Photoionization cross sections of the excited states of iron, chromium and vanadium

This paper reports the results that the resonance enhanced multiphoton ionization (REMPI) of the iron, chromium and vanadium atoms of the transition metals in the range of 278∼288 nm, 335∼361 nm and 300∼310 nm respectively. Laser ablation coupled with the molecular beam are used to produce free atoms in the experiment and the ions were detected using the time of flight mass spectrometer. According to the dependencies between resonance ionization ion signal and the power of the detection laser, we can obtain photoionization cross section value of the atomic excited state. (authors)