An Hα Imaging Survey of the Low Surface Brightness Galaxies Selected from the Spring Sky Region of the 40% ALFALFA H i Survey

We present a narrow H α -band imaging survey of 357 low surface brightness galaxies (LSBGs) that are selected from the spring sky region of the 40% Arecibo Legacy Fast Arecibo L -band Feed Array (ALFALFA) H i Survey. All the H α images are obtained from the 2.16 m telescope, operated by the Xinglong Observatory of the National Astronomical Observatories, Chinese Academy of Sciences. We provide the H α fluxes and derive the global star formation rates (SFRs) of LSBGs after the Galactic extinction, internal extinction, and [N ii ] contamination correction. Compared to normal star-forming galaxies, LSBGs have a similar distribution in the H i surface density (Σ H i ), but their SFRs and star formation surface density (Σ SFR ) are much lower. Our results show that the gas-rich LSBGs selected from the ALFALFA survey obviously deviate from the Kennicutt–Schmidt law, in the relation between the star formation surface density (Σ SFR ) and the gas surface density (Σ gas ). However, they follow the extended Schmidt law well when taking the stellar mass of the galaxy into consideration.