HI observations of nearby galaxies

Abstract

We carried out a systematic search for nearby dwarf galaxies in the northern sky based on POSS-II film copies. As a result we present a list of 101 nearby dwarf galaxy candidates mainly of low surface brightness which have angular diameters . About two thirds of the objects are new discoveries. This sample is considered as a supplement to the 163 northern dwarf galaxy candidates (A& AS, 1998, 127, 409) which have been detected in the same declination range around the known Local Volume galaxies and to the 78 dwarf galaxy candidates (A& AS, 1999, 135, 221) in the Local Void region. All the galaxies were observed in Hi with the 100-m Effelsberg radio telescope with a detection rate of 46% . The sample of detected galaxies has the following median parameters: radial velocity km s-1, Hi line width km s-1, absolute blue magnitude mag, linear diameter kpc, hydrogen mass-to-luminosity ratio , and the HI mass-to-total mass ratio .