The Resolved Sunyaev–Zel’dovich Profiles of Nearby Galaxy Groups. (arXiv:2105.01123v1 [astro-ph.CO])
<a href="http://arxiv.org/find/astro-ph/1/au:+Pratt_C/0/1/0/all/0/1">C.T. Pratt</a> (1), <a href="http://arxiv.org/find/astro-ph/1/au:+Qu_Z/0/1/0/all/0/1">Z. Qu</a> (1), <a href="http://arxiv.org/find/astro-ph/1/au:+Bregman_J/0/1/0/all/0/1">J.N. Bregman</a> (1) ((1) University of Michigan)

Much of the baryons in galaxy groups are thought to have been driven out to
large distances ($gtrsim$$R_{500}$) by feedback, but there are few
constraining observations of this extended gas. This work presents the resolved
Sunyaev–Zel’dovich (SZ) profiles for a stacked sample of 10 nearby galaxy
groups within the mass range log$_{10}(M_{500}[M_{odot}]) = 13.6 -13.9$. We
measured the SZ profiles using the publicly available $y$-map from the Planck
Collaboration as well as our own $y$-maps constructed from more recent versions
of $Planck$ data. The $y$-map extracted from the latest data release yielded a
significant SZ detection out to 3 $R_{500}$. In addition, the stacked profile
from these data were consistent with simulations that included AGN feedback.
Our best-fit model using the latest $Planck$ data suggested a baryon fraction
$approx 5.6%$ within $R_{500}$. This is significantly lower than the cosmic
value of $approx 16%$, supporting the idea that baryons have been driven to
large radii by AGN feedback. Lastly, we discovered a significant ($sim
3sigma$) “bump” feature near $sim 2$ $R_{500}$ that is most likely the
signature of internal accretion shocks.

Much of the baryons in galaxy groups are thought to have been driven out to
large distances ($gtrsim$$R_{500}$) by feedback, but there are few
constraining observations of this extended gas. This work presents the resolved
Sunyaev–Zel’dovich (SZ) profiles for a stacked sample of 10 nearby galaxy
groups within the mass range log$_{10}(M_{500}[M_{odot}]) = 13.6 -13.9$. We
measured the SZ profiles using the publicly available $y$-map from the Planck
Collaboration as well as our own $y$-maps constructed from more recent versions
of $Planck$ data. The $y$-map extracted from the latest data release yielded a
significant SZ detection out to 3 $R_{500}$. In addition, the stacked profile
from these data were consistent with simulations that included AGN feedback.
Our best-fit model using the latest $Planck$ data suggested a baryon fraction
$approx 5.6%$ within $R_{500}$. This is significantly lower than the cosmic
value of $approx 16%$, supporting the idea that baryons have been driven to
large radii by AGN feedback. Lastly, we discovered a significant ($sim
3sigma$) “bump” feature near $sim 2$ $R_{500}$ that is most likely the
signature of internal accretion shocks.

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