Search for dissertations about: "Low mass stars"

Showing result 1 - 5 of 41 swedish dissertations containing the words Low mass stars.

  2. 1. Mass Loss of Evolved Stars : Improving Mass-Loss Rates and Distances

    Author : Miora Andriantsaralaza; Paul Barklem; Elvire De Beck; Susanne Höfner; Jacco van Loon; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; AGB stars; Mass loss; Distance; Circumstellar matter; Radio interferometry; Stellar evolution; Fysik med inriktning mot astrofysik; Physics with specialization in Astrophysics;

    Abstract : In the final stages of their lives, low to intermediate-mass stars enter the Asymptotic Giant Branch (AGB) phase, where they experience significant mass loss through dusty stellar winds. This mass loss is pivotal, not only for the chemical enrichment of the interstellar medium, setting the stage for new stars and planets to form, but also in dictating the evolution and the ultimate fate of the stars themselves. READ MORE

  4. 2. Solar Type Stars as Calibrators : A Photometric and Spectroscopic Study on the Atmospheric Properties of Late-type Stars

    Author : Anna Önehag; Ulrike Heiter; Andreas Korn; Bengt Gustafsson; Frank Grundahl; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; stars: atmospheres; stars: late-type; techniques: photometric; stars: abundances; techniques: spectroscopic; Astronomy; Astronomi;

    Abstract : Detailed knowledge of solar-type stars is essential in the understanding of the evolutionary past, presence and future of the Sun as well as the formation of its planetary system. Moreover, solar-type stars are of key significance for the study of the evolution of the Galaxy. The ages of solar-type stars map the full galactic evolution. READ MORE

  5. 3. The faintest stars : A study of white, red and brown dwarfs

    Author : Leif Festin; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Astronomy; brown dwarfs; white dwarfs; M dwarf; low luminosity; luminosity function; mass function; Pleiades; Astronomi; Astronomy and astrophysics; Astronomi och astrofysik; astronomi; Astronomy;

    Abstract : The local space density of the faintest stars, including M dwarfs, white dwarfs and brown dwarfs has been studied by two different methods.By using dark nebulae as opaque outer screens, the luminosity functions of M dwarfs and white dwarfs were studied as volume-limited and dynamically unbiassed foreground samples. READ MORE

  6. 4. Charting Circumstellar Chemistry of Carbon-rich AGB Stars

    Author : Ramlal Unnikrishnan Nair; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; submillimeter: stars; astrochemistry; stars: mass-loss; circumstellar matter; stars: winds; outflows; Stars: AGB and post-AGB;

    Abstract : Stars of low to intermediate initial masses (0.8 - 8 M⊙) enter the asymptotic giant branch (AGB) phase during their late evolution. READ MORE

  7. 5. 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