Swift UVOT stars survey. II. RR Lyrae in M3 and M15

We present the first results of a Near-UltraViolet (NUV) survey of RR Lyrae stars from the Ultraviolet Optical Telescope (UVOT) on board the Swift Gamma-ray Burst Mission. It is...本研究报道了搭载于Swift伽马射线暴任务的紫外光学望远镜（UVOT）开展的天琴座RR型变星近紫外（NUV）巡天的首批成果。