Abstract
Following evidence for an east--west elongated virial ring around the Coma
galaxy cluster in a $\sim220$ GeV VERITAS mosaic, we search for corresponding
signatures in $>$GeV $\gamma$-rays from Fermi-LAT, and in soft, $\sim0.1$ keV
X-rays from ROSAT. For the ring elongation and orientation inferred from
VERITAS, we find a $3.4\sigma$ LAT excess, and detect ($>5\sigma$) the expected
signature in ROSAT bands R1 and R1+R2. The significances of both LAT and ROSAT
signals are maximal near the VERITAS ring parameters. The intensities of the
ROSAT, Fermi, and VERITAS signals are consistent with the virial shock
depositing $\sim0.3\%$ (with an uncertainty factor of $\sim3$) of its energy
over a Hubble time in a nearly flat, $p- dN_e/dE\simeq
2.0$--$2.2$ spectrum of cosmic-ray electrons. The sharp radial profiles of the
LAT and ROSAT signals suggest preferential accretion in the plane of the sky,
as indicated by the distribution of neighboring large-scale structure. The
X-ray signal gauges the compression of cosmic-rays as they are advected deeper
into the cluster.
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