Radio observations of the first three-month Fermi-AGN at 4.8 GHz
  Using the Urumqi 25m radio telescope, sources from the first three-month
Fermi-LAT detected AGN catalog with declination >0 were observed in 2009 at 4.8
GHz. The radio flux density appears to correlate with the gamma-ray intensity.
Intra-day variability (IDV) observations were performed in March, April and May
in 2009 for selected 42 gamma-ray bright blazars, and 60% of them show evident
flux variability at 4.8 GHz during the IDV observations, the IDV detection rate
is higher than that in previous flat-spectrum AGN samples. The IDV appears more
often in the VLBI-core dominant blazars, and the non-IDV blazars show
relatively `steeper' spectral indices than the IDV blazars. Pronounced
inter-month variability has been found in two BL Lac objects: J0112+2244 and
J0238+1636.
