The information about the electron population of a helicon source plasma that expands along a magnetic nozzle is important for understanding the plasma acceleration across the potential drop that forms in the nozzle. The electrons need an energy higher than the potential drop to escape from the source. At these energies the signal of a Langmuir probe is less accurate. An inverted RFEA measures the ...

Observasjoner av Vega og Fomalhaut tyder på at de har støvbelter rundt seg. Avstanden fra stjerna er rundt 0,2 astronomiske enheter (AE) og størrelsen til støvpartiklene varierer fra noen nanometer til noen mikrometer. Slikt støv fins også i solsystemet. Denne oppgaven handler om å beregne banen til slike støvpartikler etter danning. Det antas at støvet påvirkes av tre krefter: gravitasjon, ...

We study the effect of changing the separation grid bias in a double plasma device from -50 V to the same bias as the anode in the source chamber, 115 V on the plasma and beam parameters downstream in the target chamber. Two different probes were used to analyze the downstream plasma. We used an RFEA-probe to obtain information about the ions, such as the ion energy distribution and we constructed ...

In the context of global warming, Arctic sea ice has declined substantially during the satellite era (Kwok 2018). The retreating and thinning of Arctic sea ice provide opportunities for human activities in the Arctic, such as tourism, fisheries, shipping, natural resource exploitation, and wildlife management; however, new risks emerge. To ensure the safety and emergency management of human activities ...

A new concept has been developed which can view vast regions of the Earth's surface. Ground HF transmissions are reflected by the ionosphere to illuminate the ocean over a few thousand kilometers. HF receivers detect the radio waves scattered by the sea and land surface. Using the theory of radio wave scatter from ocean surfaces, the HF data is then processed to yield the directional wave-height ...

Optical-lattice illumination patterns help in pushing high spatial frequency components of the sample into the optical transfer function of a collection microscope. However, exploiting these high-frequency components require precise knowledge of illumination if reconstruction approaches similar to structured illumination microscopy are employed. Here, we present an alternate blind reconstruction ...

A new blob-tracking algorithm for the GPI diagnostic installed in the outboard-midplane of Alcator C-Mod is developed. I t tracks large-amplitude fluctuations propagating through the scrape-off layer and calculates blob sizes and velocities. We compare the results of this method to a blob velocity scaling from a simple blob-model for sheath-connected blobs. We further present initial results from a ...

In the past years the Norwegian PV market has grown substantially. The importance of data on how PV systems perform in Norway is therefore also increasing. In this thesis several Norwegian PV systems are analyzed mainly in terms of annual specific yields. The systems are located in western and southeastern Norway and near horizontal, tilted and vertical modules are looked at. Results show pretty ...