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arXiv · 1702.06644

Optical Spectra of Candidate International Celestial Reference Frame (ICRF) Flat-Spectrum Radio Sources. III

O. Titov·T. Pursimo·H. M. Johnston·L. M. Stanford·R. W. Hunstead·D. L. Jauncey·K. A. Zenere
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Abstract

In extending our spectroscopic program, which targets sources drawn from the International Celestial Reference Frame (ICRF) Catalog, we have obtained spectra for about 160 compact flat-spectrum radio sources and determined redshifts for 112 quasars and radio galaxies. A further 14 sources with featureless spectra have been classified as BL Lac objects. Spectra were obtained at three telescopes: the 3.58-m ESO New Technology Telescope (NTT), and the two 8.2-m Gemini telescopes in Hawaii and Chile. While most of the sources are powerful quasars, a significant fraction of radio galaxies is also included from the list of non-defining ICRF radio sources.

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O. Titov, T. Pursimo, H. M. Johnston, L. M. Stanford, R. W. Hunstead, D. L. Jauncey, K. A. Zenere. 2017-02-22. Optical Spectra of Candidate International Celestial Reference Frame (ICRF) Flat-Spectrum Radio Sources. III. https://doi.org/10.3847/1538-3881%2Faa61fd

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