Program - Brookhaven National Laboratory

February 2008) and UKPADD (UKPADD6.12, March 2013) are described, together with the evaluation
methodology and processing procedures adopted to produce the files in ENDF-6 format. Comprehensive
sets of requested decay data have been evaluated on the basis of a series of well-defined specifications, and
have been processed to yield complete and verified evaluated decay data files. Evaluated decay-data parameters
within both libraries include half-lives, branching fractions, alpha, beta and gamma-ray energies
and emission probabilities, total decay energies, mean and/or average alpha, beta and gamma energies,
internal conversion coefficients, internal-pair formation coefficients, and all associated uncertainties. The
computer-based files have been generated in ENDF-6 format, including lists of the references used to produce
the proposed decay schemes and comments that identify any existing inadequacies. UKHEDD2.6
consists of recommended decay data files for 125 radionuclides, 50 of which were re-evaluated between January
2000 and February 2007 on the basis of improvements arising from timely laboratory measurements
- these actinides and their natural decay products are identified with the operation, decommissioning and
disposal of fission-based reactor facilities. UKPADD6.12 consists predominantly of recommended decay
data for activation products of relevance to the European Fusion Programme, and a limited number of
fission products identified with the operation, decommissioning and disposal of fission reactor facilities,
along with various standards that are commonly used to calibrate gamma-ray spectrometers. The most recent
evaluations undertaken in 2011/12 have generated recommended decay data for seven fission products
that contribute significantly to the gamma dose in severe accident scenarios. Recommended decay data
for a total of 595 radionuclides are contained within UKPADD6.12. All evaluations within UKHEDD and
UKPADD have been carried out by A.L. Nichols, while processing and verification procedures were performed
by AMEC staff at Winfrith. New versions of the UKHEDD and UKPADD libraries have regularly
been submitted to the NEA Data Bank for possible inclusion in the JEFF library, and in this manner are
readily accessible to the international community. Historically, data evaluations and assembly of many of
the earlier files have been funded by BNFL plc, Sellafield, and the UK Department of Trade and Industry
(work now identified with the UK Department of Energy and Climate Change) and Euratom through the
UK Atomic Energy Authority/Euratom Fusion Association. * deceased. ** affiliated to Department of
Physics, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH, UK;
and Manipal University, Madhav Nagar, Manipal 576104, Karnataka, India.
Corresponding author: Alan Nichols
PR 26
NUBASE2012
M. Wang, Institute of Modern Physics, CAS, Lanzhou 730000, China; MPIK, D-69117 Heidelberg,
Germany; CSNSM-IN2P3-CNRS, Orsay 91405, France. G. Audi, J. Blachot, CSNSM-IN2P3-CNRS,
Orsay 91405, France. F.G. Kondev, Argonne National Laboratory, 9700 S. Cass Avenue, Argonne,
Illinois 60439, USA. B. Pfeiffer, GSI Helmholtzzentrum für Schwerionenforschung, Planckstr. 1, D-64291
Darmstadt, Germany. X. Xu, Institute of Modern Physics, CAS, Lanzhou 730000, China.
The NUBASE database contains the basic properties of nuclides in their ground and long-lived (>100 ns)
isomeric states: masses, excitation energies of isomers, half-lives, spins/parities, decay modes and their
intensities. This database is mainly derived from Evaluated Nuclear Structure Data Files (ENSDF) and
the Atomic Mass Evaluation (AME), as well as from experimental results from recent literature. NUBASE
is widely used in fundamental researches and applied nuclear sciences. Meanwhile, NUBASE provides a
consistent identification of the nuclear states involved in mass measurements that are used in AME evaluation
to extract the reliable atomic mass values. The early versions of NUBASE were published in 1997[1]
and 2003[2]. A new version NUBASE2012 will be published in December 2012 together with AME2012,
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