NEUTRON-CAPTURE OF MG-26 AT THERMONUCLEAR ENERGIES

The neutron capture cross section of Mg-26 was measured relative to th e known gold cross section at thermonuclear energies using the fast cy clic activation technique. The experiment was performed at the 3.75 MV Van-de-Graaff accelerator, Forschungszentrum Karlsruhe. The experimen tal capture cross section is the sum of resonant and direct contributi ons. For the resonance at E-n,E-lab = 220 keV our new results are in d isagreement with the data from Weigmann, Macklin, and Harvey [Phys. Re v. C 14, 1328 (1976)]. An improved Maxwellian averaged capture cross s ection is derived from the new experimental data taking into account s and p-wave capture and resonant contributions. The properties of so-ca lled potential resonances which influence the p-wave neutron capture o f Mg-26 are discussed in detail.