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Principles of a method to use CVD diamond detectors for spectrometric measurements of particles in mixed radiation field emitted by D-D and D-T fusion plasmas
No full textFuture thermonuclear reactors for needs of power plants will operate with the deuterium-tritium fuel. Neutron, alpha particle, and energy are created in the fusion reaction between these isotopes. Measurement of energy of the reaction products is important to control energetic balance in the thermonuclear plasma. Fast neutrons (14 MeV) should deliver energy outside the tokamak. Alpha particles are the ash of the reaction but they should also leave their energy (3.6 MeV) in the plasma to maintain the fusion reaction. Therefore, knowledge of the energy of alpha particles escaping from plasma (the lost alpha particles) is essential. Because of a short range of alpha particles the measurement has to be performed inside the tokamak, in harsh surrounding (high temperature and high particle fluxes). Diamond seems to be a proper material for use it as a semiconductor detector under those conditions. A diamond detector (synthetic high purity CVD monocrystal) was tested in aspect of its potential application for spectrometric diagnostic of the ions in tokamaks. The energy calibration of the diamond detectors of the different thickness was performed using isotopic sources: energies around 5 MeV from the 239Pu + 241Am + 244Cm source, and 6.8 and 8.7 MeV from the 212Bi + 212Po source. Additionally, monoenergetic ions beams (alpha particles and protons) were obtained from a van de Graaff accelerator in the 0.4 – 2 MeV energy range. A very good linearity of the amplitude signal vs. energy was obtained. At any working tokamak, a mixed radiation field is present consisting of various particles, like n, α, γ, p, d, t. Their contributions fluctuate depending on a regime of tokamak work and on plasma instabilities. Thus, the CVD diamond detector response in a mixed radiation field can be properly studied only in well-defined conditions of a laboratory experiment. Detection of ions and neutrons was performed at our 14 MeV neutron generator, IGN-14, where (i) the same nuclear reaction as in the D-T plasma occurs and (ii) also other types of radiation similar as at tokamaks are observed (owing to a number of different reactions on the generator target). A new measuring chamber at IGN-14 was designed and built to make possible observation of responses of detectors placed symmetrically or at different angles in respect to the primary ion beam. Two identical or different type detectors can be compared at the same time. A complex spectrograms were obtained and analysed to distinguish signals from various particles.The work has been performed within the framework of the research grant of the Polish Ministry of Science and Higher Education (MNiSW) No. NN 505 485840
Badanie wpływu parametrów meteorologicznych na czasowe charakterystyki stężenia wybranych związków chlorowcowych (CFCs) w powietrzu Krakowa w latach 1997-2012
No full textCelem niniejszej rozprawy doktorskiej jest analiza charakterystyk czasowych stężenia związków CFCs takich jak F-11 (CCl3F), F-12 (CCl2F2), F-113 (CCl2FCClF2), chloroform (CHCl3), metylochloroform (CH3CCl3), czterochlorek węgla (CCl4) i sześciofluorek siarki (SF6) w atmosferze Polski południowej. Badania objęły głównie środowisko podlegające dużej antropopresji w zakresie emisji tych związków tzn. obszar Krakowa. W tym celu konieczna była kontynuacja ciągłych pomiarów związków CFCs i SF6 rozpoczętych w 1997 r. i prowadzonych w Zakładzie Fizykochemii Ekosystemów Polskiej Akademii Nauk w okresie realizacji pracy w latach 2008 - 2012.
