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Precise measurement of the thermal and stellar Fe 54 (n,γ) Fe 55 cross sections via accelerator mass spectrometry (2017)
Journal Article
Wallner, A., Buczak, K., Belgya, T., Bichler, M., Coquard, L., Dillmann, I., Golser, R., Käppeler, F., Karakas, A., Kutschera, W., Lederer, C., Mengoni, A., Priller, A., Reifarth, R., Steier, P., Szentmiklosi, L., Kaeppeler, F., & Pignatari, M. (2017). Precise measurement of the thermal and stellar Fe 54 (n,γ) Fe 55 cross sections via accelerator mass spectrometry. Physical Review C, 96(2), Article ARTN 025808. https://doi.org/10.1103/PhysRevC.96.025808

© 2017 authors. Published by the American Physical Society. Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the a... Read More about Precise measurement of the thermal and stellar Fe 54 (n,γ) Fe 55 cross sections via accelerator mass spectrometry.

Convective–reactive nucleosynthesis of K, Sc, Cl and p-process isotopes in O–C shell mergers (2017)
Journal Article
Ritter, C., Andrassy, R., Côté, B., Herwig, F., Woodward, P. R., Pignatari, M., & Jones, S. (2018). Convective–reactive nucleosynthesis of K, Sc, Cl and p-process isotopes in O–C shell mergers. Monthly notices of the Royal Astronomical Society. Letters, 474(1), L1-L6. https://doi.org/10.1093/mnrasl/slx126

© 2017 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society. We address the deficiency of odd-Z elements P, Cl, K and Sc in Galactic chemical evolution models through an investigation of the nucleosynthesis... Read More about Convective–reactive nucleosynthesis of K, Sc, Cl and p-process isotopes in O–C shell mergers.

The neutron capture process in the He shell in core-collapse supernovae: Presolar silicon carbide grains as a diagnostic tool for nuclear astrophysics (2017)
Journal Article
Pignatari, M., Hoppe, P., Trappitsch, R., Fryer, C., Timmes, F., Herwig, F., & Hirschi, R. (2018). The neutron capture process in the He shell in core-collapse supernovae: Presolar silicon carbide grains as a diagnostic tool for nuclear astrophysics. Geochimica et cosmochimica acta, 221, 37-46. https://doi.org/10.1016/j.gca.2017.06.005

Carbon-rich presolar grains are found in primitive meteorites, with isotopic measurements to date suggesting a core-collapse supernovae origin site for some of them. This holds for about 1-2 % of presolar silicon carbide (SiC) grains, so-called Type... Read More about The neutron capture process in the He shell in core-collapse supernovae: Presolar silicon carbide grains as a diagnostic tool for nuclear astrophysics.

Stellar origin of 15N-rich presolar SiC grains of type AB: Supernovae with explosive hydrogen burning (2017)
Journal Article
Liu, N., Nittler, L. R., Pignatari, M., Alexander, C. M. O., & Wang, J. (2017). Stellar origin of 15N-rich presolar SiC grains of type AB: Supernovae with explosive hydrogen burning. The Astrophysical journal, 842(1), L1. https://doi.org/10.3847/2041-8213/aa74e5

© 2017. The American Astronomical Society. All rights reserved. We report C, N, and Si isotopic data for 59 highly 13 C-enriched presolar submicron-to micron-sized SiC grains from the Murchison meteorite, including eight putative nova grains (PNGs)... Read More about Stellar origin of 15N-rich presolar SiC grains of type AB: Supernovae with explosive hydrogen burning.

Iron and nickel isotope compositions of presolar silicon carbide grains from supernovae (2017)
Journal Article
Kodolányi, J., Stephan, T., Trappitsch, R., Hoppe, P., Pignatari, M., Davis, A. M., & Pellin, M. J. (2018). Iron and nickel isotope compositions of presolar silicon carbide grains from supernovae. Geochimica et cosmochimica acta, 221, 127-144. https://doi.org/10.1016/j.gca.2017.05.029

© 2017 Elsevier Ltd. We report the carbon, silicon, iron, and nickel isotope compositions of twenty-five presolar SiC grains of mostly supernova (SN) origin. The iron and nickel isotope compositions were measured with the new Chicago Instrument for L... Read More about Iron and nickel isotope compositions of presolar silicon carbide grains from supernovae.

