Sökning: "cosmic chemistry"

Visar resultat 6 - 10 av 22 avhandlingar innehållade orden cosmic chemistry.

1. 6. Solar Wind and Geomagnetic Activity - Predictions Using Neural Networks

   Författare :Hans Gleisner; Astronomi - Genomgår omorganisation; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Geophysics; kosmisk kemi; rymdvetenskap; magnetosphere; solar wind; space weather; geomagnetic activity; geomagnetism; ring current; auroral electrojet; neural networks; forecasting; Astronomy; space research; Astronomi; cosmic chemistry; physical oceanography; meteorology; Geofysik; fysisk oceanografi; meteorologi; Fysicumarkivet A:2000:Gleisner;

   Sammanfattning : This thesis shows how artificial neural networks (ANNs) can be applied to predict geomagnetic activity from solar-wind data. It introduces and summarizes five papers where development of ANN models are reported, and where predictions of geomagnetic activity are discussed. LÄS MER

3. 7. Extremely Large Telescopes Optical Design and Wavefront Correction

   Författare :Alexander Gontcharov; Astronomi - Genomgår omorganisation; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Astronomy; akustik; optik; Adaptive Optics; Extremely Large Telescopes; optical design methods; wavefront correction methods.; Electromagnetism; optics; Elektromagnetism; acoustics; space research; cosmic chemistry; Astronomi; rymdvetenskap; kosmisk kemi;

   Sammanfattning : An overview of the state of art within optical design of large astronomical telescopes is given. Recent advances within the field are presented. The importance of new computer-controlled mirror-polishing methods is emphasized. LÄS MER

4. 8. Anomalous Spectral Lines in Space and Laboratory Plasmas - Studies with HST and CRYRING

   Författare :Henrik Hartman; Astronomi - Genomgår omorganisation; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; magnetic resonance; supraconductors; magnetic and optical properties; electrical; Condensed matter:electronic structure; strontium; titanium; CRYRING; iron; STIS; metastable levels; HST; RR Telesopii; Eta Carinae; line identification; fluorescence; forbidden lines; Atomic Spectroscopy; lifetime measurements; Astronomy; Astronomi; rymdvetenskap; cosmic chemistry; space research; spektroskopi; supraledare; magnetiska och optiska ; egenskaper elektriska; Kondenserade materiens egenskaper:elektronstruktur; magnetisk resonans; relaxation; spectroscopy; kosmisk kemi; Fysicumarkivet A:2003:Hartman;

   Sammanfattning : Eta Carinae is one of the most massive and luminous stars in the Galaxy. A huge bipolar nebula and an equatorial disk give the object a characteristic shape. Close to the star there are gas clouds, which emit intriguing emission line spectra. LÄS MER

5. 9. Galactic Structure Revealed by Space Astrometry

   Författare :Johan Holmberg; Astronomi - Genomgår omorganisation; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Astronomi; cosmic chemistry; Galactic structure; Milky Way Galaxy; Galactic kinematics and dynamics; Galactic chemical evolution; moving groups; solar neighbourhood; dark matter; astrometry; Hipparcos; space research; Astronomy; rymdvetenskap; kosmisk kemi; Space technology; Rymdteknik; Fysicumarkivet A:2001:Holmberg;

   Sammanfattning : This work demonstrates how the structure of our Galaxy, the Milky Way, can be unveiled with the use of space astrometry. It consists of two parts, of which the first is a brief introduction to the fields of Galactic structure, covering the Galaxy's stellar constituents, how the Galaxy was formed and how it has evolved over time, both chemically and kinematically. LÄS MER

7. 10. Advances in Stellar Astrophysics from Laboratory Spectroscopy

   Författare :Stefan Ivarsson; Atomfysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Astronomy; iridium; osmium; uranium; oscillator strengths; Spectroscopy; term analysis; line profiles; line structure; astrophysics; Sun; Chi Lupi; 17 Comae A; chemically peculiar; praseodymium; stars; space research; cosmic chemistry; Astronomi; rymdvetenskap; kosmisk kemi; Fysicumarkivet A:2004:Ivarsson;

   Sammanfattning : Investigation of astrophysical plasmas, such as stellar atmospheres, require both knowledge of atomic structure and data. We present laboratory instruments, techniques and tools for acquisition of the data required to derive important atomic parameters such as, wavelengths, oscillator strengths and line profiles. LÄS MER