Neutron-capture elements in dwarf galaxies II: Challenges for the s- and i-processes at low metallicity

Autor: Arthur Choplin, A. Skuladottir, Camilla Juul Hansen, Stefania Salvadori, Simon Campbell, Melanie Hampel

The slow ($s$) and intermediate ($i$) neutron ($n$) capture processes occur both in asymptotic giant branch (AGB) stars, and in massive stars. To study the build-up of the $s$- and $i$-products at low metallicity, we investigate the abundances of Y,

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::deaa85c882c1370034b4375db126a078
http://arxiv.org/abs/1912.06671

Unusual neutron-capture nucleosynthesis in a carbon-rich Galactic bulge star

Autor: Richard J. Stancliffe, Melanie Hampel, Andreas Koch, Almudena Arcones, Camilla Juul Hansen, Moritz Reichert, Amanda I. Karakas

Publikováno v: Astronomy and Astrophysics
Koch, A, Reichert, M, Hansen, C J, Hampel, M, Stancliffe, R J, Karakas, A & Arcones, A 2019, ' Unusual neutron-capture nucleosynthesis in a carbon-rich Galactic bulge star ', Astronomy & Astrophysics, vol. 622, A159 . https://doi.org/10.1051/0004-6361/201834241
Astronomy and astrophysics 622, A159-(2019). doi:10.1051/0004-6361/201834241
Astronomy & Astrophysics

Metal-poor stars in the Galactic halo often show strong enhancements in carbon and/or neutron-capture elements. However, the Galactic bulge is notable for its paucity of carbon-enhanced metal-poor (CEMP) and/or CH-stars, with only two such objects kn

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::a00a83c84cc2ca992901dc4087db3b8f

Learning about the Intermediate Neutron-capture Process from Lead Abundances

Autor: Amanda I. Karakas, Melanie Hampel, Bradley S. Meyer, Maria Lugaro, Richard J. Stancliffe

Publikováno v: The Astrophysical Journal. 887:11

Lead (Pb) is predominantly produced by the slow neutron-capture process (s process) in asymptotic giant branch (AGB) stars. In contrast to significantly enhanced Pb abundances predicted by low-mass, low-metallicity AGB-models, observations of Magella

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::511dbd19407dc2bd7a628d61807fce5b
https://doi.org/10.3847/1538-4357/ab4fe8

R Coronae Borealis Stars are Viable Factories of Pre-solar Grains

Autor: Melanie Hampel, Amanda I. Karakas, Ashley J. Ruiter

We present a new theoretical estimate for the birthrate of R Coronae Borealis (RCB) stars that is in agreement with recent observational data. We find the current Galactic birthrate of RCB stars to be $\approx$ 25% of the Galactic rate of Type Ia sup

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::86bb0bf36541489767d1aadf73b8732d
http://arxiv.org/abs/1507.06367

Origin of Large Meteoritic SiC Stardust Grains in Metal-rich AGB Stars

Autor: Blanka Világos, Melanie Hampel, G. Tagliente, Valentina D'Orazi, F. Dell'Agli, U. Battino, Paolo Ventura, Josef Hron, Gyula M. Szabó, Amanda I. Karakas, Reto Trappitsch, Claudio B. Pereira, Larry R. Nittler, Maria Schönbächler, Marco Pignatari, Mattias Ek, B. Cseh, Maria Lugaro, A. Tattersall

Publikováno v: The Astrophysical Journal

Stardust grains that originated in ancient stars and supernovae are recovered from meteorites and carry the detailed composition of their astronomical sites of origin. We present evidence that the majority of large ($\mu$m-sized) meteoritic silicon c

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::e2eacb43cd7b238cc7b2e134bcf21b86