Observing the metal-poor solar neighbourhood: A comparison of galactic chemical evolution predictions (2017)
Journal Article
Mishenina, T., Pignatari, M., Côté, B., Thielemann, F.-K., Soubiran, C., Basak, N., Gorbaneva, T., Korotin, S. A., Kovtyukh, V. V., Wehmeyer, B., Bisterzo, S., Travaglio, C., Gibson, B. K., Jordan, C., Paul, A., Ritter, C., & Herwig, F. (2017). Observing the metal-poor solar neighbourhood: A comparison of galactic chemical evolution predictions. Monthly notices of the Royal Astronomical Society. Letters, 469(4), 4378-4399. https://doi.org/10.1093/mnras/stx1145

© 2017 The Authors. Atmospheric parameters and chemical compositions for 10 stars with metallicities in the region of -2.2 < [Fe/H] < -0.6 were precisely determined using high-resolution, high signal-tonoise, spectra. For each star, the abundance... Read More about Observing the metal-poor solar neighbourhood: A comparison of galactic chemical evolution predictions.

A chemical signature from fast-rotating low-metallicity massive stars: ROA 276 in ω Centauri (2017)
Journal Article
Yong, D., Norris, J. E., Da Costa, G. S., Stanford, L. M., Karakas, A. I., Shingles, L. J., Hirschi, R., & Pignatari, M. (2017). A chemical signature from fast-rotating low-metallicity massive stars: ROA 276 in ω Centauri. The Astrophysical journal, 837(2), 176. https://doi.org/10.3847/1538-4357/aa6250

© 2017. The American Astronomical Society. All rights reserved. We present a chemical abundance analysis of a metal-poor star, ROA 276, in the stellar system ω Centauri. We confirm that this star has an unusually high [Sr/Ba] abundance ratio. Additio... Read More about A chemical signature from fast-rotating low-metallicity massive stars: ROA 276 in ω Centauri.

Neutron spectroscopy of 26 Mg states: Constraining the stellar neutron source 22 Ne( α , n ) 25 Mg (2017)
Journal Article
Kivel, N., Karadimos, D., Käppeler, F., Kadi, Y., Krtička, M., Kopecky, S., Kokkoris, M., Koehler, P., Leal-Cidoncha, E., Langer, C., Lampoudis, C., Kroll, J., Losito, R., Lo Meo, S., Leeb, H., Lederer, C., Mastromarco, M., Martínez, T., Marganiec, J., Manousos, A., …Schillebeeckx, P. (2017). Neutron spectroscopy of 26 Mg states: Constraining the stellar neutron source 22 Ne( α , n ) 25 Mg. Physics letters. B, 768, 1-6. https://doi.org/10.1016/j.physletb.2017.02.025

This work reports on accurate, high-resolution measurements of the 25 Mg(n,γ) 26 Mg and 25 Mg(n,tot) cross sections in the neutron energy range from thermal to about 300 keV, leading to a significantly improved 25 Mg(n,γ) 26 Mg parametrization. The r... Read More about Neutron spectroscopy of 26 Mg states: Constraining the stellar neutron source 22 Ne( α , n ) 25 Mg.

NanoSIMS isotope studies of rare types of presolar silicon carbide grains from the Murchison meteorite: Implications for supernova models and the role of 14C (2017)
Journal Article
Hoppe, P., Pignatari, M., Kodolányi, J., Gröner, E., & Amari, S. (2018). NanoSIMS isotope studies of rare types of presolar silicon carbide grains from the Murchison meteorite: Implications for supernova models and the role of 14C. Geochimica et cosmochimica acta, 221, 182-199. https://doi.org/10.1016/j.gca.2017.01.051

© 2017 Elsevier Ltd. We have conducted a NanoSIMS ion imaging survey of about 1800 presolar silicon carbide (SiC) grains from the Murchison meteorite. A total of 21 supernova (SN) X grains, two SN C grains, and two putative nova grains were identifie... Read More about NanoSIMS isotope studies of rare types of presolar silicon carbide grains from the Murchison meteorite: Implications for supernova models and the role of 14C.

