Letter to the Editor 215GHz VLBI observations of bright Active Galactic Nuclei

نویسندگان

  • T. P. Krichbaum
  • D. A. Graham
  • A. Greve
  • J. E. Wink
  • J. Alcolea
  • F. Colomer
  • P. de Vicente
  • A. Baudry
  • J. Gómez-Gónzalez
  • M. Grewing
  • A. Witzel
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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تاریخ انتشار 1997