Neutron resonance spectroscopy: Ta

Results of high resolution neutron time of flight spectroscopy on natural tantalum (99. 988% ^181Ta, I^=7{2^+}) are presented for l=0 resonances to 2025 eV. Values of E and g₍^0 are presented for 431 resonances, in addition to the three resonances below 15 eV. A Bayes analysis suggests that no p wave levels have been included. The analysis used a multilevel Breit-Wigner shape fitting to the measured transmission curves for three different sample thicknesses. Doppler broadening and potential-resonance interference effects were included, plus some simulation of the experimental resolution effects. The analysis gives 〈S〉= (4. 170. 04) eV for the mean level spacing, and 10^4S₀= (1. 680. 11) for the l=0 strength function. NUCLEAR REACTIONS ^181Ta (n, total), E=15 to 2030 eV; deduced resonance E, g₍^0, 〈S〉, S₀.