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Notes for object NGC 7469

42 note(s) found in NED.


1. 2009ApJ...705..962C
Re:NGC 7469
Several high-velocity Si III components are detected in this sight line at
negative velocity. Absorption in O VI associated with each of these components
is reported by S03. The strong highest velocity component is detected in a
variety of absorption lines ranging in ionization from O I to C IV. We break
this strong absorption feature into two components separated at V_LSR_ = -270 km
s^-1^. The lowest-velocity component is not detected in low ions, only in the
higher ions C IV, Si IV, and Si III.

2. 2008MNRAS.391.1009L
Re:NGC 7469
NGC 7649: the surface brightness profile was published by Schombert (1986) and
the HST imaging by Laine et al. (2003). A KDC is clearly visible in the centre
of this galaxy.

3. 2008A&A...484..341R
Re:NGC 7469
For this prototypical Seyfert 1 galaxy we encountered an unknown image quality
problem. Soifer et al. (2003) present a high resolution (4" x 4") 12.5 micron
image of the nucleus of NGC 7469, resolving the ring structure around the
nucleus and an extended structure in the nucleus itself.

4. 2007ApJ...671.1388D
Re:NGC 7469
A2.1. NGC 7469 Star formation on large scales in NGC 7469 has been studied by
Genzel et al. (1995). They found that within 800 pc of the nucleus, a region
that includes the circumnuclear ring, the luminosity from young stars was ~3 *
10^11^ L_sun_, about 70% of the galaxy's bolometric luminosity. This situation
is similar to that in Mrk 231. On smaller scales, the nuclear star formation in
NGC 7469 was directly resolved by Davies et al. (2004a) on a size scale of
0.15"-0.20" (50-65 pc) FWHM. An analysis of the long-slit data, similar to that
for Mrk 231, was made, making use of stellar absorption features, kinematics,
and starburst models. We estimated that the age of this region was no more than
60 Myr under the assumption that the fraction of stellar light in the K band in
the central 0.2" was 20%-30%. Our new integral field SINFONI observations of NGC
7469 at a spatial resolution of 0.15" (measured from both the broad Br{gamma}
and the nonstellar continuum profiles; see {section} 2) are used here to make a
more accurate estimate of the nuclear K-band luminosity. They enable us to
provide a short update to the detailed analysis in Davies et al. (2004a).
The SINFONI data show that the equivalent width of the 2.3 {mu}m
CO(2-0) is W_CO(2-0)_ = 1.8 A in a 0.8" aperture and 0.9 A in a 0.2" aperture.
The corresponding K-band magnitudes are K = 10.4 and 11.8, respectively. If one
takes the intrinsic equivalent width of the 2.3 {mu}m CO(2-0) band head to be 12
A (see {section} 3), one arrives at a more modest value of 8% for the stellar
fraction of K-band continuum in the 0.2" aperture. The stellar K-band luminosity
in this region is then 6 * 120^^7^L_sun_. Comparing this to the dynamical mass.
in Davies et al. (2004a) yields a mass-to-light ratio of M/L_K_ ~ 0.6
M_sun_L_sun_^-1^ Previously, extrapolation from a 37 mas slit to a filled
aperture had led to an underestimation of the total magnitude but an
overestimation of the stellar contribution. Fortuitously, these uncertainties
had compensated each other. The same analysis for the 0.8" aperture yields a
K-band stellar luminosity of 3 * 10^8^ L_sun_ and hence M/L_K_ ~ 1.6 M_sun_
:_sun_^-1^.

