A short history of the Karlsruhe Nuclide Chart (in English)
Karlsruher Nuklidkarte
The following text is based on a similar article in Radioactivity, Radionuclides Radioationby Joseph Magill and Jean Galy, Springer Verlag 2005. For more information see http://www.nucleonica.com/nuclTxtbook.aspx
For almost 50 years, the Karlsruhe Nuclide Chart has provided scientists with structured, valuable information on half-lives, decay modes, and the energies of radioactive nuclides. The origins of the Chart date back to 1956, the founding year of the Karlsruhe Research Centre, where the activity was initiated at the then new Institute for Radiochemistry (later the Institute for Instrumental Analytics). Since the first edition in 1958, more than 150,000 wall charts and 200,000 brochures with fold-out charts have been published.
After World War II, Germany was only allowed to resume work in the field of nuclear engineering and radioactivity in 1955, following the first “International Conference on Peaceful Uses of Atomic Energies” in Geneva. There was a great demand for professional training and education in the rapidly developing disciplines of nuclear physics, radiochemistry, and reactor technology.
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1st Edition, 1958
In 1956, Walter Seelmann-Eggebert was appointed professor of radiochemistry at the Karlsruhe Technical University and director of the Radiochemistry Institute in the Nuclear Research Centre (at that time known as the Kernreaktor Bau- und Betriebsgesellschaft Karlsruhe). Courses on radiochemical isotopes were held at the Institute, and the Karlsruhe Nuclide Chart was created in the scope of this teaching activity. The chart gave a well-structured overview of the essential properties of the nuclides already known at that time (half-lives, modes of decay, energies of the emitted particles, gamma radiation etc.). The nuclides were arranged with the number of neutrons and protons shown on the abscissa and the ordinate, respectively. The characteristic data on each nuclide are summarized in a box positioned at the intersection points of the corresponding neutron and proton numbers. The decay mode is represented by a specific colour (black = stable nuclide, red = β+ decay or electron capture; blue = β– decay; yellow = α decay; white = isomeric transition). Apart from comprehensive studies of original publications (for example, based on the Recent References of the Nuclear Data Sheets), current editions of the most significant standard data compilations were used as literature sources, such as the Nuclear Data Sheets of the National Research Council, Washington D.C., or the “Tables of Isotopes”.
Already in the 1st edition of the nuclide chart, which appeared in the shape of a wall chart in 1958 produced by Walter Seelmann- Eggebert and Gerda Pfennig from the Radiochemical Institute, several thousands of copies were made available to institutions abroad. Moreover, there was a single-sheet edition in DIN A4 format for use on desktops. At that time, the nuclide chart comprised 267 stable and over 1,030 unstable nuclides, as well as more than 220 isomers of the hitherto 102 known elements – from hydrogen to nobelium.
2nd Edition, 1961
Due to great demand, a 2nd edition with a number of reprints was issued already in 1961. The editorial work was once again carried out by Walter Seelmann-Eggebert and Gerda Pfennig, with the assistance of Prof. Helmut Münzel and Gisela Zundel. This edition of the nuclide chart comprised 103 elements and approximately 70 new unstable nuclides.
3rd Edition, 1968
On account of the global distribution of the nuclide chart, a version containing explanations translated into four languages (German, English, French, and Spanish) was made for the 3rd edition released in 1968. Spontaneous fission, a new mode of decay, was displayed in green. The atomic weights were henceforth related to carbon (12C = 12). The number of elements amounted to 105 and about 250 new nuclides were added, so that the number of fields surpassed a total of 1,600.
4th Edition, 1974
In the 4th edition of 1974, the energies of all nuclides were reported in kilo electron volts (keV), since Ge(Li) detectors, rather than Nal crystals, were generally used to measure -radiation in the meantime. This accounted for an increased precision in energy determination and required re-working of all the data. Due to the lack of recent evaluations, a large amount of original literature had to be consulted. Owing to the increased application of physical separation methods, more and more short-lived nuclides were detectable, particularly among the fission products, so that the number of nuclides increased again by about 300 to yield a total of more than 1,900.
