Nuclear physics tells us a lot about astrophysics, particularly the energy generation in stars. The present work is a thesis in experimental nuclear physics, reporting the results of 30S radioactive beam development for a future experiment directly measuring data to extrapolate the 30S(α,p) stellar reaction rate in Type I X-ray bursts, a phenomena where nuclear explosions occur repeatedly on the surface of accreting neutron stars. On the astrophysics side, the work details basic stellar physics and stellar reaction formalism in Chapter 1, the behaviour of compact stars in Chapter 2, and a full literature review of Type I X-ray bursts in Chapter 3. Nuclear experiments are non-trivial, and the results reported here were not accomplished by the author alone. Stable-beam experiments are technically challenging and involved, but for the case at hand, the halflife of 30S is a mere 1.178 seconds, and in order to measure reaction cross-sections, we must make a beam of the radionuclide 30S in situ and use these rare nuclei immediately in our measurement. Particle accelerator technology and radioactive ion production are treated in Chapter 4, and the experimental facility and nuclear measurement techniques are discussed in some detail in Chapter 5. In order to perform a successful future experiment which allows us to calculate the stellar 30S(α, p) reaction rate, calculations indicate we require a 30S beam of ~ 10^5 particles per second at ~ 32 MeV. Based on our recent beam development experiments in 2006 and 2008, it is believed that such a beam may be fabricated in 2009 according to the results presented in Chapters 6 and 7. We plan to measure the 4He(30S,p) cross-section at astrophysical energies in 2009, and some remarks on the planned (α,p) technique are also elucidated in Chapters 5, 6 and 7. / Thesis / Master of Science (MSc)

The degradation of bridge edge beam systems in Sweden entailed the study of new alternativedesigns, which may become more optimal from a life-cycle perspective than the currenttypical solution used (concrete integrated). Subsequently, a U-shaped steel edge beamproposed by the consulting engineering group Ramböll was considered by the SwedishTransport Administration for its use in a real bridge project. This thesis follows theimplementation of this alternative in a bridge project.The goals of the thesis are to study the development of the U-shaped steel edge beam solutionin the case study, and to identify the key factors behind it. The case study consists of a roadframe bridge where a heavily damaged bridge edge beam system is going to be replaced.For the structural design of the solution, a static linear analysis of a vehicle collision has beencarried out with the help of Finite Element Modelling and current codes. The report shows themodelling of the design solution throughout different development phases in the project. Thecommercial software used has been LUSAS.As an outcome of the project, four models have been designed and analysed, two of themdeveloped by the author as proposed solutions. The factors behind the different changes in thedesign have been identified as: (1) structural resistance, (2) constructability and (3) the use ofstainless steel. Moreover, the connection between the steel edge beam and the concrete slabhas been the main critical part for the structural resistance. Finally, the current preliminarymodel at the moment this thesis is written, which was proposed in the project meetings, meetsthe requirements from a structural point of view.