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A new comprehensive analysis of nucleosynthesis in stars: a bridge between nuclear astrophysics, stellar models and observations.

Applicant Pignatari Marco
Number 148807
Funding scheme Ambizione
Research institution Departement Physik Universität Basel
Institution of higher education University of Basel - BS
Main discipline Astronomy, Astrophysics and Space Sciences
Start/End 01.09.2013 - 31.08.2014
Approved amount 130'617.00
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Keywords (6)

stars; nucleosynthesis; stellar evolution; nucleosynthesis; stars; stellar evolution

Lay Summary (Italian)

Lead
Gli elementi fondamentali per la vita come carbonio e ossigeno, o che ci sono famigliari nella vita di tutti i giorni come il ferro, l'argento e il piombo sono stati forgiati in stelle morte prima che il Sole si formasse, quasi cinque miliardi di anni fa. La comprensione di come tutti questi elementi si siano formati richiede di conoscere come le stelle nascono, evolvono e muoiono. I risultati ottenuti attraverso simulazioni di modelli stellari, possono essere confrontati con osservazioni spettroscopiche di stelle lontane. In antichi meteoriti sono state identificate polveri con abbondanze anomale rispetto al sole, e che si sono formate attorno ad altre stelle ormai morte. Quelle stelle non possono essere piu' osservate, ma si possono "toccare". La validita' dei risultati dei modelli stellari teorici possono essere confrontati con queste osservazioni, aiutandoci a capire come gli elementi si formano nelle stelle.
Lay summary

Soggetto e obiettivo


Lo scopo principale di questo progetto e' di avere una migliore comprensione di come gli elementi si formano nelle stelle. I due principali obbiettivi sono i seguenti: i) studio e comprensione delle abbondanze isotopiche misurate in polveri di origine presolare, formate in antiche esplosioni di supernovae di stelle massicce; ii) produzione di una nuova generazione di modelli stellari per stelle di massa piccola e intermedia (stelle fino a 7-8 volte piu' grandi del sole), dove l'impatto delle instabilita' convettive di Kelvin-Helmholtz e dovute a onde di gravita' vengano considerate nella produzione di elementi.


Contesto scientifico


Questo progetto permettera' di cambiare l'interpretazione delle abbondanze osservate in polveri ricche di carbonio formate in antiche supernovae. Mentre prima si pensava che queste erano dovute a una mescolanza di materia proveniente da diverse zone della stella esplosa, dimostreremo che invece le polveri mostrano abbondanze da una zone speci ca della stella. Questo permettera' di utilizzare correttamente queste osservazioni, quando vengono confrontate con le predizioni di modelli teorici. Le stelle piccole e intermedie danno un contributo fondamentale alla produzione di carbonio e azoto, e di elementi pesanti come il piombo. Questo progetto permettera' di capire meglio come queste stelle funzionano nelle ultime fasi della loro evoluzione, quando questi elementi vengono prodotti e mescolati in superficie.

Direct link to Lay Summary Last update: 10.04.2014

Responsible applicant and co-applicants

Employees

Publications

Publication
Barium Isotopic Composition of Mainstream Silicon Carbides from Murchison: Constraints for s-process Nucleosynthesis in Asymptotic Giant Branch Stars
Liu N., Savina M., Davis A., Gallino R., Straniero O., Gyngard F., Pellin M., Willingham M., Dauphas N., Pignatari M. (2014), Barium Isotopic Composition of Mainstream Silicon Carbides from Murchison: Constraints for s-process Nucleosynthesis in Asymptotic Giant Branch Stars, in The Astrophysical Journal, 786(1), 66.
A Born-Again AGB Star Origin of Type AB Silicon Carbide Grains Inferred from Radiogenic Sulfur-32
Fujiya W., Hoppe P., Zinner E., Pignatari M., Herwig F. (2014), A Born-Again AGB Star Origin of Type AB Silicon Carbide Grains Inferred from Radiogenic Sulfur-32, in 45th Lunar and Planetary Science Conference, 1777, 1515.
Chemical abundances in bright giants of the globular cluster M62 (NGC 6266)
Yong D., Alves Brito A., Da Costa G., Alonso Garcia J., Karakas A., Pignatari M., et al.... (2014), Chemical abundances in bright giants of the globular cluster M62 (NGC 6266), in Monthly Notices of the Royal Astronomical Society, 439(3), 2638.
Current quests in nucleosynthesis: present and future neutron-induced reaction measurements
Praena J., Pignatari M., et al. (2014), Current quests in nucleosynthesis: present and future neutron-induced reaction measurements, in EPJ Web of Conferences, 66, 66.
Experimental neutron capture data of 58Ni from the CERN n_TOF facility
Zureg P., et al.... (2014), Experimental neutron capture data of 58Ni from the CERN n_TOF facility, in Physical Review C, 89(2), 014605.
Impact of the uncertainty in alpha-captures on 22Ne on the weak s-process in massive stars
Nishimura N., Hirschi R., Pignatari M., et al. (2014), Impact of the uncertainty in alpha-captures on 22Ne on the weak s-process in massive stars, in AIP Conference Proceedings.
MESA and NuGrid simulations of classical novae: CO and ONe nova nucleosynthesis
Denissenkov P., Truran J., Pignatari M., et al. (2014), MESA and NuGrid simulations of classical novae: CO and ONe nova nucleosynthesis, in Monthly Notices of the Royal Astronomical Society, 442(3), 2058.
Ni62(n,gamma) and Ni63(n,gamma) cross sections measured at the n_TOF facility at CERN
Lederer C., et al... (2014), Ni62(n,gamma) and Ni63(n,gamma) cross sections measured at the n_TOF facility at CERN, in Physical Review C, 89(2), 025810.
Evidence for Radiogenic Sulfur-32 in Type AB Presolar Silicon Carbide Grains?
Fujiya Wataru, Hoppe P., Zinner E., Pignatari M., Herwig F. (2013), Evidence for Radiogenic Sulfur-32 in Type AB Presolar Silicon Carbide Grains?, in ApJ Letters, 776(2), 6.
Relics of Ancient Post-AGB Stars in a Primitive Meteorite
Jadhav M., Pignatari M., Herwig F., Zinner E., Gallino R., Huss G. (2013), Relics of Ancient Post-AGB Stars in a Primitive Meteorite, in ApJ Letters, 777(2), 7.
High-resolution abundance analysis of red giants in the globular cluster NGC 6522
Barbuy B., Chiappini C., Cantelli E., Depagne E., Pignatari M., et al., High-resolution abundance analysis of red giants in the globular cluster NGC 6522, in Astronomy & Astrophysics.