5. 2007ApJ...671.1388D
Re:NGC 7469
The K-band data cube yields estimates of the upper limit to W_Br{gamma}_ of
17 and 11 A in 0.2" and 0.8" apertures, respectively. This has been corrected
for dilution of the stellar continuum (as described in {section} 3) but not for
a possible contribution to the narrow Br{gamma} from the AGN. Hence, the actual
W_Br{gamma}_ corresponding to only the stellar line and continuum emission will
be less than these values, indicating that the star formation is unlikely still
to be ongoing.
We estimate the age of the star formation using the STARS models in
Figure 4. Within the 0.2" aperture this gives 100 Myr, comparable to our
original estimate. Such a young age is supported by radio continuum
measurements. With a 0.2" beam, Colina et al. (2001) reported that the
unresolved core flux in NGC 7469 was 12 mJy at 8.4 GHz. With much higher spatial
resolution of 0.03", Sadler et al. (1995) reported an upper limit to the
unresolved 8.4 GHz continuum of 7 mJy. We assume that the difference of 5 mJy is
due to emission extended on scales of 10-60 pc, which is resolved out of one
beam but not the other. As discussed in {section} 3, star formation is a likely
candidate for such emission. In this case, we would estimate the supernova rate
to be ~0.1 yr^-1^ and the ratio 10^10^{nu}SN/L_K_ ~ 3 . This is likely to be a
lower limit since there was only an upper limit on the core radio flux density.
For a ratio of this order, even allowing for some uncertainty, Figure 4 implies
an age consistent with no more than 100 Myr. Within the 0.8" aperture, which we
adopt in Table 3, continuous star formation is inconsistent with W_Br{gamma}_.
For a star formation timescale of t_SF_ = 100 Myr, the mass-to-light ratio
implies an age of 190 Myr, just consistent with the measured value of
W_Br{gamma} = 11 A. If some of the narrow Br{gamma} is associated with the AGN
rather than star formation, then a shorter star formation timescale is required.
For t_SF_ = 10 Myr, the ratio M/L_K_ yields an age of 110 Myr.

6. 2007AJ....134.1061D
Re:NGC 7469
NGC 7469 is a highly studied Seyfert 1 galaxy. Many surveys and studies to
date have classified this as an intrinsically absorbing Seyfert galaxy
(Scott et al. 2005; Kriss 2002; Crenshaw et al. 1999). Thus, this object
is a known intrinsic absorber. In the FUSE data, however, the absorption
appears very weakly, and in the Ly{beta} line there is a C II ISM line
along with two heavy H_2_ lines leaving doubt about the absorption^
feature. The O VI blue line is found at the same wavelength as Ar I
({lambda}1048 A), which tends to be a strong ISM line in the far-UV.

7. 2007AJ....134..648M
Re:NGC 7469
NGC 7469 (Figs. 7.14, 9.14, 20.14): This is very interesting object, with a
faint spiral that becomes a conspicuous ring of star formation in the inner few
hundred parsecs. Many stellar clusters are individually resolved within this
region.

8. 2007A&A...461.1209D
Re:NGC 7469
NGC 7469: The BeppoSAX data were already published by De Rosa et al.
(2002a). The X-ray spectrum of the source is well fit by a power law
plus a reflection component. An high energy cut-off is detected at
E ~ 210 keV. De Rosa et al. (2002a) found that the reflection could be
due to ionized matter. This is also indicated by the presence of a
narrow emission line due to ionized iron at E = 7.0 +/- 0.2 keV
(EW = 75 +/- 40 eV). The results presented here are in agrement with
those obtained by De Rosa et al. (2002a), although the ionized
reflection has not been tested here.

9. 2006ApJ...638..106W
Re:NGC 7469
This object is a luminous infrared source. Its circumnuclear (1.5"-2.5") ring
structure has been observed at radio, optical, near-infrared, and mid-infrared
bands (see references in Davies et al. 2004). Using the 2.3 micron CO 2-0
absorption and continuum slope, Davies et al. (2004) resolved the nuclear star
cluster (0.15" - 0.20") and found that the age of the cluster is less than about
60 Myr.

