Publications by authors named "R Menegazzo"
Article Synopsis
- The CNO cycle is a key nuclear energy process in stars, particularly significant in hydrostatic hydrogen burning at temperatures between 20 to 80 MK.
- This study reports the first direct measurements of the resonance strength of the ^{17}O(p,γ)^{18}F reaction, revealing a strength about twice as high as previously documented.
- The findings enhance our comprehension of oxygen isotopic ratios observed in red giant stars and in O-rich presolar grains, confirming consistency with earlier results from different reaction channels.
The excited states of unstable ^{20}O were investigated via γ-ray spectroscopy following the ^{19}O(d,p)^{20}O reaction at 8 AMeV. By exploiting the Doppler shift attenuation method, the lifetimes of the 2_{2}^{+} and 3_{1}^{+} states were firmly established. From the γ-ray branching and E2/M1 mixing ratios for transitions deexciting the 2_{2}^{+} and 3_{1}^{+} states, the B(E2) and B(M1) were determined.
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- The ^{12}C/^{13}C ratio is crucial for understanding how hydrogen burning occurs in stars and is influenced by specific nuclear reactions.
- Research conducted at LUNA in Italy has measured these reactions at previously unexplored low energy levels, contributing to our understanding of nucleosynthesis in giant stars.
- The team's findings indicate that their reaction rate results are significantly lower than most existing literature, providing a new, more precise estimate for the ^{12}C/^{13}C ratio during hydrogen burning.
Classical novae are thermonuclear explosions in stellar binary systems, and important sources of Al and Na. While γ rays from the decay of the former radioisotope have been observed throughout the Galaxy, Na remains untraceable. Its half-life (2.
View Article and Find Full Text PDFThe reduced transition probabilities for the 4_{1}^{+}→2_{1}^{+} and 2_{1}^{+}→0_{1}^{+} transitions in ^{92}Mo and ^{94}Ru and for the 4_{1}^{+}→2_{1}^{+} and 6_{1}^{+}→4_{1}^{+} transitions in ^{90}Zr have been determined in this experiment making use of a multinucleon transfer reaction. These results have been interpreted on the basis of realistic shell-model calculations in the f_{5/2}, p_{3/2}, p_{1/2}, and g_{9/2} proton valence space. Only the combination of extensive lifetime information and large scale shell-model calculations allowed the extent of the seniority conservation in the N=50 g_{9/2} orbital to be understood.
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