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Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 403
Author(s):  
Roxana Bugoi ◽  
Alexandra Ţârlea ◽  
Veronika Szilágyi ◽  
Ildikó Harsányi ◽  
Laurenţiu Cliante ◽  
...  

The chemical composition of 48 glass finds from Histria and Tomis, Romania, chiefly dated to the 1st–4th c. AD, was determined using prompt gamma activation analysis (PGAA) at the Budapest Neutron Centre (BNC). Most fragments have composition typical for the Roman naturally colored blue-green-yellow (RNCBGY) glass; Mn-colorless, Sb-colorless, and Sb–Mn colorless glass finds were evidenced, too. Several Foy Série 2.1 and Foy Série 3.2 glass fragments, as well as an HIMT and a plant ash glass sample, were identified in the studied assemblage. The archaeological evidence, the glass working waste items, and the samples with compositional patterns suggestive of recycling are proofs of the secondary glass working activities at Tomis during the Early Roman Empire period.


2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Katalin Bajnok ◽  
Zoltán Kovács ◽  
John Gait ◽  
Boglárka Maróti ◽  
Péter Csippán ◽  
...  

AbstractThis study presents the results of the petrographic and geochemical analyses of the entire pottery assemblage discovered at the sixth-century (AD) cemetery of Szólád, Western Hungary, associated with the Langobard era in the territory of the former Roman province of Pannonia. Szólád is one of the most prominent archaeological sites of this period, where prior studies have shown that the cemetery was used for ca. one or two generations by a migrating group of diverse genetic background. The present work is the first integrated typological and archaeological science pottery analysis from the early migration period (fifth to sixth century) Hungary. We applied polarising light optical microscopy (OM), prompt gamma activation analysis (PGAA), and neutron activation analysis (NAA) on all samples and, additionally, scanning electron microscopy equipped with energy dispersive spectrometry (SEM–EDS) on one selected sample. One main fabric group with three subgroups were defined by OM, to which the majority of the samples belong. This fabric group was characterised by aplastic inclusions derived from a carbonate-cemented sandstone typical of the environs of Szólád; therefore, the vessels of this fabric group appear to have been produced locally. The remaining four samples display a variety of unique, ungrouped, fabrics (loners) indicative of different recipes and/or the presence of pottery originating from outside of the region. Our study concludes that the community associated with the cemetery favoured burying pots with the deceased that stylistically resembled archaic “Elbe Germanic” traditions, but which were in fact made locally. However, in some cases, relationships with more distant territories and cultural traditions are also represented.


Author(s):  
K. Gmeling ◽  
T. Kocsis ◽  
J. Osan ◽  
Z. Kis ◽  
M. A. Pocsai ◽  
...  

The human consumption of humic acid is increasingly relevant therefore the knowledge of exact composition is essential. To make a step in that direction we present gap filling results obtained from three different element analytical investigations of humic acid extracted from fen peat examined in the Carpathian Basin. Prompt-gamma activation (PGAA), neutron activation analytical method (NAA) and X-ray fluorescence (XRF) analysis was carried out. After presenting and explaining the essence of used analytical methods we show some collected spectra and a table where all the concentration of the iden- tified elements are presented with the corresponding measurement errors. All together 42 elements were  identified. PACS.78.70.En, 78.70. Nx,78. 90.+t X-ray emission spectra and fluorescence, Neutroninelastic scattering, Other topics in optical properties, condensed matter aspect.


2021 ◽  
Author(s):  
Andrew Chacon ◽  
Marissa Kielly ◽  
Harley Rutherford ◽  
Daniel R. Franklin ◽  
Anita Caracciolo ◽  
...  

Abstract Neutron Capture Enhanced Particle Therapy (NCEPT) boosts the effectiveness of particle therapy by capturing thermal neutrons produced by beam-target nuclear interactions in and around the treatment site, using tumour-specific 10B or 157Gd-based neutron capture agents. Neutron captures release high-LET secondary particles together with prompt gamma photons with energies of 478 keV (10B) or 7.94 MeV (157Gd). A key requirement for NCEPT’s translation is the development of in vivo dosimetry techniques which can measure both the direct ion dose and the dose due to neutron capture. In this work, we report signatures which can be used to discriminate between photons resulting from neutron capture and those originating from other processes. A Geant4 Monte Carlo simulation study into timing and energy thresholds for discrimination of prompt gamma photons resulting from thermal neutron capture during NCEPT was conducted. Three simulated 300×300×300 mm3 cubic PMMA targets were irradiated by 4He or 12C ion beams with a spread out Bragg peak (SOBP) depth range of 60 mm; one target is homogeneous while the others include 10×10×10 mm3 neutron capture inserts (NCIs) of pure 10B or 157Gd located at the distal edge of the SOBP. The arrival times of photons and neutrons entering a simulated 50×50×50 mm3 ideal detector were recorded. The majority of photons resulting from neutron capture were found to arrive at the detector at least 60 ns later than photons created by other processes. A range of candidate detector and thermal neutron shielding materials were simulated, and detections meeting the proposed acceptance criteria (i.e. falling within the target energy window and arriving 60 ns post beam-off) were classified as true or false positives, depending on their origin. The ratio of true / false positives (RTF) was calculated; for targets with 10B and 157Gd NCIs, the detector materials which resulted in the highest RTF were cadmium-shielded CdTe and boron-shielded LSO, respectively. The optimal irradiation period for both carbon and helium ions was 1 µs for the 10B NCI and 1 ms for the 157Gd NCI.


