| Abstract: | Galaxy clusters have the potential to accelerate cosmic rays (CRs) to
ultra-high energies via accretion shocks or embedded CR acceleration sites. CRs
with energies below the Hillas condition will be confined within the cluster
and will eventually interact with the intracluster medium (ICM) gas to produce
secondary neutrinos and $gamma$ rays. Using 9.5 years of muon-neutrino track
events from the IceCube Neutrino Observatory, we report the results of a
stacking analysis of 1094 galaxy clusters, with masses $gtrsim 10^{14}$
( extup{M}_odot) and redshifts between 0.01 and $sim$1, detected by the
{it Planck} mission via the Sunyaev-Zeldovich (SZ) effect. We find no evidence
for significant neutrino emission and report upper limits on the cumulative
unresolved neutrino flux from galaxy clusters after accounting for the
completeness of the catalog, assuming three different weighting scenarios for
the stacking and three different power-law spectra. Weighting the sources
according to mass and distance, we set upper limits at $90\%$ confidence level
that constrain the flux of neutrinos from galaxy clusters to be no more than
$4.6\%$ of the diffuse IceCube observations at 100 TeV, assuming an unbroken
$E^{-2.5}$ power-law spectrum. |
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