Conditional sampling methods are generalized by applying a matched-filter on the reference signal. This generalized method is illustrated by data obtained in a magnetized toroidal plasma without rotational transform. By ...

En mulig forklaring på at universet gikk inn i en fase av akselerert ekspansjon for 5-6 milliarder år siden, er at energitettheten i universet inneholder et bidrag fra et dynamisk skalarfelt. Problemet med denne forklaringen ...

Two galaxy clusters, Abell 1351 and Abell 1995, are examined using weak gravitational lensing techniques. Mass maps are created, and the clusters' density and shear profiles are compared to theoretical predictions. Gravitational ...

Doktorgradsavhandlingen beskriver et programvarebibliotek utviklet av Øystein Olsen ved Institutt for teoretisk astrofysikk. Programvaren har blitt brukt til å finne regioner med stabile og ustabile baner rundt asteroider ...

In between the Cosmic Microwave Background (CMB) and the instrument there are other sources of radiation, called foregrounds. The foregrounds radiate in the same frequency bands as the background, and cause contamination ...

Observations of the Cosmic Microwave Background is impaired by other astrophysical sources that also radiate in the microwave spectrum. These other, non-CMB sources are known as foregrounds. In this thesis, three different ...

The thesis examines the relation between the magnetic field as measured by MDI and the continuum intensity at four different wavelengths (1319, 1199, 1037 and 910Å) as measured by SUMER. A method for copointing the instruments ...

It is believed that the Broad Emission Line Region of Quasars consists of discrete clouds. Due to the suspected small size of a cloud, the radiation from clouds may be strongly amplified by gravitational microlensing. It ...