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Eksploatacja Cyklotronu AIC - 144 przystosowanego do celów medycznych cz. 4
No full textIn 2016, eye therapy was transferred to the new Proteus-235 cyclotron. The work of Cyclotron AIC-144 has become research and development. Reducing the demand for a proton beam has contributed to significant advances in the modernization of the device. This report shows the current status of the cyclotron and presents the work that was made in 2016 and 2017: modernization of the control panel, reconstruction of the irradiation station in the experimental hall and a new program for controlling the power supplies
Study of charmed mesons in B decays in the Belle experiment
No full textNiniejsza praca dotyczy badania klasy podwójnie powabnych rozpadów z dziwnością B -> D^(*)D^(*)_s(J). Pomiary przeprowadzono w oparciu o rozkłady masy brakującej w inkluzywnych przejściach B ->D^(*)X, a zatem w sposób wolny od założeń o rozpadach rezonansów D^(*)_s(J). Badania zostały wykonane na próbce danych równej 772x10^6 par mezonów BB-bar zarejestrowanych w detektorze Belle pracującym na akceleratorze KEKB, który jest zderzaczem e^+e^- o asymetrycznych energiach wiązek i całkowitej energii w układzie środka masy równej masie rezonansu Y(4S).
Zostały wyznaczone następujące częstości rozgałęzień dla rozpadów B do stanów
D^(*)D_s^(*):
ẞ(B^+ -> D^0D_s^+) = (0,82 ± 0,02 ± 0,07 ± 0,04)%,
ẞ(B^+ -> D^0D_s^*+) = (0,66 ± 0,03 ± 0,06 ± 0,04)%,
ẞ(B^+ -> D^*0D_s^+) = (0,70 ± 0,12 ± 0,07 ± 0,05)%,
ẞ(B^+ -> D^*0D_s^*+) = (2,46 ± 0,09 ± 0,25 ± 0,18)%,
ẞ(B^0+ -> D^-D_s^+) = (0,73 ± 0,04 ± 0,07 ± 0,03)%,
ẞ(B^0 -> D^-D_s^*+) = (0,84 ± 0,03 ± 0,08 ± 0,04)%,
ẞ(B^0 -> D^*-D_s^+) = (0,70 ± 0,05 ± 0,07 ± 0,02)%,
ẞ(B^0 -> D^*-D_s^*+) = (1,56 ± 0,03 ± 0,15 ± 0,05)%,
oraz dla rozpadów B do stanu wzbudzonego Ds1(2460):
B(B+ -> D¯0Ds1(2460)+) = (0,17 ± 0,05 ± 0,015 ± 0,08)%,
B(B+ -> D¯*0Ds1(2460)+) = (0,93 ± 0,17 ± 0,09 ± 0,07)%,
B(B0 -> D-Ds1(2460)+) = (0,29 ± 0,06 ± 0,03 ± 0,01)%,
B(B0 -> D*-Ds1(2460)+) = (0,74 ± 0,08 ± 0,07 ± 0,02)%.
Przytoczone niepewności pomiarów oznaczają kolejno błędy: statystyczny, systematyczny oraz związany z niepewnością stosunków rozgałęzień dla rozpadów rezonansów pośrednich występujących w badanych procesach. Uzyskane dokładności wyznaczenia częstości rozpadów są porównywalne lub dokładniejsze niż publikowane średnie światowe.The thesis presented here concerns the study of double charmed decays with strangeness B -> D^(*)D_s(J)^(*). The measurements were based on the missing mass distributions in inclusive transitions B -> D^(*)X, and thus in a way free from the assumptions about resonance decays D_s(J)^(*). In the analysis was used the data sample equal to 772x10^6 BB-bar meson pairs registered by the Belle detector operating on the KEKB accelerator , which is e^+e^- collider with asymmetric beam energies and total energy in the center of mass system corresponding to the mass of the Y(4S) resonance.