Author(s):  
Eric Mauerhofer ◽  
Zeljko Ilic ◽  
Christian Stieghorst ◽  
Zsolt Révay ◽  
Matthias Rossbach ◽  
...  

AbstractThe emission of prompt and delayed gamma rays from (n,γ) and (n,n´γ) reactions induced by irradiation of indium with epithermal and fast neutrons was investigated with the instrument FaNGaS operated at Heinz-Maier-Leibnitz Zentrum (MLZ) in Garching. The average neutron energy of the neutron spectrum was 2.30 MeV. The measurement was done at an angle of 90° between neutron beam and detector. A total of 136 prompt gamma lines from which 42 are related to the capture of epithermal and fast neutrons and 94 to the inelastic scattering of fast neutrons were detected together with the delayed gamma lines of the activation products 113mIn, 114m2In, 115mIn, 116m2In and 116mIn. Intensities and neutron spectrum averaged isotopic partial cross section of the gamma lines are presented. Additionally the neutron spectrum averaged cross sections of the reactions, 113In(n,n´)113mIn, 113In(n,γ)114m2In, 115In(n,n´)15mIn, 115In(n, γ)116m2In and 115In(n, γ)116mIn were determined from the corresponding delayed gamma rays of the formed isotopes as 143 ± 22, 288 ± 13 194 ± 18, 201 ± 10 and 508 ± 24 mb respectively. The various results obtained were found consistent with the literature data. However, our measurement indicate the need to reevaluate the cross section of the 115In(n,γ)116m2In reaction for thermal neutrons.


PAMM ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Carlos A. Barajas ◽  
Gerson C. Kroiz ◽  
Matthias K. Gobbert ◽  
Jerimy C. Polf

Radiation ◽  
2021 ◽  
Vol 1 (4) ◽  
pp. 305-316
Author(s):  
Sébastien Penninckx ◽  
Félicien Hespeels ◽  
Julien Smeets ◽  
Julien L. Colaux ◽  
Stéphane Lucas ◽  
...  

In clinical practice, dose delivery in proton therapy treatment is affected by uncertainties related to the range of the beam in the patient, which requires medical physicists to introduce safety margins on the penetration depth of the beam. Although this ensures an irradiation of the entire clinical target volume with the prescribed dose, these safety margins also lead to the exposure of nearby healthy tissues and a subsequent risk of side effects. Therefore, non-invasive techniques that allow for margin reduction through online monitoring of prompt gammas emitted along the proton tracks in the patient are currently under development. This study provides the proof-of-concept of metal-based nanoparticles, injected into the tumor, as a prompt gamma enhancer, helping in the beam range verification. It identifies the limitations of this application, suggesting a low feasibility in a realistic clinical scenario but opens some avenues for improvement.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Raj Kumar Parajuli ◽  
Makoto Sakai ◽  
Kazuo Arakawa ◽  
Yoshiki Kubota ◽  
Nobuteru Kubo ◽  
...  

AbstractCarbon ion radiotherapy is a sophisticated radiation treatment modality because of its superiority in achieving precise dosage distribution and high biological effectiveness. However, there exist beam range uncertainties that affect treatment efficiency. This problem can be resolved if the clinical beam could be monitored precisely in real-time, such as by imaging the prompt gamma emission from the target. In this study, we performed real-time detection and imaging of 718 keV prompt gamma emissions using a Si/CdTe Compton camera. We conducted experiments on graphite phantoms using clinical carbon ion beams of 290 MeV/u energy. Compton images were reconstructed using simple back-projection methods from the energy events of 718 keV prompt gamma emissions. The peak intensity position in reconstructed 718 keV prompt gamma images was few millimeters below the Bragg peak position. Moreover, the dual- and triple-energy window images for all positions of phantoms were not affected by scattered gammas, and their peak intensity positions were approximately similar to those observed in the reconstructed 718 keV prompt gamma images. In conclusion, the findings of the current study demonstrate the feasibility of using our Compton camera for real-time beam monitoring of carbon ion beams under clinical beam intensity.


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