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1

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

Application of alanine dosimetry in dose assessment for ocular melanoma patients undergoing proton radiotherapy : preliminary results

Mierzwińska G., Kłodowska M., Michalec B., Pędracka A., Rydygier M., Swakoń J., Waligórski M. P. R.

Nukleonika

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2015

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Vol. 60, No. 3, part 2

609--613

EN

Basing on alanine solid state/electron paramagnetic resonance (EPR) dosimetry, a supplementary method of cumulatively recording the therapeutic dose received by ocular cancer patients undergoing fractionated proton radiotherapy is proposed. By applying alanine dosimetry during the delivery of consecutive fractions, the dose received within each fraction can be read out by EPR spectrometry and a fi nal permanent cumulative record of the total dose delivered obtained. The dose response of the alanine detector was found to be practically independent on its position within the extended proton Bragg peak region. Dose measurements based on entrance dose recorded in proton beams individually formed for each patient are presented. The described method will be applied as a complementary Quality Assurance procedure for patients undergoing proton radiotherapy at the Institute of Nuclear Physics, Polish Academy of Sciences, Krakow, Poland (IFJ PAN).

3

Jonoluminescencja SiC wzbudzana bombardowaniem jonami H+

Pyszniak K., Żuk J., Droździel A., Wójtowicz A., Prucnal S., Turek M.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 5

281-283

PL

Zaprezentowano wyniki badań jonoluminescencji węglika krzemu bombardowanego jonami H+ o energiach 120 i 180 keV. Widma jonoluminescencji w zakresie 400-800 nm mają charakter ciągły z maksimum odpowiadającym fali o długości 730 nm. Badano także zmiany natężenia świecenia wywołane bombardowaniem jonowym. Zaobserwowano bardzo szybkie (dwa rzędy wielkości) osłabienie świecenia (dawki rzędu 4·1014 H+/cm2) wywołane zwiększającą się ilością defektów w tarczy. Artykuł zawiera także prezentację aparatury pomiarowej.

EN

Experimental results of the silicon carbide ionoluminescence induced by 120 and 180 keV H+ ion beams. The obtained spectra in the range 400-800 nm are continuous with the maximum at approximately 730 nm. Changes of the luminescence intensity caused by accumulated irradiation fluence were also studied. A very fast decrease of luminescence intensity (by two orders of magnitude) for a relatively small fluence (4·1014 H+/cm2) due to the increasing damage ot the target was observed. A brief description of experimental set-up is also given.

4

Dosimetric characteristics of active solid state detectors in a 60 MeV proton radiotherapy beam

Sowa U., Nowak T., Michalec B., Mierzwińska G., Swakoń J., Olko P.

Nukleonika

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2012

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Vol. 57, No. 4

491-495

EN

Several solid state detectors, such as dosimetric diodes, MOSFET detectors or diamond detectors are used for quality control of radiotherapy beams. The goal of this work was to determine dosimetric properties of the PTW diamond detector (DD) and the PTW silicon diode in the 60 MeV therapeutic beam (practical range in water Rp = 29.17 mm) located at the Institute of Nuclear Physics, Polish Academy of Sciences (IFJ PAN, Kraków). A PTW Markus ionization chamber was used as a reference device. The empirical correction factor for diamond detector, kDD(Rresidual), introduced in the Technical Report Series of IAEA, TRS-398 [9] as a function of beam quality, Rresidual, was found to decrease from 1.12 for Rresidual = 1.5 mm to 1.04 for Rresidual = 26 mm. The reproducibility of response of DD and PTW diodes in the proton filed did not exceed 0.11%. Our results show that diamond detectors and dosimetric diodes are useful tools for quality assurance (QA) of therapeutic proton beam, but each type of detectors has specific properties which should be taken into account when choosing particular application.

5

Alanine dosimetry of 60 MeV proton beam - preliminary results

Michalec B., Mierzwińska G., Sowa U., Ptaszkiewicz M., Nowak T., Swakoń J.

Nukleonika

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2012

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Vol. 57, No. 4

503-506

EN

Electron paramagnetic resonance (EPR) spectrometry (X-band) was used to determine the dose absorbed in alanine detectors, of different shapes and different alanine content, irradiated with Co-60 gamma rays and in a 60 MeV proton beam. The goal of our study was to confirm applicability of alanine as a passive detector in therapeutic proton beam. In the paper dose response characteristic and relative efficiency of alanine are shown. The study confirmed that alanine detectors with a high alanine content (ca. 95%) may be a useful and convenient tool for dose measurements in proton beams, used for eye cancer treatment.

