Sökning: "Sun: oscillations"
Visar resultat 1 - 5 av 6 avhandlingar innehållade orden Sun: oscillations.
1. Constraints on the gas temperature in the solaratmosphere from multiwavelength inversions
Sammanfattning : In this Licentiate thesis I review the properties of the solar atmosphere and the diagnostic value ofdifferent spectral lines in the visible and ultraviolet (UV) along with the millimeter (mm) continua in theelectromagnetic spectrum of the Sun.While the solar atmosphere has been routinely observed in high-resolution from ground-based opti-cal telescopes such as the Swedish Solar Telescope (SST), and more recently in the UV from space tele-scopes such as the Interface Region Imaging Spectrograph (IRIS), radio observations lag behind despitetheir great usefulness. LÄS MER
2. Towards semi-automation of forestry cranes : automated trajectory planning and active vibration damping
Sammanfattning : Forests represent one of the biggest terrestrial ecosystems of Earth, that can produce important raw renewable materials such as wood with the help of sun, air and water. To efficiently extract these raw materials, the tree harvesting process is highly mechanized in developed countries, meaning that advanced forestry machines are continuously used to fell, to process and to transport the logs and biomass obtained from the forests. LÄS MER
3. The Sun as a laboratory for particle physics
Sammanfattning : In the paper attached to this thesis, Paper I, we have calculated the flux of neutrinos that emanate from cosmic ray collisions in the solar atmosphere. These neutrinos are created in the cascades that follow the primary collision and can travel from their production point to a detector on Earth, interacting with the solar material and oscillating on the way. LÄS MER
4. Plasma environment of an intermediately active comet : Evolution and dynamics observed by ESA's Rosetta spacecraft at 67P/Churyumov-Gerasimenko
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
5. Cosmogenic radionuclides in environmental archives – A paleo-perspective on space climate and a synchronizing tool for climate records
Sammanfattning : The Sun is the primary source for Earth’s climate system. Its fluctuations in irradiance are also known to have an impact on climate. In addition, changes in solar activity modulate the atmospheric production rates of cosmogenic radionuclides (e.g. LÄS MER
