On the accretion of a new group of galaxies onto Virgo: I. Internal kinematics of nine in-falling dEs. (arXiv:2007.05021v1 [astro-ph.GA])
<a href="http://arxiv.org/find/astro-ph/1/au:+Bidaran_B/0/1/0/all/0/1">Bahar Bidaran</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Pasquali_A/0/1/0/all/0/1">Anna Pasquali</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Lisker_T/0/1/0/all/0/1">Thorsten Lisker</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Coccato_L/0/1/0/all/0/1">Lodovico Coccato</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Falcon_Barroso_J/0/1/0/all/0/1">Jesus Falcón-Barroso</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ven_G/0/1/0/all/0/1">Glenn van de Ven</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Peletier_R/0/1/0/all/0/1">Reynier Peletier</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Emsellem_E/0/1/0/all/0/1">Eric Emsellem</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Grebel_E/0/1/0/all/0/1">Eva K. Grebel</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Barbera_F/0/1/0/all/0/1">Francesco La Barbera</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Janz_J/0/1/0/all/0/1">Joachim Janz</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Sybilska_A/0/1/0/all/0/1">Agnieszka Sybilska</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Vijayaraghavan_R/0/1/0/all/0/1">Rukmani Vijayaraghavan</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Gallagher_J/0/1/0/all/0/1">John Gallagher III</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Gadotti_D/0/1/0/all/0/1">Dimitri A. Gadotti</a>
Galaxy environment has been shown to play an important role in transforming
late-type, star-forming galaxies to quiescent spheroids. This transformation is
expected to be more severe for low-mass galaxies (M < $10^{10}$ (M_odot)) in
dense galaxy groups and clusters, mostly due to the influence of their past
host halos (also known as pre-processing) and their present-day environments.
For the first time, in this study, we investigate a sample of nine early-type
dwarf galaxies (dEs) that were accreted as a likely bound group onto the Virgo
galaxy cluster about 2-3 Gyr ago. Considering this special condition, these
nine dEs may provide a test bed for distinguishing between the influence of the
Virgo galaxy cluster and the effects of the previous host halo on their current
properties. Specifically, we use VLT/MUSE integral-field unit spectra to derive
their kinematics and specific angular momentum ($lambda_{R}$) profiles. We
observe a spread in the $lambda_{R}$ profiles of our sample dEs, finding that
the $lambda_{R}$ profiles of half of them are as high as those of low-mass
field galaxies. The remaining dEs exhibit $lambda_{R}$ profiles as low as
those of Virgo dEs that were likely accreted longer ago. Moreover, we detect
nebular emission in one dE with a gas velocity offset suggesting ongoing gas
stripping in Virgo. We suggest that the low-$lambda_{R}$ dEs in our sample
were processed by their previous host halo, prior to their infall to Virgo, and
that the high-$lambda_{R}$ dEs may be experiencing ram pressure stripping in
Virgo.
Galaxy environment has been shown to play an important role in transforming
late-type, star-forming galaxies to quiescent spheroids. This transformation is
expected to be more severe for low-mass galaxies (M < $10^{10}$ (M_odot)) in
dense galaxy groups and clusters, mostly due to the influence of their past
host halos (also known as pre-processing) and their present-day environments.
For the first time, in this study, we investigate a sample of nine early-type
dwarf galaxies (dEs) that were accreted as a likely bound group onto the Virgo
galaxy cluster about 2-3 Gyr ago. Considering this special condition, these
nine dEs may provide a test bed for distinguishing between the influence of the
Virgo galaxy cluster and the effects of the previous host halo on their current
properties. Specifically, we use VLT/MUSE integral-field unit spectra to derive
their kinematics and specific angular momentum ($lambda_{R}$) profiles. We
observe a spread in the $lambda_{R}$ profiles of our sample dEs, finding that
the $lambda_{R}$ profiles of half of them are as high as those of low-mass
field galaxies. The remaining dEs exhibit $lambda_{R}$ profiles as low as
those of Virgo dEs that were likely accreted longer ago. Moreover, we detect
nebular emission in one dE with a gas velocity offset suggesting ongoing gas
stripping in Virgo. We suggest that the low-$lambda_{R}$ dEs in our sample
were processed by their previous host halo, prior to their infall to Virgo, and
that the high-$lambda_{R}$ dEs may be experiencing ram pressure stripping in
Virgo.
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