NGC 7213 ATCA 5.5 and 9GHz and Swift/XRT obs.

The two knots exhibit nearly identical flux densities and flat radio spectra from 300MHz up to at least 5.5GHz, with no significant spectral or geometric asymmetry. ATCA observations confirm the flat spectra at higher frequencies. The LBA monitoring shows that the nuclear radio source remains unresolved at all epochs, constraining the 8 GHz emission to sub-parsec scales.

Significant variability is detected on both decade-long timescales, relative to archival LBA data, and on month-long timescales during our monitoring, with a flux-density increase of ~40mJy over six months. The symmetry, spectra, and physical properties of the kiloparsec-scale knots strongly support their interpretation as compact termination shocks of a weak or intermittent jet launched by the LLAGN in NGC 7213 and confined by the dense, disturbed interstellar medium of the host galaxy.

The unresolved yet variable parsec-scale core traced by the LBA indicates that the observed high-frequency radio variability originates in the innermost jet region, which is likely linked to the recent increase in nuclear activity. NGC 7213 thus provides a nearby example of how weak jets in low-accretion AGN can produce both compact nuclear variability and symmetric kiloparsec-scale structures when interacting with complex environments.