2D structure at ﹩t=11250\,{\omega }_{\mathrm{pe}}^{-1}\approx 0.75\,{t}_{{\rm{A}}}﹩ from a representative low-﹩{\beta }_{{\rm{i}}}﹩ simulation (A[0] in Table 1) with ﹩{\beta }_{{\rm{i}}}=0.0078﹩, ﹩{\sigma }_{w}=0.1﹩, ﹩{T}_{{\rm{e}}}/{T}_{{\rm{i}}}=0.1﹩, and ﹩{m}_{{\rm{i}}}/{m}_{{\rm{e}}}=25﹩. We present 2D plots of (a) particle density in units of the upstream initial value, ﹩n/{n}_{0}﹩, with overplotted magnetic field lines; (b) dimensionless electron temperature, ﹩{\theta }_{{\rm{e}}};﹩ (c) logarithm of the magnetic energy fraction, ﹩{\varepsilon }_{B}={B}_{0}^{2}/8\pi {n}_{0}{m}_{{\rm{i}}}{c}^{2};﹩ (d) inflow velocity, in units of Alfvén speed ﹩{v}_{\mathrm{in}}/{v}_{{\rm{A}}}={\boldsymbol{v}}\cdot \hat{{\boldsymbol{y}}}/{v}_{{\rm{A}}};﹩ and (e) outflow velocity, in units of Alfvén speed ﹩{v}_{\mathrm{out}}/{v}_{{\rm{A}}}={\boldsymbol{v}}\cdot \hat{{\boldsymbol{x}}}/{v}_{{\rm{A}}}﹩. We show the full extent of the domain in the x direction (﹩{L}_{x}=4318c/{\omega }_{\mathrm{pe}}﹩) and only a small fraction of the box close to the current sheet in the y direction. The primary island, which contains the particles initialized in the current sheet, can be seen at the boundaries (﹩x=\pm 2200c/{\omega }_{\mathrm{pe}}﹩). As shown in panel (a), the density reaches ﹩n/{n}_{0}\approx 2.3﹩ in the bulk of the outflow, with sharp increases up to ﹩n/{n}_{0}\approx 5﹩ in the core of secondary islands (e.g., at ﹩x=-1000c/{\omega }_{\mathrm{pe}}﹩ and ﹩x=300\,c/{\omega }_{\mathrm{pe}}﹩). The primary island has a high density throughout its interior, ﹩n/{n}_{0}\approx 5.﹩ Similarly, the temperature (panel (b)) is uniform, ﹩{\theta }_{{\rm{e}}}\approx 0.1﹩, in the bulk of the outflow, with spikes up to ﹩{\theta }_{{\rm{e}}}\approx 0.25﹩ at the center of secondary islands. The primary island has a temperature ﹩{\theta }_{{\rm{e}}}\approx 0.15﹩ throughout its interior. In panel (c), we show that the magnetic energy fraction ﹩{\varepsilon }_{B}﹩ is extremely small in the outflow, ﹩{\varepsilon }_{B}\lesssim 0.01﹩. The inflow velocity in panel (d) is a fraction of the Alfvén limit ﹩| {v}_{\mathrm{in}}| /{v}_{{\rm{A}}}\approx 0.08﹩, and the outflow velocity in panel (e) approaches the Alfvén limit, ﹩| {v}_{\mathrm{out}}| /{v}_{{\rm{A}}}\approx 1.﹩