TY - JOUR
T1 - Properties of Na20, Al24, P28, Cl32, and K36 for studies of explosive hydrogen burning
AU - Wrede, C.
AU - Clark, J. A.
AU - Deibel, C. M.
AU - Faestermann, T.
AU - Hertenberger, R.
AU - Parikh, A.
AU - Wirth, H. F.
AU - Bishop, S.
AU - Chen, A. A.
AU - Eppinger, K.
AU - Freeman, B. M.
AU - Krücken, R.
AU - Lepyoshkina, O.
AU - Rugel, G.
AU - Setoodehnia, K.
PY - 2010/9/29
Y1 - 2010/9/29
N2 - The radiative proton-capture reactions Ne19(p,γ)Na20, Mg23(p,γ)Al24, Si27(p,γ)P28, S31(p,γ)Cl32, and Ar35(p,γ)K36 potentially influence energy generation and/or nucleosynthesis during explosive hydrogen burning in classical novae and/or type I x-ray bursts. The thermonuclear rates of these reactions are dependent on resonance energies Er=Ex-Q and strengths ωγ. The Ne20(He3,t)Na20, Mg24(He3,t)Al24, Si28(He3,t)P28, S32(He3,t)Cl32, and Ar36(He3,t)K36 reactions have been measured using a 32-MeV, He32+ beam; ion-implanted carbon-foil targets developed at the University of Washington; and the Munich Q3D magnetic spectrograph. This experiment has already yielded precision mass measurements of Na20, Al24, P28, and Cl32 [C. Wrede, Phys. Rev. CPRVCAN0556-281310.1103/PhysRevC.81.055503 81, 055503 (2010)], which are used presently to constrain the corresponding (p,γ) reaction Q values. The new Al24 and P28 masses resolve a discrepancy in the energy of the lowest-energy resonance in the Mg23(p,γ)Al24 reaction and better constrain a direct measurement of its strength. Excitation energies in Cl32 and K36 have also been measured. An important new proton-unbound level has been found at Ex=2196.9(7) keV in K36 and the uncertainties in K36 excitation energies have been reduced by over an order of magnitude. Using the new data on K36, the A=36, T=1 triplets have been reassigned. The thermonuclear Ar35(p,γ)K36 reaction rate is found to be much higher than a commonly adopted rate and this could affect energy generation in type I x-ray bursts.
AB - The radiative proton-capture reactions Ne19(p,γ)Na20, Mg23(p,γ)Al24, Si27(p,γ)P28, S31(p,γ)Cl32, and Ar35(p,γ)K36 potentially influence energy generation and/or nucleosynthesis during explosive hydrogen burning in classical novae and/or type I x-ray bursts. The thermonuclear rates of these reactions are dependent on resonance energies Er=Ex-Q and strengths ωγ. The Ne20(He3,t)Na20, Mg24(He3,t)Al24, Si28(He3,t)P28, S32(He3,t)Cl32, and Ar36(He3,t)K36 reactions have been measured using a 32-MeV, He32+ beam; ion-implanted carbon-foil targets developed at the University of Washington; and the Munich Q3D magnetic spectrograph. This experiment has already yielded precision mass measurements of Na20, Al24, P28, and Cl32 [C. Wrede, Phys. Rev. CPRVCAN0556-281310.1103/PhysRevC.81.055503 81, 055503 (2010)], which are used presently to constrain the corresponding (p,γ) reaction Q values. The new Al24 and P28 masses resolve a discrepancy in the energy of the lowest-energy resonance in the Mg23(p,γ)Al24 reaction and better constrain a direct measurement of its strength. Excitation energies in Cl32 and K36 have also been measured. An important new proton-unbound level has been found at Ex=2196.9(7) keV in K36 and the uncertainties in K36 excitation energies have been reduced by over an order of magnitude. Using the new data on K36, the A=36, T=1 triplets have been reassigned. The thermonuclear Ar35(p,γ)K36 reaction rate is found to be much higher than a commonly adopted rate and this could affect energy generation in type I x-ray bursts.
UR - http://www.scopus.com/inward/record.url?scp=77957322925&partnerID=8YFLogxK
U2 - 10.1103/PhysRevC.82.035805
DO - 10.1103/PhysRevC.82.035805
M3 - Article
AN - SCOPUS:77957322925
SN - 0556-2813
VL - 82
JO - Physical Review C - Nuclear Physics
JF - Physical Review C - Nuclear Physics
IS - 3
M1 - 035805
ER -