ﻻ يوجد ملخص باللغة العربية
Diffuse radio sources associated with the intra-cluster medium are direct probes of the cosmic ray electrons and magnetic fields. We report the discovery of a diffuse radio source in the galaxy cluster RXCJ0232.2-4420 (SPT-CL J0232-4421, $z=0.2836$) using 606 MHz observations with the Giant Metrewave Radio Telescope. The diffuse radio source surrounds the Brightest Cluster Galaxy in the cluster like typical radio mini-halos. However the total extent of it is $550times800$ kpc$^{2}$, which is larger than mini-halos and similar to that of radio halos. The BCG itself is also a radio source with a marginally resolved core at $7$ (30 kpc) resolution. We measure the 606 MHz flux density of the RH to be $52pm5$ mJy. Assuming a spectral index of 1.3, the 1.4 GHz radio power is $4.5 times 10^{24}$ W Hz$^{-1}$. The dynamical state of the cluster has been inferred to be relaxed and also as complex depending on the classification methods based on the morphology of the X-ray surface brightness. This system thus seems to be in the transition phase from a mini-halo to a radio halo.
We report the discovery of extended radio emission in the Phoenix cluster (SPT-CL J2344-4243, z=0.596) with the GMRT at 610 MHz. The diffuse emission extends over a region of at least 400-500 kpc and surrounds the central radio source of the Brightes
RXCJ0232.2-4420, at $z$ = 0.28, is a peculiar system hosting a radio halo source around the cool-core of the cluster. To investigate its formation and nature, we used archival {it Chandra} and XMM-textit{Newton} X-ray data to study the dynamical stat
We report on a spectral study at radio frequencies of the giant radio halo in A2142 (z=0.0909), which we performed to explore its nature and origin. A2142 is not a major merger and the presence of a giant radio halo is somewhat surprising. We perform
We investigate the possible presence of diffuse radio emission in the intermediate redshift, massive cluster PLCK G285.0-23.7 (z=0.39, M_500 = 8.39 x 10^(14) M_Sun). Our 16cm-band ATCA observations of PLCK G285.0-23.7 allow us to reach a rms noise le
We present a low-frequency view of the Perseus cluster with new observations from the Karl G. Jansky Very Large Array (JVLA) at 230-470 MHz. The data reveal a multitude of new structures associated with the mini-halo. The mini-halo seems to be influe