Evolution of dwarf galaxies hosting GW150914-like events

• Main Authors: Marassi, S, Graziani, L, Ginolfi, M, Schneider, R, Mapelli, M, Spera, M, Alparone, M
• Format: Journal Article
• Language: English
• Published: 16-01-2019
• Subjects: Physics - Astrophysics of Galaxies; Physics - Cosmology and Nongalactic Astrophysics
• DOI: 10.48550/arxiv.1901.04494

Here we present a detailed analysis of the properties and evolution of
different dwarf galaxies, candidate to host the coalescence of black hole
binary systems (BHB) generating GW150914-like events. By adopting a novel
theoretical framework coupling the binary population synthesis code
\texttt{SeBa} with the Galaxy formation model \texttt{GAMESH}, we can
investigate the detailed evolution of these objects in a well resolved
cosmological volume of 4~cMpc, having a Milky Way-like (MW) galaxy forming at
its center. We identify three classes of interesting candidate galaxies: MW
progenitors, dwarf satellites and dwarf galaxies evolving in isolation. We find
that: (i) despite differences in individual histories and specific environments
the candidates reduce to only nine representative galaxies; (ii) among them,
$\sim44\%$ merges into the MW halo progenitors by the redshift of the expected
signal, while the remaining dwarfs are found as isolated or as satellites of
the MW and their evolution is strongly shaped by both peculiar dynamical
history and environmental feedback; (iii) a stringent condition for the
environments where GW150914-like binaries can form comes from a combination of
the accretion history of their DM halos and the radiative feedback in the high
redshift universe; (iv) by comparing with the observed catalogues from DGS and
ALLSMOG surveys we find two observed dwarfs respecting the properties predicted
by our model. We finally note how the present analysis opens the possibility to
build future strategies for host galaxy identification.