Branching ratios for the B decays involving ground cs-bar mesons have been measured to be:
D^(*)D_s^(*): ẞ(B^+ -> D^0D_s^+) = (0,82 ± 0,02 ± 0,07 ± 0,04)%, ẞ(B^+ -> D^0D_s^*+) = (0,66 ± 0,03 ± 0,06 ± 0,04)%, ẞ(B^+ -> D^*0D_s^+) = (0,70 ± 0,12 ± 0,07 ± 0,05)%, ẞ(B^+ -> D^*0D_s^*+) = (2,46 ± 0,09 ± 0,25 ± 0,18)%, ẞ(B^0+ -> D^-D_s^+) = (0,73 ± 0,04 ± 0,07 ± 0,03)%, ẞ(B^0 -> D^-D_s^*+) = (0,84 ± 0,03 ± 0,08 ± 0,04)%, ẞ(B^0 -> D^*-D_s^+) = (0,70 ± 0,05 ± 0,07 ± 0,02)%, ẞ(B^0 -> D^*-D_s^*+) = (1,56 ± 0,03 ± 0,15 ± 0,05)%,
whereas the branching ratios measured for the channels with an excited D_s1(2460) are:
B(B+ -> D¯0Ds1(2460)+) = (0,17 ± 0,05 ± 0,015 ± 0,08)%, B(B+ -> D¯*0Ds1(2460)+) = (0,93 ± 0,17 ± 0,09 ± 0,07)%, B(B0 -> D-Ds1(2460)+) = (0,29 ± 0,06 ± 0,03 ± 0,01)%, B(B0 -> D*-Ds1(2460)+) = (0,74 ± 0,08 ± 0,07 ± 0,02)%.
The uncertainties quoted are due to statistics, experimental systematic errors and uncertainties of branching fractions for the decays of intermediate resonances for a given channel. The quoted precisions are similar or better than world averages.14
Analiza ograniczeń systemu Proteus 235 wynikających z zastosowanej technologii akceleracji oraz diagnostyki wiązki protonów, w zastosowaniach do eksperymentów fizyki jądrowej
No full textThe purpose of the report is to introduce work necessary to determine impact of selected cyclotron Proteus C-230 parameters affecting workflow of Proteus 235 Proton Therapy System, which is located inside Institute of Nuclear Physics in Cracow. In particular, the properties of produced ion beam such as the stability and cross-section shape of the beam were analyzed. Gathered data from conducted research will be utilized primarily during beam optics re-work for nuclear physics experiments and also during daily operation of the cyclotron
Calculations of the neutron-induced activity in air inside the Cuboid 2 of the High-Resolution Neutron Spectrometer for ITER
No full textThis report presents results of the calculations performed in order to predict the neutron - induced activity in air inside the second Cuboid in the ITER equatorial port cell #1 where the Time of Flight detectors of the High Resolution Neutron Spectrometer are planned to be installed. Based on the neutron spectra generated by 2.45 MeV and 14 MeV neutron sources, calculated with the MCNP code, it was possible to determine the activity of the dominant radionuclides using the FISPACT-II Transmutation - Activation Inventory Code and the EAF - 2010 nuclear data library. The results show that although long - lived isotopes such as e.g. H-3 or C-14 are produced following neutron irradiation, their activity will not be significant since they will not exceed the maximum permissible levels.Fusion for Energy (F4E) research program under grant agreement No F4E-GRT-403 (DG
Mechanical analysis of mirror panels used in CTA (Cherenkov Telescope Array)
No full textThis paper presents results of numerical simulations of a three-layer rectangular plate and a rotationally symmetric plate, as well as panels of mirrors produced for the project Cherenkov Telescope Array - the CTA. Calculations were based on the finite element m
ethod and were prepared using ANSYS program. The problem of the three-layer rectangular plate and the rotationally symmetric plate loaded by bending moments on the edge was presented, with appropriate assumptions in the analysis. The theory of small and large deflections were analyzed and compared by the calculations. The curvature values at the middle and the end of plates were searched. Also bending moments needed to obtain the appropriate values of curvature were examined. Glass panels as a main part of CTA mirrors were described. The boundary conditions and loads, material properties were showed as well as the adopted assumptions in the analysis. Two cases were considered with two values of different radius of curvature. State of deformations and stresses which prevails in those parts of mirrors were checked. The results were depicted in the form of graphs of the radius of curvature and values of stresses for different values of mirror panel radius. Two methods, simple geometric and polynomial approximation, were used by which it was possible to approximate of radius of curvature changes in different places of panels after unloading the system
Positron annihilation spectroscopy on a beam of positrons the LEPTA facility
No full textThe results and possibilities of the samples surfaces research by
the Doppler method of positron annihilation spectroscopy (PAS) for a
monochromatic beam of positrons at the LEPTA facility are presented in
