Sökning: "stellar spectroscopy"

Visar resultat 1 - 5 av 26 uppsatser innehållade orden stellar spectroscopy.

1. 1. Wavelength-dependent limb darkeningin the analysis oftransit spectroscopy of exoplanets

   L3-uppsats, Uppsala universitet/Institutionen för fysik och astronomi

   Författare :Alberto García Ribas; [2023]
   Nyckelord :;

   Sammanfattning : Limb darkening, an optical effect characteristic of stars, where the limb (edge) seemsto be darker than the centre of the stellar body; plays an important role in our under-standing of exoplanetary transits, as it is fundamental for developing light curve modelsthat can help to undercover extrasolar companions. To recover atmospheric featuresfrom exoplanets, a principal component analysis method is typically used. LÄS MER

3. 2. Finding new members of the VelHel-4 stream

   Kandidat-uppsats, KTH/Skolan för teknikvetenskap (SCI)

   Författare :Lucas Johansson; [2023]
   Nyckelord :Galactic Archaeology; Milky Way; Stellar Streams; Streams; Stellar Halo; Stars; Globular Cluster; Astronomy; Astrophysics; Gaia; Chemical Abundance; Spectroscopy;

   Sammanfattning : According to the paradigm of lambda-CDM cosmology, the stellar halo ofour Galaxy has been built-up over time through the accretion of other galaxiesand star clusters. The remnants of some of these are still observable today asstellar streams, but are typically very faint and difficult to resolve amidst the farmore numerous foreground Milky Way stars. LÄS MER

4. 3. Simulations of the Tenuous Upper Atmospheres of Exoplanets

   Master-uppsats, Lunds universitet/Astrofysik; Lunds universitet/Fysiska institutionen

   Författare :Lucian Spitzner; [2023]
   Nyckelord :astronomy; astrophyics; exoplanets; transmission spectroscopy; magnetic fields; atmospheres; ions; Physics and Astronomy;

   Sammanfattning : Over the last decade, the interest in research on extraterrestrial planets has expanded dramatically. With the number of confirmed exoplanets having increased tenfold over the last ten years, we now know that many different types of exoplanets exist. LÄS MER

5. 4. Spectroscopic model characterisation of hot exoplanet atmospheres

   Master-uppsats, Lunds universitet/Astronomi - Genomgår omorganisation; Lunds universitet/Fysiska institutionen

   Författare :Elin Sandvik; [2022]
   Nyckelord :Transit method; Transmission spectroscopy; Exoplanets; Hot Jupiter; Modelling; Physics and Astronomy;

   Sammanfattning : Hot Jupiters are gas giants under intense stellar radiation with short orbital periods of only a few days. Due to their large radii, hot temperatures, and large scale heights, hot Jupiters can be observationally characterised in detail through spectroscopy over an entire orbital phase. LÄS MER

7. 5. An Infrared Stellar Thermometer

   Kandidat-uppsats, Lunds universitet/Astronomi - Genomgår omorganisation

   Författare :Ieva Puspure; [2021]
   Nyckelord :Infrared Spectroscopy; Infrared; Red giants; Stellar Temperature; Spectroscopy; Physics and Astronomy;

   Sammanfattning : Infrared (IR) spectroscopy has many advantages over optical, one of which is allowing us to see through intergalactic dust, letting us probe deeper into space and dust-dense regions such as galactic centers. However the investigating the IR spectral range is a relatively new field, owing to recent developments in detector technology, and stellar parameter determination in IR is not well researched. LÄS MER