10. 2006A&A...457...61R
Re:NGC 7469
NGC 7469. This well-studied Seyfert 1 galaxy, is widely known because
the active nucleus is surrounded by a more or less complete ring of
powerful starburst activity (Mauder et al. 1994; Miles et al. 1994;
Genzel et al. 1995). The circumnuclear ring has a luminosity equivalent
to two-thirds of the bolometric luminosity of the entire galaxy. It
contains a number of supergiant star formation regions with a few 104
OB stars each. It has been studied in the NIR by several authors, among
them, Genzel et al. (1995), Thompson (1996), and Sosa-Brito et al.
(2001). The NIR spectrum of Genzel et al. (1995) display bright lines
of Br{gamma}, [Fe II], [Si VI], H2, He I, and CO on a scale of less
than a few hundred parsecs. The NIR spectrum shown in Fig. 7, to our
knowledge the first one that simultaneously covers the interval 0.8-2.4
microns, displays a wealth of emission lines, with He I 1.083 microns
and [S III] 9531 Angstrom as the strongest ones. High-ionization lines
of [S VIII], [S IX], [Si VI], and [Si X] wer e identified. The
continuum emission is steep, of a broken power-law type. Stellar
absorption features were detected mostly in the H- and K-bands. In the
latter, the 2.3 microns CO bandheads are prominent for a type 1 object.

11. 2005ApJ...633..105D
Re:NGC 7469
4.9. NGC 7469 - Our spectrum of NGC 7469 is similar to that of Sosa-Brito et
al. (2001), showing fairly deep absorption features, as well as both narrow and
broad Br{gamma}emission. Although this galaxy is considered to be a prototypical
Seyfert 1, much of the attention it has received is focused on the
circumnuclear ring on scales of ~1.5"-2.5", which is responsible for
about half of the galaxy's bolometric luminosity. In additional, about
one-third of the K-band continuum in the nucleus itself originates in star
formation (Mazzarella et al. 1994; Genzel et al. 1995; Davies et al. 2004a).
Comparing the luminosity profile of the 1-0 S(1) line with its dynamics at a
resolution of <0.1" (and also the dynamics of the cold molecular gas at
0.7" resolution), Davies et al. (2004a) concluded that the very central
peak in the 1-0 S(1) emission was not associated with the gas or star-forming
distributions and was most likely to originate in gas irradiated by X-rays from
the AGN. Unfortunately, in a 1" aperture, the 1-0 S(1) flux from this
component is expected to contribute only about 20%-25% of the total 1-0 S(1)
flux. It may not be possible-on seeing-limited scales-to resolve the more
extended dominant component, which is presumably excited by star formation,
from the nuclear point source.

12. 2004MNRAS.350.1087S
Re:NGC 7469
NGC 7469: a large excess for 2 <~r<~ 6 kpc is observed in all the surface
brightness profiles. Marquez & Moles (1994) attribute this feature to a
lens structure, although they did not perform an accurate numerical
fitting.

13. 2004MNRAS.350.1049G
Re:NGC 7469
9.27 NGC 7469 Oknyanskij & Horne (2001) have taken the data of Glass
(1998) and cross-correlated it with published and unpublished U
photometry (e.g. Doroshenko, Lyutyi & Rakhimov 1989; Chuvaev, Lyutyi &
Doroshenko 1990), finding that there are delays of 52 +- 15 d at K and
60 +- 10 d at L. The present data, using only the published U
photometry, yield, with lower significance, a delay between U and L of
~21 d and between J and L of ~40 d. The Oknyanskij & Horne (2001) value
should probably be preferred.

14. 2004ApJ...613..682P
Re:NGC 7469
NGC 7469. This object is one of a very few in which a lag has been
detected between the UV and optical continuum variations (Wanders et
al. 1997; Collier et al. 1998). We therefore in this case use the UV
continuum (at 1315{Angstrom}) as the driving continuum in the
cross-correlation analysis.

15. 2003ApJS..146..353M
Re:NGC 7469
NGC 7469 (TW)
The most noticeable feature of this galaxy is the bright circumnuclear
starburst ring, followed by the prominent Seyfert 1 nucleus. Outside
of the ring there is a tightly wound nuclear dust spiral, although it
is difficult to determine if this structure continues inside the ring.

