“That is where my dearest and brightest dreams have ranged — to hear for the duration of a heartbeat the universe and the totality of life in its mysterious, innate harmony.” Hermann Hesse

Collisional models of debris discs

The main outcome of my PhD was the creation of the new code LIDT-DD (Kral et al. 2013) to model debris discs in all their complexity. LIDT-DD is the first (and so far unique) code in its ability to model both the dynamical and collisional evolution of solids in a debris disc, taking into account the radiation pressure on the smallest grains. It is coupled to the radiative transfer code GRaTer (Augereau et al. 1999, Augereau & Beust 2006) to compute synthetic images or SEDs of the modelled scenarios in order to be able to compare to observations of these discs. See the giant impact section to see one application of the code. Many more are coming!

 

If you want to lead a project that would need LIDT-DD, I'm happy to be contacted and explore the idea with you and then to provide LIDT-DD for you to use. Just contact me for more info.

 

Amongst the most sophisticated debris disc models that have been developed to date is also the DyCoSS (Thebault 2012, Thebault, Kral, Ertel 2012, Thebault, Kral, Augereau 2014) code (see also Levison et al. 2012; Nesvold et al. 2013). Both LIDT-DD and DyCoSS can follow the collisions at the same time as the dynamics. However, they are different in their principles and limitations. DyCoSS is restricted to steady-state situations under the influence of a single planet and collisions are fully destructive. LIDT-DD overcomes these limitations but the price to pay is a slower computational time.

DyCoSS can study very fine spatial structures and has been used to study debris discs around binaries (Thebault 2012) or discs with an embedded or exterior planet (Thebault et al. 2012; Lagrange et al. 2012). Owing to the presence of the planet, resonant structures develop as well as a density gap at the planet location. According to previous N-body non-collisional simulations, the density gap (which corresponds to the chaotic zone of the planet) should be totally devoid of dust. However, this new generation code is able to show that it is more complicated, as small grains produced in the inner disc that are on eccentric orbits, actually fill up the chaotic zone. Many more results were produced by the DyCoSS and LIDT-DD codes that I let you discover directly in the related papers.