Astrophysical $S$ factor for the ${}^{15}{\rm N}(p,γ){}^{16}{\rm O}$ reaction from $R$-matrix analysis and asymptotic normalization coefficient for ${}^{16}{\rm O} \to {}^{15}{\rm N} + p$. Is any fit acceptable?

Details Astrophysical $S$ factor for the ${}^{15}{\rm N}(p,γ){}^{16}{\rm O}$ reaction from $R$-matrix analysis and asymptotic normalization coefficient for ${}^{16}{\rm O} \to {}^{15}{\rm N} + p$. Is any fit acceptable? Astrophysical $S$ factor for the ${}^{15}{\rm N}(p,γ){}^{16}{\rm O}$ reaction from $R$-matrix analysis and asymptotic normalization coefficient for ${}^{16}{\rm O} \to {}^{15}{\rm N} + p$. Is any fit acceptable?

2011-01-10

arxiv.org/abs/1101.1924v1

Phys.Rev.C83:044604,2011

Physics

Nuclear Physics

Nuclear Experiment

Submitted to PRC

Scientific paper

10.1103/PhysRevC.83.044604

The $^{15}{\rm N}(p,\gamma)^{16}{\rm O}$ reaction provides a path from the CN cycle to the CNO bi-cycle and CNO tri-cycle. The measured astrophysical factor for this reaction is dominated by resonant capture through two strong $J^{\pi}=1^{-}$ resonances at $E_{R}= 312$ and 962 keV and direct capture to the ground state. Recently, a new measurement of the astrophysical factor for the $^{15}{\rm N}(p,\gamma)^{16}{\rm O}$ reaction has been published [P. J. LeBlanc {\it et al.}, Phys. Rev. {\bf C 82}, 055804 (2010)]. The analysis has been done using the $R$-matrix approach with unconstrained variation of all parameters including the asymptotic normalization coefficient (ANC). The best fit has been obtained for the square of the ANC $C^{2}= 539.2$ fm${}^{-1}$, which exceeds the previously measured value by a factor of $\approx 3$. Here we present a new $R$-matrix analysis of the Notre Dame-LUNA data with the fixed within the experimental uncertainties square of the ANC $C^{2}=200.34$ fm${}^{-1}$. Rather than varying the ANC we add the contribution from a background resonance that effectively takes into account contributions from higher levels. Altogether we present 8 fits, five unconstrained and three constrained. In all the fits the ANC is fixed at the previously determined experimental value $C^{2}=200.34$ fm${}^{-1}$. For the unconstrained fit with the boundary condition $B_{c}=S_{c}(E_{2})$, where $E_{2}$ is the energy of the second level, we get $S(0)=39.0 \pm 1.1 $ keVb and normalized ${\tilde \chi}^{2}=1.84$, i.e. the result which is similar to [P. J. LeBlanc {\it et al.}, Phys. Rev. {\bf C 82}, 055804 (2010)]. From all our fits we get the range $33.1 \leq S(0) \leq 40.1$ keVb which overlaps with the result of [P. J. LeBlanc {\it et al.}, Phys. Rev. {\bf C 82}, 055804 (2010)]. We address also physical interpretation of the fitting parameters.

Affiliated with

Also associated with

No associations

Rating

Astrophysical $S$ factor for the ${}^{15}{\rm N}(p,γ){}^{16}{\rm O}$ reaction from $R$-matrix analysis and asymptotic normalization coefficient for ${}^{16}{\rm O} \to {}^{15}{\rm N} + p$. Is any fit acceptable? does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Astrophysical $S$ factor for the ${}^{15}{\rm N}(p,γ){}^{16}{\rm O}$ reaction from $R$-matrix analysis and asymptotic normalization coefficient for ${}^{16}{\rm O} \to {}^{15}{\rm N} + p$. Is any fit acceptable?, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Astrophysical $S$ factor for the ${}^{15}{\rm N}(p,γ){}^{16}{\rm O}$ reaction from $R$-matrix analysis and asymptotic normalization coefficient for ${}^{16}{\rm O} \to {}^{15}{\rm N} + p$. Is any fit acceptable? will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-457430