The presence of non-thermal electrons and large scale magnetic fields in the intra-cluster medium (ICM) is known through the detection of mega-parsec (Mpc) scale diffuse radio synchrotron emission. Although a significant amount of progress in finding new diffuse radio sources has happened in the last decade, most of the investigation has been constrained towards massive low-redshift clusters. In this work, we explore clusters with redshift $z>0.3$ in search of diffuse radio emission, at 325 MHz with the Giant Metrewave Radio Telescope (GMRT). This campaign has resulted in the discovery of 2 new radio halos (SPT-CL J0013-4906 and SPT-CL J0304-4401) along with 2 other detections (SPT-CL J2031-4037 and SPT-CL J2248-4431), previously reported (at 325 MHz) in the literature. In addition, we detect a halo candidate in 1 cluster in our sample, and upper limits for halos are placed in 8 clusters where no diffuse emission is detected. In the $P_{1.4} - L_\mathrm{X}$ plane, the detected halos follow the observed correlation, whereas the upper limits lie above the correlation line, indicating the possibility of future detection with sensitive observations.

中文翻译：

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使用 GMRT 对南极望远镜 SZ 选择的星团进行低频射电晕调查

通过探测百万秒差距 (Mpc) 尺度的漫射无线电同步加速器发射，可以知道簇内介质 (ICM) 中存在非热电子和大规模磁场。尽管在过去十年中在寻找新的漫射射电源方面取得了重大进展，但大部分调查都局限于大规模的低红移星团。在这项工作中，我们使用巨型米波射电望远镜 (GMRT) 在 325 MHz 下探索红移 $z>0.3$ 的星团，以寻找漫射射电发射。该活动导致发现了 2 个新的无线电晕圈（SPT-CL J0013-4906 和 SPT-CL J0304-4401）以及其他 2 个探测结果（SPT-CL J2031-4037 和 SPT-CL J2248-4431），此前报道（在 325 MHz）在文献中。此外，我们在样本中的 1 个集群中检测到一个候选晕圈，光晕的上限设置在 8 个未检测到漫射发射的簇中。在 $P_{1.4} - L_\mathrm{X}$ 平面中，检测到的光晕遵循观察到的相关性，而上限位于相关性线以上，表明未来有可能通过敏感观察进行检测。