16. 2003ApJS..146....1W
Re:NGC 7469
NGC 7469.-The strong high negative velocity HVC component is split in
two by the Galactic H_2_ J = 3 absorption, making the equivalent width
measurement difficult. However, some of the absorption near
-210 km s^-1^ is O VI, rather than H2. After removal of the H_2_ line,
the high-velocity component can be split in two components. This direction
lies within the tip of the H I Magellanic Stream, and there is H I at
-333 km s^-1^. Thus, some of the O VI HVC component at -305 km s^-1^ may
be associated with the Stream.
The systematic error on the equivalent width and column density of the
high negative velocity comppnents reflects the uncertainty in the H_2_
parameters. This increases the systematic errors from 9 to
21 m{angstrom} and from 17 to 40 m{angstrom} for the -305 and
-185 km s^-1^ O VI components, respectively.
Based on the strength of the H_2_ J = 0 and J = 1 lines (they have
damping wings, and N(H2) > 10^19^ cm^-2^), the HD line at 1031.912
{angstrom} may be present. At the wavelengths of the HD 3-0 R(0) through
8-0 R(0) lines at 1066.271, 1054.433, 1042.847, 1031.912, 1021.456, and
1011.457{angstrom} (Dabrowski & Herzberg 1976) features with equivalent
widths of 21 +- 8, 12 +- 6, 29 +- 11, 19 +- 7, 15 +- 7, and 15 +- 7
m{angstrom}, respectively, can be measured. It is therefore likely that
the sharp feature centered at 1031.912 {angstrom} is HD. This feature
was removed before calculating for the Galactic O VI parameters.
The sight line passes through the Pegasus Spur
(v = 1110 +- 260 km s^-1^) and the edge of the Pegasus Galaxy Grouping
(v = 2170 +- 480 km s^-1^). The absorption between -375 and -120 km s^-1^
cannot be intergalactic Ly{beta} since the corresponding Ly{alpha}
absorption is not seen in the FOS spectrum of NGC 7469. A strong
Ly{alpha} line is found at v = 3070 km s^-1^. The corresponding Ly{beta}
absorption mostly overlaps the low-velocity C {lambda}1036.337 line, and
it causes the sloped negative-velocity wing on that line.
C II absorption is seen at a velocity of -335 km s^-1^, with
W = 185 +- 10 m{angstrom}. An H I component with
N(H I) = 3.3 x 10^18^ cm^-2^ iS seen in the Effelsberg spectrum with
a FWHM of 27 km s^-1^. This is compatible with the CH absorption for
gas with Magellanic abundances.

17. 2002ApJS..143...47D
Re:IRAS 23007+0836
IRAS 23007+0836 (NGC 7469).---This is a well-known Seyfert 1 galaxy.
Broad Balmer lines were first observed in this galaxy by Seyfert
(1943), and confirmed in hundreds of subsequent studies. NGC 7469 is
known to contain circumnuclear starburst activity and is sometimes
classified as a composite object (e.g., Goldader et al. 1997b).
Numerous images of NGC 7469 have previously been obtained over a
large wavelength range (e.g., Nandra et al. 2000; Papadopoulos & Allen
2000; Kriss et al. 2000; Genzel et al. 1998; Kotilainen & Ward 1997).
From our images, the majority of the red continuum and H{alpha}
emission occurs in the nuclear regions. There are a number of
star-forming knots in the northern spiral arm, but none in the south.
Since NGC 7469 is known to be interacting with IC 5283, 1.4' away, it
is likely that this star formation has been induced by the interaction.
The red continuum image of IC 5283 shows a strong tidal tail to the
northeast, and a knot of diffuse emission to the north, neither of
which are visible in the H{alpha} image. The H{alpha} emission in IC
5283 is mostly concentrated along its disk, in multiple knots with the
eastern knot being the most luminous.

18. 2002AJ....124..675C
Re:UGC 12332
Seyfert 1.2.

