Speaker
Description
Context: Abell2146 is a merging galaxy cluster with two shock fronts: a bow shock in front of the subcluster A2146-A and a slower upstream shock behind the main cluster A2146-B (Rusell et al. 2010). Despite deep GMRT observations at 325 MHz and JVLA observations at 1.4 GHz suggesting the potential presence of a radio relic, its existence in the outskirts of the merging cluster Abell 2146 remains unclear.
Aim: To confirm and characterize the presence of a radio relic in the outskirts of the merging Abell 2146 cluster using recently available 230-470 MHz archival data from the JVLA.
Methods: This research utilized the NRAO CASA software (McMullin et al., 2007) to process the newly available archival JVLA 230–470 MHz observation data of the Abell 2146 galaxy cluster. The dataset, obtained from the NRAO Science Archive, was initially flagged to remove corrupted data. The calibrator visibilities underwent first-generation calibration (1GC), and the calibration solutions were validated by reapplying them to the calibrator sources before being transferred to the target field. The calibrated target visibilities were Fourier transformed to produce a dirty image, which was shallowly cleaned. The resulting model image was then used to self-calibrate the target data, followed by deeper deconvolution. Any remaining strong or problematic sources were corrected using third-generation calibration (3GC). Compact sources were subsequently subtracted, and the residual visibilities were imaged using Briggs and natural weighting to successfully reveal the candidate radio relic.
Results: The 230–470 MHz JVLA data reveal diffuse, steep-spectrum radio
emission in the outskirts of Abell 2146, confirming the presence of a radio relic produced by shock-accelerated electrons.
| Stream | Science or Engineering |
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