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The Standard Model Analyasis Of The Cp Violation In The Inclusive Semileptonic B-meson DecaysEygi, Zeynep Deniz 01 February 2005 (has links) (PDF)
Being a flavor changing neutral current process, inclusive semileptonic B- meson decays provide reliable testing grounds for the Standard Model at the loop level. They are also importanat in the CKM phenomology and investing the CP violation due to the existence of sizable interference terms in the decay amplitude. In this work , the rare inclusive semileptonic B- meson decays for (lepton is electron ,muon , tau) are investigated in the context of the Standard Model.The differential branching ratio, forward-backward asymmetry ,CP &ndash / violating asymmetry and CP &ndash / violating asymmetry in the forward-backward asymmetry in these processes are examined.The dependencies of these physical parameters on the Standard Model parametres are analyzed by paying a special attention to the long distance effects. Although the branching ratios predicted for the inclusive semileptonic B- meson decays are relatively small because of CKM suppression , it has been found that there is a significant ACP and ACP(AFB) for these processes.
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Model Independent Analysis Of Rare Exlusive B-meson DecaysCakmak, Kerim Mehmet 01 January 2004 (has links) (PDF)
Using the general, model indepenent form of the effective Hamiltonian, the general expressions of the longitudinal, normal and transversal polarization asymmetries for l+ and l- for the effective B -> / K(K*)l+l- decays has been calculated. Existence of regions of Wilson coefficients for which the branching ratio coincides with the Standard Model result, while the lepton polarizations differ from the standard model prediction is expected. Hence, studying lepton polarizations in these regions of Wilson coefficients may be helpful in establishing new physics beyond standard model.
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Determinacao de fatores de conversao de dose para radiacao gama externa em residenciasMADUAR, MARCELO F. 09 October 2014 (has links)
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Cs-137 i Svamp : Dataanalysrutiner för gammaspektroskopiNordman, David January 2018 (has links)
Kärnkraftsolyckan i Tjernobyl ledde till en spridning av radioaktiva ämnen över Europa och Sverige. År 2018 är det 32 år sedan kärnkraftsolyckan ägde rum och den enda radioaktiva isotopen som finns kvar i det svenska ekosystemet som följd av olyckan i en betydande mängd är Cs-137, på grund av dess 30-åriga halveringstid. Genom att bestämma aktiviteten hos svamp kan halten Cs-137 i mark uppskattas. Hösten 2018 kommer det tvärvetenskapliga massexperimentet Strålande jord att utföras i syfte att kartlägga denna halt i hela Sverige. Syftet med detta examensarbete var att nå resultat som är användbara vid aktivitetsbestämning av svamp. Ett numeriskt verktyg för analys av data ifrån gammaspektroskopi har konstruerats. Två metoder för att beräkna händelser (counts) i energitoppar i gammaemissionsspektra har formulerats och varit byggstenar för det vidare arbetet. Under arbetets gång har följande bestämts: effektiviteten hos en high purity germanium (HPGe) detektor, aktiviteten hos två svampprover, attenueringskoeffcienten av 662 keV-gamma för samma svampprover samt för vatten. För att kunna approximera en burk med svamp som en isotropt strålande punktkälla och få goda resultat behöver aktivitetsmätningarna göras med ett långt avstånd mellan provet och detektorn. Att mätningar måste göras på ett långt avstånd gör att approximationen bara är lämplig för ett svampprov med hög aktivitet, vilket blev tydligt i detta examensarbete då aktiviteten hos ett lågaktivt svampprov inte kunde bestämmas med god statistik trots att enskilda mätningar gjordes under närmare en veckas tid. Systematiska fel har inte tagits hänsyn till i detta arbete, utan enbart statistisk osäkerhet. / The nuclear disaster in Chernobyl brought radioactive substances over Europe and Sweden. In 2018 it has passed 32 years since the disaster and the only radioactive isotope that reamins in the swedish ecosystem at a signicant level is Cs-137. By determining activity of mushroom, the amount of Cs-137 in the ground can be estimated. In the fall of 2018, the interdisciplinary mass-experiment Strålande jord will take place with the purpose to map this amount all over Sweden. The purpose of this work was to reach results that could be of use when determining the activity of mushroom. A numerical tool for analysing data from gamma spectroscopy has been constructed. Two different methods for calculating counts in energy peaks from gamma emission spectra have been made and have been the basis for the further work. During this work the following has been determined: The efficiency of a high purity germanium (HPGe) detector, the activity of two different mushroom samples, the attenuation coefficient of gamma at 662 keV for these samples and for water. In order to be able to approximate a can filled with mushroom as an isotropic radiating point source and get accurate results, the activity measurements need to be carried out with a great distance between the sample and the detector. A consequence of this is that this approximation is only suitable for high-activity mushroom, which became evident when the activity of a low-activity mushroom could not be decided with decent statistics even though single measurements were carried out in almost a weeks time. Systematic errors are not considered during this work, only statistical uncertainties.
