# Introduction to the Karlsruhe Nuclide Chart, 7th edition.

The brochure with fold-out chart
The wallchart, 1.00m x 1.40m

7th edition (2006) of the “Karlsruher Nuklidkarte” contains new and updated radioactive decay data on more than 600 nuclides not found in the previous (1998) edition. In total, nuclear data on 2962 experimentally observed nuclides and 692 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.

For almost 50 years, the Karlsruhe Nuclide Chart has provided scientists and students with structured, accurate information on the half-lives and decay modes of radionuclides, as well as the energies of emitted radiation. Beyond the more traditional physical sciences such as health physics and radiation protection, nuclear and radiochemistry, and astrophysics, the Chart is now in wide and common usage in the life and earth sciences (biology, medicine, agriculture, geology, etc.). An important characteristic of the Chart is its great didactic value for education and training in the nuclear sciences. It has been used in training programmes worldwide and is a valuable and welcome addition to many books on nuclear science including school physics textbooks. 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 fold-out 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.

The Karlsruhe Chart of the Nuclides is available as both a 44 page brochure with 20 page fold-out nuclide chart and as a wallchart (1.00 m x 1.40 m). Further information can be found in the flyer.

# Press Releases and Publications

• Trazando el paisaje nuclear 50 años de historia de la Karlsruher Nuklidkarte, Notas Historicas, Revista Española de Física (Vol. 24 nº 1, 2010 pag 76-80), http://www.rsef.org

# Explanation of the Nuclide Chart - translations

Karlsruhe Nuclide Chart wallchart, 7th Edition

Are you interested in translating the "Explanation of the Chart of the Nuclides" into your own language? If so, please contact: Joseph Magill (joseph.magill@nucleonica.com)

# Explanation of the Nuclide Chart (Examples)

The multi-lingual "Explanation of the Karlsruhe Nuclide Chart" is quite technical and very concise. In the following section, some examples are discussed.To better understand the nuclide box content using decay schemes , see Decay Schemes

## He 8

The He8 nuclide box structure in the Karlsruhe Nuclide Chart

The first example described is He8:

ß- 9.7...

The ß- symbol implies that this nuclide a ß- emitter. The fact that there are no other main decay modes (see list below) means that the branching ratio for ß- emission is 1. This fact also determines that the nuclide box is entirely blue.

The main decay modes are:

p: proton decay

α: alpha decay

ε: electron capture

ß+: positron decay

Iγ: isomeric transition

sf: spontaneous fission

ce: cluster emission

n: neutron emission

Note that the entries below the "ß- 9.7..." on γ and beta delayed particle emission ßn and ßt refer to subsidiary modes - these are not main decay modes.

The 9.7 refers to the end point energy of the ß- particle in MeV. The actual value in the database is 9.668. However, this value is rounded to give only one digit following the decimal point.

The following three dots "..." imply that there is more than one ß- particle emitted. If there are no dots after the ß- energy, then there is only a single ß- particle emitted.

The fact that only a single energy is given, means that the 9.7 MeV ß- particle has both the highest branching ratio AND the highest energy. In the case of C15, for example, the entry in the nuclide box is ß- 4.5; 9.8... which means that there are more than two ß- particles emitted. The first energy, 4.5 MeV, refers to ß- particle with the highest branching ratio. The second energy, 9.8 MeV, refers to ß- particle with the highest energy. This notation holds only for ß- and ß+ emission. For other particles, if two energies are given, then these correspond to the two most probable (highest branching ratios) emissions.

γ 981; 478*

The gamma emissions, denoted by the symbol γ and followed by the gamma energies, refer to subsidiary decay modes associated with the main ß- decay mode. This entry on gamma emission must be below a main decay mode (in this case the ß- mode). The fact that the gamma emission entry is above the ßn and ßt entries implies that the gamma emission probability is higher than the ßn, ßt branching ratio.

The two numbers 981; 478* refer to the two most important gamma lines associated with the decay of He8. The 981 refers to the γ energy in keV. The value is rounded to the nearest integer keV. The 478* with an asterisk, refers to the γ energy in keV associated with the delayed particle emission.

ßn; ßt

This entry implies that there are two beta delayed particle emissions associated with the decay of He8: beta-delayed neutron emission ßn and beta-delayed triton emission ßt.

## Te 108

Te108 in the Karlsruhe Nuclide Chart

The main modes of decay are ß+ and alpha emission, respectively. The fact that the ß+ is above the alpha indicates that the branching ratio for ß+ emission is greater than 50%. The branching ratio for the alpha emission is greater than 5 but less than 50%.

Following the ß+ entry there is no energy given - this means that the ß+ energy has not been measured. It can of course be calculated.

The alpha emission, which has a branching ratio of between 5 and 50%, gives rise to an alpha particle energy of 3.317 MeV.

The beta delayed proton emission entry is ßp 2-3. This implies that there is a range of protons emitted. Had the notation ßp 2.5... been used, for example, this would mean that the most probable proton energy is 2.5 MeV. But in this case it is not known what the most probable proton energy is.

