Speaker
Evangelia Ntormousi
(SAp/CEA Saclay)
Description
Recent observational results have shown that local interstellar filaments follow a thickness distribution which is surprisingly narrowly peaked at 0.1 pc for a wide range of column densities. This fact is pertinent to the study of interstellar gases as a fingerprint of the physical mechanisms acting on that scale.
But what can create structure of a characteristic size when both gravity and turbulence are scale-free?
In this presentation we will show results of high-resolution, three-dimensional, non-ideal MHD simulations of the multi-phase ISM, performed with the AMR code RAMSES. Our detailed analysis of the filamentary structure emerging from these simulations shows that ambipolar diffusion is an excellent candidate for setting the typical thickness of the dense ISM filaments.
In this paradigm-changing picture, dense filaments are not seen as a transient feature of ISM turbulence, but rather identified as the diffusive end of the turbulent cascade. This interpretation can have important implications in our understanding of not only the dynamical behavior of the ISM as a whole, but also of the initial conditions for star formation.
Author
Evangelia Ntormousi
(SAp/CEA Saclay)