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arXiv · astro-ph/0611600

GPS radio sources: new optical observations and an updated master list

A. Labiano·P. D. Barthel·C. P. O'Dea·W. H. de Vries·I. Pérez·S. A. Baum
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Abstract

* Aims. Identify optical counterparts, address uncertain identifications and measure previously unknown redshifts of the host galaxies of candidate GPS radio sources, and study their stellar populations. * Methods. Long slit spectroscopy and deep optical imaging in the B, V and R bands, obtained with the Very Large Telescope. * Results. We obtain new redshifts for B0316+161, B0407-658, B0904+039, B1433-040, and identify the optical counterparts of B0008-421 and B0742+103. We confirm the previous identification for B0316+161, B0407-658, B0554-026, and B0904+039, and find that the previous identification for B0914+114 is incorrect. Using updated published radio spectral information we classify as non GPS the following sources: B0407-658, B0437-454, B1648+015. The optical colors of typical GPS sources are consistent with single instantaneous burst stellar population models but do not yield useful information on age or metallicity. A new master list of GPS sources is presented.

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A. Labiano, P. D. Barthel, C. P. O'Dea, W. H. de Vries, I. Pérez, S. A. Baum. 2006-11-19. GPS radio sources: new optical observations and an updated master list. https://doi.org/10.1051/0004-6361%3A20066183

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