Proton beta plus decay -proton proton chain

In summary, beta-plus decay, also known as proton beta plus decay, occurs when a proton decays into a neutron, emitting a beta particle and an electron neutrino. This process is possible due to the binding energy of the nucleus, which allows for the conversion of a proton into a neutron. The increase in binding energy also explains the mass difference between the parent and daughter nuclei. Additionally, the ratio of protons to neutrons in a nucleus plays a role in determining its stability and the type of decay it undergoes.
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proton beta plus decay --proton proton chain

Im a biologist so forgive the ignorance.

In beta-plus decay, a proton decays into a neutron and emmits a β+ and an electron neutrino. If the neutron is more massive than the proton where did the extra mass come from?

Im asking in the context of the proton-proton chain. The first step in the stellar core creates a di-proton that decays (rarely) into a deuterium (more massive than the di-proton), and emits a β+ and an electron neutrino (both have mass). So, the reaction actually emits massive particles and still produces a more massive end product. what am I missing that explains how this happens? do vacuum fluctuations contribute this mass increase? is the radius of a neutron larger than a proton? providing more "room" for vacuum fluctuations, or do quarks alone account for the mass difference?

And, I have heard the "we are all stardust" and "stars are reactors that build heavier atoms" anecdotes. But, because free neutrons decay into protons, and since neutrons are needed to create the more massive atoms that known life requires, isn't it more correct to say that stars produce neutrons? granted they are in nuclei, but still, does my point register? yes they build heavier elements, especially in their deaths, but main sequence stars are really building neutrons. right?
 
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In beta-plus decay, a proton decays into a neutron and emmits a β+ and an electron neutrino. If the neutron is more massive than the proton where did the extra mass come from?
From the binding energy of the nucleus. You have to take into count the entire mass of the parent and daughter nuclei, not just the one proton and neutron. The mass of a nucleus is less than the sum of the masses of the protons and neutrons that make it up. This difference is called the binding energy.

Nuclei prefer to have a certain ratio of protons to neutrons. The nuclei with this ratio have the greatest binding energy and are the most stable. This is called the valley of stability. Nuclei with 'too many' protons are not as tightly bound, and they can increase their binding energy by turning a proton into a neutron (positron emission). Nuclei with 'too few' protons are also not as tightly bound, and they can increase their binding energy by turning a neutron into a proton (electron emission).

The increase in binding energy supplies the energy needed to make the decay possible.
 

1. What is proton beta plus decay?

Proton beta plus decay, also known as positron emission, is a nuclear reaction in which a proton in the nucleus of an atom converts into a neutron, emitting a positron and a neutrino in the process.

2. How does the proton beta plus decay contribute to the proton-proton chain?

In the proton-proton chain, the proton beta plus decay is the first step, where two protons fuse together to form a deuterium nucleus, releasing a positron and a neutrino. This deuterium nucleus then undergoes further reactions in the chain to eventually form a helium nucleus.

3. What is the difference between proton beta plus decay and proton beta minus decay?

The main difference between proton beta plus decay and proton beta minus decay is the charge of the particles emitted. In proton beta plus decay, a positron (positive charge) is emitted, while in proton beta minus decay, an electron (negative charge) is emitted.

4. Why is proton beta plus decay important in nuclear fusion reactions?

Proton beta plus decay plays a crucial role in the proton-proton chain, which is one of the main processes of energy production in stars. Without this decay, the chain would not be able to continue, and the fusion reactions would eventually stop.

5. Can proton beta plus decay be observed in experiments?

Yes, proton beta plus decay can be observed in experiments through the detection of the emitted positron and the energy released in the reaction. This decay is also used in medical imaging techniques such as positron emission tomography (PET).

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