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Biodozimetrie pro osoby exponované zářením alfa: závislost na nádorovém onemocnění (exp. práce). / Biodosimetry for persons exposed to alpha radiation: dependence on malignity (exp. work).KŘÍŽOVÁ, Marcela January 2012 (has links)
In the thesis I focus on evaluation of the effect of familiar occurrence of cancer on presence and number of micro-nuclei in blood preparations with particular groups of persons. One of the biodosimetry methods, test for presence, number and kind of micro-nuclei, was used. I was not investigating the dosages as such and connection of the number of micro-nuclei with the dose, however, I followed up the effect of potentially influencing side factor on presence and number of micro-nuclei, which is the familiar occurrence of tumour. As a lot of information about ionizing radiation, its sources, radioactivity, radio-biologically important quantities, mechanisms of effects, molecular and cellular changes and biodosimetric methods as such falls under the topic, the theoretical part of diploma project is dedicated to such information. In the practical part, evaluation of the number and kind of micro-nuclei with set groups of persons is carried out. These groups of persons are particularly exposed to ? radiation. They are employees of spa Lázně Jáchymov, former miners from already closed uranium mines in Příbram and current miners from uranium mines GEAM o. z. Dolní Rožínka. These selected persons are divided according to their workplaces into two groups, i.e. a group of persons without cancer occurrence in the family and a group of persons with occurrence of cancer in their families. The numbers of bi-nuclei cells without micro-nuclei and with micro-nuclei and the kinds of micro-nuclei were determined with all these persons using fluorescence microscope. Expression and comparison of percentages of bi-nuclei cells with micro-nuclei to total number of all bi-nuclei followed and then expression and comparison of proportion of micro-nuclei without centromeres to the number of micro-nuclei of both kinds (with centromeres and without centromeres) with all persons and groups were carried out. Based on the results gained from statistical assessment, it was found that differences between percentages of the two main compared groups of persons did not show higher genomic instability (statistically significant difference) in persons with familiar occurrence of cancer than in persons without cancer in the family. But by comparing the shares of micronuclei without centromeres was proved statistically significant difference between these main groups.
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Hodnocení přístrojů používaných v AČR v případě radiační mimořádné události / Assessment of devices used by the Armed Forces of the Czech Republic in case of radiation emergency.LOŠKOVÁ, Romana January 2014 (has links)
This Thesis deals with the option of employing the Armed Forces of the Czech Republic (ACR) when a radiation emergency is imminent. Primarily, it focuses on evaluation of selected devices designed for radiation reconnaissance; summarising of radiation protection related legislation; and study of approved procedures. At its beginning, this Thesis tracks the origin of early detection systems at the territory of the then Czechoslovak Socialist Republic and their gradual evolution into the the existing form. From the radiation emergency point of view, this nationwide system represents a priceless help for monitoring of radioactive contamination dispersion and for warning. The following part sums up basic information on what is an ionizing radiation, how it comes into being and which basic quantities describe it. This part also contains basic type distinction, description of consequences for human organism and the most significant interactions of sources of ionizing radiation that could be misused with the most probability. This specific topic is introduced here because of the subsequent part of this Thesis being named Radiological Dispersion Device, or the dirty bomb. The significant part of this Thesis is the summary and classification of related legislation. The first documents referred to are two international standards. Publication 103 the 2007 Recommendations of the International Commission on Radiological Protection is dealing, inter alia, with dosing limits determining dose levels in planned exposure situations and reference levels used for emergency exposure situations and existing exposure situations. Publication 96 Protecting People against Radiation Exposure in the Event of a Radiological Attack is more substantial for this Thesis since it partly copes with the protection of front-line units including Integrated Rescue System (IRS) components and it specifies maximum exposure time for intervening personnel. Based on the IRS Catalogue of Typical Activities (STC 01/IZS), Materialised and Verified Use of a Radiological Weapon, the ACR would be one of the intervening components in such an attack. This Thesis analyses in detail individual ACR procedures starting with activities before employment, through threat prevention, event reaction to post-event activities like decontamination followed by monitoring of personnel contamination and their health condition. The practical part deals mainly with one of the Thesis´s goals which was evaluation of selected dosimetric devices used by the military for radiation reconnaissance. For this purpose, the quantitative research processing their main parameters was applied. The analysis within a selected sample was used for comparing and the sumary index IVi then showed the status of device applicability for contemporary use in radiation emergency. The pre-defined goals of this Thesis have been met implementing the above methods. The comparison of individual devices and their evaluation in respect to their applicability in joint radiation emergency operation with other IRS components has been carried out via discussion. It has been found out that some of the devices are obsolete and do not comply with the requirements for this job. This fact reflects the reality that these devices were designed in the period of a potential nuclear war. This corresponds with their robust structure and high level of sensitivity which is not desirable for a radiation emergency. The most severe problem, however, seems to be the fact that some devices measure quantities in old, no more used, units which could cause misinterpretation. On the other hand, other devices are modern, sensitive at low levels of dose input and offer real-time information on a well organised LCD display. To answer the question of ACR´s readiness to intervene in a radiation emergency one has to say that the ACR is ready to meet its rescue and consequence management tasks at a satisfactory level.
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Desenvolvimento da metodologia para síntese do poli(ácido lático-co-ácido glicólico) para utilização na produção de fontes radioativas / Development of methodology for the synthesis of poly(lactic acid-co-glycolic acid) for use in the production of radioactive sourcesPELEIAS JUNIOR, FERNANDO dos S. 09 October 2014 (has links)
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Caracterizacao radioquimica do sup(226)Ra, sup(40)K e dos isotopos de uranio e torio no fosfogessoPAES, VANESSA P. 09 October 2014 (has links)
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Disponibilidade de sup(238)U e sup(232)Th na utilização de fosfogesso na agricultura / Availability of sup(238)U and sup(232)Th in the utilization of phosphogypsum in agricultureMALHEIRO, LUCIANO H. 10 November 2014 (has links)
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Aplicação do Método de Monte Carlo no estudo da atividade obtida em sistema de coincidências 4π(β,EC)-γ pelo Método da Discriminação com reposição / Application of the Monte Carlo Method to the study of the activity obtained in a 4π(β,EC)-γ coincidence system by the Discrimination with Reposition MethodCORREA, GUSTAVO P. 22 June 2016 (has links)
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