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arXiv · astro-ph/0303506

Keck Spectroscopy of 4 QSO Host Galaxies

Abstract

We present optical spectroscopy of the host galaxies of 4 QSO's: PG1444+407, PKS 2349-147, 3C 323.1, and 4C 31.63 having a redshift range (0.1 < z < 0.3). The spectra were obtained at the Keck Observatory with the LRIS instrument offset 2-4 arcseconds from the nucleus at several position angles in each galaxy. The objects close to 3C 323.1 and PKS 2349-147 have the same redshifts of their nearby QSOs and appear to be the nuclei of galaxies in the final states of merging with the host galaxies. The spectra of the hosts show some variety: PKS 2349-147 and 3C 323.1 show strong off-nuclear emission lines plus stellar absorption features, while the other two show only stellar absorption. PKS 2349-147 and PG 1444+407 have a mixture of old and moderately young stars, while 4C 31.63 has the spectrum of a normal giant elliptical, which is very rare in our larger sample. The spectrum of the host of 3C 323.1 appears to dominated by older stars, though our data for it are of lower quality. The redshifts of the off-nucleus emission lines and stellar components are very close to those of the associated QSOs.

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BibTeXRIS

J. S. Miller, A. I. Sheinis. 2003-03-22. Keck Spectroscopy of 4 QSO Host Galaxies. https://doi.org/10.1086/375153

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