Research activities 1993-1999

I am a Ph.D. from the Université Pierre et Marie Curie (Paris VI) and DASOP (Meudon observatory) currently working with a CNES postdoctoral fellowship back in DASOP/LPSH after one year at the Space Sciences Laboratory (UC Berkeley). My research interests are solar and interplanetary medium physics.

More precisely, my topic is the injection and propagation of solar particles in the interplanetary medium.

During my Ph.D. work I have shown thanks to Ulysses' instruments that some solar electron beams (injected during solar flares) could propagate inside special plasma structures called "propagation channels" up to very large distances. These structures are rooted on solar surface and were detected by Ulysses up to 4 AU (4 times the Sun-Earth distance). Their length and transverse dimensions make them look like long spaghettis rooted on solar surface and extending in the heliosphere.
During my postdoctoral work, I have identified some of those "channels" near 1 AU (Earth orbit) and studied their plasma and magnetic field properties with WIND's instruments.  They were found to be comparable to those found by Ulysses at larger distances.

The discovery of such spaghettis-like structures in the heliosphere maintaining there cohesion and properties so far away from the Sun has implication on the structure of this medium as the direct connection of some portion of the heliosphere to solar surface implies that solar surface phenomena and inhomogeneities may have a direct influence even far away from the Sun. Other questions posed by theses "channels" are to explain the mechanisms responsible for their stabilization on such large distances and to find the solar corona or surface features that characterize them at their origin on the Sun. I am currently working on the theoretical aspect of those problems and will extend it to fine structure solar observations. There are various example of observations or theoretical implication of spaghetti-like structures in other domains of Astrophysics.

Here are my scientific publications for more details and my Ph.D. thesis (in french).
Go here to find a presentation some of the more striking results obtained by the Ulysses HI-SCALE team (still in French...).