Figure 3
From: Topology of turbulence within collisionless plasma reconnection
Magnetic field topology within the reconnection region. Panel (a) reproduces the information of Fig. 2a and is used to colour-code specific time intervals: green shading (as in Fig. 2) indicates the time interval in which at least one spacecraft samples the EDR, split into sub-intervals indicated by the dark green, blue and red traces, which are the leading edge of the EDR, the EDR, and the trailing edge of the EDR respectively. Regions before, and after the EDR is encountered are indicated by grey and black time traces respectively. The same colours are used in the lower panels to indicate the time intervals within which the topological invariants are obtained. The lower panels plot the topological invariants for all field deformations R, Q (panel b) and the curl-free field deformations \(R_s,Q_s\) (panel c), respectively. In panel (b) elliptic \(\Delta >0\) (flux ropes) and hyperbolic \(\Delta <0\) are seperated by the magenta line \(\Delta =0\). In panel (c), \(\Delta _s=0\) is the boundary of possible curl-free deformations of magnetic field lines. The magenta line in panel (c) corresponds to triaxial deformations with eigenvalue ratios − 3:− 1:4 (\(R_s<0\)) and 3:1:− 4 (\(R_s>0\)), as found in the strain tensor of a three dimensional hydrodynamic flow28,29.
