Is IRAS 01072+4954 a True-Seyfert 2? Hints from Near Infrared Integral
  Field Spectroscopy
  In contrast to the predictions of the unified model, some X-ray unobscured
Seyfert 2 galaxies have been discovered in the last decade. One of them, the
starburst/Seyfert composite galaxy IRAS 01072+4954 (z=0.0236), has a typical
Type~1 X-ray emission, while its optical spectrum resembles an HII galaxy and
lacks the expected broad lines. We performed near-infrared integral-field
observations of this object with the aim to determine the nature of its nuclear
emission and to find indications for the existence or absence of a broad-line
region. Several reasons have been proposed to explain such peculiar emission.
We studied the validity of such hypotheses, including the possibility for it to
be True-Seyfert~2. We found little obscuration towards the nucleus A_V = 2.5
mag, and a nuclear star-formation rate Sigma_SFR < 11.6 Msun yr^{-1} kpc^{-2},
which is below the average in Seyferts. Unresolved hot-dust emission with T ~
1150 K seems to indicate the presence of a torus with its axis close to the
line of sight. We found that IRAS 01072+4954 hosts a low mass black hole with
an estimated mass of M_BH ~ 10^5 Msun and an upper limit of 2.5x10^6 Msun. Its
bolometric luminosity is L_bol ~ 2.5x10^{42} erg/s, which yields a high
accretion rate with an Eddington ratio ~ 0.2. If the relations found in more
massive systems also apply to this case, then IRAS 01072+4954 should show broad
emission lines with FWHM_{broad} ~(400-600) km/s. Indeed, some indications for
such narrow broad-line components are seen in our data, but the evidence is not
yet conclusive. This source thus seems not to be a True-Seyfert 2, but an
extreme case of a narrow line Seyfert 1, which, due to the faintness of the
active nucleus, does not have strong FeII emission in the optical.
