We experimentally study the magnetic-dipole 1s22s2p 3P1−3P2 transition in Be-like Ar14+. The wavelength of this transition is known to be sensitive to the quantum electrodynamics effect and has been measured many times by emission spectroscopy using an electron beam ion trap (EBIT). However, there is a significant discrepancy among the previously measured values. Here, we report the first experimental verification of the transition wavelength by laser spectroscopy. The present result is 594.5495(21) nm, which is in reasonable agreement (<1.5σ) with the latest value measured by emission spectroscopy by the Heidelberg EBIT group.
Miya et al. (Wed,) studied this question.