Sökning: "Polarization measurements"

Visar resultat 16 - 20 av 147 avhandlingar innehållade orden Polarization measurements.

  1. 16. Plasma environment of an intermediately active comet : Evolution and dynamics observed by ESA's Rosetta spacecraft at 67P/Churyumov-Gerasimenko

    Författare :Elias Odelstad; Anders Eriksson; Andrew Coates; Uppsala universitet; []
    Nyckelord :Rosetta; comet; 67P; RPC-LAP; RPC-MIP; RPC-ICA; RPC-MAG; ROSINA-COPS; Langmuir probe; spacecraft potential; plasma; Churyumov-Gerasimenko; ion composition analyzer; diamagnetic cavity; ion velocity; electron temperature; ion-neutral drag; collisional coupling; wake effects; filamentation; electron cooling; plasma waves; hybrid waves; Bernstein waves; minimum variance; polarization; wavelet; density fluctuations; magnetic field oscillations; drift-cyclotron instability; asymmetric plasma and magnetic field enhancements; Fysik med inriktning mot rymd- och plasmafysik; Physics with specialization in Space and Plasma Physics;

    Sammanfattning : The subject of this thesis is the evolution and dynamics of the plasma environment of a moderately active comet before, during and after its closest approach to the Sun. For over 2 years in 2014-2016, the European Space Agency’s Rosetta spacecraft followed the comet 67P/Churyumov-Gerasimenko at distances typically between a few tens and a few hundred kilometers from the nucleus, the longest and closest inspection of a comet ever made. LÄS MER

  3. 17. Nematic Liquid Crystal Spatial Light Modulators for Laser Beam Steering

    Författare :Emil Hällstig; Mikael Lindgren; Lars Sjöqvist; William Crossland; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; spatial light modulator; liquid crystal; beam steering; tracking; phase modulation; fringing field; director distribution; finite-difference time-domain; polarization; temporal properties; Fysik; Physics; Fysik;

    Sammanfattning : Laser beam control is important in many applications. Phase modulating spatial light modulators (SLMs) can be used to electronically alter the phase distribution of an optical wave-front and thus change the direction and shape of a laser beam. LÄS MER

  4. 18. Tilted Foils Nuclear Spin Polarization at REX-ISOLDE

    Författare :Hans Törnqvist; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; beta-NMR; ISOLDE; tilted foils; particle scattering; post-acceleration; REX-ISOLDE; nuclear spin polarization; HIE-ISOLDE;

    Sammanfattning : This thesis will explain and summarize my work and involvement in experiments aimed at producing nuclear spin polarization of post-accelerated beams of ions with the tilted-foils technique at the REX-ISOLDE linear accelerator at CERN. Polarizing the nuclear spin of radioactive beams in particular may provide access to observables which may be difficult to obtain otherwise. LÄS MER

  5. 19. Molecular Recognition Mechanisms: Thermodynamics and Polarization Spectroscopy of DNA--Intercalator Complexes

    Författare :Hans-Christian Becker; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; groove-binding; DNA; intercalation; linear dichroism; polarization spectroscopy; thermodynamics; enthalpy--entropy compensation;

    Sammanfattning : Mechanisms for molecular recognition in DNA--intercalator complexes have been investigated by optical spectroscopy. The effect of electrical charge on binding geometry and binding thermodynamics was studied using 2,7-diazapyrene (DAP) and its N-methylated cations DAP+ and DAP2+ as model ligands. LÄS MER

  7. 20. Geoelectrical imaging for interpretation of geological conditions affecting quarry operations

    Författare :Mimmi K. Magnusson; Joanne Fernlund; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electrical resistivity imaging; Rock-mass quality; Aggregate production; Geophysical methods; Induced polarization; Normalized induced polarization; Environmental engineering; Miljöteknik;

    Sammanfattning : Determination of the subsurface geology is very important for the rock quarry industry. This is primarily done by drilling and mapping of the surface geology. However in Sweden the bedrock is often completely covered by Quaternary sediments making the prediction of subsurface geology quite difficult. LÄS MER