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1

Verification of the use of GEANT4 and MCNPX Monte Carlo codes for calculations of the depth-dose distributions in water for the proton therapy of eye tumours

Grządziel M., Konefał A., Zipper W., Pietrzak R., Bzymek E.

Nukleonika

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2014

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Vol. 59, No. 2

61--66

EN

Verification of calculations of the depth-dose distributions in water, using GEANT4 (version of 4.9.3) and MCNPX (version of 2.7.0) Monte Carlo codes, was performed for the scatterer-phantom system used in the dosimetry measurements in the proton therapy of eye tumours. The simulated primary proton beam had the energy spectra distributed according to the Gauss distribution with the cut at energy greater than that related to the maximum of the spectrum. The energy spectra of the primary protons were chosen to get the possibly best agreement between the measured relative depth-dose distributions along the central-axis of the proton beam in a water phantom and that derived from the Monte Carlo calculations separately for the both tested codes. The local depth-dose differences between results from the calculations and the measurements were mostly less than 5% (the mean value of 2.1% and 3.6% for the MCNPX and GEANT4 calculations). In the case of the MCNPX calculations, the best fit to the experimental data was obtained for the spectrum with maximum at 60.8 MeV (more probable energy), FWHM of the spectrum of 0.4 MeV and the energy cut at 60.85 MeV whereas in the GEANT4 calculations more probable energy was 60.5 MeV, FWHM of 0.5 MeV, the energy cut at 60.7 MeV. Thus, one can say that the results obtained by means of the both considered Monte Carlo codes are similar but they are not the same. Therefore the agreement between the calculations and the measurements has to be verified before each application of the MCNPX and GEANT4 codes for the determination of the depth-dose curves for the therapeutic protons.

2

Uranium, radium and radon isotopes in selected brines of Poland

Kozłowska B., Walencik A., Przylibski T. A., Dorda J., Zipper W.

Nukleonika

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2010

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Vol. 55, No. 4

519-522

EN

Natural radioactive isotopes were studied in nine different types of brines from four locations in Poland. Investigated brines are exploited from various geological structures composed of the rocks of different chemical and mineral composition as well as different age and depth. All investigated brines are used in balneotherapy (i.e. baths, inhalations, showers). The main goal of this study was to obtain some basic knowledge on the activity range of natural elements such as uranium, radium and radon in different brine types in Poland and their variability depending on their location in certain geological structures. Activities of 234,238U, 226,228Ra and 222Rn isotopes were measured with the use of two nuclear spectrometry techniques: liquid scintillation and alpha spectrometry. The activity concentrations of 222Rn vary from below 1 to 76.1 plus or minus 3.7 Bq/l, for the 226Ra isotope from 0.19 plus or minus 0.01 to 85.5 plus or minus 0.4 Bq/l and for 228Ra from below 0.03 to 2.17 plus or minus 0.09 Bq/l. For uranium isotopes, the concentrations are in the range from below 0.5 to 5.1 plus or minus 0.4 mBq/l for 238U and from 1.6 plus or minus 0.4 to 45.6 plus or minus 2.0 mBq/l for 234U. The obtained results indicate high radium activity concentrations corresponding to high mineralization of waters.

3

Natural radioactivity of groundwater from the Przerzeczyn-Zdrój Spa

Walencik A., Kozłowska B., Przylibski T. A., Dorda J., Zipper W.

Nukleonika

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2010

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Vol. 55, No. 2

169-175

EN

The present authors performed investigations of natural radioactivity in groundwater from the Przerzeczyn- -Zdrój Spa. Some of the waters are regarded as medical and are used for balneological purposes. Samples from seven groundwater intakes were collected 5 times over a period of 8 years (1999–2007). In order to obtain necessary data, two different nuclear spectrometry techniques were applied: α spectrometry and liquid scintillation spectrometry. The activity concentrations of 222Rn varied in the range from 15±2 Bq/l to 154±22 Bq/l. The results of activity concentrations of 226,228Ra varied from below 10 mBq/l to 30±1.5 mBq/l and from below 30 mBq/l to 60±4 mBq/l, respectively. Activity concentration lower than minimum detectable activity (MDA) was obtained for 3 samples for 226Ra and 4 for 228Ra determinations out of 7 investigated samples. The uranium content in the studied samples was determined once and the value ranged from 4.5±0.6 mBq/l to 13.6±1.2 mBq/l for 238U and from 17.1±0.9 mBq/l to 52.2±2.8 mBq/l for 234U. All obtained values for uranium isotopes showed activity concentrations above MDA. The activity ratios 234U/238U, 222Rn/226Ra and 226Ra/238U and the correlations between different isotopes concentrations were evaluated.

