Top: volume rendering of the current density j (compensated by r) (grayscale), overlaid with the dissipation rate j · E (compensated by r²) (red), with field lines in white showing the flux tube. Bottom: 1D profile of σ/σ₀ (dark blue), n/n_GJ,* (teal), B_xy/B_* (red), and B_z/B_* (yellow) along a line ℓ piercing through the current sheet (see light-green arrow in the top panel). The reconnecting field B_z begins to reverse when σ ∼ σ₀, while the guide field B_xy remains roughly constant.