The first step in all the branches is the fusion of two protons into a deuteron. As the protons fuse, one of them undergoes beta plus decay, converting into a neutron by emitting a positron and an electron neutrino [7] (though a small amount of deuterium nuclei is produced by the "pep" reaction, see below):

The energy from the Sun - both heat and light energy - originates from a nuclear fusion process that is occurring inside the core of the Sun. The specific type of fusion that occurs inside of the Sun is known as proton-proton fusion.

In the proton-proton fusion process, deuterium is produced by the weak interaction in a quark transformation which converts one of the protons to a neutron. The neutrinos quickly escape the sun, requiring only about 2 seconds to exit the sun compared to perhaps a million years for a photon to traverse from the center to the surface of the sun.

A fusion reaction occurs when two lighter atomic nuclei fuse together to form a heavier nucleus. The most simple fusion reaction occurs when a single proton, the most basic positive electric charge, is fused to a second proton. This is the first step in the fusion process that makes energy in the heart of our Sun.

Mar 6, 2021 · As far as I know, a proton turns into a neutron by emitting a positron. How does that work? Shouldn't a proton be slightly lighter than a neutron? This seems to violate the laws of thermodynamics. A positron can't have negative mass either. This produces energy while increasing its own mass and also violates pair production.

How do we turn hydrogen into helium and make energy? The process is called the Proton-Proton (PP) Chain, and it operates inside the Sun and stars of similar mass. Step 1: Smash two protons together to make deuterium. Do Steps 1 and 2 again, so that we have two helium-3 nuclei. Then (69% of the time):

In Handout ix we wrote down a reaction for the fusion of four hydro-gen nuclei into one helium nucleus (see eqn. 5, ibid.). In this reaction there are a sequence of intermediate steps that we’re now going to examine in detail. The simplest sequence, known as the proton-proton (pp) chain, be-gins with the interaction of a proton with another ...

Proton-proton chain, chain of thermonuclear reactions that is the chief source of energy radiated by the Sun and other cool main-sequence stars. Four hydrogen nuclei are combined to form one helium nucleus; 0.7 percent of the original mass is lost mainly by conversion into energy.

There are two sequences of reactions that can convert hydrogen to helium and thereby release energy that are important in stars. The Proton-Proton or PP Chain, which is important in stars the mass of the Sun and less. We discuss the PP chain in this section and the CNO cycle in the next.

Nov 20, 2024 · The Proton-Proton Cycle is for less-massive stars, like the sun. Eighty-five percent of the sun’s energy comes from this type of reaction; other reactions include: A He-3 atom and a He-4 atom combine to form a beryllium-7 (4p + + 3n 0 ) and a γ