A simplified decay scheme is shown below.

Simplified decay scheme for Te108

## K 51

K 51 in the Karlsruhe Nuclide Chart

In the case of K 51, the beta delayed neutron entry is ßn 2.23; 0.84. In contrast to the case for ß- and ß+ emission, this implies that the 2.23 and the 0.84 are the two most probable neutron energies.

## Co 60

Co 60 in the Karlsruhe Nuclide Chart

Ground State

ß- 0.3; 1.5...

Endpoint energy of the ß- particle with the highest branching ratio is 0.3 MeV.

Endpoint energy of the ß- particle with the highest energy is 1.5 MeV.

There are two associated gamma transitions at 1332 keV and 1173 keV.

Metastable state

Iγ 59 e-

The main decay mode of the metastable state is by isomeric transition Iγ. The energy of the emitted gamma photon is 59 keV. The fact that the photon energy is followed by e- implies that the transition is highly converted (conversion coefficient greater than 1). Note that conversion electrons e- have no energy information in the Karlsruhe Nuclide Chart. This is just a "flag" which indicates that conversion electrons are involved.

ß-...

denotes ß- transitions with known energies for which the sum of their branching ratios is less than 1%.

γ (1332...)

The brackets () indicates that the intensities of the gamma transitions are less than 1%. The main gamma energy, however, is at 1332 keV.

Co 60 Decay Scheme: full size, black background
Co 60m Decay Scheme: full size, black background

$\sigma$ 58

(n, γ)-cross sections for the formation of the ground state of Co 61 by thermal neutrons (barn)

## Cs 137

Ground State

ß- 0.5; 1.2...

Endpoint energy of the ß- particle with the highest branching ratio is 0.5 MeV.

Endpoint energy of the ß- particle with the highest energy is 1.2 MeV.

m;g

The Cs 137 ground state decays directly to the excited and ground state of the daughter Ba137. Since m appears first in "m;g" this means decay to the isomeric state has a higher branching ratio (i.e. 94%).

There is an associated gamma transitions from Ba137m to the ground state at 662 keV.

Cs 137 Decay Scheme: full size, black background
Cs 137 in the Karlsruhe Nuclide Chart

$\sigma$ 0.2 + 0.07

(n, γ)-cross sections for the formation of the metastable and the ground state of Cs 138 by thermal neutrons (barn)

## Eu 152

Eu 152 in the Karlsruhe Nuclide Chart

Ground State

ε;ß+...

The main decay mode is electron capture. The ß+... refers to the fact that branching ratio for positron emission is less than 1%.

ß- 0.7; 1.5

Endpoint energy of the ß- particle with the highest branching ratio is 0.7 MeV.

Endpoint energy of the ß- particle with the highest energy is 1.5 MeV.

The two main (highest emission probabilities) gamma transitions are at 122 keV and 344 keV.

 Eu 152n Decay Scheme Eu 152m Decay Scheme Eu 152 Decay Scheme

# Recent Scientific Progress

• N. Kinoshita1 et al., A Shorter 146Sm Half-Life Measured and Implications for 146Sm-142Nd Chronology in the Solar System. Science 30 March 2012: Vol. 335 no. 6076 pp. 1614-1617, link. See also ScienceDaily
• Identification of 45 New Neutron-Rich Isotopes Produced by In-Flight Fission of a 238U Beam at 345 MeV/nucleon, Tetsuya Ohnishi et al., J. Phys. Soc. Jpn. 79 (2010) 073201 (5 pages)http://jpsj.ipap.jp/link?JPSJ/79/073201/pdf
• Workshop on the Atomic Properties of the Heaviest Elements, Sept. 25-27th 2006, Eur. Phys. J. D 45, 1-2 (2007).
• First observation of ß-delayed three-proton emission in 45Fe. K. Miernik et al., Phys. Rev. C 76, 041304(R) (2007) abstract
• First Direct Observation of Two Protons in the Decay of 45Fe with a Time-Projection Chamber, J. Giovinazzo et al., Phys. Rev. Lett. 99, 102501 (2007) abstract
• Two-Proton Correlations in the Decay of 45Fe, K. Miernik et al., Phys. Rev. Lett. 99, 192501 (2007) abstract
• Discovery of 40Mg and 42Al suggests neutron drip-line slant towards heavier isotopes, T. Baumann et al., Nature 449, 1022-1024 (25 October 2007), abstract download pdf
• Synthesis and decay properties of superheavy elements, Y. Oganessian, Pure Appl. Chem., 78, 889 (2006).full paper
• Reaching the limits of nuclear Stability, M. Thoennessen, Rep. Prog. Phys. 67 (2004) 1187-1232.
• New determination of the half-life of 205Bi, J. Kuhnhenn et al., Radiochim. Acta 92, 233-235 (2004).
• Direct Observation of Bound Beta Decay at the FRS/ESR, 2001. Full Paper
• Half-life of Re187= 42.2+-1.3 Gy: M. Lindner et al., Geochim. Cosmochim. Acta 53, 1597 (1989).