| Abstract | The H I emission from 17 nearby spiral and irregular galaxies has been studied with the MK II radio telescope to provide integrated H I flux densities to an accuracy of 10 per cent or better. Observations were made at a grid of points extending to the limits of each galaxy. These were used to derive the integrated spectrum, the extent and position angle of the line of isovelocity centroids and the systemic velocity for each galaxy. An indicative total mass was estimated directly from the H I observations which agreed well with the value derived by other observers from rotation curves. This provides a simple H I technique for measuring total mass for any spiral or irregular galaxy. These new results gave values for the ratios of neutral hydrogen mass to luminosity, neutral hydrogen to total mass, and total mass to luminosity, which showed less scatter within each morphological type as compared with previous investigations. |
