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1. Introduction

The Compact Steep-spectrum Sources or CSSs are physically-small objects of sub-galactic dimensions. A large fraction of these, tex2html_wrap_inline1459 70%, which have somewhat symmetric structure and have been named Compact Symmetric Objects, are believed to be the young precursors of the larger sized radio sources (Fanti et al. 1995; Readhead et al. 1996). A minority of CSSs shows a complex morphology or strongly asymmetric emission with respect to the core. The structures and sizes of these are probably affected by the ambient gas near the nucleus of the parent optical object (Pearson et al. 1985; Fanti et al. 1990; Saikia et al. 1995).

Most CSSs show low percentage polarizations (less than tex2html_wrap_inline1459 1tex2html_wrap_inline1463) at or below 5 GHz (Saikia et al. 1987). The polarization properties of CSSs at frequencies above 5 GHz have been investigated recently by a number of authors (for example, see Junor et al. 1996 and references therein). Although several well-known members of this class have low rotation measure (RM), radio polarimetric surveys (Kato et al. 1987; Taylor et al. 1992; Inoue et al. 1995) have shown that many of the sources with high RM (>700 rad m-2) are CSSs. VLA observations by Mantovani et al. (1994) and Junor et al. (1996) on selected samples of CSSs have revealed several objects with large RM.

In this paper we present VLA A-array observations at 8.4 and 15 GHz of 8 CSSs, 3 of which are of subarcsec dimensions while the remaining 5 are medium sized objects. We derive their polarization properties, and compare these with our earlier observations of CSSs. These data complete the information about a sample of sources selected because there were indications (detection of low frequency variability, spectral index turnovers around 100 MHz) they were compact objects (Mantovani et al. 1992).

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