Approximately what core temperature must be reached for helium fusion to commence?

Answer

About $100$ million Kelvin ($10^8 ext{ K}$).

Fusing helium nuclei requires significantly more kinetic energy to overcome electrostatic repulsion compared to hydrogen fusion, necessitating the core temperature to climb substantially higher, typically reaching $10^8 ext{ K}$.

Approximately what core temperature must be reached for helium fusion to commence?
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