Detection of faint broad emission lines in type 2 AGN: I. Near infrared
  observations and spectral fitting
  We present medium resolution near infrared spectroscopic observations of 41
obscured and intermediate class AGN (type 2, 1.9 and 1.8; AGN2) with redshift
$z \lesssim$0.1, selected from the Swift/BAT 70-month catalogue. The
observations have been carried out in the framework of a systematic study of
the AGN2 near infrared spectral properties and have been executed using
ISAAC/VLT, X-shooter/VLT and LUCI/LBT, reaching an average S/N ratio of
$\sim$30 per resolution element. For those objects observed with X-shooter we
also obtained simultaneous optical and UV spectroscopy. We have identified a
component from the broad line region in 13 out of 41 AGN2, with FWHM ${\rm >
800 }$ km/s. We have verified that the detection of the broad line region
components does not significantly depend on selection effects due to the
quality of the spectra, the X-ray or near infrared fluxes, the orientation
angle of the host galaxy or the hydrogen column density measured in the X-ray
band. The average broad line region components found in AGN2 has a
significantly (a factor 2) smaller FWHM if compared with a control sample of
type 1 AGN.
