Behavior of the outer evection resonance for equal masses of the Trojan pair. Panel a: topology of m₁ at a distance of a₁ = a₂ = 0.39 au (5.88 × 10⁷ km), and assuming a periastron difference Δϖ = 60° (i.e., atthe ACR solution). Panel b: same as panel a, but for a periastron difference Δ ϖ = 70°. Panel c: distance from the planet at which the evection resonance appears (full line), and the angle of the resonance center (dashed line) as a function of the mass ratio.