High-resolution rotation curves of low surface brightness galaxies. I. Data

We present long-slit H alpha observations of 50 low surface brightness gala xies. Of these, 36 are of sufficient quality to form rotation curves. These data provide a large increase in the number of low surface brightness gala xies for which accurate rotation curves are available. They also represent an order-of-magnitude improvement in spatial resolution over previous 21 cm studies (1 " -2 " instead of 13 " -45 "). The improved resolution and accu racy of the data extend and strengthen the scientific conclusions previousl y inferred from 21 cm data.