Curiosity☉ Sun
If 3He(α,γ)7Be were twice as fast, this model of the Sun's centre would end up with about two fifths more beryllium‑7 (+37%).
- Energy output +12%; the first 1% of the hydrogen burns 14% sooner.
Beryllium‑7 gives off the Sun's 7Be neutrinos, which Borexino counted on Earth.
One-zone model at 16 MK over 1 billion years. Real stars adjust. The energy is that of this gas at the model's temperature, not the star's luminosity: a real star would adjust its temperature to keep its luminosity. Doubling is a what-if, not the rate's actual uncertainty. How well this rate is known: improving.