Sökning: "massive stars"

Visar resultat 16 - 20 av 67 avhandlingar innehållade orden massive stars.

1. 16. Magnetic fields and chemical maps of Ap stars from four Stokes parameter observations

   Författare :Naum Rusomarov; Oleg Kochukhov; Nikolai Piskunov; Werner Weiss; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; chemically peculiar stars; magnetic fields; spectropolarimetry; Doppler imaging; stellar atmospheres; Astronomy with specialization in Astrophysics; Astronomi med intiktning mot astrofysik; Astronomy; Astronomi;

   Sammanfattning : Our knowledge of stellar magnetic fields relies almost entirely on circular polarization observations, which has historically limited our understanding of the stellar magnetic field topologies. Recently, it has become possible to obtain phase-resolved high-resolution spectropolarimetric observations in all four Stokes parameters for early-type magnetic stars. LÄS MER

3. 17. Exotic phases of matter in compact stars

   Författare :Fredrik Sandin; Luleå tekniska universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Fysik; Fysik;

   Sammanfattning : This doctoral thesis in physics at Luleå University of Technology is devoted to the phenomenology of compact stars, and theoretical models of their interior. Particle physics has provided fundamental concepts and details needed to develop a description of matter and the evolution of the universe. LÄS MER

4. 18. Magnetic fields around massive protostars as traced by masers and dust emission

   Författare :Daria Dall` Olio; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; magnetic field – stars: formation – stars: massive – masers – dust – polarization – stars: individual: IRAS 18089-1732 – G9.62 0.19;

   Sammanfattning : It is not fully clear how the magnetic field acts during the first stages of star formation. A possible way to clarify its role is to observe the polarized light coming from masers and thermal dust emission. LÄS MER

5. 19. Studies of dark matter in and around stars

   Författare :Sofia Sivertsson; Tommy Ohlsson; Joakim Edsjö; Gianfranco Bertone; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Dark matter; particle astrophysics;

   Sammanfattning : There is by now compelling evidence that most of the matter in the Universe is in the form of dark matter, a form of matter quite different from the matter we experience in every day life. The gravitational effects of this dark matter have been observed in many different ways but its true nature is still unknown. LÄS MER

7. 20. Unveiling a multiscale view of massive star and cluster formation

   Författare :Chi Yan Law; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Star Formation;

   Sammanfattning : Massive stars regulate the physical and chemical evolution of galaxies. Most stars within these galaxies, including massive ones, appear to be born in star clusters and associations. However, many questions remain unanswered about how massive stars and clusters form from the diffuse gas of interstellar space. LÄS MER