4

Influence of the energy spectrum and spatial spread of proton beams used in eye tumor treatment on the depth-dose characteristics

Konefał A., Szaflik P., Zipper W.

Nukleonika

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2010

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Vol. 55, No. 3

313-316

EN

The influence of the energy spectrum and the spatial spread of a therapeutic proton beam impinging on an irradiated medium (called the entrance beam) on the depth-dose characteristics in water, in the proton energy range of 50 division sign 70 MeV was studied. It turns out that full width at half maximum (FWHM) of the Bragg peak increases almost linearly with increasing proton energy. It ranges from 1.53 mm for 50 MeV to 2.59 mm for 70 MeV, for monoenergetic protons. Moreover, the significant influence of the energy spread of the entrance proton beam on the intensity and FWHM of the Bragg peak is visible. FWHM of the Bragg peak of 60 MeV protons is equal to 2.03, 3.37 and 5.86 mm for a monoenergetic beam and beams with an energy spread of 0.5 and 1 MeV SD (standard deviation), respectively. The intensity of the Bragg peak of a 60 MeV proton beam with an energy spread of 1 MeV SD is approximately 25% less than that for a monoenergetic beam. Moreover, the Bragg peak shifts to smaller depths as the energy spread of the entrance beam increases. The shift of the peak is about 0.2÷0.3 mm for a beam with an energy spread of 0.5 MeV SD and between 0.4 division sign 0.5 mm for an energy spread of 1 MeV SD, compared with a monoenergetic beam in the energy range from 50 to 60 MeV. However, the spatial spread of the entrance proton beam does not affect significantly the depth-dose characteristic.

5

Thermal and epithermal neutrons in the vicinity of the Primus Siemens biomedical accelerator

Konefał A., Dybek M., Zipper W., Łobodziec W., Szczucka K.

Nukleonika

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2005

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Vol. 50, nr 2

73-81

EN

In this paper, the thermal and epithermal neutron fluence distributions in the vicinity of the Primus Siemens accelerator are presented. The measurements were carried out by the use of the neutron activation method for 15 MV X-rays and electron beams of 18 MeV and 21 MeV. From the radiation safety point of view for the hospital personnel, it is important to know the thermal and epithermal neutron fluence distribution in the vicinity of the accelerator because the neutrons interacting with atoms of a medium by various processes induce the activity of objects (accelerator, other apparatus etc.) and walls in the treatment room. The thermal and epithermal neutron capture, particularly, in high atomic number materials of the accelerator head can be a significant source of gamma radiation and it has to be taken into account for estimation of the work safety of the personnel. Values of the neutron fluence were normalized to the maximum photon (or electron) dose Dmax,gamma (e) measured at the central axis of therapeutic X-ray (or electron) beam in a water phantom. The thermal neutron fluences measured during the 15 MV X-ray emission varied between 1.1 × 10 5 n ź cm 2ź Gy -1 and 4.4 × 10 5 n ź cm -2ź Gy 1 whereas the epithermal neutron fluences ranged from 0.2 × 10 5 n ź cm 2ź Gy- 1 to 1.8 × 105 n ź cm -2ź Gy -1. In the case of electron beams, the neutron fluence measurements were performed only at the isocentre. The obtained thermal and epithermal neutron fluences were 1.2 × 10 4 n ź cm -2ź Gy -1 and 0.6 × 10 4 n ź cm -2ź Gy -1, respectively, for the 18 MeV electrons. In the the case of the 21 MeV electron beams the thermal neutron fluence was -2.0 × 10 4 n ź cm -2ź Gy -1 whereas the epithermal neutron fluence was 0.8 × 10 4 n ź cm -2ź Gy-1.

6

Kronika

Zipper W., Chałasińska-Macukow K., Szytuła A., Czerwonko J., Szymczak H., Lipkowski J., Szudy J.