19. 2002A&A...389..802P
Re:NGC 7469
NGC 7469. The BMS fit gives a marginally acceptable {chi}^2^ = 191/151,
but, like in the case of Mrk 509 as illustrated in Perola et al. (2000),
the line width is practically unconstrained (about 2 keV). The addition
of a soft excess in the form of a power law changes the situation
radically. The slope of the soft power law is {GAMMA}_s_ = 3.3 +/- 0.5,
its normalization 5.5x10^-3^ cm^-2^ s^-1^ keV^-1^ at 1 keV. N_s_ is
negligible compared to N_g_, and N_W_ =(6.7^+4.3^_-3.7_)x10^20^ cm^-2^
with X_i_ ~ 0.13 erg cm s^-1^. The line is not resolved, the upper
limit on its width is comparable to that of the lines resolved in our
sample. In a spectral variabilty study with RossiXTE, Nandra et al. (2000)
detected changes in the line intensity which are not correlated with
the absolute normalization of the reflection component, but they
themselves doubt the reliability of their estimate of the second of
the two parameters. We note that George et al. (1998) did not find
evidence of a soft excess in their analysis (above 0.6 keV) of a ASCA
observation with a flux 25% lower than in our data: thus the
additional soft component, that we suggest here to provide a better
description of the continuum of this observation, should be variable.
We further note that the value of {GAMMA} in Table 2 is in good
agreement with {GAMMA} = 1.92 +/- 0.02 obtained by Nandra et al. (2000)
from the integrated fit of the data in the study mentioned above, with
an average flux only 10% lower than in our observation.

20. 2001ApJS..136...61S
Re:NGC 7469
5.29. NGC 7469
NGC 7469 is often cited as the prototypical Seyfert 1 galaxy. A variety
of observations at high spatial resolution indicate that the active nucleus
is surrounded by a more or less complete ring of starburst activity
(Mauder et al. 1994; Genzel et al. 1995; Miles, Houck, & Hayward 1994;
Wilson et al. 1991). Genzel et al. (1995) have modeled their
high-resolution NIR imaging and imaging spectroscopic data and find that
two-thirds of the bolometric luminosity of the entire galaxy originates in
this starburst ring. Perez-Olea & Colina (1996) cannot spatially resolve
the starburst ring in their ROSAT HRI data but derive its X-ray luminosity
by using the results of the radio observations of Wilson et al. (1991)
together with the assumption that its L_X_/L_5 GHz_ ratio is typical of
starbursts (~400). They then arrive at the conclusion that only 4% of the
total X-ray luminosity is produced in the ring. The active nucleus itself
is seen to vary in the X-rays over timescales from hours (Barr 1986) to
days (Leighly et al. 1996). Doroshenko, Lyutyi, & Rakhimov (1989) report
on nuclear optical variations with timescales ranging from hours to years.
In the infrared, Glass (1998) found small (<0.3 mag) variations during the
course of 13 years of observations, except for a substantial dimming in
1989 during which the nuclear flux dropped to one-fifth its normal value.
Related decreases in the U and B brightnesses, along with the disappearance
of the broadline component of H are reported by Glass (1998) and references
therein.

21. 2001ApJ...550..261W
Re:NGC 7469
3.3.14. NGC 7469 (Mrk 1514)
Between the four ASCA pointings, the 2-10 keV flux varies by as much as
50% (Fig. 8n). The line energy changes, but the errors on line flux and EW
are too large to comment more on the variability of these parameters. In a
month-long RXTE monitoring campaign, the line flux was found to be well
correlated with the 2-10 keV continuum flux, with evidence that the
line-emitting region lies within a few light-days of the continuum source
(Nandra et al. 2000).

