Diffuse , non-thermal emission in galaxy clusters is increasingly being detected in low-frequency radio surveys and images .
We present a new diffuse , steep-spectrum , non-thermal radio source within the cluster Abell 1127 found in survey data from the Murchison Widefield Array ( MWA ) .
We perform follow-up observations with the ‘ extended ’ configuration MWA Phase II with improved resolution to better resolve the source and measure its low-frequency spectral properties .
We use archival Very Large Array S-band data to remove the discrete source contribution from the MWA data , and from a power law model fit we find a spectral index of -1.83 \pm 0.29 broadly consistent with relic-type sources .
The source is revealed by the Giant Metrewave Radio Telescope ( GMRT ) at 150 MHz to have an elongated morphology , with a projected linear size of 850 kpc as measured in the MWA data .
Using Chandra observations we derive morphological estimators and confirm quantitatively that the cluster is in a disturbed dynamical state , consistent with the majority of phoenices and relics being hosted by merging clusters .
We discuss the implications of relying on morphology and low-resolution imaging alone for the classification of such sources and highlight the usefulness of the MHz to GHz radio spectrum in classifying these types of emission .
Finally , we discuss the benefits and limitations of using the MWA Phase II in conjunction with other instruments for detailed studies of diffuse , steep-spectrum , non-thermal radio emission within galaxy clusters .