W ramach pracy przeprowadzono także korelacje zmian charakterystyk czasowych związków CFCs i SF6 mierzonych w Krakowie z kierunkami napływu mas powietrza na podstawie klasyfikacji sytuacji synoptycznych dla dorzecza górnej Wisły według Tadeusza Niedźwiedzia. Wymagało to opracowania metody filtracji i klasyfikacji danych w oparciu o metodę regresji ważonej dla danych pomiarowych związków CFCs i SF6 otrzymanych w Krakowie przy użyciu chromatograficznego układu pomiarowego. Podjęto również próbę użycia modelu HYSPLIT trajektorii wstecznych do wizualizacji i korelacji znaczących epizodów przekroczeń tła z napływającymi nad obszar Krakowa masami powietrza. Oprócz analizy zmieniającego się w czasie stężenia związków CFCs i SF6 w atmosferze Polski południowej, w ramach pracy dokonano porównania pomiarów stężenia tych związków w Krakowie z pomiarami prowadzanymi na stacji Mace Head w Irlandii, uczestniczącej w światowym programie AGAGE. Do tego celu użyto wyselekcjonowanych metodą regresji ważonej średnich dobowych i rocznych krakowskiej stacji pomiarowej oraz odpowiadające im wyniki oznaczeń na stacji Mace Head. Wyznaczono także roczne narosty stężenia (tzw. „growth rates”) obu placówek badawczych, przy użyciu dwóch podejść tj. metody różnicy oraz przy pomocy procedury CCGvu 4.40 rekomendowanej przez NOAA/CMDL. Na podstawie uzyskanych w ten sposób wyników dopasowano tendencje rocznych zmian atmosferycznego stężenia poszczególnych związków CFCs i SF6 w Krakowie i na Mace Head.Zintegrowany Program Operacyjny Rozwoju Regionalnego (ZPORR) 2004-2006
Narodowe Centrum Nauki DEC-2011/01/N/ST10/0762115
Technical design and operation tests of the DET-12 device for detection of delayed neutrons
No full textA technical design of the device for detection of delayed neutrons emitted from neutron-activated fissionable material samples has been performed according to physical assumptions which were earlier elaborated. The DET-12 device was constructed. The detection system was composed, consisting of twelve 3He neutron detectors, related electronics lines, and the data acquisition and recording system. The detectors were adjusted to work in groups by three connected to one preamplifier, considering a weak intensity of emission of the delayed neutrons. Laboratory measurement tests of the device operation were made with use of an isotopic neutron source. A total efficiency of neutron detection in DET-12 was experimentally determined and a relative benchmark calculation was made by means of a Monte Carlo modelling of the neutron transport in the device from the source to detectors.The work has been partly performed within the framework of the strategic research project “Technologies supporting development of safe nuclear power engineering” financed by the National Centre for Research and Development (NCBiR). Research task „Research and development of techniques for the controlled thermonuclear fusion”, Contract No. SP/J/2/143234/11
Badania osadów z wodomierzy Miejskiego Przedsiębiorstwa Wodociągów i Kanalizacji w Krakowie
No full textIn the frame of cooperation with the Municipal Water Supply and Sewage in Krakow the preliminary studies of sediments from water meters of Krakow water supply system were performed. Sediments deposited on the measuring devices installed in the water supply system, are a major technological problem and the need to replace faulty water meters is a measurable economic problem for water utilities. Chemical and phase composition investigations were carried out using proton-induced X-ray emission, energy dispersive spectroscopy, X-ray diffraction and Fourier transform infrared spectroscopy. Additionally, basing on Mössbauer spectroscopy magnetic phases were analyzed. The morphology of the chosen samples was observed on scanning electron microscopy. Mentioned methods revealed presence of amorphous and finely crystalline phases with fractions several times larger than identified crystalline one. In the crystalline phase the most frequently appeared: goethite α-FeOOH, lepidocrocite ɤ-FeOOH, and in smaller amounts: maghemite ɤ-Fe2O3, calcium carbonate CaCO3 and quartz SiO2 as well non-stoichiometric iron sulfides. In many samples nanocrystalline phase was found which due to comparative analysis, was identified as an iron hydroxide ferrihydrite with formula similar to Fe5HO8 4H2O. Moreover, presence of hematite α-Fe2O3 and akaganeite β-FeOOH phases was revealed. In several samples appearance of organic compounds were proven.Praca została wykonana w ramach współpracy między Instytutem Fizyki Jądrowej im. H. Niewodniczańskiego Polskiej Akademii Nauk a Miejskim Przedsiębiorstwem Wodociągów i Kanalizacji Spółka Akcyjna w Krakowie. Badania częściowo sfinansowano z projektu NCN 2012/05/B/ST4/01150
