137 citations · 1.3k across the 43 of their papers we have counts for
29 papers · 1 filter
Impact of Sub-2.5 MeV 12C+12CResonances on the Production of Elements from C to Pd in Core-Collapse Supernovae
L. Roberti, S. Palmerini, A. Falla +10
We explore the impact of a more efficient 12C+12C reaction on the structure and nucleosynthesis of massive stars. We calculate non-rotating stellar models with initial masses of 15…
s-process nucleosynthesis in low-mass AGB stars by the C(,n)O neutron source
Inma Domínguez, Carlos Abia, Maurizio Busso +2
In this review we outline our knowledge on slow neutron captures, concentrating on its main part occurring during the final stages of stellar evolution for low or intermediate-mass…
Oxygen and Aluminum-Magnesium Isotopic Systematics of Presolar Nanospinel Grains from CI Chondrite Orgueil
Nan Liu, Nicolas Dauphas, Sergio Cristallo +2
Presolar oxide grains have been previously divided into several groups (Group 1 to 4) based on their isotopic compositions, which can be tied to several stellar sources. Much of av…
New Multielement Isotopic Compositions of Presolar SiC Grains: Implications for Their Stellar Origins
Nan Liu, Jens Barosch, Larry R. Nittler +5
We report NanoSIMS Si and Mg-Al isotopic data (and C, N, and Ti isotopic data when available) for 85 submicron- to micron-sized presolar SiC grains from the CM2 Murchison meteorite…
Theoretical estimate of the half-life for the radioactive Cs and Cs in astrophysical scenarios
S. Taioli, D. Vescovi, M. Busso +4
We analyze the CsBa and CsBa decays, which are crucial production channels for Ba isotopes in Asympt…
Presolar grain isotopic ratios as constraints to nuclear and stellar parameters of AGB nucleosynthesis
Sara Palmerini, Maurizio Busso, Diego Vescovi +8
Recent models for evolved Low Mass Stars (with ), undergoing the AGB phase assume that magnetic flux-tube buoyancy drives the formation of C reservoirs…
Magnetic-buoyancy-induced mixing in AGB Stars: fluorine nucleosynthesis at different metallicities
D. Vescovi, S. Cristallo, S. Palmerini +2
Asymptotic giant branch (AGB) stars are considered to be among the most significant contributors to the fluorine budget in our Galaxy. While at close-to-solar metallicity observati…
The impact of the new measurement of the fusion cross section on the final compactness of the massive stars
Alessandro Chieffi, Lorenzo Roberti, Marco Limongi +6
We discuss how the new measurement of the fusion cross section carried out with the Trojan Horse Method (Tumino, A., Spitaleri, C., La Cognata, M., et al., 2018, Na…
s-Processing in AGB Stars Revisited. III. Neutron captures from MHD mixing at different metallicities and observational constraints
Maurizio Busso, Diego Vescovi, Sara Palmerini +2
We present post process neutron capture computations for Asymptotic Giant Branch stars of 1.5 to 3 Mo and metallicities -1.3 to 0.1. The reference stellar models are computed with…
The effects of a revised Be e-capture rate on solar neutrino fluxes
D. Vescovi, L. Piersanti, S. Cristallo +5
The electron-capture rate on Be is the main production channel for Li in several astrophysical environments. Theoretical evaluations have to account for not only the nuclea…
On the Origin of the Early Solar System Radioactivities. Problems with the AGB and Massive Star Scenarios
D. Vescovi, M. Busso, S. Palmerini +7
Recent improvements in stellar models for intermediate-mass and massive stars are recalled, together with their expectations for the synthesis of radioactive nuclei of lifetime $τ\…
The importance of the 13C(alpha,n)16O reaction in Asymptotic Giant Branch stars
S. Cristallo, M. La Cognata, C. Massimi +9
Low mass Asymptotic Giant Branch stars are among the most important polluters of the interstellar medium. In their interiors, the main component (A>90) of the slow neutron capture…
s-Processing from MHD-induced mixing and isotopic abundances in presolar SiC grains
S. Palmerini, O. Trippella, M. Busso +4
In the past years the observational evidence that s-process elements from Sr to Pb are produced by stars ascending the socalled Asymptotic Giant Branch (or AGB) could not be explai…
A Deep Mixing Solution to the Aluminum and Oxygen Isotope Puzzles in Presolar Grains
Sara Palmerini, Oscar Trippella, Maurizio Busso
We present here the application of a model for a mass circulation mechanism in between the H-burning shell and the base of the convective envelope of low mass AGB stars, aimed at s…
-Processing in AGB Stars Revisited. II. Enhanced C Production Through MHD-Induced Mixing
O. Trippella, M. Busso, S. Palmerini +2
Slow neutron captures are responsible for the production of about of elements heavier than iron, mainly, occurring during the asymptotic giant branch phase of low-mass stars…
s-Processing in AGB Stars Revisited. I. Does the Main Component Constrain the Neutron Source in the 13C-Pocket?
O. Trippella, M. Busso, E. Maiorca +2
Slow neutron captures at A 85 are mainly guaranteed by the reaction 13C(,n)16O in AGB stars, requiring proton injections from the envelope. These were so far assumed to…
AGB stars and presolar grains
M. Busso, O. Trippella, E. Maiorca +1
Among presolar materials recovered in meteorites, abundant SiC and AlO grains of AGB origins were found. They showed records of C, N, O, Al and s-element isotopi…
Nitrogen isotopes in AGB carbon stars and presolar SiC grains: a challenge for stellar nucleosynthesis
R. Hedrosa, C. Abia, M. Busso +5
Isotopic ratios of C, N, Si, and trace heavy elements in presolar SiC grains from meteorites provide crucial constraints to nucleosynthesis. A long-debated issue is the origin of t…
Theoretical Estimates of Stellar e-Captures. I. The half-life of 7Be in Evolved Stars
Stefano Simonucci, Simone Taioli, Maurizio Busso +1
The Li enrichment in the Universe still presents various puzzles to astrophysics. One open issue is that of obtaining estimates for the rate of e-captures on 7Be, for T and rho con…
Carbon and oxygen isotopic ratios in Arcturus and Aldebaran: Constraining the parameters for non convective mixing on the RGB
C. Abia, S. Palmerini, M. Busso +1
We re-analysed the carbon and oxygen isotopic ratios in the atmospheres of the two bright K giants Arcturus and Aldebaran. Previous determinations of their 16O/18O ratios showed a…
Lithium destruction and production observed in red giant stars
Stefan Uttenthaler, Thomas Lebzelter, Maurizio Busso +3
According to standard stellar evolution, lithium is destroyed throughout most of the evolution of low- to intermediate-mass stars. However, a number of evolved stars on the red gia…
News on the s process from young open clusters
Enrico Maiorca, Laura Magrini, Maurizio Busso +3
Recent spectroscopic measurements in open clusters younger than the Sun, with [Fe/H]>=0, showed that the abundances of neutron-rich elements have continued to increase in the Galax…
Revision of the 15N(p,γ)16O reaction rate and oxygen abundance in H-burning zones
A. Caciolli, C. Mazzocchi, V. Capogrosso +27
The NO cycle takes place in the deepest layer of a H-burning core or shell, when the temperature exceeds T {\simeq} 30 {\cdot} 106 K. The O depletion observed in some globular clus…
Deep Mixing in Evolved Stars. II. Interpreting Li Abundances in RGB and AGB Stars
S. Palmerini, S. Cristallo, M. Busso +4
We reanalyze the problem of Li abundances in red giants of nearly solar metallicity. After an outline of the problems affecting our knowledge of the Li content in low-mass stars (M…