The two Λ(1405) poles from photoproduction data

Abstract

We present results extracting the position of the two Λ(1405) poles from experimental photoproduction data measured recently at different energies in the γp → K+π0Σ0 and γp → K+π±Σ∓ reactions at Jefferson Lab. The analysis is done by means of a chiral dynamics motivated potential but with free parameters, which guarantees analyticity and unitarity in the solutions. With the best result we find the two Λ(1405) poles at about 1352 − 48i MeV and 1419 − 29i MeV.