  We present high resolution 240 and 607 MHz GMRT radio observations,
complemented with 74 MHz archival VLA radio observations of the Ophiuchus
cluster of galaxies, whose radio mini-halo has been recently detected at 1400
MHz. We also present archival Chandra and XMM-Newton data of the Ophiuchus
cluster. Our observations do not show significant radio emission from the
mini-halo, hence we present upper limits to the integrated, diffuse non-thermal
radio emission of the core of the Ophiuchus cluster. The XMM-Newton
observations can be well explained by a two-temperature thermal model with
temperatures of ~=1.8 keV and ~=9.0 keV, respectively, which confirms previous
results that suggest that the innermost central region of the Ophiuchus cluster
is a cooling core. We also used the XMM-Newton data to set up an upper limit to
the (non-thermal) X-ray emission from the cluster.
  The combination of available radio and X-ray data has strong implications for
the currently proposed models of the spectral energy distribution (SED) from
the Ophiuchus cluster. In particular, a synchrotron+IC model is in agreement
with the currently available data, if the average magnetic field is in the
range (0.02-0.3) microG. A pure WIMP annihilation scenario can in principle
reproduce both radio and X-ray emission, but at the expense of postulating very
large boost factors from dark matter substructures, jointly with extremely low
values of the average magnetic field. Finally, a scenario where synchrotron and
inverse Compton emission arise from PeV electron-positron pairs (via
interactions with the CMB), can be ruled out, as it predicts a non-thermal soft
X-ray emission that largely exceeds the thermal Bremsstrahlung measured by
INTEGRAL.
