The Cross Section Evaluation Working Group (CSEWG) released the ENDF/B-VII.1 library on December 22, 2011. The ENDF/B-VII.1 library is our latest recommended evaluated nuclear data file for use in nuclear science and technology applications, and incorporates advances made in the five years since the release of ENDF/B-VII.0, including: many new evaluation in the neutron sublibrary (423 in all) and over 190 of these contain covariances, new fission product yields and a greatly expanded decay data sublibrary.

Library Summary

Below we show the contents of the ENDF/B-VII.1 library, with ENDF/B-VII.0 and ENDF/B-VI.8 shown for comparison. NSUB stands for the sublibrary number in the ENDF-6 format. Given in the last three columns are the number of materials (isotopes or elements).

No.	NSUB Name	Sublibrary Name	Short	VII.1	VII.0	VI.8
1	0	Photonuclear	g	163	163	-
2	3	Photo-atomic	photo	100	100	100
3	4	Radioactive decay	decay	3817	3838	979
4	5	Spont. fis. yields	s/fpy	9	9	9
5	6	Atomic relaxation	ard	100	100	100
6	10	Neutron	n	423	393	328
7	11	Neutron fis.yields	n/fpy	31	31	31
8	12	Thermal scattering	tsl	21	20	15
9	19	Standards	std	8	8	8
10	113	Electro-atomic	e	100	100	100
11	10010	Proton	p	48	48	35
12	10020	Deuteron	d	5	5	2
13	10030	Triton	t	3	3	1
14	20030	3He	he3	2	2	1

1. The photonuclear sublibrary was carried over unchanged from ENDF/B-VII.0. It contains evaluated cross sections for 163 materials (all isotopes) mostly up to 140 MeV. The sublibrary was supplied by Los Alamos National Laboratory (LANL) and it is largely based on the IAEA-coordinated collaboration completed in 2000.
2. The photo-atomic sublibrary was taken over from ENDF/B-VII.0=ENDF/B-VI.8. It contains data for photons from 10 eV up to 100 GeV interacting with atoms for 100 materials (all elements). The sublibrary was supplied by Lawrence Livermore National Laboratory (LLNL).
3. The decay data sublibrary has been re-evaluated and considerably improved by the Brookhaven National Laboratory (BNL).
4. The spontaneous fission yields were taken over from ENDF/B-VII.0=ENDF/B-VI.8. The data were supplied by LANL.
5. The atomic relaxation sublibrary was taken over from ENDF/B-VII.0=ENDF/B-VI.8. It contains data for 100 materials (all elements) supplied by LLNL.
6. The neutron reaction sublibrary represents the heart of the ENDF/B-VII.1 library. The sublibrary has been updated and extended, it contains 423 materials, including 422 isotopic and 1 elemental evaluation.. Altogether 234 materials have been changed in ENDF/B-VII.1 compared to ENDF/B-VII.0.
7. Neutron fission yields were reevaluated for ²³⁹Pu (fast and 14 MeV) by Los Alamos; others were taken over from ENDF/B-VII.0=ENDF/B-VI.8, having been supplied by LANL.
8. The thermal neutron scattering sublibrary was carried over unchanged from ENDF/B-VII.0. It contains thermal scattering-law data, largely supplied by LANL, with the addition of SiO₂ in ENDF/B-VII.1 from ORNL.
9. The neutron cross section standards sublibrary was carried over from ENDF/B-VII.0 unchanged. Therefore, as for VII.0, the VII.0 standard cross sections were completely adopted by the VII.1 neutron reaction sublibrary except for the thermal cross section for ²³⁵U(n,f) where a slight difference occurs to satisfy thermal data testing, and some very small differences for ²³⁵U(n,f) and ²³⁸U(n,γ) in the keV–MeV region.
10. The electro-atomic sublibrary was taken over from ENDF/B-VII.0=ENDF/B-VI.8. It contains data for 100 materials (all elements) supplied by LLNL.
11. The proton-induced reactions were carried over from ENDF/B-VII.0 with only minor corrections. These were supplied by LANL and the data being mostly to 150 MeV.
12. The deuteron-induced reactions were supplied by LANL, carried over unchanged from ENDF/B-VII.0. This sublibrary contains 5 evaluations.
13. The triton-induced reactions were supplied by LANL, carried over unchanged from ENDF/B-VII.0. This sublibrary contains 3 evaluations.
14. Reactions induced with ³He were supplied by LANL, carried over unchanged from ENDF/B-VII.0. This sublibrary contains 2 evaluations.