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arXiv · 1110.1794

Radio observations of the first three-month Fermi-AGN at 4.8 GHz

Xiang Liu·Hua-Gang Song·Jun Liu·Zhen Ding·Nicola Marchili·Thomas P. Krichbaum·Lars Fuhrmann·Anton Zensus·Tao An
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Abstract

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.

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Xiang Liu, Hua-Gang Song, Jun Liu, Zhen Ding, Nicola Marchili, Thomas P. Krichbaum, Lars Fuhrmann, Anton Zensus, Tao An. 2011-10-09. Radio observations of the first three-month Fermi-AGN at 4.8 GHz. https://doi.org/10.1088/1674-4527%2F12%2F2%2F003

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