procedia, Volume 88 Author(s): Jaroslav Soltes, Ladislav Viererbl, Vit Klupak, Miroslav Vins, Bozena Michalcova In the search for a suitable detector for demonstration neutron radiography measurements on the zero-power VR-1 training reactor at the Czech Technical University in Prague, some options were considered. Due to the reactor's low power and spatial limitations, an easy and practical solution had to be found. Self-developing films represent a flexible detection tool in x-ray imaging. Therefore, the goal of this study was to evaluate their potential for neutron detection. ...
Source: Physics Procedia - June 24, 2017 Category: Physics Source Type: research
Development of an in-situ SEOP 3He Neutron Spin Filter for Magnetic Imaging Techniques
In this study, we installed two in-situ SEOP systems as a neutron spin polarizer and analyzer providing a stable high-energy polarized neutron beam over several days. (Source: Physics Procedia)
Source: Physics Procedia - June 24, 2017 Category: Physics Source Type: research
A Neutron Detector with Submicron Spatial Resolution using Fine-grained Nuclear Emulsion
Publication date: 2017 Source:Physics Procedia, Volume 88 Author(s): N. Naganawa, S. Awano, M. Hino, M. Hirose, K. Hirota, H. Kawahara, M. Kitaguchi, K. Mishima, T. Nagae, H.M. Shimizu, S. Tasaki, A. Umemoto We developed a neutron detector with submicron spatial resolution by incorporating 6Li into a fine-grained nuclear emulsion. Upon exposure to thermal neutrons, tracks from neutron capture events were observed. The detector spatial resolution was estimated from their grain density. Detection efficiency was measured using the detector response to cold neutrons. (Source: Physics Procedia)
Source: Physics Procedia - June 24, 2017 Category: Physics Source Type: research
Experimental Evaluation of Neutron Absorption Grating Fabricated by Oblique Evaporation of Gadolinium for Phase Imaging
Publication date: 2017 Source:Physics Procedia, Volume 88 Author(s): Yoshichika Seki, Takenao Shinohara, Wakana Ueno, Joseph D. Parker, Tetsuo Samoto, Wataru Yashiro, Atsushi Momose For the neutron phase imaging with a Talbot-Lau interferometer, we have fabricated neutron absorption gratings with a pitch of 9μm by oblique evaporation of gadolinium. The performances of these gratings for the phase measurement were experimentally evaluated at RADEN in J-PARC, by observing the neutron transmission and the visibility of moiré fringe in the interferometer. A new analysis method using the wavelength-resolved neutron t...
Source: Physics Procedia - June 24, 2017 Category: Physics Source Type: research
Experiences with a New Shielding Material
Publication date: 2017 Source:Physics Procedia, Volume 88 Author(s): T. Bücherl, E. Calzada, S.Q. Liu, W. Stöwer, F. Kortmann, H. Größlhuber, Ch. Lierse von Gostomski Recent modifications of the NECTAR facility included the set-up of a new beam dump. One of its main components is based on a reusable shielding material developed at TUM. The provided base material was characterized and its advantages and limitations were investigated by simulation studies and by measurements. (Source: Physics Procedia)
Source: Physics Procedia - June 24, 2017 Category: Physics Source Type: research
