Deep near-infrared imaging of the HE0450-2958 system
  The QSO HE0450-2958 and the companion galaxy with which it is interacting,
both ultra luminous in the infrared, have been the subject of much attention in
recent years, as the quasar host galaxy remained undetected. This led to
various interpretations on QSO and galaxy formation and co-evolution, such as
black hole ejection, jet induced star formation, dust obscured galaxy, or
normal host below the detection limit. We carried out deep observations in the
near-IR in order to solve the puzzle concerning the existence of any host. The
object was observed with the ESO VLT and HAWK-I in the near-IR J-band for 8
hours. The images have been processed with the MCS deconvolution method
(Magain, Courbin & Sohy, 1998), permitting accurate subtraction of the QSO
light from the observations. The compact emission region situated close to the
QSO, called the blob, which previously showed only gas emission lines in the
optical spectra, is now detected in our near-IR images. Its high brightness
implies that stars likely contribute to the near-IR emission. The blob might
thus be interpreted as an off-centre, bright and very compact host galaxy,
involved in a violent collision with its companion.
