Linking the brightest stellar streams with the accretion history of Milky Way-like galaxies. (arXiv:2105.06467v1 [astro-ph.GA])
<a href="http://arxiv.org/find/astro-ph/1/au:+Vera_Casanova_A/0/1/0/all/0/1">Alex Vera-Casanova</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Gomez_F/0/1/0/all/0/1">Facundo A. G&#xf3;mez</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Monachesi_A/0/1/0/all/0/1">Antonela Monachesi</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Gargiulo_I/0/1/0/all/0/1">Ignacio Gargiulo</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Pallero_D/0/1/0/all/0/1">Diego Pallero</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Grand_R/0/1/0/all/0/1">Robert J. J. Grand</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Marinacci_F/0/1/0/all/0/1">Federico Marinacci</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Pakmor_R/0/1/0/all/0/1">R&#xfc;diger Pakmor</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Simpson_C/0/1/0/all/0/1">Christine M. Simpson</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Frenk_C/0/1/0/all/0/1">Carlos S. Frenk</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Morales_G/0/1/0/all/0/1">Gustavo Morales</a>

According to the current galaxy formation paradigm, mergers and interactions
play an important role in shaping present-day galaxies. The remnants of this
merger activity can be used to constrain galaxy formation models. In this work
we use a sample of thirty hydrodynamical simulations of Milky Way-mass halos,
from the AURIGA project, to generate surface brightness maps and search for the
brightest stream in each halo as a function of varying limiting magnitude. We
find that none of the models shows signatures of stellar streams at
$mu_{r}^{lim} leq 25$ mag arcsec$^{-2}$. The stream detection increases
significantly between 27 and 28 mag arcsec$^{-2}$. Nevertheless, even at 30 mag
arcsec$^{-2}$, 13 percent of our models show no detectable streams. We study
the properties of the brightest streams progenitors (BSPs). We find that BSPs
are accreted within a broad range of infall times, from 1.6 to 10 Gyr ago, with
only 25 percent accreted within the last 5 Gyrs; thus most BSPs correspond to
relatively early accretion events. We also find that 37 percent of the BSPs
survive to the present day. The median infall times for surviving and disrupted
BSPs are 5.6 and 6.7 Gyr, respectively. We find a clear relation between infall
time and infall mass of the BSPs, such that more massive progenitors tend to be
accreted at later times. However, we find that the BSPs are not, in most cases,
the dominant contributor to the accreted stellar halo of each galaxy.

According to the current galaxy formation paradigm, mergers and interactions
play an important role in shaping present-day galaxies. The remnants of this
merger activity can be used to constrain galaxy formation models. In this work
we use a sample of thirty hydrodynamical simulations of Milky Way-mass halos,
from the AURIGA project, to generate surface brightness maps and search for the
brightest stream in each halo as a function of varying limiting magnitude. We
find that none of the models shows signatures of stellar streams at
$mu_{r}^{lim} leq 25$ mag arcsec$^{-2}$. The stream detection increases
significantly between 27 and 28 mag arcsec$^{-2}$. Nevertheless, even at 30 mag
arcsec$^{-2}$, 13 percent of our models show no detectable streams. We study
the properties of the brightest streams progenitors (BSPs). We find that BSPs
are accreted within a broad range of infall times, from 1.6 to 10 Gyr ago, with
only 25 percent accreted within the last 5 Gyrs; thus most BSPs correspond to
relatively early accretion events. We also find that 37 percent of the BSPs
survive to the present day. The median infall times for surviving and disrupted
BSPs are 5.6 and 6.7 Gyr, respectively. We find a clear relation between infall
time and infall mass of the BSPs, such that more massive progenitors tend to be
accreted at later times. However, we find that the BSPs are not, in most cases,
the dominant contributor to the accreted stellar halo of each galaxy.

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