FAIR

The new accelerator facility FAIR is under construction at GSI. Learn more.

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The Creation of New Elements

Fusion reaction of the generation of new elements according to UrQMD model calculations

In experiments at the GSI accelerator facility scientists discovered a total of six new elements.

Chemical elements are produced in stars and in stellar explosions. Ultimately, these elements are the building blocks of all materials that surround us — including every atom of our bodies. However, the universe is also home to a large number of other atoms that do not occur on the earth.

One of the key tasks of the researchers at GSI is to attempt to create previously unknown elements in the laboratory. For the creation of a new element, scientists use two elements existing on Earth of which the atomic nuclei added together have as many protons as the new element. They try to fuse the nuclei of the two elements together in order to create a new atomic nucleus much larger and heavier than the two original nuclei. For this purpose, scientists accelerate charged atoms – so-called ions – of the one element by means of a 120 m long linear accelerator to extremely high velocities of roughly 30,000 kilometres per second. Subsequently, the accelerated ions are “fired” at a very thin foil of the other element. In a very rare cases, e. g. once a week, the two elements fuse to form a new element.

By means of a very sensitive detector, the new element is being identified. Thereby it is decisive that the new element is not stable. It decays into another, lighter element already after splits of a second. During the decay process, it emits a characteristic alpha particle. This process is repeated several times. The detector can precisely measure these emitted alpha particles and thus clearly identify the new element.

In these experiments scientists at the GSI Helmholtzzentrum discovered the chemical elements with atomic numbers 107 to 112.

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Ablauf einer Fusionsreaktion zur Erzeugung neuer Elemente nach UrQMD-Modellrechnung
UrQMD-Collaboration, FIAS, Goethe-Universität Frankfurt

Elements made at GSI

Atomic Number Name Symbol Origin of name Official Acknowledgement* Discovery**
107 Bohrium Bh Niels Bohr
Danish physicist
Nobel prize winner 1922
1997 (December) 1981 (24. February)
108 Hassium Hs German state Hesse 1997 (December) 1984 (14. March)
109 Meitnerium Mt Lise Meitner
Austrian physicist
1997 (December) 1982 (29. August)
110 Darmstadtium Ds Darmstadt
location of GSI
2003 (August) 1994 (9. November)
111 Roentgenium Rg Wilhelm Conrad Röntgen
German physicist
Nobel prize winner 1901
2004 (November) 1994 (8. December)
112 Copernicium Cn Nikolaus Kopernikus
astronomer 15/16 cent.
2010 (February) 1996 (9. February)
(Stand: Juli 2011)
* angegeben ist das Datum der offiziellen Benennung durch die IUPAC. Das Verfahren zur offiziellen Anerkennung ist mehrstufig: 1) Die IUPAC erkennt die Existenz des Elements an. Gleichzeitig fordert sie die Entdecker auf einen Namen vorzuschlagen. 2) Die Entdecker schlagen einen Namen vor. 3) Die IUPAC stellt den vorgeschlagenen Namen ca. sechs Monate in der Fachwelt zur Diskussion. 4) Die IUPAC legt den Namen fest, ggf. mit Abweichungen zum Vorschlag der Entdecker.
** angegeben ist das Datum, an dem das Element zum ersten Mal von der IUPAC anerkannt experimentell nachgewiesen wurde

(status: July 2011)

* the given date is the official date of naming by the IUPAC (International Union of Pure and Applied Chemistry). The procedure for the official acknowledgment has several stages: 1) IUPAC acknowledges the existence of the element. At the same time they prompt the discoverers to propose a name. 2) The discoverers propose a name. 3) IUPAC puts the name up for discussion among the experts for approx. six month. 4) IUPAC decides for a name, subject to changes from the proposal of the discoverers when indicated.

** the given date is the date when the element was experimentally discoverd for the first time, acknowledged by IUPAC.

The Periodical Table of the Elements

In the periodic table, all known chemical elements are represented in tabular form. Each box stands for an element that is a certain kind of atom and each element has a symbol. In the center of the atom is the atomic nucleus, which contains positively charged protons and uncharged neutrons. The elements are classified according to the number of protons in their nuclei - the so-called atomic number. The lightest element with atomic number 1, is hydrogen, and stands at the top left of the periodic table. The numbering starts at the left top of the periodic table and continues line by line to the right below.

The Periodical Table of the Elements
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The Periodical Table of the Elements
Legend
Dark green: natural, stable
Light green: natural, unstable
Yellow: artificial, unstable
Orange: first discovered at GSI, unstable
Grey: not yet confirmed
GSI Helmholtzzentrum für Schwerionenforschung

Further information: SHIP-Experiment