The Karlsruhe Nuclide Chart is a widespread table of nuclides in print.

Characteristics

It is a two-dimensional graphical representation in the Segrè-arrangement with the

neutron number The neutron number (symbol ''N'') is the number of neutrons in a nuclide. Atomic number (proton number) plus neutron number equals mass number: . The difference between the neutron number and the atomic number is known as the neutron excess: . ...

''N'' on the

abscissa In mathematics, the abscissa (; plural ''abscissae'' or ''abscissas'') and the ordinate are respectively the first and second coordinate of a point in a Cartesian coordinate system: : abscissa \equiv x-axis (horizontal) coordinate : ordinate \eq ...

and the

proton number The atomic number or nuclear charge number (symbol ''Z'') of a chemical element is the charge number of its atomic nucleus. For ordinary nuclei composed of protons and neutrons, this is equal to the proton number (''n''p) or the number of pro ...

''Z'' on the

ordinate In mathematics, the abscissa (; plural ''abscissae'' or ''abscissas'') and the ordinate are respectively the first and second coordinate of a point in a Cartesian coordinate system: : abscissa \equiv x-axis (horizontal) coordinate : ordinate \e ...

. Each

nuclide Nuclides (or nucleides, from nucleus, also known as nuclear species) are a class of atoms characterized by their number of protons, ''Z'', their number of neutrons, ''N'', and their nuclear energy state. The word ''nuclide'' was coined by the A ...

is represented at the intersection of its respective neutron and proton number by a small square box with the

chemical symbol Chemical symbols are the abbreviations used in chemistry, mainly for chemical elements; but also for functional groups, chemical compounds, and other entities. Element symbols for chemical elements, also known as atomic symbols, normally consist ...

and the nucleon number ''A''. By columnar subdivision of such a field, in addition to

ground state The ground state of a quantum-mechanical system is its stationary state of lowest energy; the energy of the ground state is known as the zero-point energy of the system. An excited state is any state with energy greater than the ground state ...

s also

nuclear isomer A nuclear isomer is a metastable state of an atomic nucleus, in which one or more nucleons (protons or neutrons) occupy excited state levels (higher energy levels). "Metastable" describes nuclei whose excited states have Half-life, half-lives of ...

s can be shown. The coloring of a field (segmented if necessary) shows in addition to the existing text entries the observed types of

radioactive decay Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is conside ...

of the nuclide and a rough classification of their relative shares: stable, nonradioactive nuclides completely black, primordial radionuclides partially black,

proton emission Proton emission (also known as proton radioactivity) is a rare type of radioactive decay in which a proton is ejected from a atomic nucleus, nucleus. Proton emission can occur from high-lying excited states in a nucleus following a beta decay ...

orange,

alpha decay Alpha decay or α-decay is a type of radioactive decay in which an atomic nucleus emits an alpha particle (helium nucleus). The parent nucleus transforms or "decays" into a daughter product, with a mass number that is reduced by four and an a ...

yellow, beta plus decay/

electron capture Electron capture (K-electron capture, also K-capture, or L-electron capture, L-capture) is a process in which the proton-rich nucleus of an electrically neutral atom absorbs an inner atomic electron, usually from the K or L electron shells. Th ...

red,

isomeric transition A nuclear isomer is a metastable state of an atomic nucleus, in which one or more nucleons (protons or neutrons) occupy excited state levels (higher energy levels). "Metastable" describes nuclei whose excited states have half-lives of 10−9 s ...

(

gamma decay Gamma (; uppercase , lowercase ; ) is the third letter of the Greek alphabet. In the system of Greek numerals it has a value of 3. In Ancient Greek, the letter gamma represented a voiced velar stop . In Modern Greek, this letter normally repr ...

internal conversion Internal conversion is an atomic decay process where an excited nucleus interacts electromagnetically with one of the orbital electrons of an atom. This causes the electron to be emitted (ejected) from the atom. Thus, in internal conversion (o ...

