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Two-photon absorption in systems with parity permits access to states that cannot be directly prepared by onephoton absorption.Here we investigate ultrafast inteal conversion (IC) dynamics of furan by using this strategy in combination with femtosecond time-resolved photoelectron imaging.The dark Rydberg S1 and bright valence S2 states are simultaneously excited by two photons of 405 nm,and then ionized by two photons of 800 nm.The IC from S2 to S1 is clearly observed and extracted from the time dependence of the higher photoelectron kinetic energy (PKE) component.More importantly,the inteal conversions to hot S0 from directly-prepared S1 and secondarily-populated S1 are unambiguously identified by the time-dependence of the lower PKE component.The average lifetime of the S2 and S1 states is measured to be 29fs.The inteal conversions of S2 to S1,S1 to hot S0 occur on estimated timescales of 15.4fs and 38 fs,respectively.