Light-quark mass dependence of the Λ(1405) resonance

We present the light-quark mass dependence of the Λ(1405) resonance at leading order in a renormalizable framework of covariant chiral effective field theory. The meson-baryon scattering amplitudes, which are obtained by solving the scattering equation within time-ordered perturbation theory, follow the quark mass trajectory of the Coordinated Lattice Simulations consortium. At Mπ≈200 MeV and MK≈487 MeV, our parameter-free prediction of Λ(1405) poles is consistent with the recent lattice results of BaSc Collaboration Phys. Rev. Lett. 132, 051901 (2024). Varying the pion mass from 135 MeV to 400 MeV, we present the evolution of double-pole positions of Λ(1405): the higher pole remains a resonance around the K¯N threshold; whereas the lower pole undergoes a transition from resonance to a virtual state, and ultimately to a bound state of the πΣ system, which could be verified by the forthcoming lattice QCD simulations.