On the Structure of the Lambda 1405

For almost 50 years the structure of the Λ(1405) resonance has been a mystery. Recently, a new lattice QCD simulation showing that its strange magnetic form factor vanishes, together with a comprehensive Hamiltonian analysis of the lattice QCD energy levels, has unambiguously estab-lished that the structure is dominated by a bound anti-kaon–nucleon component [1]. Here we present supplementary information for Ref. [1] including a presentation of the relevant Hamilto-nian effective field theory and an illustration of the volume dependence of the results and their connection to the infinite volume limit of Nature