Search for dissertations about: "main sequence stars"

Showing result 1 - 5 of 16 swedish dissertations containing the words main sequence stars.

  2. 1. Interacting Giants and Compact Stars

    Author : Alexey Bobrick; Astronomi - Genomgår omorganisation; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; stars Binaries: General; stars : neutron; stars : subdwarfs; stars : supergiants; hydrodynamics; nuclear reactions; nucleosynthesis; abundances; stars Binaries: General; stars : neutron; stars : subdwarfs; stars : supergiants; hydrodynamics; nuclear reactions; nucleosynthesis; abundances; Fysicumarkivet A:2021:Bobrick;

    Abstract : This thesis is based on four papers dealing with various aspects of interactions in binary stars. Interactions between stars occur at nearly all stages of their evolution and can take many forms. READ MORE

  4. 2. Magnetic fields of cool stars from near-infrared spectropolarimetry

    Author : Alexis Lavail; Oleg Kochukhov; Nikolai Piskunov; Gaitee Hussain; Jeff Valenti; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; stars: magnetic field; stars: pre-main-sequence; stars: late-type; techniques: spectroscopic; techniques: polarimetric; Astronomy; Astronomi;

    Abstract : Magnetic fields rule many physical processes in and around stars throughout their lifetime. All cool stars possess a magnetic field, likely generated by dynamo processes. In order to properly understand the evolution of cool stars, we need to understand their magnetism. READ MORE

  5. 3. Studies of the S-type AGB star W Aquilae : The circumstellar envelope and the fain companion

    Author : Taissa Danilovich; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; stars: binaries: spectroscopic; circumstellar matter; stars: binaries: visual; stars: evolution; stars: mass-loss; stars: AGB and post-AGB; stars: individual: W Aql;

    Abstract : Low- and intermediate-mass stars will all eventually enter the asymptotic giant branch (AGB) phase. AGB stars experience intense mass-loss, generating a significant fraction of the dust and molecular matter that enrichesthe ISM. AGB stars are also responsible for a the production of about half of all elements heavier than iron. READ MORE

  6. 4. Dwarf and Subgiant Stars as Probes of Galactic Chemical and Dynamical Evolution

    Author : Patrik Thorén; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Astronomy; Abundances; atomic data; Galactic evolution; late-type stars; main sequence stars; subgiants; Pop II; Pop I; stellar evolution; Astronomi; Astronomy and astrophysics; Astronomi och astrofysik; astronomi; Astronomy;

    Abstract : Stellar chemical abundances provide astronomers with vital information about the production of chemical elements. Some stars preserve the composition of the environment in which they were born on their surfaces. READ MORE

  7. 5. Observations and analysis of water in molecular outflows and shocks

    Author : Per Bjerkeli; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; interstellar medium; molecules; jets and outflows; pre-main-sequence; stars; supernova remnants;

    Abstract : This thesis describes observations and analysis of molecular outflows from young stellar objects. The observations using the Odin satellite are described in Paper I, where a non-LTE radiative transfer code has been used to estimate the ortho-water abundance in seven molecular outflows and one super-nova remnant. READ MORE