JEFF-3.1.1 Evaluated Data: neutron data

Released in 2009, the JEFF-3.1.1 library is a revision of JEFF-3.1, providing corrected and updated neutron cross-section evaluations for more than 400 isotopes. The modifications and improvements introduced in this version are documented in JEFF Report 22, ensuring traceability and transparency of the changes. JEFF-3.1.1 has been benchmarked against a wide range of integral experiments and has been applied internationally in reactor physics, shielding, fuel cycle analysis, and criticality safety studies.