Help Privacy Policy Disclaimer
  Advanced SearchBrowse




Journal Article

Retainment of r-process material in dwarf galaxies


Dvorkin,  Irina
Astrophysical and Cosmological Relativity, AEI-Golm, MPI for Gravitational Physics, Max Planck Society;

External Resource
No external resources are shared
Fulltext (public)

(Preprint), 521KB

Supplementary Material (public)
There is no public supplementary material available

Beniamini, P., Dvorkin, I., & Silk, J. (2018). Retainment of r-process material in dwarf galaxies. Monthly Notices of the Royal Astronomical Society, 478, 1994-2005. doi:10.1093/mnras/sty1035.

Cite as: http://hdl.handle.net/21.11116/0000-0001-98B2-A
The synthesis of $r$-process elements is known to involve extremely energetic explosions. At the same time, recent observations find significant $r$-process enrichment even in extremely small ultra-faint dwarf (UFD) galaxies. This raises the question of retainment of those elements within their hosts. We estimate the retainment fraction and find that it is large $\sim 0.9$, unless the $r$-process event is very energetic ($\gtrsim 10^{52}$erg) and / or the host has lost a large fraction of its gas prior to the event. We estimate the $r$-process mass per event and rate as implied by abundances in UFDs, taking into account imperfect retainment and different models of UFD evolution. The results are consistent with previous estimates \citep{Beniamini2016} and with the constraints from the recently detected macronova accompanying a neutron star merger (GW170817). We also estimate the distribution of abundances predicted by these models. We find that $\sim 0.07$ of UFDs should have $r$-process enrichment. The results are consistent with both the mean values and the fluctuations of [Eu/Fe] in galactic metal poor stars, supporting the possibility that UFDs are the main 'building blocks' of the galactic halo population.