H I-observations of galaxies in the zone of avoidance in Puppis

Abstract

76 apparently faint galaxies in the galactic plane in Puppis (1 almost-equal-to 245-degrees, Absolute value of b &lt;+/- 8-degrees) were observed with the 100 m radio telescope in Effelsberg. The detection rate is quite high (38 certain, 1 confused and 4 possible detections). It depends neither on galactic latitude nor on magnitude, underscoring the fact that H I-line measurements are indeed a powerful method of obtaining redshifts for highly obscured spiral galaxies. Rough corrections of the magnitudes for extinction show that most of the galaxies are actually quite bright ([m(B)0] less-than-or-equal-to 14.5m). The majority of the galaxies were detected at fairly low velocities (v0 &lt;3000 km s-1. These are concentrated in four groups. The most massive one (at v0 almost-equal-to 1450 km s-1) turns out to form part of a wall that crosses the galactic plane vertically. These newly disclosed nearby groups and filaments might contribute to the peculiar motion of the Local Group. A more distant filament at v0 almost-equal-to 5000 km s-1 is indicated in the distribution as well and seems connected to outlying extragalactic large-scale structures.The global properties of the observed galaxies such as total mass, H I-mass and M(H I)/L(B) are normal in every respect and reflect the properties of a typical nearby sample of galaxies. The infrared properties of the 34 galaxies listed in the IRAS PSC such as the f100/f60 color temperature and the ratio of the blue to infrared flux are found to be representative of an optically selected galaxy sample [[log(f100/f60)] = 0.53, [log (L(FIR)/L(B)0)]= -0.34], and the infrared luminosity L(FIR) to correlate with the H I-mass.</p