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An inverse source problem associated with a semi-linear transport or one-way wave equation in one spatial dimension is considered. It is shown an analytic solution to the inverse problem can be given and furthermore, that this inverse problem of determination of a source function is ill-posed, and must be regularised. A novel regularisation scheme which combines least squares monotone approximatio

Industry involvement in open source software development has become a popular practice among companies which, e.g., share software development costs with other community participants or implement an open source based business model. An increased understanding of the underlying development structure, especially in a case where the community participants are composed of competing industry members, c

Popular Abstract in Swedish I denna avhandling presenteras en ny typ av röntgenkälla baserad på ett laser-producerat plasma. Röntgenstrålning alstras genom att fokusera laserpulser på ett strålmål. Energin i de enskilda laserpulserna blott är cirka 150 mJ, men tack vare den extremt korta pulstiden 100 fs (10E-13 s), blir laserns toppeffekt mer än 1 TW (10E12 W). Den extremt intensiva laserstrålninA laser-produced plasma was generated by focusing 100 fs laser pulses, with an energy of 150 mJ, onto metal targets. The laser intensity was expected to reach 10E17 W/cm2. Radiation was emitted from the created plasma, with photon energies extending up to the MeV regime. The laser-based X-ray source was optimised, with the purpose of making it a realistic source of hard X-rays (>10 keV). Dedicated

Neutral particle oscillations have proven to be extremely valuable probes of fundamental physics. For instance, kaon oscillations provided us with our first insight into CP-violation, B oscillations form the most fertile ground for the continued study of CP-violation, and neutrino oscillations suggest the existence of a new, important energy scale well below the GUT scale. Neutrons oscillating int

Hard X-rays are generated by focusing 110 fs laser pulses with intensities of about 10¹⁷ W·cm^-2 onto solid metal targets. Characteristic properties of this X-ray source are the small source size, the short pulse duration and the high peak flux. The aim of the present work was to characterise this X-ray source and to demonstrate possible applications. A comparison with other X

Plasma accelerators present one of the most suitable candidates for the development of more compact particle acceleration technologies, yet they still lag behind radiofrequency (RF)-based devices when it comes to beam quality, control, stability and power efficiency. The Horizon 2020-funded project EuPRAXIA ("European Plasma Research Accelerator with eXcellence In Applications") aims to overcome t

In laser-wakefield acceleration (LWFA), a femtosecond laser pulse is tightly focused in a gas to intensities exceeding 1018 W/cm2 . The laser radiation ionizes the medium and excites a plasma wave that travels behind the laser pulse. Electrons can be trapped in the oscillations in the plasma density, where electric fields of the order of several hundreds of GV/m accelerate them to relativistic ene

A laser-driven electron-storage ring can produce nearly monochromatic, tunable X-rays in the keV energy regime by inverse Compton scattering. The small footprint, relative low cost and excellent beam quality provide the prospect for valuable preclinical use in radiography and tomography. The monochromaticity of the beam prevents beam hardening effects that are a serious problem in quantitative det

Registered- and community health nurses in municipal home care (hereafter referred to as home care nurses) have a demanding job that is special compared to other forms of healthcare. The work is mobile, and care in the field is often carried out in solitude. At the same time, the patients being cared for often have complex care needs, requiring cooperation and interaction. Contact with colleagues

Extremophiles, the microorganisms inhabiting different extreme environments char-acterized by high or low temperature, high or low pH, high salt concentration, high pressure, high radiation, etc. or combinations thereof, have developed unique strate-gies for adapting and thriving in such environments. Studies on extremophiles have been pursued with great interest to determine the mechanism

The effect of relic gravitational waves on the polarization of the CMB is analytically studied. The equation of radiative transfer for the polarization is transformed into two coupled differential equations by Polnarev's method and an approximate solution is derived.

The use of laser based plasma x-ray sources (LPXS) has quickly expanded during the past decades due to rapid development of ultrafast laser systems. These sources are used in many research applications such as emission, absorption and particularly time-resolved spectroscopy. From the LPXS x-ray pulses are generated when an intense laser pulse is focused onto a liquid or solid interface in gas or v