In: Physics
What is the very first step in the sequence of processes by which a main sequence star like our Sun derives its energy output, and about how long does it take for this first step to occur with 50% probability?
1. Weak decay of a proton to a neutron, positron and neutrino, in about 5 ×109 years.
3. Fusion of two He4 nuclei to form C8 , in about 1 year.
4. Fusion of a proton and neutron to form H2 , in about 0.01 second.
5. Fusion of a proton with He4 in about 0.1 second.
6. Fission of a He4 nucleus into two H2 nuclei.