VLA and Trieste observations of type I storms, type IV and pulsations

A prime objective of this experiment was to determine whether type I or IV sources at 333 MHz contain features of small (arcsec) scale. With the VLA, our resolution was better than 4 arcsec. However, we never observed any structure of size smaller than about 30 arcsec, with the typical source sizes being between about 40 arcsec and 90 arcsec. Many observations were simultaneous with the Trieste Astronomical Observatory records at 327 MHz. The observations were made on two days in November 1988. On November 8 the observations were of a type I storm about two hours after a major flare. On November 14 they were mostly of the main phase of a type IV event, including pulsations of a kind rarely seen, strongly circularly polarized, and having a well-defined period of about 12 s. The size of the pulsating source was about 40 arcsec by 60 arcsec, and the brightness temperature was about 10 exp 9 K. We compare these pulsations with those observed earlier.