Recent developments in the distribution of nuclear data

the international weights and measures bureau, has recommended that aU radiometric laboratories take their data from DDEP. AU of the national bodies responsible for maintaining standards within their respective countries have subscribed to that advice. The DDEP is very detailed. It covers alpha, beta and gamma-ray emissions, X-rays and electron emissions and includes the references to the data taken into account in the evaluation. It also carries decay scheme diagrams. The data are available on line as downloadable. pdf files - either individually for each nuclide or as a series of volumes summarizing the updates at particular points in time. 

I think that the data in NuDat 2.3 is the most comprehensive resource world wide, people contributing to it have PhDs in nuclear physics with many years of experience.. .. Most DDEP contributors also contribute to NuDat, so both databases are not really independent, and DDEP has a far more limited scope. JEEE 3.1 [another commonly used database] is not independent, it is mostly based on ENSDF and DDEP. Also, JEFF is frozen in time, being updated every 5—10 years or so. ENSDF and NuDat are updated monthly 

It is not immediately clear, however, whether all of the NuData data has been subject to the same careful, defined, evaluation as the DDEP data. I would support the NPL recommendation of DDEP followed hy ENSDF, at least for data for routine gamma spectrometry purposes. For nuclear-level data, as opposed to gamma-ray energies, the online NuData resource is excellent. I have no hesitation in recommending it. 

On-line sources of data from routinely updated databases are excellent in the sense that one always has the most up-to-data information - much more reassuring than the book and CD-ROMS we have been used to. There is, however, a down-side to that. Quality-assurance processes may require the data source for a particular measurement to be specified within the written method. How would the QA manager feel about taking data from a continuously changing source that does not have an audit trail We have a duty to use the most reliable source of data, but we could end up in a situation where, at the 

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