2001ApJ...549L.191M

We have obtained deep CO (1-0) observations of eight nearby, edge-on, low surface brightness (LSB) spiral galaxies using the NRAO 12 m telescope. We report detections of three of our targets at a greater than 4 σ level as well as one marginal (∼3 σ) detection. These are among the first direct detections of molecular gas in late-type, LSB spiral galaxies. Using a Galactic CO-to-H₂ conversion factor, we derive M_H2~(1.4-3.5)x10⁷ M_☉ and M_H2/M_HI_∼0.010-0.055 for the detected sources, with 3 σ upper limits of M_H2≲(0.7-5.7)x10⁷ M_☉ and M_H2/M_HI_≲0.006-0.029 for the undetected objects.