Spectrum averaged cross section measurements of lutetium using standard ²⁵²Cf neutron source

The spectrum averaged cross section (SACS) in a standard neutron field is a preferable tool for cross section validation. The presented work uses only neutron standard, i.e., ²⁵²Cf(sf) reaction neutron field, for validation of lutetium threshold cross sections. SACS were inferred from gamma spectrometry derived reaction rates. The SACS which were derived include ¹⁷⁵Lu (n,2n)¹⁷⁴Lu, ¹⁷⁵Lu (n,3n)¹⁷³Lu, ¹⁷⁵Lu (n,p)¹⁷⁵Yb, and ¹⁷⁶Lu (n,n')^176m1Lu reactions. All these reactions SACS were measured for the first time. MCNP6.2 calculations using JEFF-3.3 or ENDF/B-VIII.0 libraries for lutetium cross sections were compared with experimental data. The agreement was found very poor for all reactions under study. Thus there is a need for their improvement. The presented data can be also used for validation of the various theoretical models.