ИСТИНА

Since the discovery of the first giant low-surface brightness galaxy (GLSBg) Malin 1, astronomers were intrigued to find more disk galaxies of this size. Up until recently, the search for them was limited by the depth of existing imaging surveys, and the sample of known GLSBgs remained small as the central surface brightness of their disks is often fainter than the sky background. Here we expand the known sample of the GLSB galaxies by extensively relying on the big data approach in the form of candidate selection through HSC and Legacy imaging surveys. We have performed precise 1D photometric profile decomposition of the 240 candidates using Maximum Likelihood and MCMC methods. Additionally, we present follow-up long-slit spectroscopic observations for candidates lacking redshift information from spectroscopic databases, obtained with the Tillinghast telescope (FLWO), NTT (ESO), and the 2.5m telescope (CMO). We present the updated value for the volume density of GLSBg's as well as expand the class of these galaxies by 20 new objects, which is 19% of the known class size. Thanks to the HSC and Legacy surveys, through the search for GLSBgs we were able to establish their coexistence with compact elliptical (cE) satellites, which on their own constitute a class of rare objects. This also allows us to highlight mergers as a formation scenario of GLSBgs. Our study underlines the crucial role of wide-field photometric surveys in establishing GLSB galaxies as a substantial class, rather than isolated discoveries like Malin 1.