Deep H <scp>i</scp> mapping of M 106 group with FAST

ABSTRACT We used Five-hundred-meter Aperture Spherical radio Telescope (FAST) to conduct deep H i imaging of the entire M 106 group region, and have discovered a few new H i filaments and clouds. Three H i clouds/filaments are found in a region connecting DDO 120 and NGC 4288, indicating an interaction between these two galaxies. The H i features in this region suggest that DDO 120 is probably the origin of the H i stream extending from the northern end of NGC 4288 to M 106. This structure is similar to the Small–Large Magellanic Cloud stream, but much longer, about 190 kpc. Furthermore, based on the distance measurements, we have determined the satellite galaxy members of M 106. With an absolute magnitude cutoff of $M_{B}$ = −10, we obtained a sample of 11 member satellite galaxies for M 106. Using the observed H i mass with FAST, we studied the properties of satellite galaxies in M 106 and found that satellite galaxies with lower stellar masses exhibit more significant deviations from the star-forming main sequence in their specific star formation rates. Furthermore, the relationship between the H i mass of satellite galaxies and optical diameter generally follows the field galaxies relation. We discuss the possible mechanisms leading to the quenching in the M 106 group based on the new data from FAST.