New energy levels of atomic niobium (Nb I) discovered by laser-spectroscopic investigations

Abstract

We report the discovery of 9 previously unknown energy levels of the atomic niobium, all having even parity. Two levels have energies below 19,500 cm(-1) and angular momentum J=3/2, while the energies of the others are located between 39,700 and 43,420 cm(-1). The levels were discovered by laser excitation of several unclassified spectral lines in the wavelength range between 554 nm and 650 nm and detection of laser-induced fluorescence with a monochromator. (C) 2018 Elsevier Ltd. All rights reserved.