Publications by authors named "Rapagnani D"
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.
Article Synopsis
- - Understanding the decay properties of the Hoyle state in carbon nuclei is crucial for calculating how much carbon is produced in red-giant stars.
- - This paper presents a new, nearly background-free method to measure the decay ratio of the Hoyle state, utilizing advanced techniques for detecting charged particles.
- - The study introduces a bidimensional map to improve measurement accuracy, providing a significant value for the radiative branching ratio and addressing discrepancies from recent research findings.
Article Synopsis
- 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.
One of the main neutron sources for the astrophysical s process is the reaction ^{13}C(α,n)^{16}O, taking place in thermally pulsing asymptotic giant branch stars at temperatures around 90 MK. To model the nucleosynthesis during this process the reaction cross section needs to be known in the 150-230 keV energy window (Gamow peak). At these sub-Coulomb energies, cross section direct measurements are severely affected by the low event rate, making us rely on input from indirect methods and extrapolations from higher-energy direct data.
View Article and Find Full Text PDFFlowing plasma jets are increasingly investigated and used for surface treatments, including biological matter, and as soft ionization sources for mass spectrometry. They have the characteristic capability to transport energy from the plasma excitation region to the flowing afterglow, and therefore to a distant application surface, in a controlled manner. The ability to transport and deposit energy into a specimen is related to the actual energy transport mechanism.
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