Speaker
Giannandrea Inchingolo
Description
See the full Abstract at http://ocs.ciemat.es/EPS2018ABS/pdf/O4.403.pdf
Fully kinetic large scale simulations of the collisionless Magnetorotational
Instability
G. Inchingolo1,2 , T. Grismayer1 , N. F. Loureiro2 , R. A. Fonseca1,3 , L. O. Silva1
1 GoLP/Instituto de Plasmas e Fusao Nuclear, Instituto Superior Tecnico,
Universidade de Lisboa, Lisbon, Portugal
2 Plasma Science and Fusion Center, MIT, Cambridge, USA
3 Instituto Universitário de Lisboa (ISCTE-IUL), Lisbon, Portugal
The magnetorotational instability (MRI) is a crucial mechanism of angular momentum trans-
port in a variety of astrophysical scenarios, as accretion disks nearness neutron stars and black
holes. The MRI has been widely studied using MHD models and simulations, in order to un-
derstand the behaviour of astrophysical fluids in a state of differential rotation. In radiatively
inefficient accretion flow models for accretion onto compact objects, the accretion proceeds via
a hot, low-density plasma with the proton temperature larger than the electron temperature. In
order to maintain such a two-temperature flow, the typical collision rate must be much smaller
than the accretion rate. This suggests that the standard MHD approach for the description of
the dynamics of such accretion disks may be insufficient, and a kinetic description is required
instead.
Leveraging on the recent result obtained in 2D pair plasma configuration [1], we intend to
present our recent results of the analysis of collisionless MRI in electron-ion plasma. Increasing
the mass ratio of our simulations, we will show the differences between electron-ion plasma
and pair plasma in 2D turbulence, induced consistently during the saturation regime of the
MRI. In particular, we will show the influence of micro-scale (both electron and ion scales)
instabilities in the evolution of collisionless MRI and how these instabilities affect the activation
of a turbulent motion during the saturation of the MRI.
References
[1] G. Inchingolo, et al., Submitted to The Astrophys. Jour.
[2] S. A. Balbus, J. F. Hawley, The Astrophys. Jour., 376, 214 (1991)
[3] S. J. Squire, et al., Jour. of Plasma Phys., 83, 6 (2017)
[4] M. W. Kunz, et al., Phys. Rev. Lett., 117, 235101 (2016)
[5] M. Hoshino, The Astrophys. Jour., 733, 118 (2013)
[6] M. A. Riquelme, et al., The Astrophys. Jour. 755, 50 (2012)
[7] M. A. Riquelme, et al., The Astrophys. Jour. 800, 1 (2015)