this paper. Method with high-resolution sensitivity to defects like
vacancies and dislocations allows scanning of the surface and near-surface
sample layers to a depth of several micrometers by the method of Doppler
broadening of annihilation lines. The opportunities for the development of
a PAS method based on the measurement of the positron lifetime in the
sample irradiated by ordered flow of positrons from the injector of
accelerator complex LEPTA at JINR are discussed
Opracowanie algorytmów do analizy zdjęć z mikroskopii fluorescencyjnej
No full textThe fluorescence microscopy is one of the fastest techniques of DNA damage visualisation induced by physical or chemical factors. For this reason, the area of algorithms for images analysis from fluorescence microscopy continually develops. This report contains presentation of algorithms elaborated for the assessment of relative amount of DNA damage, visualised with the fluorescent dyes Alexa Fluor 488 and DAPI. Methods of the determination of the noise level and signal to noise ratio in the images, as well as methods of noise reduction and image quality optimization have been presented.The Małopolska Regional Operational Programme Measure 5.1 Krakow Metropolitan Area as an important hub of the European Research Area for 2007- 2013, project No. MRPO.05.01.00-12-013/1
Wpływ kontrolowanej modyfikacji struktury i morfologii planarnych i liniowych nanostruktur metalicznych na ich własności magnetyczne na przykładzie wielowarstw Fe/Cr i nanodrutów Co
No full textIn this monography, we have demonstrated the results of an investigation of the influence of controlled modification of the morphology and structure on magnetic and magnetotransport properties of Fe/Cr multilayers representing planar nanostructures. Moreover, the structural and magnetic properties of cobalt nanowires being an example of linear objects were studied. The aim of the multilayer studies was to learn about the interface structure between Fe and Cr layers and then analyse the impact of this parameter on the giant magnetoresistance effect. Samples were prepared by vapor deposition in ultrahigh vacuum conditions. The layer morphology and interface structure were analyzed using the techniques of high resolution transmission electron microscopy on a cross section of the sample (HRTEM) also operated in the scanning mode (STEM), low energy electron diffraction (LEED), energy dispersive spectroscopy (EDS), Auger electron spectroscopy (AES), X-ray reflectometry (XRR) and conversion electron Mossbauer spectroscopy (CEMS). The results confirmed the slight interface roughness in the area of up to 2 - 3 atomic layers and layer continuity in all samples. An analysis of the magnetic properties carried out based on measurements of magnetooptical Kerr effect or SQUID magnetometer, indicated the antiferromagnetic coupling of Fe layers. In order to analyse the impact of interface roughness on the giant magnetoresistance value, the multilayer systems have been subjected to the controlled modification by the introduction of Bi, Pb or In surfactants as well by gold or iodine swift heavy ion irradiation. The used modification methods, depending on the type and intensity, caused the interface smoothing, which is preferably influenced by the presence of the buffer layer, the introduction of bismuth atoms as surfactant, as well as Au and I ion irradiation of polycrystalline trilayers with low fluences. In addition, we have observed changes in the magnetic arrangement of Fe layers, manifested by a decrease of antiferromagnetic coupling fraction in multilayers modified by In surfactant and in the majority of irradiated samples. The increase of the antiferromagnetic coupling fraction was observed for trilayers irradiated with low fluences, for which interface smoothening was reported. It has been demonstrated that the positive effect of the buffer layer caused the stabilisation of the antiparallel arrangement of magnetization vector in iron layers. These changes affected the giant magnetoresistance effect, which increased with increasing interface roughness caused by interface corrugation and less by interdiffusion, with kept antiferromagnetic coupling of Fe layers. An increase of interface roughness resulted mainly from interdiffusion, and it was responsible for magnetoresistance effect decrease amplified by decrease of antiferromagnetic coupling fraction. Modification of interfaces with swift heavy ions showed that irradiation with small ion fluences gives the best chance of interface smoothing and keeping antiferromagnetic ordering of the systems.
