Probing the History of the Galaxy Assembly of the Counter-rotating Disk Galaxy PGC 66551

Understand

Stellar counter-rotation in disk galaxies directly relates to the complex phenomenon of the disk mass assembly believed to be driven by external processes, such as accretion and mergers.

• The detailed study of such systems makes it possible to reveal the source of external accretion and establish the details of this process.
• In this paper, we investigate the galaxy PGC 66551 (MaNGA ID 1-179561) which hosts two large-scale counter-rotating (CR) stellar disks identified in the Sloan Digital Sky Survey MaNGA data and then confirmed using deep follow-up spectroscopy with the 10m Southern African Large Telescope.
• We measured the properties of ionized gas and stellar populations of both CR disks in PGC 66551.