Postępy Fizyki

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1999

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T. 50, z. 3

162-167

PL

PTF: Oddział Katowicki, Oddział Kielecki. Międzynarodowa Komisja Optyczna. Nagroda Wolfa za kwazikryształy. Medal Maksa Plancka. Polskie Towarzystwo Rozpraszania Neutronów. Izrael członkiem stowarzyszonym ESFR. Doktorat honoris causa Politechniki Wrocławskiej dla Mojsieja I. Kaganowa. Stypendia krajowe FNP dla najlepszych młodych badaczy. W Niemczech więcej funduszy na naukę. We Francji obcinanie budżetów wielkich urządzeń. Biografie Heisenberga i Einsteina w Internecie. Granular Matter. Siergiej W. Wonsowski (1910 - 1998). Piotr Modrak (1939 - 1999). Stanisław Mrozowski (1902 - 1999).

7

XXXIV Zjazd Fizyków Polskich w Katowicach [Ze zjazdów i konferencji]

Zipper W.

Postępy Fizyki

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1998

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T. 49, z. 2

106-109

PL

W dniach 15-18 września 1997 r. odbył się XXXIV Zjazd Fizyków Polskich. Miejscem tego kolejnego zgromadzenia fizyków polskich był Instytut Fizyki Uniwersytetu Śląskiego w Katowicach, a głównym organizatorem Polskie Towarzystwo Fizyczne - Oddział w Katowicach. Zjazd był niewątpliwie nobilitującym wydarzeniem dla całego środowiska naukowego w Katowicach. Wzięło w nim udział ok. 700 osób. Do wygłoszenia wykładów plenarnych, dających przegląd osiągnięć fizyki światowej i polskiego wkładu do niej, zaprosiliśmy wybitnych fizyków polskich. Gośćmi honorowymi Zjazdu byli czterej laureaci Nagrody Nobla: J. Georg Bednorz, Herbert A. Hauptman, Harold W. Kroto, Rudolf L. Mossbauer, a także prezes Europejskiego Towarzystwa Fizycznego Herwig Schopper, którzy poprzez swoje wykłady plenarne nadali naszemu Zjazdowi jeszcze większą rangę i znaczenie. Wszystkich wykładów plenarnych było siedemnaście. W Zjeździe uczestniczyli także przedstawiciele kilkunastu europejskich towarzystw fizycznych.

8

Determination of radium isotopes concentrations in mineral waters by liquid scintillation method

Hetman A., Dorda J., Zipper W.

Nukleonika

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1998

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Vol. 43, nr 4

481-488

EN

The method of the determination of radium isotopes (sup 226)Ra and (sup 228)Ra in the saline and mineral waters based on the LSC with the separation of α and β rays is presented. Concentrations of radium isotopes were calculated using Bateman equations for α and β components of (sup 226)Ra, (sup 228)Ra, without waiting for the radioactive equilibrium. The concentrations of these isotopes are very low in most mineral waters found in the market with the exception of two waters where the concentration of long life isotope (sup 226)Ra is high. Therefore, it is necessary to investigate the radium isotopes concentration in drinking mineral waters.

PL

Przedstawiono metodę oznaczania izotopów radu w zasolonych i mineralnych wodach, bazując na możliwości separacji widma alfa/beta na detektorze ciekłoscyntylacyjnym. Stężenia oznaczanych izotopów wyznaczano analitycznie, nie wyczekując osiągnięcia odpowiednich stanów równowagi promieniotwórczej. Analizę oparto na równaniach Batemana dla składowych alfa i beta (sup 226)Ra i (sup 228)Ra oraz odpowiednich procedurach obliczeniowych. Wykorzystując tę metodę przebadano wybrane, powszechnie dostępne wody mineralne, butelkowe. W większości wód stężenia tych izotopów są zdecydowanie niskie. Natomiast na szczególną uwagę zasługują wody z okolic Polanicy Zdroju, w których stężenie długożyciowego izotopu radu (sup 226)Ra jest wysokie (przy nieobecności izotopu (sup 228)Ra). Z punktu widzenia ochrony radiologicznej konieczne staje się badanie wód mineralnych na obecność izotopów radu.