Radiative lifetimes of odd-parity levels in Nb I

Radiative lifetimes are reported for 37 odd-parity energy levels of neutral niobium (Nb I), out of which 33 have been measured for the first time. The levels belong to electronic configurations 4d³5s5p and 4d⁴5p between 18,790 and 35,730 cm⁻¹. The time-resolved laser-induced fluorescence spectroscopy technique was employed. The Nb atoms were generated in a free-jet by laser vaporization of niobium metal. Lifetime values reported in this work fall in the range 12–340 ns and are accurate to ±10%. - Highlights: • Lifetime in Nb I using time-resolved laser-induced fluorescence in free-jet. • Radiative lifetimes reported in 37 odd-parity energy levels of Nb I. • Lifetimes for 33 energy levels reported for the first time