22. 2000ApJS..131..413Z
Re:NGC 7469
5.2.15. NGC 7469
NGC 7469 is a bright, luminous, and well-observed SBa galaxy with a
Seyfert 1 core (Genzel et al. 1995; Cutri et al. 1984). The companion
IC 5283 is about ~80" to the north. NGC 7469 has an optical size of
100" x 60" (Nilson 1973), but our DSS frame shows only the core with a size
of ~40" x 20" (Fig. 16). Near-IR profiles show a sharply peaked
distribution with scale size of ~2" (Zenner & Lenzen 1993) or less
(Terndrup et al. 1994; Mazzarella et al. 1994; Genzel et al. 1995). There
is 1.5 x 10^10^ M_sun_ of H_2_ concentrated in the central 2" of NGC 7469
as determined by studies of CO emission (Meixner et al. 1990) and somewhat
less of H I (Mirabel & Sanders 1988). Some of this gas is concentrated in
a clumpy nuclear ring of radius ~1.5" seen in radio (Wilson et al. 1991;
CHYT), visible light (Mauder et al. 1994), and even at 11.7 microns (Miles,
Houck, & Hayward 1994). In addition, NGC 7469 shows emission lines from
polycyclic aromatic hydrocarbons (PAHs) from the extranuclear region
(Miles et al. 1994; Mazzarella et al. 1994; Cutri et al. 1984).
Miles et al. (1994) point out that these molecules would be destroyed by
the X-ray flux from the active core of NGC 7469 and note that shielding by
clumps of gas with N_H_ > 10^23^ atoms cm^-2^ could protect them.
Despite the assertion that the majority of the log(L_FIR_/L_sun_) = 11.2
is concentrated within the circumnuclear ring with a ~2" diameter
(Genzel et al. 1995), a very small fraction of 100 micron flux may be seen
on a considerably larger scale (Fig. 16). Our fitting and deconvolution on
this high S/N object allows some superresolution and gives D_g_ = 14" and
D_e_ = 7". While the majority of the FIR flux lies on scales well below our
resolution, there may be some flux extended beyond the circumnuclear ring.
Photometrically, the IRAS flux is recovered exactly, within our
uncertainties, so it is not possible to use the flux deficit to estimate
the size.
With our estimate of D_e_ = 7", the single-slab model for the dust gives
{tau}_100_ > 5 x 10^-2^, which converts to an A_V_ > 35. This extinction
cannot surround the AGN since it is easily visible in the optical. Using
N_H_/A_V_ = 1.9 x 10^25^ (Bohlin, Savage, & Drake 1978), the column density
is N_H_ > 6.7 x 10^22^, which is high enough to adequately shield the PAHs
(Miles et al. 1994).
The flux obtained for NGC 7469 used only detectors 1-9 for both the
baseline and the flux by summation of detectors. This was done because of
the excess flux seen by detector 10, which is close to IC 5283. While the
IRAS position does not appear to be biased by this companion and the IRAS
flux was recovered in detectors that excluded it, the data are suggestive
that IC 5283 contributes modestly to the luminosity of the system. These
two galaxies were resolved separately at 12 and 25 microns with HIRES
studies on the IRAS database (Surace et al. 1993). In this study, IC 5283
was found to be less than 5% of NGC 7469 at 25 microns - a ratio that is
surprisingly small given the conspicuousness of the former in our data set,
in which it is probably only partly sampled. It would appear that IC 5283
has a cooler spectrum than NGC 7469.
Optical studies of this pair (Marquez & Moles 1994) show that IC 5283
is, in itself, a strongly disturbed system. There appears to be little
evidence for a substantial stellar or gaseous component bridging the
systems, and the lack of 100 micron emission between them (in our detectors
7-9) is therefore not surprising.

23. 2000AJ....119..991S
Re:NGC 7469
The near-infrared emission from NGC 7469 is dominated by the
bright, pointlike Seyfert nucleus point source. However, the bright
inner disk of the galaxy has been seen in much earlier optical
(De Robertis & Pogge 1986; Wilson et al. 1986) and near-infrared
(Mazzerella et al. 1994) imaging and is discussed extensively in Genzel
et al. (1995). A short spiral armlike feature in the northwest is
clearly seen in the point-source subtracted images (Fig. 3). (The bright
linear south southeast-north northwest feature is a PSF artifact that we
were unable to remove in the 2.2 micron image.) In the inner disk, there
is a ring of star formation at ~1" radius, corresponding to 500 pc. The
structure within the ring is similar in all three bands and is well
outside the area in which residual PSF should introduce structure. This
starburst disk is very similar to that seen in NGC 1068; in NGC 7469
there is no evidence of a bar like that seen in NGC 1068. The secondary
companion to NGC 7469, IC 5283, is 80" (26 kpc) away and therefore well
outside the field of our images. The data for this galaxy will be
discussed more thoroughly in Thompson et al. (2000).

