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Sonali K. Kadam

Publications and source records attributed to Sonali K. Kadam.

2 recordsLinked to original sources

Evidence of sloshing-driven mini-halo formation in the cool-core cluster RXCJ1558.3-1410

Radio mini-halos are perplexing features, typically hosted by X-ray cool-core galaxy clusters. Understanding the connection between thermal X-ray and non-thermal radio emission is key to uncovering their origin. Here, we present a multiwavelength study of the cool-core cluster RXCJ1558.3-1410 using archival Chandra X-ray and wideband uGMRT radio data (Bands 3, 4 and 5). Our improved analysis confirms a previously known X-ray cavity at $\sim$36 kpc south-east of the cluster centre and we report a new cavity at $\sim$42 kpc to the north-west. These cavities suggest that the AGN provides mechanical power of $\sim$$6.0 \times 10^{44}$ erg s$^{-1}$, sufficient to offset radiative cooling in the ICM. We also detect a sharp surface brightness edge at $\sim$72 kpc south-east of the centre, characterised by a temperature jump and pressure continuity, consistent with a cold front, likely caused by gas sloshing from a minor merger. Our uGMRT images reveals an interesting diffuse emission surrounding the brightest cluster galaxy (BCG), with its edge spatially coinciding with the sloshing cold front and roughly with the cooling radius. Furthermore, a low star formation rate and uniform metal abundance up to the sloshing edge are consistent with the earlier findings of suppression of star formation and metallicity homogenisation by mixing core gas through sloshing. Finally, the spatial correlation between the mini-halo and the observed X-ray features indicates that ICM sloshing, rather than AGN feedback, plays a dominant role in powering the proposed radio mini-halo emission.

astro-ph.CO↗

Merging cold front and AGN feedback in the peculiar galaxy cluster Abell 2626

This paper presents the analysis of a combined 134 ks {\it Chandra} data of a peculiar galaxy cluster Abell 2626. This study confirms the earlier detection of the east cavity at $\sim$13 kpc and reports detection of a new cavity at $\sim$39 kpc on the west of the X-ray peak. The average mechanical power injected by the AGN outburst ${\rm P_{cav} \sim 6.6 \times 10^{44}\, erg\, s^{-1}}$ is $\sim$29 times more than required to compensate the cooling luminosity ${\rm L_{cool} = 2.30 \pm 0.02 \times 10^{43} {\rm~erg\ s}^{-1}}$. The edges in the SB on the west and south-west at $\sim$36 kpc and 33 kpc, respectively, have the gas compressions of 1.57$\pm$0.08 and 2.06$\pm$0.44 and are spatially associated with the arcs in the temperature and metallicity maps due to the merging cold fronts. The systematic study of the nuclear sources exhibited dramatic changes over the span of ten years. The NE source that emitted mostly in the soft band in the past disappeared in the recent observations. Instead, an excess emission was seen at $2.2"$ on its west and required an unrealistic line of sight velocity of $\sim$ $675\times{}c$ if is due to its movement. The count rate analysis and spectral analysis exhibited a change in the state of the SW source from a soft state to the hard due to the change in the mass accretion rate. No such spectral change was noticed for the NE source.

astro-ph.GA↗