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Notes for object NGC 4698

15 note(s) found in NED.


1. 2012ApJ...754...67F
Re:NGC 4698
NGC 4698 .SAS2..-HST F606W shows some weak dust lanes in the central region
which do not, however, imply any sense of rotation. It is classified as a
classical bulge by Fisher & Drory (2010). Falcon-Barroso et al. (2006) find that
the stellar velocity field displays rotation perpendicular to the major axis
within the central ~= +/- 5". The major axis rotational velocity is very slowly
rising indicative of counter-rotation. The velocity dispersion profile is mostly
flat within the bulge region (r_b_ = 10.7") with a weak central peak. In the
small radial range that our data cover the h_3_ and h_4_ moments are mostly
compatible with zero.

2. 2006MNRAS.369..529F
Re:NGC 4698
NGC 4698 is a low-luminosity Seyfert 2 galaxy (Ho et al. 1995) that is thought
to have experienced a major or intermediate-mass merger (Bertola et al. 1999,
but see also Sarzi et al. 2000). The SAURON stellar velocity field displays
regular rotation around the minor axis. The inner parts, however (i.e. 5
arcsec), appear to be rotating perpendicularly to the main body of the galaxy,
consistent with a nuclear disc in our unsharp-masked image (see also Pizzella et
al. 2002). We note, however, that no clear evidence for such decoupled inner
component is found in either the velocity dispersion or h_3_ maps. This result
is consistent with long-slit results from Bertola et al. (1999). The ionized-gas
distribution is rather regular, with H{beta} being more extended than [O III].
The velocity fields of the ionized-gas are consistent with that of the stars.
Koopmann & Kenney (2004), from H{alpha} observations, reported a low level of
star formation across the disc.

3. 2006A&A...460...45G
Re:NGC 4698
NGC 4698 (UGC 7970). This galaxy shows very faint, high-energy X-ray emission
from its central region. The largest extension is found at intermediate
energies, between 1 and 4 keV (Fig. 5). Georgantopoulos & Zezas (2003) make a
careful analysis of the Chandra data on this source and find that the X-ray
nuclear position coincides with the faint radio source reported by Ho and
Ulvestad (2001). They find that the best-fit model consists of an absorbed power
law with {GAMMA} = 2.18 and column density of N_H_ = 5 x 10^^20^ cm^-2^,
which gives a nuclear luminosity of 10^39^ erg s^-1^.
We found from the color-color diagrams that the data are consistent with a
combined model of a power law with {GAMMA} = [1.2-1.6] and a thermal component
with kT = [0.7-0.8] keV and a luminosity lower by a factor of two than the
one estimated by Georgantatopoulos & Zezas (2003). Cappi et al. (2006) fit
its XMM-Newton spectrum with a single power law model with {GAMMA} = 2.0
and get L(2-10 keV) = 1.6 x 10^39^ erg s-^1^, a factor of 3 brighter than
our determination.

4. 2004MNRAS.355.1251L
Re:NGC 4698
NGC 1084, 4698, 4962, 5962 and 6753. There are some non-barred galaxies
in the sample whose decompositions were improved by modelling ovals by
a Ferrers function. As an example the decomposition for NGC 6753 is
shown in Fig. 2(b) (see the online version). In this case, the oval has
a relatively low surface brightness and cannot be directly
distinguished in the profile. However, it is prominent in direct images
and divides the zone between bright nuclear and outer rings (see
Crocker et al. 1996).
The decomposition remained unsatisfactory for the galaxies NGC 4487,
4900, 2139 and 4618. Characteristic for all these galaxies is that they
have little or no bulge, or that the bulge has very low surface
brightness in comparison with that of the disc. As an example, the
decomposition of NGC 4487 is shown in Fig. 2(b) (the online version).
For this galaxy, the bulge model has a very large shape parameter (n =
5), which appears immediately after giving the initial parameters of
the fit. Such a centrally peaked extended bulge is the only solution
for this galaxy, but it is not clear whether the solution is physically
reasonable. At least it is not intuitively expected in the profile,
where the bulge does not look very prominent. Among the sample galaxies
there is also one galaxy, NGC 4900, having a strong Freeman type II
profile, which makes it impossible to fit any usual global disc model,
unless a truncated disc is assumed. In this study, the radial
scalelength of the disc for this galaxy was estimated from the outer
regions of the disc, whereas the bulge model was extracted using the
inner portions of the image. The decomposition was uncertain also for
the two late-type spirals, NGC 2139 and 4618, both having an asymmetric
disc. NGC 4618 is a prototypical one-armed SBm spiral (de Vaucouleurs &
Freeman 1972) and most probably has no bulge at all.

5. 2004A&A...418..877A
Re:NGC 4698
NGC 4698: the central galaxy here is a bright nearby Seyfert 2
galaxy. Foschini et al. (2002c) identified a ULX within only 73 arcsec
of the nucleus of the galaxy. If it was an object at the same distance
as the galaxy it would have a luminosity of log L_X_ = 39.5 erg
s^-1^. This ULX, however, turned out to be a quasar of z= 0.43. In fact
it turned out to be a pure absorption line BL Lac quasar which is a very
rare type of object. Its apparent magnitude was quite red, B = 21.3 and
R =19.6 mag. In order to get it roughly on the V system we take a mean
of these and get an absolute magnitude of M_abs = -10.4 mag,
corresponding roughly to the lower limit of the optical luminosities of
the ULX/quasars in Table 1.
Note: It is perhaps significant that almost exactly on a line through
the nucleus of NGC 4698, extended beyond the BL Lac, is another,
stronger X-ray source, 1RXS J124828.2+083103. It has a redshift of
z = 0.120. Extended further beyond that is a line of fainter galaxies of
unknown redshift (Forschini et al. 2002c). It is very similar to the
lines of galaxies extending from active low redshift galaxies that were
found in (Arp 2001).

