Dielectronic recombination of Co-like tantalum

{Ab initio }calculation of the total dielectronic recombination (DR) rate coefficient from the ground state of Co-like tantalum is performed using the relativistic distorted-wave approximation with configuration interaction. The contributions to the total DR rate coefficients are explicitly calculated from the complexes of Ni-like tantalum: $3s^23p^63d_{3 / 2}^3 3d_{5 / 2}^6 {n}'{l}'$, $3s^23p^53d^{10}{n}'{l}'$, $3s3p^63d^{10}{n}'{l}'$, $3s^23p^63d^84l{n}'{l}'$, $3s^23p^53d^94l{n}'{l}'$ and $3s3p^63d^94l{n}'{l}'$ with ${n}' \le 25$, and $3s^23p^63d^85l{n}'{l}'$ with ${n}' \le 9$. The ${l}'$ and ${n}'$ dependences of partial DR rate coefficients are investigated. The contributions from higher ${n}'$complexes are evaluated by a level-by-level extrapolation method. The total DR rate coefficients mainly come from the complex series $3s^23p^63d^84l{n}'{l}'$, $3s^23p^53d^94l{n}'{l}'$ and are fitted to an empirical formula with high accuracy. Comparison of the present results with those of other works shows that the previously published data underestimate significantly the DR rates of Co-like tantalum.