Yuan et al. present the first multi-band centimeter detection of POX 52, a nearby dwarf galaxy believed to harbor a robust intermediate mass black hole (IMBH). We conducted the deep observations using the Australia Telescope Compact Array (ATCA), spanning frequencies from 4.5 to 10 GHz, as well as the sensitive observations from the Karl G. Jansky Very Large Array (VLA) operating in its most extended A-configuration at S band (2–4 GHz) and C band (4–8 GHz). In the ATCA observations, the source shows a compact morphology, with only one direction marginally resolved. The higher resolution of the VLA allowed us to slightly resolve the source, fitting it well with a two-dimensional Gaussian model. The detected radio emission confirms the presence of Active Galactic Nucleus (AGN) activity, indicating either a low-power jet or AGN-driven winds/outflows. Our dual-epoch observations with ATCA and VLA, together with previous non-detection flux density upper limits, reveal radio emission variability spanning two decades. In addition, we find that POX 52 aligns well with the low-mass extension of the fundamental plane for high-accretion, radio-quiet massive AGNs.

The image above shows the naturally weighted CLEAN map of POX 52 observed by ATCA and VLA, centered at the radio positions obtained by model fitting. Contours in the map are plotted at multiples of −1, 1, √2, 2, 2√2, 4, 4√2, 8, 8√2, and 16 × 3σ, where σ is the local rms noise. The off-source background noise of each observation is 11.4, 8.2, 4.8, and 3.0 μJy beam⁻¹, respectively. The white ellipses in the lower left corner of each panel represent the FWHM of the restoring beam. The plus sign indicates the optical center obtained from Gaia DR3 (Gaia Collaboration et al. 2023).