The aim of investigation of the structural and magnetic properties of cobalt nanowires was to optimise their morphology, as well as electrodeposition parameters leading to the achievement of nanoobjects showing a magnetic anisotropy with an easy axis of magnetization along the nanowire and characterised by the high values of coercivity and squareness of the hysteresis loop. Cobalt nanowires were electrodeposited in the polycarbonate membranes with a diameter in the range of 30 nm to 200 nm. The nanowire length varied from 1.5 μm to 6 μm. The impact of electrodeposition parameters, such as temperature and pH of the electrolyte and the cathodic voltage on the properties of the nanowires, was also investigated. It was observed that the optimal to achieve magnetic arrangement along nanowire axis and the greatest values of the coercive field, are: small diameters (30 nm ÷ 50 nm) and small length of the nanowires (1.5 μm), low electrolyte temperature (20 °C - 25 °C), low cathodic voltage (-0.9 ÷ V - 1.0 V) and moderate pH value (3.2) with a tendency to increase in order to reduce hydrogen evolution (3.8). These observations provide the basis for ongoing studies of composed nanowires made from alternating electrodeposited layers of Co and Cu, Fe and Cu as well as Fe and Cr layers
Searches for New Physics effects in b →sl-sl+ transitions
No full textThe dissertation aims at presenting the current situation in the measurements of electroweak
penguin diagrams dominated decays: b → sl−l+1 . These decays have been a smoking gun
for hunting for New Physics effects over many years, but in the last three years the research
on these phenomena has intensified due to new measurements. Enormous progress has
been made both on the theoretical and the experimental sides to understand the measured
deviations from the current Standard Model predictions, referred to in what follows as
“anomalies”. The author of this dissertation has been one of the main authors of the angular analysis
of B0→ K∗ 0µ+µ− decay in the LHCb experiment, which has been widely regarded as one
of the most important results of the flavour physics sector in recent years. He has proposed
a method called “the method of moments” to measure the angular terms of this decay,
which he has later successfully applied in the measurement itself. Moreover, he has been
the driving force behind the two other important analyses in LHCb: the measurement of
the angular distribution and branching ratio of the B0→ K∗ 0 (1430)µ+µ− decay, where again the method of moments has been used to obtain the angular coefficients, and the search for the light scalar particle that can be produced in the b → s transitions and that decays to a dimuon pair. In this case no signal has been observed and the upper limits on the branching fraction have been set, later to be used for constraining the inflaton model.
The dissertation is organized as follows: the brief introduction is followed by, the second
chapter devoted to a theoretical description of rare B decays, where the effective field
theory formalism is introduced. Furthermore, the author discusses the current theoretical
problems in calculating the Standard Model predictions for the b → sl−l+ processes. Last but not least, the optimised angular observables that are less dependent on the form
factors uncertainness are derived. The third chapter describes the experimental apparatus
used in the b → sl−l+ measurements. Special focus is put on the sub-detectors that play
an important role in the studies of b → sl−l+ transitions. Chapters 4, 5, 6 are devoted to
describing the data analyses performed by the author in the LHCb experiment. In Chapter 7
the global analysis of electroweak penguin decays is presented. This kind of global analysis
has become extremely popular in the past few years as it helps to constrain and pin down those New Physics models that are likely to be responsible for the observed anomalies. The
author of this monograph is involved in one of the biggest collaborations performing New
Physics fits, where he is the convenor of the Flavour Working group. Furthermore, the
author presents his own study on separating the long distance effects in the B0→ K∗ 0µ+µ−decay. This is the state of the art way of determining those contributions. The chapter ends with a description of possible New Physics models that can explain the observed discrepancies
Wpływ krzywizny, struktury podłoża i warstwy wierzchniej na propagację fal i rezonansów na powierzchniach oraz złączach materiałów sprężystych
No full textW niniejszej pracy przedstawiony został teoretyczny opis dynamiki powierzchni oraz wpływ krzywizny, w konkretnym przypadku wydrążenia cylindrycznego, na dynamikę powierzchni i złącza dwóch izotropowych ośrodków sprężystych. Przeanalizowany został szeroki zakres parametrów materiałowych, w którym możliwe jest występowanie fal i rezonansów powierzchniowych oraz innych zjawisk związanych z istnieniem powierzchni, m.in. takich jak konwersja modów w odbiciu i przejściu tj. pojawienie się fal odbitych lub przechodzących o innych polaryzacjach niż fala padająca oraz brak konwersji modów przy odbiciu od granicy ośrodka. Opisany jest również wpływ pokrycia takich powierzchni cienką warstwą wierzchnią, z uwzględnieniem szerokiego spektrum parametrów sprężystych materiałów włącznie z zyskującymi od lat 80-tych XX w. coraz większe zainteresowanie i zastosowanie praktyczne auksetykami, tj. materiałami o ujemnym współczynniku Poissona. Materiały te zwiększają swe rozmiary poprzeczne przy rozciąganiu. W porównaniu do konwencjonalnych materiałów auksetyki mogą odgrywać istotną rolę przy projektowaniu nowego typu urządzeń. Wymienia się je także wśród materiałów mogące posłużyć za protezy tętnicze. Ciekawe, że w istnienie materiałów auksetycznych wątpiono aż do roku 1986 [19], mimo, że fakt stabilności izotropowych ośrodków sprężystych w zakresie ilorazu Poissona −1 < ν < 0 był znany od już w XIX w.11