Scaling of the growth rate of magnetic islands in the heliosheath
arXiv:1205.1865 · doi:10.1088/2041-8205/750/2/L30
Abstract
Current sheets thinner than the ion inertial length are unstable to the tearing instability and will develop magnetic islands that grow due to magnetic reconnection. We investigate whether the growth of magnetic islands in a current sheet can continue indefinitely, or in the case of the heliosheath until reaching a neighboring current sheet, and at what rate the islands grow. We investigate the development and growth of magnetic islands using a particle-in-cell code, starting from particle noise. Performing a scaling of the growth of magnetic islands versus the system size, we find that the growth rate is independent of the system size up to the largest simulation we were able to complete. The islands are able to continue growing as long as they merge with each other and maintain a high aspect ratio. Otherwise there is not enough magnetic tension to sustain reconnection. When applied to the sectored magnetic fields in the heliosheath, we show that the islands can continue growing until they reach the sector width and do so in much less time than it takes for the islands to convect through the heliosheath.
References in corpus (6)
- Two-scale structure of the electron dissipation region during collisionless magnetic reconnection
- Dissipation of the sectored heliospheric magnetic field near the heliopause: a mechanism for the generation of anomalous cosmic rays
- A catastrophe model for fast magnetic reconnection onset
- Is the magnetic field in the heliosheath laminar or a turbulent bath of bubbles?
- The effects of plasma beta and anisotropy instabilities on the dynamics of reconnecting magnetic fields in the heliosheath
- Three-dimensional simulations of the orientation and structure of reconnection X-lines