Nuclear Data Sheets Symbols and Abbreviations

The IAEA Nuclear Data Section convened the 18th meeting of the International Network of Nuclear Structure and Decay Data Evaluators at the IAEA Headquarters, Vienna, 23 to 27 March 2009. This meeting was attended by 22 scientists from 14 Member States, plus IAEA staff, concerned with the compilation, evaluation and dissemination of nuclear structure and decay data. A summary of the meeting, recommendations/conclusions, data centre reports, and various proposals considered, modified and agreed by the participants are contained within this document. The International Network of Nuclear Structure and Decay Data (NSDD) Evaluators holds biennial meetings under the auspices of the IAEA, and consists of evaluation groups and data service centres in several countries. This network has the objective of providing up-to-date nuclear structure and decay data for all known nuclides by evaluating all existing experimental data. Data resulting from this international evaluation collaboration is included in the Evaluated Nuclear Structure Data File (ENSDF) and published in the journals Nuclear Physics A and Nuclear Data Sheets (NDS).

The International Network of Nuclear Structure and Decay Data (NSDD) Evaluators consists of a number of evaluation groups and data service centres in several countries that appreciate the merits of working together to maintain and ensure the quality and comprehensive content of the ENSDF database (Evaluated Nuclear Structure Data File). Biennial meetings of the network are held under the auspices of the International Atomic Energy Agency (IAEA) to assign evaluation responsibilities, monitor progress, discuss improvements and emerging difficulties, and agree on actions to be undertaken by individual members. The evaluated data and bibliographic details are made available to users via various media, such as the journals Nuclear Physics A and Nuclear Data Sheets ,t he World Wide Web, on CD-ROM, wall charts of the nuclides and Nuclear Wallet Cards. While the ENSDF master database is maintained by the US National Nuclear Data Center at the Brookhaven National Laboratory, these data are also available from other nuclear data centres including the IAEA Nuclear Data Section. The Abdus Salam International Centre for Theoretical Physics (ICTP), Trieste, Italy, in cooperation with the IAEA, organizes workshops on NSDD at regular intervals. The primary aims of these particular workshops are to provide hands-on training in the data evaluation processes, and to encourage new evaluators to participate in NSDD activities. The technical contents of these NSDD workshops are described, along with the rationale for the inclusion of various topics.

This manual describes the organization and structure of the Evaluated Nuclear Structure Data File (ENSDF). This computer-based file is maintained by the National Nuclear Data Center (NNDC) at Brookhaven National Laboratory for the international Nuclear Structure and Decay Data Network. For every mass number (presently, A less than or equal to 263), the Evaluated Nuclear Structure Data File (ENSDF) contains evaluated structure information. For masses A greater than or equal to 45, this information is documented in the Nuclear Data Sheets; for A < 45, ENSDF is based on compilations published in the journal Nuclear Physics. The information in ENSDF is updated by mass chains with a present cycle time of approximately six years. The body of a data set is composed of numeric data records which describe the measured or deduced properties of levels, ..gamma.. rays, ..cap alpha.. particles, etc. These records are associated with the level which decays (for gamma records) or the level which is populated (for beta, ec, or alpha records). Thus, each level record is followed by a group of records describing charged-particle decay into the level and ..gamma..-ray decay out of the level. (WHK)

The Panel on Basic Nuclear Data Compilations believes that it is important to provide the user with an evaluated nuclear database of the highest quality, dependability, and currency. It is also important that the evaluated nuclear data are easily accessible to the user. In the past the panel concentrated its concern on the cycle time for the publication of A-chain evaluations. However, the panel now recognizes that publication cycle time is no longer the appropriate goal. Sometime in the future, publication of the evaluated A-chains will evolve from the present hard-copy Nuclear Data Sheets on library shelves to purely electronic publication, with the advent of universal access to terminals and the nuclear databases. Therefore, the literature cut-off date in the Evaluated Nuclear Structure Data File (ENSDF) is rapidly becoming the only important measure of the currency of an evaluated A-chain. Also, it has become exceedingly important to ensure that access to the databases is as user-friendly as possible and to enable electronic publication of the evaluated data files. Considerable progress has been made in these areas: use of the on-line systems has almost doubled in the past year, and there has been initial development of tools for electronic evaluation, publication, and dissemination. Currently, the nuclear data effort is in transition between the traditional and future methods of dissemination of the evaluated data. Also, many of the factors that adversely affect the publication cycle time simultaneously affect the currency of the evaluated nuclear database. Therefore, the panel continues to examine factors that can influence cycle time: the number of evaluators, the frequency with which an evaluation can be updated, the review of the evaluation, and the production of the evaluation, which currently exists as a hard-copy issue of Nuclear Data Sheets.

The energy and photon intensity of gamma rays as seen in thermal-neutron capture are presented ordered by Z, A of target nuclei. All gamma-rays with intensity of {ge}2% of the strongest transition are included. The strongest transition is indicated in each case. Where the target nuclide mass number is indicated as nat the natural target was used. The gamma energies given are in keV. The gamma intensities given are relative to 100 for the strongest transition. All data for A > 44 are taken from Evaluated Nuclear Structure Data File (4/97), a computer file of evaluated nuclear structure data maintained by the National Nuclear Data Center, Brookhaven National Laboratory, on behalf of the Nuclear Structure and Decay and Decay Data network, coordinated by the International Atomic Energy Agency, Vienna. These data are published in Nuclear Data Sheets, Academic Press, San Diego, CA. The data for A {le} 44 is taken from ``Prompt Gamma Rays from Thermal-Neutron Capture,`` M.A. Lone, R.A. Leavitt, D.A. Harrison, Atomic Data and Nuclear Data Tables 26, 511 (1981).

