Atomic transition probabilities for Tm I and Tm II

Abstract

Atomic transition probabilities for 376 spectral lines of neutral thulium and for 146 spectral lines of singly ionized thulium are reported. Branching fractions, measured with the 1.0-m Fourier-transform spectrometer at the National Solar Observatory on Kitt Peak, Tucson, Arizona, are combined with recently published radiative lifetimes, measured with time-resolved laser-induced fluorescence on a slow atomic beam, to determine these transition probabilities. Typical uncertainties are less than or equal to ±10%.