Nuklear isomer

En nuklear isomer er en metastabil tilstand af en atomkerne forårsaget af eksitation af en eller flere af dens nukleoner (protoner eller neutroner).

De første nukleare isomerer (Uran Z/Uran X₂), der nu kendes som Protactiniumisotoper, blev opdaget af Otto Hahn i 1921.

Grundstoffet Hafnium, der er opkaldt efter København har også nukleare isomerer. Den nukleare isomer ^178m2Hf besidder en forbavsende høj excitationsenergi for en isomer med relativ lang halveringstid, og det har ført til spekulationer om at udnytte denne energi, 1,33 gigajoule, svarende til sprængkraften af 317 kg TNT, per gram af denne isomer.

I 2013 blev der opdaget flere nukleare isomer tilstande i bismuth-212. Disse nukleare isomer tilstande er blevet testet til brug i et slags genopladeligt atombatteri ved GSI-laboratoriet i den tyske by Darmstadt.^[1]^[2]^[3]

Kilder/referencer

^ 20. jul 2013, ing.dk: Forskere er kommet et skridt nærmere atombatteriet. Atombatterier har potentiale til at lagre en million gange mere energi end almindelige batterier. Nu er forskerne tættere på at have luret, hvordan energien kan lagres., backup
^ 20 March 2013, surrey.ac.uk: A revolutionary ‘nuclear battery’ a step closer
^ 2013, epubs.surrey.ac.uk: Direct observation of long-lived isomers in 212-Bi, backup Citat: "...While the excitation energy of the first isomer of 212-Bi was confirmed, the second isomer was observed at 1478(30) keV...Both the energy and half-life differences can be understood as being due a substantial, though previously unrecognised, internal decay branch for neutral atoms. Earlier shell-model calculations are now found to give good agreement with the isomer excitation energy. Furthermore, these and new calculations predict the existence of states at slightly higher energy that could facilitate isomer de-excitation studies...", backup

Se også

Eksterne henvisninger

Nuclear isomer

[1] 20. jul 2013, ing.dk: Forskere er kommet et skridt nærmere atombatteriet. Atombatterier har potentiale til at lagre en million gange mere energi end almindelige batterier. Nu er forskerne tættere på at have luret, hvordan energien kan lagres., backup

[2] 20 March 2013, surrey.ac.uk: A revolutionary ‘nuclear battery’ a step closer

[3] 2013, epubs.surrey.ac.uk: Direct observation of long-lived isomers in 212-Bi, backup Citat: "...While the excitation energy of the first isomer of 212-Bi was confirmed, the second isomer was observed at 1478(30) keV...Both the energy and half-life differences can be understood as being due a substantial, though previously unrecognised, internal decay branch for neutral atoms. Earlier shell-model calculations are now found to give good agreement with the isomer excitation energy. Furthermore, these and new calculations predict the existence of states at slightly higher energy that could facilitate isomer de-excitation studies...", backup

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