The subset of compact extragalactic radio sources which exhibit bright
mm-wavelength (
) emission includes many of the most active
and interesting objects in the radio sky. These sources usually
exhibit flat or inverted spectra (
), which are modeled in the context of nuclear jets
as a cone of partially optically-thick synchrotron emission with the
number density of relativistic particles and magnetic field strength
increasing inwards towards an active galactic nucleus (Blandford &
Konigl 1979). High-frequency single-dish monitoring studies (e.g.
Brown et al. 1989; Valtaoja et al. 1992a;
Tornikoski et al. 1993; Tornikoski et al. 1996)
and ground-based VLBI observations (now routinely available with the
Coordinated Millimeter VLBI Array) are providing important information to
constrain models of the physical conditions and shock-emission mechanisms
in these sources (Marscher & Gear 1985; Valtaoja et al.
1992b).
Bright compact mm radio sources can also be used as phase calibrators for interferometer arrays. Planned "fast-switching'' schemes involve regular scans of a nearby calibrator source to derive antenna-based phase corrections to reduce or remove the effects of the wet and dry troposphere, and geometric/electronic delays (Holdaway et al. 1995). These schemes require dense grids of bright sources with accurate positions, as residual phase errors increase rapidly with source-calibrator separation and slew time. A survey of 418 northern and equatorial flat and steep-spectrum calibrator candidates was made by Holdaway et al. (1994) using the NRAO 12m telescope; in this paper we present the results of a 2 & 3mm continuum survey of 79 southern radio sources, made using the Swedish-ESO Submillimetre Telescope (SEST). The primary goals of this experiment were to catalog bright mm radio sources in the southern sky suitable for use as pointing and/or phase calibrators, and to identify interesting sources for follow-up radio and optical observations.