Sökning: "particle astrophysics"

Visar resultat 11 - 15 av 65 avhandlingar innehållade orden particle astrophysics.

1. 11. Numerical modelling of ENAs from stellar wind interactions

   Författare :Andreas Ekenbäck; Mats Holmström; Michael R. Collier; Institutet för rymdfysik (IRF); []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Space physics; Space technology; Astrophysics; Space engineering; Rymdteknik;

   Sammanfattning : Energetic neutral atoms (ENAs) are produced whenever a stellar wind encounters a neutral atmosphere. If a stellar wind proton comes sufficiently close to a neutral a charge-exchange reaction may take place, transforming the proton into an ENA. LÄS MER

3. 12. Studies of cosmic rays with the anticoincidence system of the PAMELA satellite experiment

   Författare :Silvio Orsi; Mark Pearce; Martin Pohl; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; astrophysics; astroparticle physics; antimatter; organic scintillators; cosmic rays; trapped particles; Astroparticle physics; Astropartikelfysik;

   Sammanfattning : PAMELA is a satellite-borne experiment designed to study the charged component of the cosmic radiation of galactic, solar and trapped nature. The main scientific objective is the study of the antimatter component of cosmic rays over a wide range of energies (antiprotons: 80 MeV–190 GeV, positrons: 50 MeV–270 GeV). LÄS MER

4. 13. Dark Matter in the Solar System, Galaxy, and Beyond

   Författare :Axel Widmark; Jens Jasche; Malcolm Fairbairn; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; dark matter: phenomenology; dark matter: indirect detection; dark matter: particle nature; Galactic dynamics; Galactic composition; Theoretical Physics; teoretisk fysik;

   Sammanfattning : There is evidence that dark matter constitutes a majority of the Universe's matter content. Yet, we are ignorant about its nature. Understanding dark matter requires new physics, possibly in the form of a new species of fundamental particles. LÄS MER

5. 14. Magnetic Reconnection in Space Plasmas : Cluster Spacecraft Observations

   Författare :Alessandro Retinò; Mats André; Andris Vaivads; Bengt U. Ö. Sonnerup; Uppsala universitet; []
   Nyckelord :Space and plasma physics; space physics; plasma astrophysics; plasma physics; transport processes; boundary layers; magnetic reconnection; turbulence; particle acceleration; solar system; magnetospheres; Rymd- och plasmafysik;

   Sammanfattning : Magnetic reconnection is a universal process occurring at boundaries between magnetized plasmas, where changes in the topology of the magnetic field lead to the transport of charged particles across the boundaries and to the conversion of electromagnetic energy into kinetic and thermal energy of the particles. Reconnection occurs in laboratory plasmas, in solar system plasmas and it is considered to play a key role in many other space environments such as magnetized stars and accretion disks around stars and planets under formation. LÄS MER

7. 15. 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