How can metastable isotopes exist?

In summary, the reason for the half-life in alpha and beta decay is due to the strong nuclear force and the need for quantum tunnelling. In beta minus decay, the extra proton causes repulsion and the nucleus can only reach a higher energy state through quantum tunnelling. However, this higher energy state becomes a lower one due to the Pauli exclusion principle. In beta plus decay, the energy barrier is also due to the Pauli exclusion principle, but once beta minus decay occurs, the smaller force of electrostatic repulsion allows the nucleus to drop into a lower energy state. Metastable isotopes present a challenge as their unusual spin states make it difficult for them to emit a photon and reach a lower energy state due to
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21joanna12
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I thought I would ask this question in the quantum mechanics section as I presume it has something to do with QM, like the reason why alpha and beta decay do not happen immediately but instead there is a half life for this decay. My understanding is that with alpha decay, the strong nuclear force means that the energy required for the alpha decay is more than the nucleus has available, so you need quantum tunnelling for this to occur, which has a definite probability of happening. This gives rise to a half-life. When it comes to beta minus decay, I think that the nucleus is in a higher energy state when you have the extra proton due to repulsion of protons, and the nucleus does not have sufficient energy to go into this higher energy state classically, but with quantum tunnelling it can do this. Once it has gotten into this 'higher energy state', it actually becomes a lower energy state due to the Pauli exclusion principle. With regards to beta plus decay, I presume that the energy barrier is due to the Pauli exclusion principle but it drops into a lower energy state once beta minus decay has occurred due to the smaller force of electrostatic repulsion. But with metastable isotopes I am have absolutely no idea. I just don't understand what could be preventing an isotope from emitting a photon to drop into a lower energy state.

Please correct me if something I have said is completely wrong! Thank you in advance for any replies! :)
 
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Metastable isotopes offen have unsual spin states - emitting a single photon to reach another state is "problematic" in terms of angular momentum conservation. To find another analogy here, the photon might have to get so much angular momentum it cannot come from inside the nucleus.
 
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1. How can metastable isotopes exist?

Metastable isotopes exist due to the process of nuclear isomerism, in which the nucleus of an atom is in an excited state and has a longer lifetime than a regular excited state. This allows the isotope to remain in a metastable state for a longer period of time.

2. What causes an isotope to become metastable?

An isotope becomes metastable when it undergoes a nuclear reaction, such as alpha or beta decay, and is left in an excited state. This can also occur through the absorption of a neutron or gamma ray.

3. How do scientists identify and study metastable isotopes?

Scientists use various methods such as mass spectrometry and gamma ray spectroscopy to identify and study metastable isotopes. These techniques allow for the detection of the isotope's unique properties and behaviors.

4. Can metastable isotopes be artificially created?

Yes, metastable isotopes can be artificially created through the process of nuclear reactions in a laboratory setting. This allows scientists to study and manipulate these isotopes for various research purposes.

5. What are the practical applications of metastable isotopes?

Metastable isotopes have various practical applications in fields such as nuclear medicine, nuclear energy, and materials science. They can also be used as tracers in chemical reactions and in the production of radiopharmaceuticals.

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