Physics Procedia最新文献

{"title":"Recent Applications of Neutron Imaging Methods","authors":"E. Lehmann,&nbsp;D. Mannes,&nbsp;A. Kaestner,&nbsp;C. Grünzweig","doi":"10.1016/j.phpro.2017.06.055","DOIUrl":"10.1016/j.phpro.2017.06.055","url":null,"abstract":"<div><p>The methodical progress in the field of neutron imaging is visible in general but on different levels in the particular labs. Consequently, the access to most suitable beam ports, the usage of advanced imaging detector systems and the professional image processing made the technique competitive to other non-destructive tools like X-ray imaging. Based on this performance gain and by new methodical approaches several new application fields came up – in addition to the already established ones. Accordingly, new image data are now mostly in the third dimension available in the format of tomography volumes. The radiography mode is still the basis of neutron imaging, but the extracted information from superimposed image data (like for a grating interferometer) enables completely new insights. In the consequence, many new applications were created.</p></div>","PeriodicalId":20407,"journal":{"name":"Physics Procedia","volume":"88 ","pages":"Pages 5-12"},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.phpro.2017.06.055","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76551755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Results from a Prototype Proton-CT Head Scanner","authors":"R.P. Johnson ,&nbsp;V.A. Bashkirov ,&nbsp;G. Coutrakon ,&nbsp;V. Giacometti ,&nbsp;P. Karbasi ,&nbsp;N.T. Karonis ,&nbsp;C.E. Ordoñez ,&nbsp;M. Pankuch ,&nbsp;H.F.-W. Sadrozinski ,&nbsp;K.E. Schubert ,&nbsp;R.W. Schulte","doi":"10.1016/j.phpro.2017.09.060","DOIUrl":"10.1016/j.phpro.2017.09.060","url":null,"abstract":"<div><p>We are exploring low-dose proton radiography and computed tomography (pCT) as techniques to improve the accuracy of proton treatment planning and to provide artifact-free images for verification and adaptive therapy at the time of treatment. Here we report on comprehensive beam test results with our prototype pCT head scanner. The detector system and data acquisition attain a sustained rate of more than a million protons individually measured per second, allowing a full CT scan to be completed in six minutes or less of beam time. In order to assess the performance of the scanner for proton radiography as well as computed tomography, we have performed numerous scans of phantoms at the Northwestern Medicine Chicago Proton Center including a custom phantom designed to assess the spatial resolution, a phantom to assess the measurement of relative stopping power, and a dosimetry phantom. Some images, performance, and dosimetry results from those phantom scans are presented together with a description of the instrument, the data acquisition system, and the calibration methods.</p></div>","PeriodicalId":20407,"journal":{"name":"Physics Procedia","volume":"90 ","pages":"Pages 209-214"},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.phpro.2017.09.060","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77457750","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"X-ray Scattering in the Shielding of Industrial Irradiation Facilities","authors":"Marshall R. Cleland,&nbsp;Richard A. Galloway,&nbsp;Dylan F. Brown","doi":"10.1016/j.phpro.2017.09.049","DOIUrl":"10.1016/j.phpro.2017.09.049","url":null,"abstract":"<div><p>When high-energy X-ray photons impinge on thick shields, most of the incident energy is absorbed in the shielding material, but some of it is deflected sideways or backward into the treatment room. This effect is important in facilities that have openings in the shields to allow the passage of products through the irradiation zone or mazes to provide access into this zone for operating personnel. Multiple scattering events in these openings can reduce the energies of the photons and the dose rates of the residual radiation to comply with applicable safety regulations. Basic equations and examples are presented to show how these scattering effects can be evaluated in the designs of new irradiation facilities.</p></div>","PeriodicalId":20407,"journal":{"name":"Physics Procedia","volume":"90 ","pages":"Pages 151-156"},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.phpro.2017.09.049","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86291140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Freeware Path to Neutron Computed Tomography","authors":"Burkhard Schillinger ,&nbsp;Aaron E. Craft","doi":"10.1016/j.phpro.2017.06.047","DOIUrl":"10.1016/j.phpro.2017.06.047","url":null,"abstract":"<div><p>Neutron computed tomography has become a routine method at many neutron sources due to the availability of digital detection systems, powerful computers and advanced software. The commercial packages Octopus by Inside Matters and VGStudio by Volume Graphics have been established as a quasi-standard for high-end computed tomography. However, these packages require a stiff investment and are available to the users only on-site at the imaging facility to do their data processing. There is a demand from users to have image processing software at home to do further data processing; in addition, neutron computed tomography is now being introduced even at smaller and older reactors. Operators need to show a first working tomography setup before they can obtain a budget to build an advanced tomography system. Several packages are available on the web for free; however, these have been developed for X-rays or synchrotron radiation and are not immediately useable for neutron computed tomography. Three reconstruction packages and three 3D-viewers have been identified and used even for Gigabyte datasets. This paper is not a scientific publication in the classic sense, but is intended as a review to provide searchable help to make the described packages usable for the tomography community. It presents the necessary additional preprocessing in ImageJ, some workarounds for bugs in the software, and undocumented or badly documented parameters that need to be adapted for neutron computed tomography. The result is a slightly complicated, but surprisingly high-quality path to neutron computed tomography images in 3D, but not a replacement for the even more powerful commercial software mentioned above.