Open AccessThe nature of the HE0450−2958 system
Author(s) -
Merritt David,
StorchiBergmann Thaisa,
Robinson Andrew,
Batcheldor Dan,
Axon David,
Cid Fernandes Roberto
Publication year - 2006
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1111/j.1365-2966.2006.10093.x
Subject(s) - physics , astrophysics , quasar , galaxy , astronomy , redshift , black hole (networking) , luminosity , interacting galaxy , galaxy merger , luminous infrared galaxy , computer network , routing protocol , routing (electronic design automation) , computer science , link state routing protocol
Magain et al. argued that the host galaxy of the quasar in HE0450−2958 is substantially underluminous given the quasar brightness. Using kinematical information from the spectra of the quasar and the companion galaxy, an ultraluminous infrared galaxy, we test the hypothesis that the black hole powering the quasar was ejected from the companion galaxy during a merger. We argue that the ejection model is unlikely, since the kick velocity required to remove the black hole from the galaxy is ≳500 km s −1 , inconsistent with the presence of narrow emission‐line gas at the same redshift as the quasar nucleus. We also show that the quasar in HE0450−2958 has the spectral characteristics of a narrow‐line Seyfert 1 galaxy and calculate a mass for its black hole that is roughly an order of magnitude smaller than that estimated by Magain et al. The predicted luminosity of the host galaxy is then consistent with the upper limits inferred by those authors.