Maps of N_e determinedfrom [S II] (left panel) and [Cl III] (right panel). The contours correspond to the observed log F(H β) image shownin Fig. 3 (left panel), with contours set at log₁₀ F(H β) surface brightness (ergs cm⁻² s⁻¹ arcsec⁻²) from −15.0 to −11.8 in steps of +0.4. The electrondensities for collisional de-excitation of the [S II] and [Cl III] ²D_3∕2 levels for these diagnostics are 3.1 × 10³ and 2.4 × 10⁴ cm⁻³ at 10⁴ K, respectively. The simple means on the signal-to-error value over the two N_e maps are 6 and 4, respectively.