Measurement of 139La(n,gamma) Cross Section at n_TOF

The capture cross section of the 139La has been measured relative to 197Au standard at n_TOF. We provide here a short description of the experimental apparatus and of the data analysis procedures. The extracted resonance parameters allow to calculate the fundamental nuclear quantities such as average spacing 1=0 = 268 ± 22 eV, 1=1 < 250 eV neutron strength functions S0 = (0.79 ± 0.03)×10-4, and S1 = (0.73 ± 0.05)×10-4 and the Maxwellian-averaged capture cross section (MACS). The MACS is particularly useful for the determination of the abundance synthesized by the main component of the s process. © 2006 American Institute of Physics.JRC.D.5-Neutron physic