Speaker
Description
NGC7618/UGC12491 is a major group merger in the Local Universe that has been intensively studied in the X-rays, showing a series of complex features involving both groups. Only recently, thanks to the continuous improvement in capabilities of the instrumentation, the possibility to complement the work with the study of non-thermal phenomena in the radio regime has been available.
In this poster, I will report ongoing work based on the combination of radio multi-frequency observations (LOFAR 144 MHz, GMRT at 323 and 608 MHz and JVLA in L band) and X-ray Chandra data of this rare major group merger. In the radio the two groups show different features, with NGC7618 being characterized by prominent extended radio emission at its center (on scales up to 90 kpc), and UGC12491 showing only a marginal indication of faint diffuse emission at its center. The spectral mapping of the radio emission in NGC7618 has a complex distribution, suggesting ongoing interplay between non-thermal components and the surrounding thermal gas, likely involving particle re-acceleration. By combining radio and X-ray properties we aim to understand the origin of the diffuse source in NGC7618 and the reason of its different radio properties with respect to the companion UGC12491.
