What is the approximate core temperature required to initiate sustained nuclear fusion in a protostar?

Answer

15 million Kelvin

The protostar phase ends when the core temperature reaches approximately 15 million Kelvin, at which point the electrostatic repulsion between hydrogen nuclei is overcome, allowing the proton-proton chain reaction to start.

What is the approximate core temperature required to initiate sustained nuclear fusion in a protostar?
star formationastrophysicsprotostarsstellar physicsheat generation