Low energy resonances inN15(α,γ)19

Charged-particle thermonuclear reaction rates: II. Tables and graphs of reaction rates and probability density functions

“…For those we use results from α-particle transfer experiments to 19 F mirror states [166,58] and assume, as in Fisker et al [91], the equality of reduced α-particle Reaction rate ratio widths between mirror levels. This hypothesis has been questioned [59] because of an apparent disagreement [253] between the reduced α-particle widths of the 849 keV resonance (as derived from the total width and the α-particle branching ratio [164]) and of the corresponding 19 F mirror state (as obtained from a 15 N( 7 Li,t) 19 F transfer experiment [58]). However, a new measurement [57] of the α-particle branching ratio has not confirmed this disagreement: for the first two resonances the measured α-particle branching ratios [57,226] are compatible with the Γ α values deduced from transfer reactions.…”

Comparison of low-energy resonances in15N(α,γ)19F andOliveira1, Coc2, Aguer3 et al. 1997Phys. Rev. CSelf Cite370160View full textAdd to dashboardCite

“…In all these transfer experiments it was shown that the reactions were essentially direct. Some discrepancies between the results presented in these papers have been stated [1].…”

“…However, in the case of the E x =5.107 MeV level, unbound by ≈1.1 MeV this approximation is questionable. On the contrary,Table Ishows a reasonable agreement for the low lying levels when comparison is possible.In addition, for the 4.378 MeV level, Wilmes et al[1] pointed out an apparent contradiction between the value Γ α deduced from the alpha-transfer experiment on 15 N and a value deduced from the ratio Γ α /Γ obtained by Magnus et al…”

“…]: the previous value was determined from an experiment by Magnus et al[3], the new value is the result of the absolute determination. )For both levels E x =4.550 MeV and E x =4.683 MeV the agreement between the alphatransfer[4] and the alpha-capture results[1,3,15,16] is good within a factor of 2. But in the This last point is likely the source of the discrepancy since the FR-DWBA analysis was performed by de Oliveira et alwithin the approximation that the relevant levels are bounds.…”

“…The argument of Wilmes et al [1] is that both levels belong to the same K π =3/2 + band and have the same cluster structure: 12 MeV levels a comparison between experimental results of alpha transfer [4] and alpha capture [1,15,16] is possible. The comparison is made in Table I, column 5,7 and 10.…”