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Jakub Skowronski
All curiosities

Curiosity☉ Sun

If 1H(p,e+ν)2H were twice as fast, this model of the Sun's centre would end up with about a sixth less hydrogen (−15%).

  • Biggest knock-on effect: 3He (+26%).
  • Energy output +62%; the first 1% of the hydrogen burns 46% sooner.

The Sun's slowest step, never measured. A real Sun would cool down to compensate.

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: well known.

Try itHow we know this rate
Rate:
1H(p,e+ν)2H — G. R. Caughlan, W. A. Fowler (1988), ADNDT 40, 283, calculated from weak-interaction theory: p+p fusion has never been measured; REACLIB bet+
Well known:
The rate is known well enough for the stellar models that use it.
Model:
one-zone model; JINA REACLIB reaclib_default2_20250330, pynucastro 3.1.0; 2026-10-13