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s-process production in rotating massive stars at solar and low metallicities (2015)
Journal Article
Frischknecht, U., Hirschi, R., Pignatari, M., Maeder, A., Meynet, G., Chiappini, C., …Ekström, S. (2016). s-process production in rotating massive stars at solar and low metallicities. Monthly notices of the Royal Astronomical Society, 456(2), 1803-1825. https://doi.org/10.1093/mnras/stv2723

Rotation was shown to have a strong impact on the structure and light element nucleosynthesis in massive stars. In particular, models including rotation can reproduce the primary nitrogen observed in halo extremely metal poor (EMP) stars. Additional... Read More about s-process production in rotating massive stars at solar and low metallicities.

H ingestion into He-burning convection zones in super-AGB stellar models as a potential site for intermediate neutron-density nucleosynthesis (2015)
Journal Article
Jones, S., Ritter, C., Herwig, F., Fryer, C., Pignatari, M., Bertolli, M. G., & Paxton, B. (2016). H ingestion into He-burning convection zones in super-AGB stellar models as a potential site for intermediate neutron-density nucleosynthesis. Monthly notices of the Royal Astronomical Society, 455(4), 3848-3863. https://doi.org/10.1093/mnras/stv2488

We investigate the evolution of super-AGB (SAGB) thermal pulse (TP) stars for a range of metallicities (Z) and explore the effect of convective boundary mixing (CBM). With decreasing metallicity and evolution along the TP phase, the He-shell flash an... Read More about H ingestion into He-burning convection zones in super-AGB stellar models as a potential site for intermediate neutron-density nucleosynthesis.

Mn abundances in the stars of the Galactic disc with metallicities -1.0 < [Fe/H] < 0.3 (2015)
Journal Article
Mishenina, T., Gorbaneva, T. I., Pignatari, M., Thielemann, F., & Korotin, S. (2015). Mn abundances in the stars of the Galactic disc with metallicities -1.0 < [Fe/H] < 0.3. Monthly notices of the Royal Astronomical Society, 454(2), 1585-1594. https://doi.org/10.1093/mnras/stv2038

In this work we present and discuss the observations of the Mn abundances for 247 FGK dwarfs, located in the Galactic disc with metallicity -1 < [Fe/H]< +0.3. The observed stars belong to the substructures of the Galaxy thick and thin discs, and to t... Read More about Mn abundances in the stars of the Galactic disc with metallicities -1.0 < [Fe/H] < 0.3.

Carbon-rich presolar grains from massive stars : subsolar ¹²C/¹³C and ¹⁴N/¹⁵N ratios and the mystery of ¹⁵N (2015)
Journal Article
Pignatari, M., Zinner, E., Hoppe, P., J. Jordan, C., K. Gibson, B., Trappitsch, R., …X. Timmes, F. (2015). Carbon-rich presolar grains from massive stars : subsolar ¹²C/¹³C and ¹⁴N/¹⁵N ratios and the mystery of ¹⁵N. Astrophysical journal. Letters, 808(2), L43. https://doi.org/10.1088/2041-8205/808/2/L43

Carbon-rich grains with isotopic anomalies compared to the Sun are found in primitive meteorites. They were made by stars, and carry the original stellar nucleosynthesis signature. Silicon carbide grains of Type X and C and low-density (LD) graphites... Read More about Carbon-rich presolar grains from massive stars : subsolar ¹²C/¹³C and ¹⁴N/¹⁵N ratios and the mystery of ¹⁵N.

Galactic evolution of rapid neutron capture process abundances: The inhomogeneous approach (2015)
Journal Article
Wehmeyer, B., Pignatari, M., & Thielemann, F. (2015). Galactic evolution of rapid neutron capture process abundances: The inhomogeneous approach. Monthly notices of the Royal Astronomical Society, 452(2), 1970-1981. https://doi.org/10.1093/mnras/stv1352

For the origin of heavy r-process elements, different sources have been proposed, e.g., core-collapse supernovae or neutron star mergers. Old metal-poor stars carry the signature of the astrophysical source(s). Among the elements dominantly made by t... Read More about Galactic evolution of rapid neutron capture process abundances: The inhomogeneous approach.

