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In Wolf-Rayet and asymptotic giant branch (AGB) stars, the 26gAl(p,γ)27 Si reaction is expected to govern the destruction of the cosmic γ-ray emitting nucleus 26Al. The rate of this reaction, however, is highly uncertain due to the unknown properties of key resonances in the temperature regime of hydrogen burning. We present a high-resolution inverse kinematic study of the 26gAl(d,p)27Si reaction as a method for constraining the strengths of key astrophysical resonances in the 26gAl(p,γ)27Si reaction. In particular, the results indicate that the resonance at Er = 127keV in determines the entire 26gAl(p,γ)27Si reaction rate over almost the complete temperature range of Wolf-Rayet stars and AGB stars. [ABSTRACT FROM AUTHOR]

We report here a determination of the asymptotic normalization coefficient of the valence neutron in 8Li from a measurement of the angular distribution of the 7Li(8Li,7Li)8Li reaction at 11 MeV. Using isospin symmetry the 8B ANC has also been calculated and used to infer a value for S17(0) of 20.2 ± 4.4 eV b. [ABSTRACT FROM AUTHOR]

In stars, 16O represents the endpoint of the helium burning sequence due to the low rate of 16O(α,γ)20Ne. We present a new direct measurement of the total cross section of 16O(α,γ)20Ne at Ec.m. = 1.69 MeV employing the DRAGON recoil separator. In addition, the branching ratios and strength of the Ec.m. = 2.426 MeV 3- resonance were determined. [ABSTRACT FROM AUTHOR]

The 18Ne(α,p)21Na reaction provides one of the main HCNO-breakout routes into the rp process in x-ray bursts. The 18Ne(α,p0)21Na reaction cross section has been determined for the first time in the Gamow energy region for peak temperatures 7 ∼ 2 GK by measuring its time-reversal reaction 21Ne(p,α)18Ne in inverse kinematics. The astrophysical rate for ground-state to ground-state transitions was found to be a factor of 2 lower than Hauser-Feshbach theoretical predictions. Our reduced rate will affect the physical conditions under which breakout from the HCNO cycles occurs via the 18Ne(p,α)21Na reaction. [ABSTRACT FROM AUTHOR]

The 17O(p,γ)18F reaction plays an important role in hydrogen-burning nucleosynthesis. Conflicting values for the low-energy behavior of its cross section exist in the literature. We present direct measurements of the astrophysical S factor of the 17O(p,γ)18F reaction at center-of-mass energies between 250 and 500 keV. These measurements were conducted in inverse kinematics at the DRAGON recoil separator. [ABSTRACT FROM AUTHOR]

This Letter reports a study of the highly debated 10Li structure through the d(9Li, p)10Li one-neutron transfer reaction at 100 MeV. The 10Li energy spectrum is measured up to 4.6 MeV and angular distributions corresponding to different excitation energy regions are reported for the first time. The comparison between data and theoretical predictions, including pairing correlation effects, shows the existence of a p1/2 resonance at 0.45 ± 0.03 MeV excitation energy, while no evidence for a significant s-wave contribution close to the threshold energy is observed. Moreover, two high-lying structures are populated at 1.5 and 2.9 MeV. The corresponding angular distributions suggest a significant s1/2 partial-wave contribution for the 1.5 MeV structure and a mixing of configurations at higher energy, with the d5/2 partial-wave contributing the most to the cross section. [ABSTRACT FROM AUTHOR]