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Date and Time of the Query: 2019-06-19 T22:55:03 PDT
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Notes for object 2MASX J01500266-0725482

5 note(s) found in NED.


1. 2008MNRAS.390.1241B
Re:IRAS F01475-0740
4.1 IRASF 01475-0740 The XMM-Newton spectrum of IRASF 01475-0740 is well fitted
by a power-law absorbed by a column of N_H_= 4.1*10^21^cm^-2^. While this
will produce some reddening and extinction in the optical, it is unlikely to be
sufficient to suppress the optical broad lines entirely unless the absorber has
an anomalously high dust-to-gas ratio (cf. MCG-6-30-15; Reynolds et al. 1997).
The X-ray spectrum also shows line emission between 6 and 7 keV. The centroid
energy of this line is not well constrained, so we assume that the emission is
from neutral iron K{alpha} at a rest energy of 6.4 keV, though it may originate
from ionized iron. A Gaussian fit to this feature with the centroid energy fixed
at 6.4 keV gives an EW of 160 eV. On the face of it, this relatively modest iron
K{alpha} EW argues against a hidden Compton thick nucleus (Bianchi et al. 2008).
We found, however, that it was possible to fit a second, heavily absorbed
component from new Monte Carlo models of X-rays in heavily obscured AGN,
incorporating line emission (Brightman et al., in preparation), similar to those
presented by e.g. Ghisellini, Haardt & Matt (1994) and Krolik, Madau & Zycki
(1994). For simplicity given the limitations of the data we fit the extreme case
of 4{pi} coverage (i.e. a spherical distribution of matter), and we constrained
the column density of the heavily absorbed component to N_H_= 2 * 10^24^
|^+65^_-0.8_ cm^-2^. Although it is not formally required in the fit, this
demonstrates a clear scenario in which the multiwavelength data can be
reconciled, as such a column is easily sufficient to suppress the direct nuclear
emission in the optical. By correcting for absorption in this heavily obscured
component, we can make another prediction of the intrinsic luminosity of the
nucleus and calculate the corresponding bolometric luminosity. This now agrees
well with estimations from L_[O III]_ and L_12{mu}m_. The XMM-Newton observation
also shows no clear signs of variability. The spectropolarimetric survey of Tran
(2003) reveals that this AGN hosts a hidden BLR, in full agreement with our
conclusion of a heavily buried nuclear contribution. The same electrons which
scatter the broad optical lines into the line of sight can then also scatter
nuclear X-rays accounting for the apparently unobscured nature of the soft
spectrum.

2. 2008MNRAS.390.1241B
Re:IRAS F01475-0740
5.3.1 IRASF 01475-0740 Bianchi et al. (2008) use the small size of the iron line
in NGC 3147 to argue against the Compton thick nature of that source. However,
IRASF 01475-0740 also shows a small iron line, but in this object we know that
heavy nuclear obscuration is occurring as shown by Tran (2003). This
spectropolarimetric study showed that IRASF 01475-0740 has broad lines in its
polarized optical spectrum, which are missing in its normal optical spectrum,
confirming that our line of sight to the nucleus is blocked by optically thick
material. We show that a Compton thick source may exhibit only a moderate iron
line if the continuum emission below 10 keV is dominated by a strong scattered
continuum or extra-nuclear emission. We demonstrated this by adding a second
component to the fit of the X-ray spectrum, with a much larger column density
than the first component, by using the iron line as a constraint. The intrinsic
hard X-ray luminosity of this second component is a factor of ~10 greater than
the observed luminosity.
Assuming that the observed hard X-ray spectrum is indeed dominated by
scattered light, we calculate an upper limit on the scattering fraction by
fixing the column density of the second component to its lower limit. The upper
limit on the scattering fraction turns out to be 50 per cent, far higher than
the typical ~3 per cent seen in Seyfert 2 galaxies (Cappi et al. 2006). Ueda et
al. (2007) observed a <1 per cent scattered fraction in two Compton thick AGN,
SWIFT J0601.98636 and SWIFT J0138.64001. They used that fraction to suggest that
these objects have a large covering fraction of the torus, or a low abundance of
the gas responsible for the scattering in those objects. The inverse could be
true for IRASF 0175-0740 - it may have a low covering fraction of the torus, or
a high abundance of the gas responsible for the scattering. Scattered components
are also often seen in reflection dominated sources (e.g. NGC 1068; Pier et al.
1994). If there is an underlying reflection component in IRASF 0175-0740, this
may also be dominated by scattered emission if the inclination angle of the
torus is very high so that only a small part of the inner wall of the torus is
directly visible and not self-obscured. This would give a very high
scattered/reflected fraction as noted for model C in Table 4.
If the line emission seen here between 6 and 7 keV in fact originates from
ionized iron, then we could be seeing reflection from ionized matter, as seen
by Nandra & Iwasawa (2007) in IRAS 00182-7112. The effect would be to increase
the soft X-ray flux compared to neutral reflection as the lighter elements
responsible for absorbing the soft X-rays will have been stripped of most of
their electrons. This would fit well with the soft spectrum seen in IRASF
01475-0740.
The case of IRASF 01745-0740 shows that Compton thick/intermediate AGN do not
have to be reflection dominated with intense iron lines as they can be
transmission dominated with a strong scattered component and no intense iron
lines.

3. 2003ApJS..148..327S
Re:IRAS 01475-0740
5.3. IRAS 01475-0740
This is a Seyfert 2 galaxy with strong radio emission (Schmitt et al.
2001b; Thean et al. 2000), unresolved on VLA scales, and also known
to have polarized broad emission lines (Tran 2001). The [O III]
emission (Fig. 5, middle left) has a halo-like morphology with an
average extent of 0.8" (275 pc).

4. 1995AJ....110...87H
Re:IRAS 01475-0740
01475-0740 (Fig. 1(f)]: This is among the strongest radio sources in
our sample, with a flat FIR-to-radio spectral index indicative of a
contribution by a nonthermal component. The radio emission is unresolved
at 6 and 20 cm (paper I) within a region which is similar to the size of
the featureless H{alpha} emission region.

5. 1994AJ....107...35H
Re:IRAS 01475-0740
01475-0740. Deep CCD frames and digitally enhanced frames show that
this amorphous, nearly round galaxy lacks any distinguishing features.
There are many faint patches surrounding this galaxy and we label them in
Fig. 16. We estimate that the errors associated with U-B and B-V colors
of these faint patches to be roughly +/-0.20 and +/-0.10, respectively.
The measured colors of these faint patches (Table 9) are too blue to be
typical globular clusters. If these faint objects are companions at the
same redshift as IRAS 01475, they are intrinsically faint (absolute
blue magnitudes fainter than -13), and cover a radius of only ~40 kpc,
making them unlikely candidates for companion dwarf galaxies. If, on the
other hand, we assume that they are normal galaxies with absolute blue
magnitudes of roughly -21 to -22, then their apparent magnitudes would
place them at a redshift of z~0.4, and they would cover a projected
radius of ~1 Mpc, which is the typical size of a group of galaxies. We
conclude that these faint patches surrounding IRAS 01475 have magnitudes
and colors that are consistent with them being a background group of
galaxies.


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