Collaboration

Group / person Country
Types of collaboration
Louisiana State Universtiy United States of America (North America)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
Arizona State University United States of America (North America)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
- Research Infrastructure
University of Monash Australia (Oceania)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
Universtaet Frankfurt/GSI Germany (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
Notre Dame University United States of America (North America)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
SUNY Stony Brook United States of America (North America)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
Observatory of Torino, INAF Italy (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
TRIUMF Canada (North America)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
McMaster University Canada (North America)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
Australian National University Australia (Oceania)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
U Chicago/Argonne United States of America (North America)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
University of Chicago United States of America (North America)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
Los Alamos National Laboratory United States of America (North America)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
Oak Ridge National Laboratory United States of America (North America)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
The University of Alabama United States of America (North America)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
University of Victoria Canada (North America)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
- Research Infrastructure
Keele University Great Britain and Northern Ireland (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Publication

Scientific events

Active participation

Title Type of contribution Title of article or contribution Date Place Persons involved
Fifteenth International Symposium on Capture Gamma-Ray Spectroscopy and Related Topics (CGS15) Talk given at a conference Impact of neutron capture reactions on s-process nucleosynthesis 25.08.2014 Dresden, Germany Pignatari Marco;
Nucleosynthesis in Asymptotic Giant Branch Stars, 568. WE Heraeus-Seminar Talk given at a conference AGB Stars and s process: a Laboratory for Nuclear Astrophysics 14.07.2014 Bad Honnef, Germany Pignatari Marco;
XIII Nuclei in the Cosmos Talk given at a conference Carbon-rich dust from supernovae: the rst connection with galactical chemical evolution 07.07.2014 Debrecen, Hungary Pignatari Marco;
17th Workshop on Nuclear Astrophysics Talk given at a conference Abundance signatures in presolar grains from core-collapse supernovae 07.04.2014 Ringberg, Germany Pignatari Marco;
The 11th Russbach School on Nuclear Astrophysics Talk given at a conference The intermediate neutron-capture process in stars, and its abundance signatures in presolar grains 09.03.2014 Russbach, Austria Pignatari Marco;
Seminar Individual talk The p process in massive stars 04.03.2014 Monash University, Melbourne, Australia Pignatari Marco;
RAS meeting, "Nucleosynthesis-Origins and Impacts" Talk given at a conference NuGrid Simulations and Explosive Events 14.02.2014 London, Great Britain and Northern Ireland Pignatari Marco;
Seminar Individual talk The intermediate neutron capture process in stars, and its abundance signature in presolar grains 05.02.2014 Mainz, Germany Pignatari Marco;
Athena Workshop Talk given at a conference The astrophysical aspects of neutron-capture nucleosynthesis, 27.01.2014 Brussel, Belgium Pignatari Marco;


Associated projects

Number Title Start Funding scheme
126428 A new comprehensive analysis of nucleosynthesis in stars: a bridge between nuclear astrophysics, stellar models and observations 01.09.2010 Ambizione
132816 Astrophysical Processes, their Simulation and Related Nuclear Physics Issues 01.10.2010 Project funding (Div. I-III)

Abstract

In the Solar System only less than 2% of the nuclear species are heavier than H and He. Those abundances are the result of the chemical enrichment of the Galaxy from many generations of stars. Besides the solar abundance distribution, information about stellar evolution and nucleosynthesis are obtained from stellar spectroscopic observations of different types of stars, in our Galaxy or more far away in extragalactic systems. Complementary information is hidden in tiny dust of presolar origin found in primitive meteorites (e.g., nano-diamonds, silicon carbides, graphites). Such grains were produced in stars before the formation of the Solar System, and were trapped into meteorites during their formation. They carry the isotopic signature of the nucleosynthesis processes in their respective parent star, and enable detailed laboratory abundance determinations. The stars that made this dust cannot be seen anymore, but it is still possible to "touch" them. In the cross disciplinary context of nuclear astrophysics, this project aims to shade new light into many open questions, addressing in first instance the fundamental question of how elements form in our galaxy and in the universe. The direction of research is twofold. First, a new interpretation of the abundances measured in presolar dust from massive stars is provided. We demonstrate that they are not made from extensive mixing of different layers of supernovae as it was assumed until now, but instead they only condensed from the external carbon-rich stellar layers of the supernova explosion. Thanks to this project, presolar grains can be correctly used as a constraint on massive star supernovae. Second, also thanks to the AMBIZIONE support since 2010, we made a fundamental advance in the knowledge of mixing properties of low-mass and intermediate-mass stars in their later evolutionary stages, studying the impact of Kelvin-Helmholtz instabilities and gravity waves on their evolution and on the production of the elements.
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