Seminario a cargo del postdoc Severo Ochoa J. Vranjes
El investigador postdoctoral Jovo Vranjes, recientemente incorporado al IAC, impartirá un seminario regular el 19 de febrero de 2015 titulado Collisional phenomena in the lower solar atmosphere (Fenómenos colisionales en la baja atmósfera solar).
Inicio: 19 Feb, 2015 - 10:30
Finalización: 19 Feb, 2015 - 12:00
Lugar: Aula, Sede Central del IAC, Tenerife.
Organiza: Instituto de Astrofísica de Canarias
Resumen:
The lower solar atmosphere is very weakly ionized, and by conductivity it is comparable to the sea water. The collisional frequency for electrons and ions can be over 1010 Hz and 109 Hz, respectively. This implies that particles may not be magnetized and are thus unaffected by the magnetic field. In this talk I shall present accurate collision cross sections and collision frequencies for electrons, protons and hydrogen atoms, and the corresponding transport coefficients for layers with both unmagnetized and magnetized particles. The cross sections include many essential effects like charge exchange, quantum-mechanical in-distinguishability at low energies, polarization of neutral atoms by external charges, and dependence on energy of colliding particles. The effects of collisions on Alfven waves will also be discussed
