Physics Division ORNL Index Search Comments Disclaimers Rev: Friday, 22-September-2000
| Nuclear Structure Data | Nuclear Astrophysics Data | RadWare | Staff | Physics Division |
The Nuclear Data Project (NDP) program is devoted to the collection and evaluation of nuclear
structure and astrophysics data. The work includes dissemination of compilations, evaluations, and codes
via internet- and www-based information services, as well as publication in journals.
Nuclear Structure Data
The nuclear structure evaluation procedure involves the critical analysis of all literature on nuclei under
study. The evaluators are responsible for preparation of critical reviews with recommended values for a
wide range of nuclear structure properties. Systematic properties are investigated both as a guide in the
evaluation procedure and as a means of gaining new insight into nuclear structure phenomena. The NDP
has been responsible for collecting and evaluating nuclear structure data for 56 mass chains in the mass
region A>200. These evaluations are published in the journal Nuclear Data Sheets and included in the
Evaluated Nuclear Structure Data File (ENSDF).
The nuclear structure evaluation effort has been redirected from mass-chain evaluation to horizontal
evaluation of selective nuclear properties and/or selective nuclei, particularly nuclei in the
far-from-stability regions which are directly related to local on-going research programs.
The project coordinates its work with other evaluation centers comprising the U.S. Nuclear Data
Program which itself is part of the International Nuclear Structure and Decay Data Network.
The work involves the reading and critical analysis of all literature on nuclei in the above mass region.
For each research paper, the evaluators extract the data, compare them with data from other sources, and
prepare summaries with recommended values for a wide range of nuclear structure properties.
Systematic trends in these properties are investigated both as a guide in the evaluation procedure and as a
means of gaining new insight into nuclear structure phenomena.
The data evaluated by the NDP are made available to the research community through the Evaluated
Nuclear Structure Data File (ENSDF), one of several databases maintained by the National Nuclear Data Center at Brookhaven
National Laboratory, and through
publications of the journal Nuclear Data Sheets, published by Academic Press.
Nuclear Astrophysics Data
We have a new program of evaluating and disseminating nuclear data of vital importance for studies in
nuclear astrophysics. Research programs in nuclear astrophysics address some of the most fundamental
questions in nature: What are the origins of the elements that make up our bodies and our world? How
did the solar system, the sun, the stars, and the galaxy form, and how do they evolve? Measurements in
the nuclear laboratory form the empirical foundation for the sophisticated theoretical models of these
astrophysical systems. In many cases, however, new nuclear physics measurements are not rapidly
disseminated to the research community nor rapidly incorporated into astrophysical models. For this
reason, progress in many fundamental problems in nuclear astrophysics can be significantly aided by
more effectively utilizing nuclear data. The ORNL effort addresses this problem by providing new
evaluations of important reactions and disseminating them to the research community in user-friendly
formats that are easily incorporated into astrophysics models. Our evaluation work is focused primarily
on capture reactions on radioactive isotopes on the proton-rich side of stability - reactions that are
important for understanding the element synthesis and energy generation in stellar explosions. We are
also working on reactions that are important for understanding Red Giant Stars and the Solar Neutrino
Problem. Our work utilizes the latest advances in Internet- and WWW-based information services to
disseminate evaluated data to the astrophysics research community. For more information see nuclear
data for nuclear astrophysics.
RadWare
In addition to the evaluation programs, an FTP/www server site has been set up on the ORNL Physics
Division local-area network for storing nuclear structure data.
The FTP/www server site on the ORNL Physics Division local area-network for compilation and
distribution of nuclear-structure data has been set up. The data on this site are in the "RadWare"
"Graphical Level Scheme" format, which is very widely used by the international reaction
gamma/nuclear structure community. The nuclear structure physicists are encouraged to make use of the
service.
The members of the reaction gamma/nuclear structure community are being encouraged also to
contribute their own data by anonymous FTP. Contributed data use the same format, accompanied by
additional information describing, for example, the experiment(s) that generated the level scheme, the
names and institutions of the researchers involved, and references to any publications of the data.
Contributed data are not evaluated in any formal way, but simply checked for internal consistency.
A selection of RadWare-format level schemes created from ENSDF files, by means of a conversion
program, have also been placed on the site with the intent of generating a displayed level scheme. The
response of RadWare users (nuclear structure experimentalists) has been very encouraging.
On-line conversion of data sets from ENSDF-format to RadWare format is also developed, with the aim
of using this method to replace the present archive of ENSDF-converted schemes.
The RadWare software for data analysis is also available to users. Documentation for Radware is given
at http://radware.phy.ornl.gov.
Staff
Yurdanur Akovali, nuclear structure evaluator
Jeffrey Blackmon, nuclear astrophysics evaluator
Mary Ruth Lay, technical staff
David Radford, nuclear structure evaluator
Michael Smith, nuclear astrophysics evaluator
Physics Division
ORNL
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Rev: Friday, 22-September-2000