</p></div>","PeriodicalId":20407,"journal":{"name":"Physics Procedia","volume":"88 ","pages":"Pages 348-353"},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.phpro.2017.06.047","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72949888","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Samples to Determine the Resolution of Neutron Radiography and Tomography","authors":"A.P. Kaestner ,&nbsp;Z. Kis ,&nbsp;M.J. Radebe ,&nbsp;D. Mannes ,&nbsp;J. Hovind ,&nbsp;C. Grünzweig ,&nbsp;N. Kardjilov ,&nbsp;E.H. Lehmann","doi":"10.1016/j.phpro.2017.06.036","DOIUrl":"10.1016/j.phpro.2017.06.036","url":null,"abstract":"<div><p>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 with Ti spheres of increasing dimensions in each vial. Ti was chosen since it provides sufficient contrast while the transmission is still guaranteed. The first resolution criterion was to determine from which vial that the spheres can be uniquely identified as spheres. More complex analysis would involve measuring the volume of the spheres or even to compute the edge spread function analogous to the method with the knife-edge for radiographs. For the edge analysis, a larger Ti sphere was considered. Using a sphere for the edge spread function analysis allowed for determination of the resolution in any direction. Images acquired using the different test items are included and methods to perform the analysis required to quantify the resolution from the images are proposed.</p></div>","PeriodicalId":20407,"journal":{"name":"Physics Procedia","volume":"88 ","pages":"Pages 258-265"},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.phpro.2017.06.036","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89006817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measuring Surface Bulk Elemental Composition on Venus","authors":"Jeffrey S. Schweitzer ,&nbsp;Ann M. Parsons ,&nbsp;Jim Grau ,&nbsp;David J. Lawrence ,&nbsp;Timothy P. McClanahan ,&nbsp;Jeffrey Miles ,&nbsp;Patrick Peplowski ,&nbsp;Luke Perkins ,&nbsp;Richard Starr","doi":"10.1016/j.phpro.2017.09.056","DOIUrl":"10.1016/j.phpro.2017.09.056","url":null,"abstract":"<div><p>Bulk elemental composition measurements of the subsurface of Venus are challenging because of the extreme surface environment (462 ˚C, 93 bars pressure). Instruments provided by landed probes on the surface of Venus must therefore be enclosed in a pressure vessel. The high surface temperatures require a thermal control system that keeps the instrumentation and electronics within their operating temperature range for as long as possible. Currently, Venus surface probes can operate for only a few hours. It is therefore crucial that the lander instrumentation be able to make statistically significant measurements in a short time. An instrument is described that can achieve such a measurement over a volume of thousands of cubic centimeters of material by using high energy penetrating neutron and gamma radiation. The instrument consists of a Pulsed Neutron Generator (PNG) and a Gamma-Ray Spectrometer (GRS). The PNG emits isotropic pulses of 14.1 MeV neutrons that penetrate the pressure vessel walls, the dense atmosphere and the surface rock. The neutrons induce nuclear reactions in the rock to produce gamma rays with energies specific to the element and nuclear process involved. Thus the energies of the detected gamma rays identify the elements present and their intensities provide the abundance of each element. The GRS spectra are analyzed to determine the Venus elemental composition from the spectral signature of individual major, minor, and trace radioactive elements. As a test of such an instrument, a Schlumberger Litho Scanner<span>¹</span> oil well logging tool was used in a series of experiments at NASA's Goddard Space Flight Center. The Litho Scanner tool was mounted above large (1.8 m x 1.8 m x .9 m) granite and basalt monuments and made a series of one-hour elemental composition measurements in a planar geometry more similar to a planetary lander measurement. Initial analysis of the results shows good agreement with target elemental assays.</p></div>","PeriodicalId":20407,"journal":{"name":"Physics Procedia","volume":"90 ","pages":"Pages 180-186"},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.phpro.2017.09.056","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90806433","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Special Features of Copper(II) Detection in Aqueous Solutions","authors":"A.A. Sergeev ,&nbsp;A.Y. Mironenko ,&nbsp;A.A. Leonov ,&nbsp;A.E. Nazirov ,&nbsp;S.S. Voznesenskiy ,&nbsp;S.Y. Bratskaya ,&nbsp;Y.N. Kulchin","doi":"10.1016/j.phpro.2017.01.007","DOIUrl":"10.1016/j.phpro.2017.01.007","url":null,"abstract":"<div><p>New approach to organize fluorescent sensor system for determination of metal ions in aqueous solutions was presented. The approach is based on modification of hydrophilic polymer with sensitive fluorescent indicators. Possibility to register Cu2+ ions by analyzing of luminescence excitation spectra and lifetimes of the sensitive coating is presented.