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Cross-sections and gamma-yields in (p, x) reactions on 14N and 16O for 14,15O production

Kadenko Ihor, Sakhno Nadiia V., Moskal Pawel

Bio-Algorithms and Med-Systems

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2023

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Vol. 19, no. 1

139--143

EN

Dose delivery in proton beam therapy requires significant effort for in vivo verification. PET is considered as one of the most precise methods for such verification using short- -lived radionuclides. One of the newer approaches in proton therapy is based on FLASH therapy, when a 40-60 Gy absorbed dose could be delivered in millisecond time intervals. For this very promising type of therapy a very important task is to reliably identify the beam stopping position within the corresponding organ with a tumor in the patient’s body. This could be done if the beam proton energy in the body is still above the threshold of the corresponding nuclear reaction, in the outgoing channel of which will be produced positron-emitting nuclei. In this work we consider the production of oxygen radionuclides emitting positrons 14O (the half-life 70.6 s) and 15O (the half-life 122.2 s). Using the TALYS code, we calculated cross sections of proton-induced nuclear reactions on 14N and 16O, leading to the formation of 14,15O with the application of a well- -working optical model. In addition, we calculated total gamma-production and average gamma-emission energy for incident proton energy 150 MeV.

2

Aparatura do zderzeń wiązek jonowych z gazowymi tarczami

Pranszke B.

Zeszyty Naukowe Akademii Morskiej w Gdyni

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2015

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nr 91

142--148

PL

W artykule opisano aparaturę przeznaczoną do badań zderzeniowych procesów z udziałem tzw. gorących atomów (występujących w przestrzeni kosmicznej i mogących w istotnej skali oddziaływać z materiałami powłok znajdujących się tam obiektów technicznych). Przedstawiono wybrane wyniki badań. W szczególności skupiono się na oddziaływaniu wiatru gwiazdowego z drobinami, wchodzącymi w skład atmosfer planetarnych oraz gęstych obłoków materii międzygwiazdowej.

EN

At present, they continued research related to the stellar wind interaction with gases belonging to the ISM (interstellar medium). These studies, together with the already published results contribute to a better understanding of the fundamental processes in planetary atmospheres and space. The obtained optical spectra will enable a deeper analysis of the data collected by the telescopes Hubble, FUSE, UVES. This paper describes an apparatus designed for study of collisional processes involving the so-called hot atoms (occurring in space and could have a significant role in interactions with coatings materials found there technical objects). Selected results are presented. In particular, it focuses on the interaction of the stellar wind with particles forming the planetary atmospheres and interstellar medium.

3

Properties and Structure of Polish Alpaca Wool

Czaplicki Z.

Fibres & Textiles in Eastern Europe

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2012

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Vol. 20, no. 1 (90)

8-12

PL

W artykule przedstawiono strukturę i najważniejsze parametry wełny z alpak hodowanych w Polsce. Na podstawie badań mikroskopowych powierzchni włókien i przekrojów poprzecznych pokazano budowę zewnętrzną i wewnętrzną. Stwierdzono, iż zarówno powierzchnie jak i przekroje poprzeczne włókien wełny alpaki wykazują różnice w stosunku do włókien wełny owczej. Najważniejszy parametr jakim jest średnica włókna mierzono 3 metodami, w tym metodą laserową (Laser-Scan). Do badań pobrano 15 prób pochodzących z alpak ze stada liczącego 120 sztuk. Stwierdzono pewne zróżnicowanie wyników badań średnic włókien w zależności od metody badawczej. Analiza korelacji wykazała, że największa zgodność wyników średnic wełen alpaki występuje dla metody przy użyciu mikroskopu skaningowego (SEM) i aparatu Laser-Scan. Duże różnice w zmienności grubości włókien dla poszczególnych prób świadczą o niejednorodności wełny w całym stadzie alpak. Stwierdzenie to wskazuje na niekontrolowany rozwój hodowli alpak.

EN

This paper reports on the structure and most significant parameters of wool from alpacas bred in Poland. The external and internal structures of the fibre were evaluated based on microscopic observations of the fibre surface and cross sections. It was determined that both the surfaces and cross sections of the alpaca fibres show differences when compared to wool fibres. The diameter, which is the most important fibre parameter, was measured using three methods (including the Laser-Scan method).Investigations were made on 15 samples taken from various alpacas from a herd of 120 animals. Depending on the investigation method used, certain differences in the fibre diameter were observed. An analysis showed that the results of measurements of alpaca wool diameter best correlate when using the scanning electron microscopy and Laser-Scan methods. Large variations in the fibre thickness of the various samples prove the non-uniformity of wool from the whole alpaca herd, indicating that alpacas are bred in an uncontrolled (random) way.

4

New method of pure 111In production by proton-induced nuclear reactions with enriched 112 Sn

Betak E., Rurarz E., Mikołajewski S., Wojtkowska J.

Nukleonika

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2007

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Vol. 52, nr 1

17-27

EN

We aimed at finding out a simple and reliable way of 111In production with the highest radionuclide purity from its grand parent 111Sb and parent 111Sn nuclei, produced by the 112Sn(p,2n)111Sb and 112Sn(p,pn)111Sn reactions, respectively. The target was a metallic 112Sn sample enriched to 84%. We have measured activation cross sections for seven reactions on an enriched 112Sn sample induced by 23.6 š 0.8 MeV energy protons. Gamma-ray spectroscopy with high-purity germanium detectors has been used. We also identified the activities of 55Co (T1/2 = 17.5 h) and 60Cu (T1/2 = 23.7 min) in proton beam monitoring Ni foils, induced in the natNi(p,X)55Co and natNi(p,X)60Cu reactions at 22.8 MeV proton energy. The cross sections determined for these reactions are: s[natNi(p,X)55Co] = 36.6 š 4 mb and s[natNi(p,X)60Cu] = 64.4 š 7 mb. The measured cross sections of reactions on tin isotopes are: sigma[112Sn(p,n)112Sb] = 4 š 0.8 mb; sigma[112Sn(p,2n)111Sb] = 182 š 26 mb; sigma[112Sn(p,pn)111Sn] = 307 š 35 mb; sigma[114Sn(p,2n)113Sb] = 442 š 52 mb; s[117Sn(p,n)117Sb] = 15 š 3 mb; sigma[117Sn(p,p’gamma)117mSn] = 0.37 š 0.06 mb; s[115Sn(p,2p)114m2In] = 0.01 š 0.002 mb. Our measurements indicated the expected yield of the 111In production to be 46 MBq/mAh (1.2 mCi/mi Ah). The contamination of 111In by the undesired nuclide 114m2In was determined and belongs to the smallest ones found in the literature. The measured cross sections were compared with theoretical calculations by two top-level nuclear reaction codes EMPIRE and TALYS.