  In a recent study of the Lambda(1405), the suppression of the strange-quark
contribution to the magnetic form factor was interpreted as the discovery of a
dominant antikaon-nucleon composition for this low-lying state. We confirm this
result by calculating the light u- and d-quark contributions to the
Lambda(1405) magnetic form factor in lattice QCD in order to determine the
extent to which their contributions support this exotic molecular description.
Drawing on the recent graded-symmetry approach for the flavor-singlet
components of the Lambda(1405), the separation of connected and disconnected
contributions is performed in both the flavor-octet and singlet
representations. The relationship between light-quark contributions to the
Lambda(1405) magnetic form factor and the connected contributions of the
nucleon magnetic form factors is established and compared with lattice
calculations of the same quantities, confirming the KN molecular structure of
the Lambda(1405) in lattice QCD.
