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arXiv · 0801.4330

Proton-proton fusion in pionless effective theory

S. Ando·J. W. Shin·C. H. Hyun·S. W. Hong·K. Kubodera
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Abstract

The proton-proton fusion reaction, $pp\to de^+ν$, is studied in pionless effective field theory (EFT) with di-baryon fields up to next-to leading order. With the aid of the di-baryon fields, the effective range corrections are naturally resummed up to the infinite order and thus the calculation is greatly simplified. Furthermore, the low-energy constant which appears in the axial-current-di-baryon-di-baryon contact vertex is fixed through the ratio of two- and one-body matrix elements which reproduces the tritium lifetime very precisely. As a result we can perform a parameter free calculation for the process. We compare our numerical result with those from the accurate potential model and previous pionless EFT calculations, and find a good agreement within the accuracy better than 1%.

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S. Ando, J. W. Shin, C. H. Hyun, S. W. Hong, K. Kubodera. 2008-01-28. Proton-proton fusion in pionless effective theory. https://doi.org/10.1016/j.physletb.2008.08.040

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