B and R magnitudes for spiral galaxies

It is an observational fact that bulges of spiral galaxies contain a high fraction of old and metal-rich stars. Following this observational fact, we have investigated the...螺旋星系核球（bulge）包含高比例的老年富金属恒星，这是一项观测事实。基于该观测事实，我们已对……开展了相关研究。