Sökning: "polarimetry"
Visar resultat 6 - 10 av 13 avhandlingar innehållade ordet polarimetry.
6. Optical Studies For Synchrotron Radiation Beamlines
Sammanfattning : Synchrotron radiation sources have greatly contributed to the progress in many fields of science. The development of the storage ring technologies has made possible to obtain very low emittance electron beams, which together with the use of undulators allow guiding a very high photon flux into a very small spot required by the experiments. LÄS MER
7. Design and development of a microwave multifrequency polarimetric scatterometer for biosphere remote sensing
Sammanfattning : Microwave radar and radiometer techniques are used to gather crucial information about the earth and its atmosphere. The ERS-1, JERS-1, RadarSAT and NASA’s Mission to Planet Earth projects are designed to study the changing global environment. In all these endeavors, the key instrument is the radar or scatterometer. LÄS MER
8. The diagnostic potential of the He I D3 spectral line in the solar atmosphere
Sammanfattning : The research question of my PhD is in a way a simple one: what can observations of the He I D3 line teach us about the solar chromosphere? This optical spectral line at 5876 Å is generally formed in the upper chromosphere, and is sensitive to the local magnetic field. The He I D3 line is also indirectly sensitive to heating of the transition region and corona, since it is resulting from a transition that occurs between levels in the triplet system of neutral helium. LÄS MER
9. Position-sensitive germanium detectors for gamma-ray tracking, imaging and polarimetry
Sammanfattning : Modern germanium detectors are often manufactured with two-dimensionally segmented electrical contacts. Signals induced in each segment are read out simultaneously when a photon is detected. Detailed pulse shape analysis (PSA) of these signals allows to resolve positions of individual γ-ray interactions with a precision of at least a few mm. LÄS MER
10. High-contrast imaging of faint substellar companions and debris disks
Sammanfattning : Star formation results in the accumulation of circumstellar material orbiting around their host stars, such as debris disks and planetary-mass objects. A relatively modern technique that has shown to be very valu- able for studying these faint companions is high-contrast imaging, which allows to distinguish the light emitted or scattered off these objects, otherwise hidden behind the brighter stellar halo. LÄS MER