) white,

beta minus decay In nuclear physics, beta decay (β-decay) is a type of radioactive decay in which an atomic nucleus emits a beta particle (fast energetic electron or positron), transforming into an isobar of that nuclide. For example, beta decay of a neutron t ...

blue,

spontaneous fission Spontaneous fission (SF) is a form of radioactive decay in which a heavy atomic nucleus splits into two or more lighter nuclei. In contrast to induced fission, there is no inciting particle to trigger the decay; it is a purely probabilistic proc ...

green, cluster emission violet,

neutron emission Neutron emission is a mode of radioactive decay in which one or more neutrons are ejected from a Atomic nucleus, nucleus. It occurs in the most neutron-rich/proton-deficient nuclides, and also from excited states of other nuclides as in photodisin ...

light blue. For each

radionuclide A radionuclide (radioactive nuclide, radioisotope or radioactive isotope) is a nuclide that has excess numbers of either neutrons or protons, giving it excess nuclear energy, and making it unstable. This excess energy can be used in one of three ...

its field includes (if known) information about its

half-life Half-life is a mathematical and scientific description of exponential or gradual decay. Half-life, half life or halflife may also refer to: Film * Half-Life (film), ''Half-Life'' (film), a 2008 independent film by Jennifer Phang * ''Half Life: ...

and essential energies of the emitted radiation, for stable nuclides and primordial radionuclides there are data on

mole fraction In chemistry, the mole fraction or molar fraction, also called mole proportion or molar proportion, is a quantity defined as the ratio between the amount of a constituent substance, ''ni'' (expressed in unit of moles, symbol mol), and the to ...

abundances in the natural isotope mixture of the corresponding

chemical element A chemical element is a chemical substance whose atoms all have the same number of protons. The number of protons is called the atomic number of that element. For example, oxygen has an atomic number of 8: each oxygen atom has 8 protons in its ...

. Furthermore, for many nuclides cross sections for

nuclear reaction In nuclear physics and nuclear chemistry, a nuclear reaction is a process in which two atomic nucleus, nuclei, or a nucleus and an external subatomic particle, collide to produce one or more new nuclides. Thus, a nuclear reaction must cause a t ...

s with

thermal neutrons The neutron detection temperature, also called the neutron energy, indicates a free neutron's kinetic energy, usually given in electron volts. The term ''temperature'' is used, since hot, thermal and cold neutrons are moderated in a medium with ...

are quoted, usually for the (n, γ)-reaction (

neutron capture Neutron capture is a nuclear reaction in which an atomic nucleus and one or more neutrons collide and merge to form a heavier nucleus. Since neutrons have no electric charge, they can enter a nucleus more easily than positively charged protons, wh ...

), partly fission cross sections for the induced

nuclear fission Nuclear fission is a reaction in which the nucleus of an atom splits into two or more smaller nuclei. The fission process often produces gamma photons, and releases a very large amount of energy even by the energetic standards of radioactiv ...

and cross sections for the (n, α)-reaction or (n, p)-reaction. For the chemical elements cross sections and

standard atomic weight The standard atomic weight of a chemical element (symbol ''A''r°(E) for element "E") is the weighted arithmetic mean of the relative isotopic masses of all isotopes of that element weighted by each isotope's abundance on Earth. For example, ...

s (both averaged over natural isotopic composition) are specified (the relative atomic masses partially as an interval to reflect the variability of the composition of the element's natural isotope mixture). For the nuclear fission of ²³⁵U and ²³⁹Pu with thermal neutrons, percentage isobaric chain yields of

fission product Nuclear fission products are the atomic fragments left after a large atomic nucleus undergoes nuclear fission. Typically, a large nucleus like that of uranium fissions by splitting into two smaller nuclei, along with a few neutrons, the releas ...

s are listed.

History, editions

The first printed edition of the Karlsruhe Nuclide Chart of 1958 in the form of a wall chart was created by Walter Seelmann-Eggebert and his assistant Gerda Pfennig. Walter Seelmann-Eggebert was director of the

Radiochemistry Radiochemistry is the chemistry of radioactive materials, where radioactive isotopes of elements are used to study the properties and chemical reactions of non-radioactive isotopes (often within radiochemistry the absence of radioactivity leads t ...

