Letter to the Editor 215GHz VLBI observations of bright Active Galactic Nuclei
نویسندگان
چکیده
We report the detection of 6 active galactic nuclei, and also the marginal detection of the galactic center radio source SGRA*, in 215GHz VLBI observations between the IRAM 30m telescope on Pico Veleta and one 15m antenna of the IRAM Plateau de Bure interferometer (∼ 0.3mas fringe spacing). In this (second) 1.4mm VLBI-experiment we find source dependent ratios between the total and correlated flux densities in the range of 10–35%, indicating partly resolved brightness distributions on sub-milliarcsecond scales. In view of the calibration uncertainties and the limited uv-coverage at this high frequency this needs further confirmation. The present detection limit of∼ 0.4− 0.5 Jy opens the possibility for more extended 1.4mm VLBI experiments, in particular with phased millimeter arrays.
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