Badanie tendencji zmian stężeń związków chlorowcowych typu CFCs w atmosferze Polski południowej
No full textHalogenated compounds (chlorofluorocarbons-CFCs), both natural and industrial, so-called freons, currently exist as trace gases in the entire human environment. The CFCs cause ozone depletion in the stratosphere. Moreover CFCs and SF6 take part in intensification of the greenhouse effect. On account of international agreements, the measurements of CFCs and SF6 in air were started. Measurement “clean” stations were situated at places outside of urban areas influence and gathered on world program – AGAGE (Advanced Global Atmospheric Gases Experiment). One of these stations is Mace Head (Ireland, 53oN, 10oW), which participates in AGAGE since 1987 [Prinn R.G. et al., 2000] and in European InGOS (Integrated non-CO2 Greenhouse gas Observing System) program since 2011. Similar research is also conducted in Central Europe, in urban area of Krakow (Poland, 50oN, 19oE) since 1997 [Śliwka I., et al., 2010].Praca przygotowana w ramach projektów „Małopolskie Stypendium Doktoranckie” finansowane ze Zintegrowanego Programu Operacyjnego Rozwoju Regionalnego (ZPORR) 2004-2006
„Badanie tendencji zmian stężeń związków chlorowcowych typu CFCs w atmosferze Polski południowej” finansowane przez Narodowe Centrum Nauki decyzją nr. DEC-2011/01/N/ST10/0762
Ilościowe charakterystyki złożoności języka naturalnego
No full textThis doctoral dissertation includes the following main theses:
- As samples of natural language, literary texts show several properties of complex
systems: they have internal organization, including a hierarchical structure, and the interactions between their components such as words are of complicated nature, which among others can be a consequence of imposed rules of grammar and an author’s style of writing. One also observes formation of large-scale effects that are inexplicable on a basis of the sole knowledge of the individual words. Such effect can include content, emotional charge, and
artistic value of the text.
- Interactions between words defined by their mutual adjacency, after expressing them in the network representation, show certain features of networks with accelerated growth and, approximately, scale-free degree distribution of nodes. Such networks are also characterized by unique tendency to condensation, which leads to shortening of the path lengths between nodes if the number of nodes increases.
- Despite strong differences in grammar, different European languages do not show comparable differences in network topology. Substantially larger differences can be seen within one language, when one compares texts that represent different literary genres.
- Modelling of the empirical word adjacency networks is possible either directly, via the appropriate network models (e.g., by various kinds of the networks with accelerated growth), or indirectly, via network representation of the relevant stochastic processes. Comparing topology of the model networks with the empirical ones shows, however, that language has some subtleties, which cannot fully be expressed by relatively simple, generic models.
- Literary texts, if parameterized by sentence lengths and expressed in a form of time series, show clear fractal structure, and in some cases even the multifractal structure. On the literary science ground, the latter group of texts can be linked with a narrative technique called the stream of consciousness. This dissertation is divided into 5 chapters. Chapter 1 contains a short introduction with listed the main objectives and theses of the work. Chapter 2 is devoted to description of the phenomenon of natural language - its origins, evolution, and morphology. The main theories of the language origin and formal classification of languages is also discussed in this part of the work. Chapter 3 contains an introduction to complex systems science. It begins with the explanation, why physics is a branch of science the best equipped to examine such systems and the natural language in particular. Later on, the term of complexity is introduced and the most important properties of complex systems are discussed together with the methodology allowing
for their study.
