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The IBA self-extracting cyclotron project

100%

Kleeven W. , Lucas S. , Delvaux J. , Swoboda F. , Zaremba S. , Beeckman W. , Vandeplassche D. , Abs M.

tom Vol. 48,suppl.2

59-67

The self-extracting cyclotron is a high-intensity 14 MeV H+ machine for isotope production. There is no electrostatic deflector. Extraction is achieved with a special shaping of the magnetic field. There are two long poles and two short poles, both with an elliptical gap profile; this provides a steep fall off of the magnetic field at the pole radii. An extraction groove is machined in the iron of one of the longer poles. First harmonic coils create a large orbit separation at the entrance of the extraction path and extract the beam. The machine is presently installed in the industrial isotope production site where the final commissioning and tests took place. Beams of more than 1.5 mA have been extracted and transported. Further development is ongoing in order to increase the current on target to at least 2 mA in the coming months. Commercial isotope production will start in the course of this year. The concept of the machine is explained and the layout of the machine and beam lines is presented. Results of orbit calculations and central region optimizations are given. Results of the measurement of extracted beam shapes and emittances are given. The progress and present status of the project are discussed.

Status report of the VINCY Cyclotron

88%

Nešković N. , Ristić-Ðurović J. , Vorojtsov S. B. , Belicev P. , Ivanenko I. A. , Ćirković S. , Vorozhtsov A. S. , Bojović B. , Dobrosavljević A. , Vujović V. , Comor J. j. , Pajović S. B.

tom Vol. 48,suppl.2

135-139

The VINCY Cyclotron is the main part of the TESLA Accelerator Installation. The diameter of the pole of this machine is 2000 mm. Its bending constant is 145 MeV while its focusing constant is 75 MeV. The radiofrequency system of the machine consists of two l/4-resonators with the eigenfrequency in the range from 17 to 31 MHz. Ions coming from a heavy ion source or a light ion source will be injected into the machine axially. They will be introduced into its median plane by a spiral inflector. Heavy ions accelerated in the machine will be extracted from it by a foil stripping system or by an electrostatic deflection system. Light ions will be extracted from it by the foil stripping system. The first programs of use of the VINCY Cyclotron are related to routine and experimental production of radioisotopes and radiopharmaceuticals, and to biomedical research with ion beams. The first beam extracted from the machine will be the proton beam of the energy of 22 MeV obtained from the H2+ beam extracted from the light ion source. This beam will be used first for production of radioisotope 18F and radio-pharmaceutical 18FDG, to be employed for positron emission tomography

Izotopy promieniotwórcze w osadach dennych antropogenicznego zbiornika wodnego w Pławniowicach [komunikat]

75%

Tuszyński M. , Kostecki M.

tom Vol. 29, no. 1

134--140

Przedstawiono koncentracje izotopów promieniotwórczych w osadach dennych antropogenicznego zbiornika wodnego w Pławniowicach (gmina Rudziniec, województwo śląskie). Próby osadów pobrano z dwunastu stanowisk wzdłuż długiej i krótkiej osi zbiornika. Pomiary przeprowadzono techniką wysokoczułej spektrometrii promieniowania gamma z detektorem półprzewodnikowym typu HPGe. Stwierdzono występowanie: izotopów promieniotwórczych z szeregu uranowo-radowego, szeregu torowego, naturalnego izotopu potasu 40K oraz sztucznego izotopu cezu 137Cs. Średnia koncentracja zidentyfikowanych izotopów wynosiła 40K-347Bq/kg, 137Cs-205 Bq/kg, rodziny 238U-45 Bq/kg, rodziny 232Th-24 Bq/kg. Stwierdzono, że koncentracje wykrytych izotopów sa na poziomie normalnie spotykanym w środowisku naturalnym i w żadnym punkcie nie odbiegały od wartości przeciętnie spotykanych. Koncentracje te nie stanowią żadnego zagrożenia radioaktywnego.

The distribution of radioactive substances in cores collected in l2 sample points of bottom sediments of Pławniowice antropogenic water reservoir has been studied. This ecosystem is an artificial reservoir on the Potok Toszecki river, which goes through the agricultural region in the west part of the Upper Silesian region. The aim of the work was to investigate samples from bottom sediments to determine sort and amount of radionuclides and other chemical elements and biological substances. These samples were taken from eleven points along the short and long axis of reservoir and were divided from 10-cm layers of bottom sediments. The measurement of radioactivity substances using high sensitive gamma spectrometry technique with semiconductor detector HPGe type was done. There was shown occurrence of radionuclides from uranium-radium 238U progeny, thorium 232Th progeny, the natural radionuclide of potassium 40K and the artificial radioisotope of cesium 137Cs. The mean activity concentration of radioelements is 40K - 347,0 Bq/kg, 137Cs - 204,7 Bq/kg, 238U - 44,5 Bq/kg, 232Th - 24,0 Bq/kg. Besides the concentrations change of radioisotope along the reservoir in the sediments was analyzed. A higher concentration of radioisotopes at the end of the lake was observed generally. For the cesium 137Cs the highest concentration in the 10-cm layer was in the middle points of the lake (for maximal deep) determined. This could be related with the Chernobyl accident. The concentrations of radioisotope are naturally in the environmental and are not dangerous.