VLBI OBSERVATIONS OF SOUTHERN EGRET IDENTIFICATIONS - II - VLBA OBSERVATIONS AND THE IMPORTANCE OF JET BENDING IN GAMMA-RAY SOURCES

We present VLBI images of six southern hemisphere radio sources that h ave been identified by EGRET as sources of greater-than-100 MeV gamma- ray emission, PKS 0521-365, PKS 1127-145, PKS 1622-253, PKS 1622-297, PKS 1730-130, and PKS 1908-201. We quantitatively investigate the sugg estion of von Montigny et al. that jet bending may be a significant fa ctor affecting the gamma-ray identification of radio-loud fiat-spectru m active galactic nuclei (AGNs), using samples of EGRET-identified and gamma-ray-quiet radio sources. From this investigation, we find evide nce to suggest that jet bending properties, as observed in parsec-scal e radio jets, are correlated with gamma-ray identification for this cl ass of source. The parsec-scale jets in gamma-ray-quiet AGNs appear to have more and larger bends than do the parsec-scale jets in EGRET-ide ntified AGNs. Caution should be exercised when interpreting these resu lts, however, since we point out that significant, but difficult to qu antify, observational biases may also be at work in these samples.