Proton capture by 15N at stellar energies

doi:10.1016/0375-9474(74)90205-X

Nuclear Physics A

Volume 235, Issue 2, 16 December 1974, Pages 450-459

https://doi.org/10.1016/0375-9474(74)90205-X Get rights and content

Abstract

Excitation functions of the ¹⁵N(p, γ)¹⁶O proton capture reaction have been obtained at θ_γ = 45° and E_p = 150–2500 keV. Below E_p = 400 keV, the reaction is dominated by capture into the ground state of ¹⁶O. The observed excitation function for the latter process can be explained if, in addition to the two well-known J^π = 1⁻ resonances at E_p = 338 and 1028 keV, a direct radiative capture process (DC → 0) is included in the analysis. The direct capture component in the capture reaction is enhanced through interference effects on the tails of the two resonances. From the observed direct capture cross section, a single-particle spectroscopic factor of C²S(1p) = 1.8 ± 0.4 has been deduced for the ground state in ¹⁶O. The extrapolated astrophysical S-factor of S(0) = 64 ± 6 keV · b for the ¹⁵N(p, γ₀)¹⁶O reaction is a factor of 2.5 larger than previously reported. This result amplifies the role of the oxygen side cycle in the CNO hydrogen burning process.

The observed excitation function of the ¹⁵N(p, α₁γ₁)¹²C reaction at E_p = 150 – 2500 keV shows that this reaction makes a negligible contribution to hydrogen burning at stellar energies [S(0) ≈ 0.1 keV · b] compared to $^{15} N (p, γ_{0})^{16} O and^{15} N (p, α_{o})^{12} C$ .

References (26)

C. Rolfs
Nucl. Phys.
(1973)
F. Ajzenberg-Selove
Nucl. Phys.
(1971)
C. Rolfs et al.
Gamma-rays from capture reactions
H.P. Trautvetter
S. Bashkin et al.
Phys. Rev.
(1959)
G.J. Vanbraet et al.
Nucl. Phys.
(1966)
M. Stroetzel
Z. Phys.
(1968)
A.P. Zuker
Phys. Rev. Lett.
(1968)
C. Rolfs et al.
Nucl. Phys.
(1973)
J.B. Marion et al.
Phys. Rev.
(1967)
G. Morpurgo
Phys. Rev.
(1958)
G. Morpurgo
Phys. Rev.
(1959)

E.M. Burbidge et al.

Rev. Mod. Phys.

(1957)

H.A. Bethe

Phys. Rev.

(1939)

H.A. Bethe

Phys. Rev.

(1939)

C.F. von Weizsäcker

Z. Phys.

(1937)

C.F. von Weizsäcker

Z. Phys.

(1939)

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^☆: Supported in part by the National Science Foundation [GP-28027].

^††: Present address: Kernphysikalishes Institut, Universitát Múnster, Germany.

^†††: On leave from the National Science Foundation, Washington, DC.

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Nuclear Physics A

Abstract

References (26)

Nucl. Phys.

Nucl. Phys.

Gamma-rays from capture reactions

Phys. Rev.

Nucl. Phys.

Z. Phys.

Phys. Rev. Lett.

Nucl. Phys.

Phys. Rev.

Phys. Rev.

Phys. Rev.

Rev. Mod. Phys.

Phys. Rev.

Phys. Rev.

Z. Phys.

Z. Phys.

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LUNA: Status and prospects

About Nuclear Resonant Reaction Analysis for Hydrogen Investigations in Amorphous Silicon

NACRE II: An update of the NACRE compilation of charged-particle-induced thermonuclear reaction rates for nuclei with mass number A > 16

Study of the neutron and proton capture reactions <sup>10,11</sup>B(n, γ), <sup>11</sup>B(p, γ), <sup>14</sup>C(p, γ), and <sup>15</sup>N(p, γ) at thermal and astrophysical energies

Astrophysical S-factor and reaction rate for <sup>15</sup>N(p,γ)<sup>16</sup>O within the modified potential cluster model

The astrophysical S−factor and reaction rate for <sup>15</sup>N(p,γ)<sup>16</sup>O within the modified potential cluster model

Proton capture by 15N at stellar energies☆

Abstract

Nucl. Phys.

Nucl. Phys.

Phys. Rev.

Nucl. Phys.

Z. Phys.

Phys. Rev. Lett.

Nucl. Phys.

Phys. Rev.

Phys. Rev.

Phys. Rev.

Rev. Mod. Phys.

Phys. Rev.

Phys. Rev.

Z. Phys.

Z. Phys.

Proton capture by ¹⁵N at stellar energies☆