Institute in the 1956 founded "Kernreaktor Bau- und Betriebsgesellschaft mbH" in

Karlsruhe Karlsruhe ( ; ; ; South Franconian German, South Franconian: ''Kallsruh'') is the List of cities in Baden-Württemberg by population, third-largest city of the States of Germany, German state of Baden-Württemberg, after its capital Stuttgart a ...

, Germany (a predecessor institution of the later "(Kern-)Forschungszentrum Karlsruhe", nowadays

Karlsruhe Institute of Technology The Karlsruhe Institute of Technology (KIT; ) is both a German public research university in Karlsruhe, Baden-Württemberg, and a research center of the Helmholtz Association. KIT was created in 2009 when the University of Karlsruhe (), founde ...

) and appointed professor of radiochemistry at the Karlsruhe Technical University. Radiochemical isotope courses were held at the institute, and in the context of these teaching courses the Karlsruhe Nuclide Chart arose, which was intended to be a well-structured overview of the essential properties of the nuclides already known at that time. In the following decades, the Karlsruhe Nuclide Chart was published and revised several times. In addition to other co-authors, Seelmann-Eggebert († 1988) was involved up to the 5th edition in 1981, Pfennig († 2017) up to the 9th edition in 2015. In 2006, the management of the Karlsruhe Nuclide Chart changed over from Forschungszentrum Karlsruhe to the

Institute for Transuranium Elements The Institute for Transuranium Elements (ITU) is a nuclear research institute in Karlsruhe, Germany. The ITU is one of the seven institutes of the Joint Research Centre, a Directorate-General of the European Commission. The ITU has about 300 sta ...

(ITU) of the

Joint Research Centre The Joint Research Centre (JRC) is the European Commission's science and knowledge service which employs scientists to carry out research in order to provide independent scientific advice and support to European Union (EU) policy. Leadersh ...

(JRC) of the

European Commission The European Commission (EC) is the primary Executive (government), executive arm of the European Union (EU). It operates as a cabinet government, with a number of European Commissioner, members of the Commission (directorial system, informall ...

(EC), then in 2012 to Nucleonica GmbH, a spin-off company of the JRC-ITU. The following summary table regarding the individual editions of the Karlsruhe Nuclide Chart also expresses the scientific progress in the field of discovery/exploration of the nuclides and new chemical elements. ? = Sources incongruent or explicit/implicit numerical data missing or inclusion of nuclear isomers in figures unclear.

Versions

The Karlsruhe Nuclide Chart is primarily published as a fold-out chart (size A4) or as a wall chart (size 0.96 m × 1.40 m). There are also larger sizes (roll map, auditorium chart and "carpet"). Since 2014, an internet-based version "Karlsruhe Nuclide Chart Online (KNCO)" with regular updates is offered via the

Nucleonica Nucleonica is a nuclear science web portal A web portal is a specially designed website that brings information from diverse sources, like emails, online forums and search engines, together in a uniform way. Usually, each information source gets ...

nuclear science internet portal. To support nuclear education, a simplified school version, the KNClight has been developed. The largest known version of the Karlsruhe Nuclide Chart is located in the Reactor Institute Delft, being 13 m × 19 m in size.

References

J. Magill, R. Dreher, Zs. Sóti: ''Karlsruher Nuklidkarte / Chart of the Nuclides.'' 11th edition. Nucleonica GmbH, Karlsruhe 2022, (wall chart), (fold-out chart), (auditorium chart), (accompanying booklet). Multilingual (German, English, French, Spanish). Zs. Sóti, J. Magill, R. Dreher: Karlsruhe Nuclide Chart – New 10th edition 2018, EPJ Nuclear Sci. Technol. Volume 5, 2019, https://doi.org/10.1051/epjn/2019004 {{cite web , url=https://www.nucleonica1.com/Application/KNClight/index.html , title=KNClight - The school version of the Karlsruhe Nuclide Chart Tables of nuclides