24. 1998ApJS..114...73G
Re:NGC 7469
Section A17. NGC 7469
This Seyfert 1.2 galaxy was first detected in X-rays by Uhuru (Forman et al.
1978) and observed by ASCA on three occasions over a period of ~9 days in
1993 November. However, only one observation [NGC 7469(2)] met the criteria
for inclusion in our sample (Paper I). We find a simple power law [model A(i)
with {GAMMA} ~ 2.0] provides an acceptable description of the spectrum.
However, there is evidence for some spectral curvature, which leads to a
significant improvement in the goodness of fit for models A(ii), B(ii), and
C(ii) if the bulk of continuum is unattenuated (D_f_ >~ 0.6), while the
remainder is absorbed by a large column density (N_H, z_ >~ few x 10^23^
cm^-2^), or if there is a strong (F ~ 7) Compton-reflection component
(Section 6.4.1).
.
Guainazzi et al. (1994) have presented a combined analysis of the
NGC 7469(1,2) data sets. They found a ~40% decrease in intensity between the
two epochs, with some evidence for a steeper spectrum in the soft X-ray band
(<~0.8 keV) when the source is brighter. No such spectral variability was
seen >~2 keV, with both epochs consistent with a power law with {GAMMA} ~
1.9. We see no reliable evidence for a soft excess in our analysis of the
NGC 7469(2) data set; however, we note that the results of Guainazzi et al.
(their Fig. 3) indicate such a component would be almost indistinguishable at
that epoch. Spectral complexity in NGC 7469 <~1 keV has been suggested by
previous Einstein, EXOSAT, and ROSAT observations although its form remains
illusive (see, e.g., Brandt et al. 1993; Leighly et al. 1996a and references
therein). We note some soft flux is provided in our models that include
emission, but generally this is small (except in the case of our model
including a Compton-reflection component).
.
In their analysis of the mean spectra from the NGC 7469(1,2) data sets,
Guainazzi et al. find the putative soft excess to be consistent with a
blackbody with kT ~ 0.08 keV. Guainazzi et al. find no evidence for O VII
and/or O VIII absorption edges, while R97 find the addition of an O VII edge
(of optical depth {tau}_O7_ ~ 0.2) significantly improved the fit to a
single-power-law model ({GAMMA} ~ 2.1) to the NGC 7469(1) data set.
.
In Section 6.4.1, we found that a strong Compton-reflection component is
allowed by the data. Such a result is also obtained from previous HEAO 1
(W95) and Ginga (NP94; Leighly et al. 1996a) observations.
.
Finally, we note that NGC 7469 has recently been the subject of an intense
monitoring campaign in the optical, UV, and X-ray bands. Most interestingly,
preliminary results from the RossiXTE observations reveal the X-rays to have
exhibited large-amplitude variability apparently uncorrelated with the
variations seen in the UV and optical (Nandra et al. 1998a).

25. 1997MNRAS.286..513R
Re:NGC 7469
7.1.13 NGC 7469
These ASCA data on the Seyfert 1 galaxy NGC 7496 have been previously presented
by Guainazzi et al. (1994). They found a weak (W_Fe_~120 eV) narrow neutral
iron emission line. The present work (which benefits from recently improved
high-energy calibration) also finds a very strong (W_Fe_~1 keV) and very broad
({sigma}~1.2 keV) emission feature at these energies, although the narrow line
can still be seen in the residuals of the best-fitting model B. The
relativistic accretion disc emission-line model has difficulties explaining
such a spectral feature. A full discussion of this will be presented in a
future publication.

26. 1997ApJS..110..299M
Re:NGC 7469
The central few arcseconds of the K_S_image are elongated as in a bar,
however stars in the image show a similar elongation. There is no
evidence for a bar in the ellipse fits. Unbarred in the RSA.