Chapter 4 is a container that includes description of all the analyses and discussion
of the obtained results. It is composed of several sections devoted to specific issues. Section 4.1 presents a statistical analysis of empirical data consisting of vocabulary of six European languages with particular emphasis put on the Zipf approach. In Section 4.2 literary texts expressed by word adjacencies are a subject to network analysis. Of interest are the topological properties of these networks, especially the node connectivity distributions and the average shortest path lengths. Empirical results are confronted with the results of simulations according to different network models. Last Section 4.3 presents the results of the fractal analysis applied to time series of sentence lengths with the main stress put on identification of multifractal properties. Finally, Chapter 5 contains a summary with critical discussion of the results presented throughout this work, as well as an indication of possible directions of future research.13
Exclusive reactions with light mesons: From low to high energies
No full textIn this Thesis, a theoretical analysis of exclusive production of mesons for various reactions in nucleon-nucleon collisions is presented. Detailed studies of the central exclusive production of the resonance states and the light dimeson pairs (π+π−, K+K−) within the Regge-based framework aswell as the exclusive production of forward neutral particles has been performed in a broad range of collision energy. Different aspects of production mechanism for the considered processes have been discussed, such as the model of soft pomeron, the absorption corrections, the off-shell effects of exchanged mesons. The cross section and many differential distributions were calculated and compared with existing experimental data wherever possible. Predictions for experiments at PANDA, RHIC, Tevatron and LHC energies have been presented. In addition, diffractive and electromagnetic production of the diboson pairs (γγ, W+W−, ZZ) at high energies has been considered in the framework of kt-factorization approach with the formalism of unintegrated gluon distribution functions. The production of technipions in dominant photonphoton channel as complementary possibility of search of particles beyond the Standard Modelat the LHC has been studied.28
The optical alignment system for luminosity detector at ILC
No full textThe possibility to use semi-transparent silicon detectors to measure the displacement detector luminosity LumiCal, planned for the future linear accelerator ILC / CLIC, was studied using an optical laser system based on these detectors. Preliminary results of measurements were achieved using the prototype of this system provided in the displacement measurement values of the X and Y directions with an accuracy of a few microns
Physical assumptions for a design of the DET-12 chamber for detection of delayed neutrons
No full textPhysical assumptions have been outlined to design a new device (DET-12) for measurements of delayed neutron emitted from samples of fissionable materials activated with neutrons at big fusion-plasma devices. The aim is to support in this way a classic neutron activation method used as one of the hot plasma diagnostics at tokamaks or stellarators. Physical fundamentals of generation of the delayed neutrons are mentioned and a resulting concept of the measuring chamber is presented. A general size and dimensions of particular constituent material layers, and a number and placement of neutron detectors are optimized by means of Monte Carlo modelling of the neutron transport. Recommendations for a technical design of the measuring chamber are formulated.The work has been partly performed within the framework of the strategic research project “Technologies supporting development of safe nuclear power engineering” financed by the National Centre for Research and Development (NCBiR). Research task „Research and development of techniques for the controlled thermonuclear fusion”, Contract No. SP/J/2/143234/11
Upgrade of the equipment for production of gallium isotopes from proton - activated zinc targets
No full textTwo gallium isotopes, 66Ga (T1/2=9.4h, β+ 4.2MeV) and 67Ga (T1/2=78h, EC), can serve as good models in development of new 68Ga-labelled (T1/2=68m, β+ 1.9MeV) PET radiopharmaceuticals. In order to produce 66Ga and/or 67Ga from zinc targets activated in a medical cyclotron, we designed a prototype target whose external dimensions match the geometry of other standard targets, but which contains modified internal parts. Besides, we equipped our old apparatus for solvent extraction of 67Ga in new, remotely controlled, electric valves. Performance of the upgraded chemical apparatus turned out good and the gas- and water-tightness of the new target at room temperature were satisfactory too. Performance of the new target in the transport lines of the PETtrace cyclotron as well as its behavior in harsh thermal conditions have to be the matter of future experiments