6

Komora rekombinacyjna do dozymetrii terapeutycznych wiązek protonów

Krzemiński Ł.

Elektronika : konstrukcje, technologie, zastosowania

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2010

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Vol. 51, nr 7

231-233

PL

Artykuł prezentuje konstrukcje specjalnej komory rekombinacyjnej, oznaczonej jako F4 i przeznaczonej do pomiarów dozymetrycznych na stanowiskach do terapii protonowej. Komora może być użyta w wiązkach akceleratorów protonów i ciężkich jonów przy bardzo dużych dawkach.

EN

The paper presents the design of special recombination chamber denoted as F4 and dedicated for dosimetric measurements at proton radiotherapy facilities. The chamber can be used in the beams of protons and heavy ions, at high dose rates.

7

AIC-144 cyclotron: present status

Bakewicz E., Budzanowski A., Taraszkiewicz R.

Nukleonika

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2003

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Vol. 48,suppl.2

117-121

EN

The presented AIC-144 cyclotron was designed and constructed 20 years ago in the Institute of Nuclear Physics in Kraków (Poland). Later on it was modernized, after the decision of creating the Hadron Radiotherapy Centre in Kraków was taken by the government. At present, the cyclotron is capable to deliver beams of protons (with energy up to 60 MeV), deuterons (with energy up to 30 MeV) and a-particles (with energy up to 60 MeV). The magnetic structure and the RF system were modernized (a new HF generator with output power 120 kW and frequency range 10-27 MHz was installed; an RF cavity resonator was reconstructed to improve the Q-factor at the highest frequencies). The new PIG source and system of central diaphragms was built to improve beams quality on the first turns. The single lamella and multilamella probes were fully reconstructed. Special effort was put on a highly efficient extraction system. The precession method for particles extraction was chosen as the best one. All computer simulations and experimental runs were done in close cooperation with specialists from the Laboratory of Nuclear Problems JINR, Dubna. The extraction system consists of 2 electrostatic deflectors, 3 magnetic channels (passive) and 4 coils for shaping of the 1st harmonic. So far, the beam extraction experiments were carried out for the proton beams with the final energy of 35 MeV, 48 MeV and 60 MeV. For all these energies the efficiency of extraction was above 50%. A computer remote control of the main magnet power supply and of the 24 correction coils was installed and put into operation. In the last 3 years, the internal beams of protons and a-particles were used to produce radioisotopes like 11C, 57Co, 83-85Sr, 102Rh, 111In, 173-175Hf, 178-181W.

8

Diagnostic of intense proton beams by hydroacoustic means

Albul V. I., Bychkov V. B., Gusev K. B., Demidov V. S., Demidova E. V., Kurchanov A. F., Lukijashin V. B., Vasilijev S. S.

Hydroacoustics

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2003

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Vol. 6

293--294

EN

Detecting and parameters' measurement of intense beams of charged particles in accelerators' laboratories is possible to make in water volumes, using conventional measuring hydrophones with applying of new means and algorithms of hydroacoustic signals' processing. The new experimental results is given and discussed.

9

A new extraction system for the upgraded AIC-144 cyclotron

Bakewicz E., Daniel K., Doruch H., Sulikowski J., Taraszkiewicz R., Morozov N., Samsonov E., Shakun N., Vorojtsov S.

Nukleonika

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2001

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Vol. 46, nr 2

51-57

EN

This paper is a description of the computer simulation and the first experimental results on an AIC-144 isochronous cyclotron new extraction system. The cyclotron will be able to generate beams of protons, deuterons and alfa particles. One of the principal goals of the upgraded facility is to extract beams of protons and deuterons (proton energy 60 MeV, deuteron energy 30 MeV) for proton radiotherapy and for fast neutron beams. The precession method for particle extraction was chosen as the best one. It is the first time that the proton beam of energy 35 MeV has been extracted from the AIC-144 cyclotron with an efficiency of above 50%. More careful adjustment of the extraction system parameters (better control of the 1st harmonic of the magnetic field and the position of the deflectors) will permit an increase in the extraction efficiency to the design value of 70%.