The first direct measurement of ¹²C (¹²C,n) ²³Mg at stellar energies (2015)
Journal Article
Bucher, B., Tang, X. D., Fang, X., Heger, A., Alamaraz-Calderon, S., Alongi, A., …Woosley, S. E. (2015). The first direct measurement of ¹²C (¹²C,n) ²³Mg at stellar energies. Physical review letters, 114(25), 251102. https://doi.org/10.1103/PhysRevLett.114.251102

Neutrons produced by the carbon fusion reaction ¹²C(¹²C,n)²³Mg play an important role in stellar nucleosynthesis. However, past studies have shown large discrepancies between experimental data and theory, leading to an uncertain cross section extrapo... Read More about The first direct measurement of ¹²C (¹²C,n) ²³Mg at stellar energies.

Nucleosynthesis simulations for the production of the p-nuclei 92Mo and 94Mo in a Supernova type II model (2015)
Journal Article
Göbel, K., Glorius, J., Koloczek, A., Pignatari, M., Reifarth, R., Schach, R., & Sonnabend, K. (2015). Nucleosynthesis simulations for the production of the p-nuclei 92Mo and 94Mo in a Supernova type II model. EPJ Web of Conferences, 93, 03006. https://doi.org/10.1051/epjconf/20159303006

We present a nucleosynthesis sensitivity study for the γ-process in a Supernova type II model within the NuGrid research platform. The simulations aimed at identifying the relevant local production and destruction rates for the p-nuclei of molybdenum... Read More about Nucleosynthesis simulations for the production of the p-nuclei 92Mo and 94Mo in a Supernova type II model.

Constraining the 12C+12C fusion cross section for astrophysics (2015)
Journal Article
Bucher, B., Fang, X., Tang, X., Tan, W., Almaraz-Calderon, S., Alongi, A., …Wiescher, M. (2015). Constraining the 12C+12C fusion cross section for astrophysics. EPJ Web of Conferences, 93, 03009. https://doi.org/10.1051/epjconf/20159303009

The 12 C+ 12 C reaction is one of the single most important nuclear reactions in astrophysics. It strongly influences late evolution of massive stars as well as the dynamics of type Ia supernovae and x-ray superbursts. An accurate estimation of the c... Read More about Constraining the 12C+12C fusion cross section for astrophysics.

Experimental neutron capture data of 58Ni from the CERN n_TOF facility (2015)
Journal Article
Žugec, P., Barbagallo, M., Colonna, N., Bosnar, D., Altstadt, S., Andrzejewski, J., …Wright, T. (2015). Experimental neutron capture data of 58Ni from the CERN n_TOF facility. EPJ Web of Conferences, 93, 02009. https://doi.org/10.1051/epjconf/20159302009

The neutron capture cross section of 58 Ni was measured at the neutron time of flight facility n-TOF at CERN, from 27 meV to 400 keV neutron energy. Special care has been taken to identify all the possible sources of background, with the so-called ne... Read More about Experimental neutron capture data of 58Ni from the CERN n_TOF facility.

Sulfur isotopic compositions of submicrometer SiC grains from the Murchison meteorite (2015)
Journal Article
Xu, Y., Zinner, E., Gallino, R., Heger, A., Pignatari, M., & Lin, Y. (2015). Sulfur isotopic compositions of submicrometer SiC grains from the Murchison meteorite. The Astrophysical journal, 799(2), 156. https://doi.org/10.1088/0004-637x/799/2/156

We report C, Si, N, S, Mg-Al, and Ca-Ti isotopic compositions of presolar silicon carbide (SiC) grains from the SiC-rich KJE size fraction (0.5-0.8 μm) of the Murchison meteorite. One thousand one hundred thirteen SiC grains were identified based on... Read More about Sulfur isotopic compositions of submicrometer SiC grains from the Murchison meteorite.

Code dependencies of pre-supernova evolution and nucleosynthesis in massive stars: Evolution to the end of core helium burning (2015)
Journal Article
Jones, S., Hirschi, R., Pignatari, M., Heger, A., Georgy, C., Nishimura, N., …Herwig, F. (2015). Code dependencies of pre-supernova evolution and nucleosynthesis in massive stars: Evolution to the end of core helium burning. Monthly notices of the Royal Astronomical Society, 447(4), 3115-3129. https://doi.org/10.1093/mnras/stu2657

Massive stars are key sources of radiative, kinetic and chemical feedback in the Universe. Grids of massive star models computed by different groups each using their own codes, input physics choices and numerical approximations, however, lead to inco... Read More about Code dependencies of pre-supernova evolution and nucleosynthesis in massive stars: Evolution to the end of core helium burning.