Comparison of reactions for the production of Db258,257: 208Pb(51V,xn) and 209Bi(50Ti,xn)

Excitation functions for the 1n and 2n exit channels of the Pb-208(V-51, xn)(259-x)Db 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 Bi-209(Ti-50, n)(258)Db 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.