5th Edition, 1981
In the early 1981, the 5th edition by Seelmann-Eggebert, Pfennig and Münzel, and Hanns Klewe-Nebenius was published. Again due to lack of recent evaluations for many chains since the 4th edition, a very large number of original publications had to be consulted. This update took approximately three years. Changes of decay-related data had to be made in about three quarters of all nuclides. The application of online mass-separators enabled studying nuclides of increasingly shorter half-lives, so that the number of new nuclides increased by 300 such that now 107 elements with a total of 2,224 nuclides were included. Proton decay was introduced as a new mode of decay (color: orange). Atomic weights, abundances, and fission yields were brought in line with the latest scientific research, and tables of calibration nuclides, densities, and constants were included. The nuclide chart was in great demand following the Chernobyl accident and as a consequence, various reprints were required.
6th Edition, 1995
A new edition of the chart only appeared after a period of more than ten years, when it was decided to produce a new 6th edition of the nuclide chart to reflect the latest development in scientific knowledge. Of particular interest in this context was the work of the Gesellschaft für Schwerionenforschung (GSI) in Darmstadt, Germany, which led to the discovery of four new heavy elements with the atomic number 108 to 111. The update was implemented by Gerda Pfennig and Hanns Klewe-Nebenius. This 6th edition was dedicated to the initiator of the Karlsruhe nuclide chart, Walter Seelmann-Eggebert, who died in 1988. In all changes to about one-half of all nuclide fields had to be made in the course of this revision through which the number of fields increased by more than 460 to a total of approximately 2,690 nuclides of 111 elements by now. The cluster emission (e.g. C-14, O-20, colour: purple) was introduced as a new decay mode. In addition, the neutron cross-sections, the natural abundances of stable isotopes, the atomic weights, and the cumulative chain yields for the thermal fission of U235 were brought up to date, along with the tables in the accompanying booklet.
Revised 6th Edition, 1998:
When a reprint became necessary in 1998, apart from making minor revisions in the data fields, the newly discovered element (112) was taken into account. The new official names of elements 104 – 108 were included and 33 revised or new nuclides, particularly in the group of transuranium elements 93 – 112, were included. GSI kindly made their updated database available for this extension. Furthermore, decay data of about 150 other nuclides which had been published since 1995 were included. These were mainly very short-lived nuclides positioned on the borderlines of the chart and of interest in astrophysics.
Revised 6th Edition, 2001:
The constants on the inside page of the booklet were updated in 2001.
7th Edition, 2006
In November 2006, the 7th edition of the “Karlsruher Nuklidkarte” by Joseph Magill, Gerda Pfennig and Jean Galy was published. This new editon contains new and updated radioactive decay data on 612 nuclides not found in the previous (1998) edition. In total, nuclear data on more than 2950 experimentally observed nuclides and 690 isomers is presented. Most recent values of the atomic weights, isotopic abundances and cross sections are included together with the thermal fission yields for both 235U and 239Pu. The accompanying booklet has been considerably revised to include a history and overview of nuclear science. The multi-lingual “Explanation of the Chart of the Nuclides” has been extended from the original four languages (English, German, French, Spanish) and now includes Chinese and Russian.
Since the previous 1998 edition of the Karlsruhe Nuclide Chart, many comprehensive nuclear data sources have become available in electronic form on CD-ROM and on the internet. Nevertheless, the paper-based Karlsruhe Nuclide Chart, with its foldout and wall chart versions, remains an aesthetically appealing record of human achievement in nuclear science. It provides a unique overview of current knowledge and is for many the preferred medium for ease of use, convenience and practicality. This new 2006 edition coincides with the 50th anniversary of the “Forschungszentrum Karlsruhe” which has overseen management of the chart since its inception there in 1958. The European Commission’s Joint Research Centre will continue this tradition through support and development of the current and future editions of the chart at the Institute for Transuranium Elements (ITU) in Karlsruhe.
Revised 7th Edition, 2007: the seventh edition was revised in 2007.
