Habilitation defended on November 27th, 2013 at the Laboratoire AstroParticule et Cosmologie (APC).

Members of the Jury

• Dr Michel TAGGER (Chairman)
• Prof. Gilles HENRI (Referee)
  
• Prof. Etienne PARIZOT (Referee)
  
• Prof. Christophe SAUTY (Referee)
• Dr Sylvie CABRIT
• Dr Martin LEMOINE
  

The HDR/Habilitation dissertation can be downloaded here (pdf format).

Thèse de doctorat/PhD Thesis

"From MHD astrophysical jet launching to cosmic rays:
The function of magnetic turbulence"

Keywords: High-energy astrophysics - Astroparticules - MHD - Cosmic Rays and UHE neutrinos - High-energy photons (synchrotron X & gamma) - Accretion-Ejection - Kinetic Theory.

PhD thesis defended on June 26th, 2001 at the LAOG (Grenoble - France).

Members of the Jury

• Dr Guy LAVAL (Chairman)
• Prof. John KIRK (Referee)
  
• Prof. Jean HEYVAERTS (Referee)
  
• Dr Michel TAGGER
• Prof. Guy PELLETIER (Advisor)
• Dr Jonathan FERREIRA (Co-advisor)
• Dr Martin LEMOINE
  

File of the PhD Thesis (PDF) in french: THESE.pdf

Summary

The first part of my thesis shows how Keplerian discs can launch MHD jets, under some conditions. The key points of this first part are the adding of viscosity inside the disc and a relevant energy equation, In particular, I have shown both analytically and numerically that the angular momentum transport is constrained by the MHD turbulence properties. I have also shown that one must take into account a relevant energy equation in order to have a more realistic description of jets observed in the Universe. Moreover, some energy turbulent transport mechanisms cannot be described in a simple MHD approach.
In order to better understand the interaction between a turbulent magnetic field and charged particles, I have undertaken a  study dealing with spatial and angular diffusion of hadrons with a chaotic magnetic  field generated by a magnetic turbulence. In this study, it clearly  appears that the spatial diffusion coefficient along the mean magnetic  field extrapolate the results of quasi-linear theory for weakturbulence. At the opposite, in the inertial range, the spatial diffusion coefficient across the mean magnetic field is inconsistent with such a theory. Indeed the spatial diffusion coefficient across the mean magnetic field  has a behaviour that can be interpreted as a chaotic diffusion regime as the one predicted by Rechester & Rosenbluth. Moreover, outside this range, the behaviours of all spatial diffusion coefficients are different of those expected in the framework of quasi-linear theory. At last, it has been found that the Bohm diffusion regime never occurs whatever the magnetic turbulence level.