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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.

The diverse origins of neutron-capture elements in the metal-poor star HD 94028 : possible detection of products of i-process nucleosynthesis (2016)
Journal Article
Roederer, I. U., Karakas, A. I., Pignatari, M., & Herwig, F. (2016). The diverse origins of neutron-capture elements in the metal-poor star HD 94028 : possible detection of products of i-process nucleosynthesis. The Astrophysical journal, 821(1), Article ARTN 37. https://doi.org/10.3847/0004-637X/821/1/37

We present a detailed analysis of the composition and nucleosynthetic origins of the heavy elements in the metal-poor ([Fe/H] = −1.62 ± 0.09) star HD 94028. Previous studies revealed that this star is mildly enhanced in elements produced by the slow... Read More about The diverse origins of neutron-capture elements in the metal-poor star HD 94028 : possible detection of products of i-process nucleosynthesis.

The production of proton-rich isotopes beyond iron: The γ-process in stars (2016)
Journal Article
Pignatari, M., Göbel, K., Reifarth, R., & Travaglio, C. (2016). The production of proton-rich isotopes beyond iron: The γ-process in stars. International Journal of Modern Physics E, 25(4), Article 1630003. https://doi.org/10.1142/S0218301316300034

© 2016 World Scientific Publishing Company. Beyond iron, a small fraction of the total abundances in the Solar System is made of proton-rich isotopes, the p-nuclei. The clear understanding of their production is a fundamental challenge for nuclear as... Read More about The production of proton-rich isotopes beyond iron: The γ-process in stars.

STELLAR ORIGINS OF EXTREMELY C-13- AND N-15-ENRICHED PRESOLAR SIC GRAINS: NOVAE OR SUPERNOVAE? (2016)
Journal Article
Liu, N., Nittler, L. R., Alexander, C. M. O., Wang, J., Pignatari, M., José, J., & Nguyen, A. (2016). STELLAR ORIGINS OF EXTREMELY C-13- AND N-15-ENRICHED PRESOLAR SIC GRAINS: NOVAE OR SUPERNOVAE?. The Astrophysical journal, 820(2), 1-14. https://doi.org/10.3847/0004-637X/820/2/140

Extreme excesses of 13C (12C/13C < 10) and 15N (14N/15N < 20) in rare presolar SiC grains have been considered diagnostic of an origin in classical novae, though an origin in core collapse supernovae (CCSNe) has also been proposed. We report C, N, an... Read More about STELLAR ORIGINS OF EXTREMELY C-13- AND N-15-ENRICHED PRESOLAR SIC GRAINS: NOVAE OR SUPERNOVAE?.

First direct measurement of 12C (12C,n) 23Mg at stellar energies (2016)
Journal Article
Tang, X., Bucher, B., Fang, X., Heger, A., Almaraz-Calderon, S., Alongi, A., Ayangeakaa, A., Beard, M., Best, A., Browne, J., Cahillane, C., Couder, M., DeBoer, R., Kontos, A., Lamm, L., Li, Y., Long, A., Lu, W., Lyons, S., Notani, M., …Woosley, S. (2016). First direct measurement of 12C (12C,n) 23Mg at stellar energies. EPJ Web of Conferences, 109, 04009. https://doi.org/10.1051/epjconf/201610904009

© 2016 Owned by the authors, published by EDP Sciences. Neutrons produced by the carbon fusion reaction12C(12C,n)23Mg play an important role in stellar nucleosynthesis. Past studies have shown large discrepancies between experimental data and theory,... Read More about First direct measurement of 12C (12C,n) 23Mg at stellar energies.

Iron-group abundances in the metal-poor main-sequence turnoff star HD 84937 (2016)
Journal Article
Sneden, C., Cowan, J. J., Kobayashi, C., Pignatari, M., Lawler, J. E., Den Hartog, E. A., & Wood, M. P. (2016). Iron-group abundances in the metal-poor main-sequence turnoff star HD 84937. The Astrophysical journal, 817(1), 53. https://doi.org/10.3847/0004-637x/817/1/53

We have derived new, very accurate abundances of the Fe-group elements Sc through Zn (Z = 21−30) in the bright main-sequence turnoff star HD 84937 based on high-resolution spectra covering the visible and ultraviolet spectral regions. New or recent l... Read More about Iron-group abundances in the metal-poor main-sequence turnoff star HD 84937.

Origin of the p-process radionuclides ⁹²Nb and ¹⁴⁶Sm in the early solar system and inferences on the birth of the Sun (2016)
Journal Article
Lugaro, M., Pignatari, M., Ott, U., Zuber, K., Travaglio, C., Gyürky, G., & Fülöp, Z. (2016). Origin of the p-process radionuclides ⁹²Nb and ¹⁴⁶Sm in the early solar system and inferences on the birth of the Sun. Proceedings of the National Academy of Sciences of the United States of America, 113(4), 907-912. https://doi.org/10.1073/pnas.1519344113

The abundances of ⁹²Nb and ¹⁴⁶Sm in the early solar system are determined from meteoritic analysis, and their stellar production is attributed to the p process. We investigate if their origin from thermonuclear supernovae deriving from the explosion... Read More about Origin of the p-process radionuclides ⁹²Nb and ¹⁴⁶Sm in the early solar system and inferences on the birth of the Sun.

Experiments with neutron beams for the astrophysical s process (2016)
Journal Article
Lederer, C., Altstadt, S., Andrzejewski, J., Audouin, L., Barbagallo, M., Bécares, V., Bečvář, F., Belloni, F., Berthoumieux, E., Billowes, J., Boccone, V., Bosnar, D., Brugger, M., Calviani, M., Calviño, F., Cano-Ott, D., Carrapiço, C., Cerutti, F., Chiaveri, E., Chin, M., …Žugec, P. (2016). Experiments with neutron beams for the astrophysical s process. Journal of Physics: Conference Series, 665(1), 012020. https://doi.org/10.1088/1742-6596/665/1/012020

© Published under licence by IOP Publishing Ltd. Neutron capture cross sections are the key nuclear physics input to study the slow neutron capture process, which is responsible for forming about half of the elemental abundances above Fe. Stellar neu... Read More about Experiments with neutron beams for the astrophysical s process.

Sensitivity study for s process nucleosynthesis in AGB stars (2016)
Journal Article
Koloczek, A., Thomas, B., Glorius, J., Plag, R., Pignatari, M., Reifarth, R., Ritter, C., Schmidt, S., & Sonnabend, K. (2016). Sensitivity study for s process nucleosynthesis in AGB stars. Atomic Data and Nuclear Data Tables, 108(March), 1-14. https://doi.org/10.1016/j.adt.2015.12.001

In this paper we present a large-scale sensitivity study of reaction rates in the main component of the s process. The aim of this study is to identify all rates, which have a global effect on the s process abundance distribution and the three most i... Read More about Sensitivity study for s process nucleosynthesis in AGB stars.