Stellar (n,γ) cross sections of ²³Na (2017)
Journal Article
Uberseder, E., Heil, M., Käppeler, F., Lederer, C., Mengoni, A., Bisterzo, S., Pignatari, M., & Wiescher, M. (2017). Stellar (n,γ) cross sections of ²³Na. Physical Review C, 95(2), 025803. https://doi.org/10.1103/PhysRevC.95.025803

The cross section of the ²³Na(n,γ)²⁴Na reaction has been measured via the activation method at the Karlsruhe 3.7 MV Van de Graaff accelerator. NaCl samples were exposed to quasistellar neutron spectra at kT = 5.1 and 25 keV produced via the ¹⁸O(p,n)¹... Read More about Stellar (n,γ) cross sections of ²³Na.

i-process Nucleosynthesis and Mass Retention Efficiency in He-shell Flash Evolution of Rapidly Accreting White Dwarfs (2017)
Journal Article
Denissenkov, P. A., Herwig, F., Battino, U., Ritter, C., Pignatari, M., Jones, S., & Paxton, B. (2017). i-process Nucleosynthesis and Mass Retention Efficiency in He-shell Flash Evolution of Rapidly Accreting White Dwarfs. Astrophysical journal. Letters, 834(2), L10. https://doi.org/10.3847/2041-8213/834/2/l10

© 2017. The American Astronomical Society. All rights reserved. Based on stellar evolution simulations, we demonstrate that rapidly accreting white dwarfs (WDs) in close binary systems are an astrophysical site for the intermediate neutron-capture pr... Read More about i-process Nucleosynthesis and Mass Retention Efficiency in He-shell Flash Evolution of Rapidly Accreting White Dwarfs.

Stellar yields and abundances: new directions from planetary nebulae (2016)
Journal Article
Lugaro, M., Karakas, A. I., Pignatari, M., & Doherty, C. L. (2016). Stellar yields and abundances: new directions from planetary nebulae. IAU symposium and colloquium proceedings series / International Astronomical Union. Symposium, 12(S323), 86-94. https://doi.org/10.1017/s1743921317001247

Copyright © International Astronomical Union 2017. Planetary nebulae retain the signature of the nucleosynthesis and mixing events that occurred during the previous AGB phase. Observational signatures complement observations of AGB and post-AGB stars... Read More about Stellar yields and abundances: new directions from planetary nebulae.

Looking for imprints of the first stellar generations in metal-poor bulge field stars (2016)
Journal Article
Chiappini, C., Freeman, K., Ness, M., Depagne, E., Cantelli, E., Hirschi, R., Frischknecht, U., Maeder, A., Pignatari, M., Barbuy, B., Cantelli, E. W. C., Chiappini, C., Depagne, É., Freeman, K., Frischknecht, U., Hirschi, R., Maeder, A., Meynet, G., Ness, M., & Siqueira-Mello, C. (2016). Looking for imprints of the first stellar generations in metal-poor bulge field stars. Astronomy and Astrophysics, 593, A79-1-A79-16. https://doi.org/10.1051/0004-6361/201628104

© 2016 ESO. Context. Efforts to look for signatures of the first stars have concentrated on metal-poor halo objects. However, the low end of the bulge metallicity distribution has been shown to host some of the oldest objects in the Milky Way and hen... Read More about Looking for imprints of the first stellar generations in metal-poor bulge field stars.

NuGrid stellar data set. 1. Stellar yields from H to Bi for stars with metallicities Z=0.02 and Z=0.01 (2016)
Journal Article
Pignatari, M., Herwig, F., Hirschi, R., Bennett, M., Rockefeller, G., Fryer, C., X. Timmes, F., Ritter, C., Heger, A., Jones, S., Battino, U., Dotter, A., Trappitsch, R., Diehl, S., Frischknecht, U., Hungerford, A., Magkotsios, G., Travaglio, C., & Young, P. (2016). NuGrid stellar data set. 1. Stellar yields from H to Bi for stars with metallicities Z=0.02 and Z=0.01. Astrophysical Journal Supplement, 225(2), Article ARTN 24. https://doi.org/10.3847/0067-0049/225/2/24

We provide a set of stellar evolution and nucleosynthesis calculations that applies established physics assumptions simultaneously to low- and intermediate-mass and massive star models. Our goal is to provide an internally consistent and comprehensiv... Read More about NuGrid stellar data set. 1. Stellar yields from H to Bi for stars with metallicities Z=0.02 and Z=0.01.

