Comparison of reactions for the production of ^258,257Db: ²⁰⁸Pb(⁵¹V,xn) and ²⁰⁹Bi(⁵⁰Ti,xn)

Excitation functions for the 1n and 2n exit channels of the ²⁰⁸Pb(⁵¹V,xn)^259-xDb reaction were measured. A maximum cross section of the 1n exit channel of 2070_-760⁺¹¹⁰⁰ pb was measured at an excitation energy of 16.0 ± 1.8 MeV. For the 2n exit channel, a maximum cross section of 1660_-370⁺⁴⁵⁰ pb was measured at 22.0 ± 1.8 MeV excitation energy. The 1n excitation function for the ²⁰⁹Bi(⁵⁰Ti,n)²⁵⁸Db reaction was remeasured, resulting in a cross section of 5480_-1370⁺¹⁷³⁰ pb at an excitation energy of 16.0 ± 1.6 MeV, in agreement with previous values [F. P. Heßberger et al., Eur. Phys. J. A 12, 57 (2001)]. Differences in cross section maxima are discussed in terms of the fusion probability below the barrier.