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arXiv · 0709.3743

Slit and integral-field optical spectroscopy of the enigmatic quasar HE0450-2958

G. Letawe·P. Magain·F. Courbin
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Abstract

Interest in the quasar HE0450-2958 arose following the publication of the non-detection of its expected massive host, leading to various interpretations. This article investigates the gaseous and stellar contents of the system through additional VLT/FORS slit spectra and integral field spectroscopy from VLT/VIMOS. We apply our MCS deconvolution algorithm on slit spectra for the separation of the QSO and diffuse components, and develop a new method to remove the point sources in Integral Field Spectra, allowing extraction of velocity maps, narrow-line images, spatially resolved spectra or ionization diagrams of the surroundings of HE0450-2958. The whole system is embedded in gas, mostly ionized by the QSO radiation field and shocks associated with radio jets. The observed gas and star dynamics are unrelated, revealing a strongly perturbed system. Despite longer spectroscopic observations, the host galaxy remains undetected.

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G. Letawe, P. Magain, F. Courbin. 2008-01-04. Slit and integral-field optical spectroscopy of the enigmatic quasar HE0450-2958. https://doi.org/10.1051/0004-6361:20078725

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