Revised energy levels and hyperfine structure constants of Ta I

A wave number calibrated Fourier transform spectrum, extending from the UV-region (211 nm) to the infrared region (4.6 µm), was used to determine with high accuracy the center of gravity wave numbers of hyperfine structure - resolved Ta I spectral lines. The majority of the hyperfine constants, necessary for this step, were known from literature. For some energy levels, the constants were determined in this work. From the obtained wave numbers of altogether 3249 spectral lines, we calculated in a global fit procedure the energies of 216 levels with even parity and 290 levels with odd parity. A comparison between our results and (partially unpublished) energy values from the literature is given, as well as a compilation of available hyperfine structure constants.