Speaker
Description
Context: The Perseus cluster (Abell 426) is the brightest cool-core galaxy cluster and hosts a complex mix of AGN-inflated bubbles, mini-halo emission, and weak shocks. Unlike classical merging clusters, Perseus shows low X-ray Mach numbers ($\mathcal{M}\sim1.2$--$1.6$), raising questions about how particles are accelerated in a non-merging environment where standard Diffusive Shock Acceleration (DSA) is expected to be inefficient.
Aim: Using new JVLA S- and C-band observations across B, C, and D configurations, our goal is to obtain the first complete high-frequency, multi-scale view of the Perseus core. We aim to characterise its diffuse emission, investigate possible shock-driven re-acceleration, and compare radio- and X-ray-derived Mach numbers using a reference sample of relics to derive an empirical relation applicable to Perseus.
Methods: We process the data using standard radio-interferometric steps, including RFI removal, basic flagging, and flux calibration. After applying the calibration to the Perseus data, we create images at multiple spatial scales using uv-range filtering and Briggs weighting. We then refine the images through self-calibration. Finally, compact AGN emission is modelled and removed to reveal the faint diffuse structures.
Results: Preliminary imaging shows hints of faint diffuse emission in the Perseus core, with features that may relate to the mini-halo, AGN cavities, and the NGC~1272 region. After compact-source subtraction, the residual maps suggest weak extended structures across multiple scales. Using our calibrated reference sample of relic Mach numbers, the radio-based estimates remain consistent with weak shocks in Perseus, indicating possible low-Mach re-acceleration activity within the cool-core environment.
| Stream | Science or Engineering |
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