  As a well-motivated dark matter candidate, axions can be detected through the
axion-photon resonant conversion in the magnetospheres of magnetic white dwarf
stars or neutron stars. In this work, we utilize Omega Centauri, which is the
largest globular cluster in the Milky Way and is suggested to be the remnant
core of a dwarf galaxy, to probe the axion dark matter through radio signals
that originate from all the neutron stars and magnetic white dwarf stars in it.
With 100 hours of observation, the combination of SKA phase 1 and LOFAR can
effectively probe the parameter space of the axion-photon coupling
$g_{a\gamma}$ up to $10^{-14}\sim 10^{-15}~\text{GeV}^{-1}$ for the axion mass
range of $0.1\sim 30 ~\mu\text{eV}$. Depending on the choice of neutron star
evolution model, this limitation is two or three and a half orders of magnitude
higher than that of the single neutron star or magnetic white dwarf.
