Abstract
An analysis of the astrophysical factor of the proton-proton weak capture () is performed on a large energy range covering solar-core and early Universe temperatures. The measurement of being physically unachievable, its value relies on the theoretical calculation of the matrix element . Surprisingly, reaches a maximum near that has been unexplained until now. A model-independent parametrization of valid up to about is established on the basis of recent effective-range functions. It provides an insight into the relationship between the maximum of and the proton-proton resonance pole at from analytic continuation. In addition, this parametrization leads to an accurate evaluation of the derivatives of , and hence of , in the limit of zero energy.
2 More- Received 10 February 2019
- Revised 15 May 2019
DOI:https://doi.org/10.1103/PhysRevC.100.035805
©2019 American Physical Society