Nuclides.net: An integrated environment for computations on radionuclides and their radiation

Full text: The Nuclides.net computational package is of direct interest in the fields of environment monitoring and nuclear forensics. The 'integrated environment' is a suite of computer programs ranging from a powerful user-friendly interface, which allows the user to navigate the nuclide chart and explore the properties of nuclides, to various computational modules for decay calculations, dosimetry and shielding calculations, etc. The main emphasis in Nuclides.net is on nuclear science applications, such as health physics, radioprotection and radiochemistry, rather than nuclear data for which excellent sources already exist. In contrast to the CD-based Nuclides 2000 predecessor, Nuclides.net applications run over the internet on a web server. The user interface to these applications is via a web browser. Information submitted by the user is sent to the appropriate applications resident on the web server. The results of the calculations are returned to the user, again via the browser. The product is aimed at both students and professionals for reference data on radionuclides and computations based on this data using the latest internet technology. It is particularly suitable for educational purposes in the nuclear industry, health physics and radiation protection, nuclear and radiochemistry, nuclear physics, astrophysics, etc. The Nuclides.net software suite contains the following modules/features: a) A new user interface to view the nuclide charts (with zoom features). Additional nuclide charts are based on spin, parity, binding energy etc. b) There are five main applications: (1) 'Decay Engine' for decay calculations of numbers, masses, activities, dose rates, etc. of parent and daughters. (2) 'Dosimetry and Shielding' module allows the calculation of dose rates from both unshielded and shielded point sources. A choice of 10 shield materials is available. (3) 'Virtual Nuclides' allows the user to do decay and dosimetry and shielding calculations on mixtures of nuclides. (4) 'Fission Yield' module gives the user access to fission products and yields for 36 fissioning nuclides (data for spontaneous fission and neutron induced fission with thermal, fast , and 14 MeV neutrons) from the main international datafiles. (5) The 'Universal Nuclide Chart' runs locally on the user computer and displays the most important basic data. It can also be used to simulate decay processes and nuclear reaction paths. in addition: c) Data on 3650 ground states and isomers (increased from 2656 in Nuclides 2000). Data is from internationally recognised sources. 4) 'Fact Sheets' gives important properties derived from the basic data. In addition to heat, neutron, and gamma emission rates, information on radiotoxicity and nuclide transportation given. 5) 'Cross Sections' gives averaged neutron cross-sections from the main international data files. Data includes the cross sections for room temperature, Maxwell averaged, resonance integral, fission averaged, and 14 MeV neutrons. 6) 'News' and 'Forum' gives latest information on Nuclides.net and allow information exchange. In the paper a more detailed description of the applications and data will be given with particular emphasis on environmental monitoring and nuclear forensics. A Case Study on the determination of the 'age' of plutonium particles is presented. (author)