Re-evaluation of the ¹⁶O(n, γ)¹⁷O cross section at astrophysical energies and its role as a neutron poison in the s-process (2016)
Journal Article
Mohr, P., Heinz, C., Pignatari, M., Dillmann, I., Mengoni, A., & Käppeler, F. (2016). Re-evaluation of the ¹⁶O(n, γ)¹⁷O cross section at astrophysical energies and its role as a neutron poison in the s-process. The Astrophysical journal, 827(1), Article ARTN 29. https://doi.org/10.3847/0004-637X/827/1/29

The doubly magic nucleus ¹⁶O has a small neutron-capture cross section of just a few tens of microbarns in the astrophysical energy region. Despite this, ¹⁶O plays an important role as a neutron poison in the astrophysical slow neutron capture (s) pr... Read More about Re-evaluation of the ¹⁶O(n, γ)¹⁷O cross section at astrophysical energies and its role as a neutron poison in the s-process.

Application of a theory and simulation-based convective boundary mixing model for AGB star evolution and nucleosynthesis (2016)
Journal Article
Battino, U., Pignatari, M., Ritter, C., Herwig, F., Denisenkov, P., Den Hartogh, J. W., Trappitsch, R., Hirschi, R., Freytag, B., Thielemann, F., & Paxton, B. (2016). Application of a theory and simulation-based convective boundary mixing model for AGB star evolution and nucleosynthesis. The Astrophysical journal, 827(1), 30. https://doi.org/10.3847/0004-637X/827/1/30

The s-process nucleosynthesis in Asymptotic giant branch (AGB) stars depends on the modeling of convective boundaries. We present models and s-process simulations that adopt a treatment of convective boundaries based on the results of hydrodynamic si... Read More about Application of a theory and simulation-based convective boundary mixing model for AGB star evolution and nucleosynthesis.

Inhomogeneous chemical evolution of r-process elements (2016)
Presentation / Conference Contribution
Wehmeyer, B., Pignatari, M., & Thielemann, F.-K. Inhomogeneous chemical evolution of r-process elements. Presented at CETUP* 2015 – WORKSHOP ON DARK MATTER, NEUTRINO PHYSICS AND ASTROPHYSICS AND PPC 2015 – IXTH INTERNATIONAL CONFERENCE ON INTERCONNECTIONS BETWEEN PARTICLE PHYSICS AND COSMOLOGY, Deadwood, South Dakota, USA

We report the results of a galactic chemical evolution (GCE) study for r-process- and alpha elements. For this work, we used the inhomogeneous GCE model "ICE", which allows to keep track of the galactic abundances of elements produced by different as... Read More about Inhomogeneous chemical evolution of r-process elements.

Uncertainties in Galactic Chemical Evolution Models (2016)
Journal Article
Côté, B., Ritter, C., O’Shea, B. W., Herwig, F., Pignatari, M., Jones, S., & Fryer, C. L. (2016). Uncertainties in Galactic Chemical Evolution Models. The Astrophysical journal, 824(2), Article ARTN 82. https://doi.org/10.3847/0004-637X/824/2/82

We use a simple one-zone galactic chemical evolution model to quantify the uncertainties generated by the input parameters in numerical predictions for a galaxy with properties similar to those of the Milky Way. We compiled several studies from the l... Read More about Uncertainties in Galactic Chemical Evolution Models.

Probing astrophysically important states in the ²⁶Mg nucleus to study neutron sources for the s process (2016)
Journal Article
Talwar, R., Adachi, T., Berg, G. P. A., Bin, L., Bisterzo, S., Couder, M., deBoer, R. J., Fang, X., Fujita, H., Fujita, Y., Görres, J., Hatanaka, K., Itoh, T., Kadoya, T., Long, A., Miki, K., Patel, D., Pignatari, M., Shimbara, Y., Tamii, A., …Yosoi, M. (2016). Probing astrophysically important states in the ²⁶Mg nucleus to study neutron sources for the s process. Physical Review C, 93(5), https://doi.org/10.1103/physrevc.93.055803

Background: The ²²Ne(α,n) ²⁵Mg reaction is the dominant neutron source for the slow neutron capture process (s process) in massive stars, and contributes, together with C¹³(α,n)O¹⁶, to the production of neutrons for the s process in asymptotic giant... Read More about Probing astrophysically important states in the ²⁶Mg nucleus to study neutron sources for the s process.