</p></div>","PeriodicalId":20407,"journal":{"name":"Physics Procedia","volume":"86 ","pages":"Pages 152-154"},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.phpro.2017.01.007","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91200071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measurements of the Effective Atomic Numbers of Alloys using Thick-Target Bremsstrahlung Intensities","authors":"S. Czarnecki,&nbsp;A. Short,&nbsp;S. Williams","doi":"10.1016/j.phpro.2017.09.017","DOIUrl":"10.1016/j.phpro.2017.09.017","url":null,"abstract":"<div><p>We have investigated the accuracy with which the effective atomic number (Z_eff) of an alloy can be measured using the intensity of the thick-target bremsstrahlung produced by low-energy electrons incident on the alloy target. The experiments involved 5 keV-electron beams incident on thick brass, Ni/Fe/Mo, C-276, and stainless steel targets. By comparing the data obtained using alloy targets to the data obtained using a high-purity aluminum target and data from a previous study performed by our group (in which the Z-dependence of thick-target bremsstrahlung was studied), the Z_eff values of the alloy targets were measured and compared to theoretical values. While the experimental Z_eff values of the stainless steel and Ni/Fe/Mo targets were in relatively good agreement with the theoretical values, the experimental Z_eff values of the brass and C-276 targets were not.</p></div>","PeriodicalId":20407,"journal":{"name":"Physics Procedia","volume":"90 ","pages":"Pages 41-46"},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.phpro.2017.09.017","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84115407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Technical Aspects of Delivering Simultaneous Dual and Triple Ion Beams to a Target at the Michigan Ion Beam Laboratory","authors":"O. Toader,&nbsp;F. Naab,&nbsp;E. Uberseder,&nbsp;T. Kubley,&nbsp;S. Taller,&nbsp;G. Was","doi":"10.1016/j.phpro.2017.09.039","DOIUrl":"10.1016/j.phpro.2017.09.039","url":null,"abstract":"<div><p>The Michigan Ion Beam Laboratory (MIBL) at the University of Michigan in Ann Arbor, Michigan, USA, plays a significant role in supporting the mission of the U.S. DOE Office of Nuclear Energy. MIBL is a charter laboratory of the NSUF (National Scientific User Facility – US DoE) and hosts users worldwide. The laboratory has evolved from a single accelerator laboratory to a highly versatile facility with three accelerators (3 MV Tandem, a 400<!--> <!-->kV Ion Implanter and a 1.7 MV Tandem), seven beam lines and five target chambers that together, provide unique capabilities to capture the extreme environment experienced by materials in reactor systems. This capability now includes simultaneous multiple (dual, triple) ion irradiations, an irradiation accelerated corrosion cell, and soon, in-situ dual beam irradiation in a transmission electron microscope (TEM) for the study of radiation damage coupled with injection of transmutation elements. The two beam lines that will connect to the 300<!--> <!-->kV FEI Tecnai G2 F30 microscope are expected to be operational by the end of 2017. Multiple simultaneous ion beam experiments involving light and heavy ions are already in progress. This paper will outline the current equipment and will focus on the new capability of running dual and triple ion beam experiments.</p></div>","PeriodicalId":20407,"journal":{"name":"Physics Procedia","volume":"90 ","pages":"Pages 385-390"},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.phpro.2017.09.039","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89868767","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Single-shot Laser-assisted Nanofabrication of Plasmonic Nanorings","authors":"A.V. Nepomnyashchii ,&nbsp;A.A. Kuchmizhak ,&nbsp;S.O. Gurbatov ,&nbsp;O.B. Vitrik ,&nbsp;Yu.N. Kulchin","doi":"10.1016/j.phpro.2017.01.002","DOIUrl":"10.1016/j.phpro.2017.01.002","url":null,"abstract":"<div><p>Simple high-performing two-step technique for fabrication different functional plasmonic nanostructures including nanorods, separated and crossed nanorings, as well as more complex hybrid structures on both glass and silicon substrates was proposed. In this technique the noble metal film covering bulk glass or silicon substrates is irradiated by single tightly focused nanosecond laser pulse followed by slow polishing of the fabricated nanostructures by accelerated argon ion (Ar⁺) beam. Nanosecond laser pulse locally modifies its initial thickness of metal film through the initiation of ultrafast melting and subsequent hydrodynamic processes, while the following Ar⁺ polishing reveals only the features of its topography - plasmonic structures on the glass/Si substrate. We demonstrate that both the type and lateral size of the resulting functional plasmonic nanostructure are determined by the pulse energy, metal film thickness as well as the optical spot size, while subsequent Ar⁺ polishing allows varying the height of the resulting nanostructures. The proposed simple two-step high-throughput technique represents the next step towards direct lased-induced fabrication of complex functional plasmonic nanostructures and is well-suited for both large-scale fabrication of ordered arrays comprising hundreds of nanoelements and single nanostructure at a given point on the sample surface.</p></div>","PeriodicalId":20407,"journal":{"name":"Physics Procedia","volume":"86 ","pages":"Pages 3-10"},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.phpro.2017.01.002","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90662088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}