6. 2002ApJS..143...73E
Re:NGC 4698
NGC 4698.---S(r)a: System seen close to edge-on. Bright nuclear point
source embedded in a large, luminous bulge. Bulge isophotes are
circular. A smooth disk surrounds the bulge. There are no signs of
star formation, but there are features in the disk that could be
either very tightly wrapped spiral arms or a ring.

7. 2002A&A...392..817F
Re:NGC 4698
3.10 NGC 4698
We find one ULX with sufficient statistics to perform spectral fitting. The
best fit is a power law with {GAMMA} = 2.0 +/- 0.2 ({chi^2^=18.3, {nu} = 24)
that gives a flux of 8.6 x 10^-14^ erg cm^-2^ s^-1^ and a luminosity of
3x10^39^ erg s^-1^.
Other statistically acceptable models are BB with kT = 0.35 +/- 0.05 keV
({chi^2^=34.5, {nu} = 24), BR with kT = 2 +/- 1 keV ({chi^2^=19.0, {nu} = 24),
and MCD with kT = 0.6 +/- 0.1 keV ({chi^2^=23.7, {nu} = 24).

8. 2002A&A...388...50F
Re:NGC 4698
This Sa galaxy shows a remarkable orthogonal geometrical and
kinematical decoupling between the inner portion of the bulge
and galaxy disk (Bertola et al. 1999). The asymmetric shapes
of the H{alpha} and [N II] lines are seen at a simple visual
inspection of the spectrum, and they are more evident in the
PV diagram obtained from the [N II]{lambda}6583 line. Although
we measured an increase of the velocity gradient toward the
center, we note that NGC 4698 has the shallowest outer gradient
of all the sample galaxies
({DELTA}V/{DELTA}r)_out_ =0.05 km s^-1^pc^-1^). This gradient
corresponds to the central plateau measured in the ionized-gas
rotation curve by Bertola & Corsini (2000). The Type III
classification has been assigned to this PVdiagram on the basis
of its high central-to-outer integrated-flux ratio.

9. 2001ApJS..133...77H
Re:NGC 4698
NGC 4698 (S2). - This galaxy was marginally detected at 6 cm but not at
20 cm. Hummel et al. (1987) obtained a less stringent upper limit of
S_20_ < 1.5 mJy ({DELTA}{theta} = 1.3").

10. 1997ApJS..112..391H
Re:NGC 4698
NGC 4698.--The emission lines of this low-luminosity Seyfert nucleus are quite
narrow (FWHM~170 km s^-1^), despite the fairly early Hubble type (Sa) of the
host galaxy. No trace of broad H{alpha} is visible in the relatively high S/N
spectrum (Fig. 13f).

11. 1994CAG1..B...0000S
Re:NGC 4698
Sa
(E/I,I,1/2)
CD-1881-HB
April 11/12, 1981
103aD + GG495
45 min
The print of NGC 4698 here shows the
E-like bulge in which there is no evidence of
recent star formation or spiral structure. This is
in contrast to NGC 4699, at the right, where the
MAS pattern can be traced on the original plate
into the bulge almost to the center.
The low-surface-brightness disk is enhanced
in the negative print. It is also well seen in the
positive print on the next page and in the Sa
summary, panel 87.
The spiral arms become prominent only in
the outer part of the disk. They are defined
primarily by the dust which forms fragmentary
lanes of the multiple-armed (MAS) type rather
than of the grand design. The silhouette of the
several dust lanes against the bulge is well seen in
the high-contrast print here, and on the next
page and on the Sa summary panel.
Because of (1) the smooth inner disk, (2) the
large bulge with no recent star formation, and (3)
the tightly wound spiral arms, this galaxy is in the
earliest one-third of the Sa morphological box,
earlier than the other galaxies on this page. The
progression along the MAS subset of the Sa
section is shown both here and in the Sa summary,
panel 87.

12. 1994CAG1..B...0000S
Re:NGC 4698
Sa
(E/I,I,1/2)
CD-1881-HB
April 11/12, 1981
103aD + GG495
45 min
The nuclear bulge dominates the central
region of NGC 4698 on the print here. The dust
in the tightly wound spiral arms is seen well in
silhouette against the large bulge. The galaxy is
shown again in a negative print in the Sa
summary, panel 86, where its relative place in the Sa
section is described, It is an early-to-intermediate
Sa, in about the first third of the Sa
classification box.

13. 1994CAG1..B...0000S
Re:NGC 4698
Sa
(E/I,I,1/2)
CD-1881-HB
April 11/12, 1981
103aD + GG495
45 min
The dust lanes and the multiple, luminous,
tightly wound arms are considerably more
developed in NGC 4698 than in NGC 1617,
above. The large central bulge dominates the
structure at this viewing angle. The spiral arms
in the outer part of the disk, seen best in the
positive print on panel 79, are still-subtler than
in the two galaxies in the right-hand columns,
where, especially in NGC 2775, the arms are
robust albeit fainter than in Sb and Sc galaxies
where the current star-formation rate is higher.

14. 1973UGC...C...0000N
Re:UGC 07970
SA(s)ab (de Vaucouleurs), Sa (Holmberg)

15. 1964RC1...C...0000d
Re:NGC 4698
Very bright diffuse nucleus in a bulge. Smooth inner region. 2 main, smooth
arms with a strong dark lane on one side. Similar to NGC 4594.
One aberrant value of (B-V) (source C) rejected.


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