The energy and photon intensity of gamma rays as seen in thermal-neutron capture are presented in ascending order of gamma energy. All those gamma-rays with intensity of {ge} 2% of the strongest transition are included. The two strongest transitions seen for the target nuclide are indicated in each case. Where the target nuclide mass number is indicated as nat the natural target was used. The gamma energies given are in keV. The gamma intensities given are relative to 100 for the strongest transition. All data for A > 44 are taken from Evaluated Nuclear Structure Data File (4/97), a computer file of evaluated nuclear structure data maintained by the National Nuclear Data Center, Brookhaven National Laboratory, on behalf of the Nuclear Structure and Decay and Decay Data network, coordinated by the International Atomic Energy Agency, Vienna. These data are published in Nuclear Data Sheets, Academic Press, San Diego, CA. The data for A {le} 44 is taken from ``Prompt Gamma Rays from Thermal-Neutron Capture,`` M.A. Lone, R.A. Leavitt, D.A. Harrison, Atomic Data and Nuclear Data Tables 26, 511 (1981).

Richard Guy Helmer

This manual describes the organization and structure of the Evaluated Nuclear Structure Data File (ENSDF). This computer-based file is maintained by the National Nuclear Data Center (NNDC) at Brookhaven National Laboratory for the international Nuclear Structure and Decay Data Network. For every mass number (presently, A {le} 293), the Evaluated Nuclear Structure Data File (ENSDF) contains evaluated structure information. For masses A {ge} 44, this information is published in the Nuclear Data Sheets; for A < 44, ENSDF is based on compilations published in the journal Nuclear Physics. The information in ENSDF is updated by mass chain or by nuclide with a varying cycle time dependent on the availability of new information.

Evaluation of nuclear structure data is a world wide effort to standardize the published nuclear data. This standardization led to generation of table of isotopes, Nuclear Data sheets, Nuclear Wallet Cards etc. This paper deals with two aspects of evaluation of nuclear structure data. First, the problems arising out of some of the recent publications and how to tackle them at pre-publication stage. Second, there is large amount of experimental data available on the NNDC site 1 . Of these data the half-life values, spin and parity is the most important set of values to understand the nucleon-nucleon interaction within a given nucleus. However, it is observed in our work that the quantum of half-life, spin and parity values measured, in comparison to the number of excited states, in any given nuclei, is very low. Thus, indicating that very few experimental results are available in terms of half-life measurements, spin measurements and determination of parity. This survey besides being an indicator of the quantum of measurements carried out can also be a guide to future experimentalists by highlighting the areas of nuclear chart where measurements are fewer in number.

This manual is intended as a guide for Nuclear Science References (NSR) compilers. The basic conventions followed at the National Nuclear Data Center (NNDC), which are compatible with the maintenance and updating of and retrieval from the Nuclear Science References (NSR) file, are outlined. The NSR database originated at the Nuclear Data Project (NDP) at Oak Ridge National Laboratory as part of a project for systematic evaluation of nuclear structure data.1 Each entry in this computer file corresponds to a bibliographic reference that is uniquely identified by a Keynumber and is describable by a Topic and Keywords. It has been used since 1969 to produce bibliographic citations for evaluations published in Nuclear Data Sheets. Periodic additions to the file were published as the ''Recent References'' issues of Nuclear Data Sheets prior to 2005. In October 1980, the maintenance and updating of the NSR file became the responsibility of the NNDC at Brookhaven National Laboratory. The basic structure and contents of the NSR file remained unchanged during the transfer. In Chapter 2, the elements of the NSR file such as the valid record identifiers, record contents, and text fields are enumerated. Relevant comments regarding a new entry into the NSR file and assignment of a keynumber are also given in Chapter 2. In Chapter 3, the format for keyword abstracts is given followed by specific examples; for each TOPIC, the criteria for inclusion of an article as an entry into the NSR file as well as coding procedures are described. Authors preparing Keyword abstracts either to be published in a Journal (e.g., Nucl. Phys. A) or to be sent directly to NNDC (e.g., Phys. Rev. C) should follow the illustrations in Chapter 3. The scope of 1See W.B.Ewbank, ORNL-5397 (1978). the literature covered at the NNDC, the categorization into Primary and Secondary sources, etc., is discussed in Chapter 4. Useful information regarding permitted character sets, recommended abbreviations, etc., is given in the Appendices. The NSR database has been in existence for decades, and responsibility for its upkeep has passed through many hands. Those familiar with the contents of NSR will note that not all of the formats and conventions discussed in this manual have always been adhered to. In recent years, however, these conventions have been followed fairly consistently, and it is expected that the preparation of new entries will follow these guidelines. The most up-to-date information about NSR contents and policies can be found at the NSR web site: http://www.nndc.bnl.gov/nsr. This manual is an update to BNL-NCS-51800 (Rev. 08/96) by S. Ramavataram and C.L. Dunford. Discussions with Mark Kellett of the IAEA are gratefully acknowledged, as are comments and suggestions from the NNDC staff and members of the U.S. Nuclear Data Program. This manuscript has been authored by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH1-886 with the U.S.Department of Energy.

Nuclear Data Sheets for A = 152

Spontaneous fission activities

Recent References: January 1998 through December 1998

Nuclear Data Sheets for170Ta

Nuclear Data Sheets for A = 81