Beta-delayed alpha emission Nagy Sándor honlapjára Nagy Sándor: Nukleáris Címszavak Glosszáriumába, melyhez ez a lap is tartozik A Tékába, mely ehhez hasonló animációkhoz/szimulációkhoz vezet Nagy Sándor webhelyén

See also beta-delayed neutron emission beta-delayed neutron decay (neutron emission) & beta-delayed proton emission beta-delayed proton decay (proton emission).

Video demo of the Hungarian Flash animation

The English Flash Flash file to download Letöltés indítása kattintással for offline use|| Az oldal magyar változatához hungarian

The animation presents an example of beta-delayed particle emission. In this particular case the decay process consists of the following steps:

β+ decay:

3217Cl153216S16 + e+ + ν,

Note that the ground state of 32S is stable making up 95% of sulfur in nature. However some of the excited daughter nuclei undergo alpha emission (α decay) ending up as stable 28Si , which is the major natural isotope of silicon (abundance: 92%):

3216S162814Si14 + 42He2.

Details of the chart of nuclides NNDC Chart of Nuclides in the vicinity of 32Cl

In the rollover image of the picture below rollover kép you can see the decay processes starting from 32Cl. The main branch is simple β+ decay (denoted by ε in the chart) that stops at 32S. But a thin branch (representing 5 cases out of 10 000) goes on because the daughter nucleus gets rid of its high excitation energy by emitting an α particle rather than a γ photon. Since the process is very rare we could consider it unimportant if we did not know that the 32S isotope of sulfur that suffers α decay here is absolutely stable at least in its ground state. Moreover, as we can see in the figure further below , the binding energy per nucleon (B/A) is higher for the decaying chlorine isotope than for the silicon isotope formed, and therefore the decay would never occur were it not for the high excitation energy. Note that α decay (a spontaneous process) is typical of much heavier nuclides that have relatively low neutron to proton ratio.
Nuklidtérkép a Cl-32 körül

Binding energy per nucleon of 32Cl and 28Si on the B/A vs. A graph of stable nuclides

Binding energy per nucleon

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Last changed: 2022-01-04