27. 1997ApJS..108..449G
Re:NGC 7469
This Seyfert 1 galaxy appears to show variability at 2.2 microns (Nelson,
Malkan, & McLean 1994). NGC 7469 contains both a starburst and an AGN and
has intermediate spectral properties, as is seen in our analysis.

28. 1997ApJS..108..155G
Re:NGC 7469
This is a well-studied S1 galaxy; it is in an Sa host galaxy in
interaction with the irregular galaxy IC 5283 (Marquez & Moles 1994). The
nuclear region shows emission extending 14", surrounded by resolved H II
regions located at less than 2 kpc from the nucleus, showing a crab-
shaped appearance (Fig. 11e). The disk also shows H II regions. Optical
long-slit spectroscopic observations presented by Wilson et al. (1986)
indicate that the circumnuclear region is composed of two components, a
high-excitation gas ionized by the nucleus and a low-excitation gas
photoionized by hot stars. High-resolution radio continuum maps reveal
that most of the emission occurs in a ring of diameter 1 kpc centered on
the Seyfert nucleus, which is due to star formation (Wilson et al. 1991).
A Hubble Space Telescope (HST) image also shows the circumnuclear region
resolved in a complex of star-forming sites. Strong molecular gas within
a 2.5 kpc radius of the nucleus is detected by Meixner et al. (1990).
Other evidence of the circumnuclear starburst comes from the detection of
H_2_ {lambda}2.212 microns (Heckman et al. 1986).

29. 1997A&A...327..493R
Re:NGC 7469
NGC 7469 was observed in HI by Heckman et al. (1978). A prominent deep minimum
is seen in the HI profile. However, the possibility that this minimum is an
absorption feature was ruled out on the basis of the evidence that this
absorption feature was equally prominent in the direction of IC 5283 which is a
companion to NGC 7469. On the assumption of the validity of the previous claim
the first main peak on the HI profile is similar to the CO profile measured
here. The HI FWZI is 885 km/s, similar to the CO FWZI of 900 km/sec, while the
similarity in the shapes of the line profiles imply that CO and HI are well
mixed in the galaxy.

30. 1996ApJS..105...93E
Re:NGC 7469
4.17. NGC 7469
This early-type Seyfert 1 galaxy has been investigated in detail from X-ray
(Brandt et al. 1993) and UV (Westin 1984) wave bands through to medium-IR
wavelengths (e.g., Rudy et al. 1982; Keto et al. 1992; Miles, Houck, & Hayward
1994). Long-slit spectra and CCD imaging of the nuclear and immediately
surrounding regions (de Robertis & Pogge 1986) show evidence for ongoing star
formation in the circumnuclear ring. This may be driven by cloud-cloud
collisions due to the outflow of material from the nucleus (Westin 1985).
Additional optical emission-line and continuum images, and radio continuum
data, of the nuclear regions are published by Wilson et al. (1991), and Mauder
et al. (1994) present speckle masking images of the inner nuclear region.
Additional long-slit spectra have been obtained by Wilson et al. (1986) and
Bonatto & Pastoriza (1990). The latter authors conclude that the elemental
abundances at ~8" from the nucleus are approximately solar, with the exception
of nitrogen, which appears to be enhanced by a factor of 2 over the solar
value. Compact H II regions overlaying a diffuse H{alpha} background are
clearly visible within ~10" of the nucleus in Figure 1. Further out, a few
giant extragalactic H II regions are evident and appear to trace the weak
spiral arm structure out to a distance of order 50" from the nucleus.

31. 1996ApJS..104..217S
Re:UGC 12332
3.19. UGC 12332
UGC 12332 = NGC 7469 has a Seyfert 1 nucleus and star formation spread
throughout the disk. Nilson (1973) notes the presence of IC 5283, a compact
companion, at a separation of 1.4' (26 kpc). Both galaxies lie on the outskirts
of the Pegasus I cluster. A circumnuclear starburst ring with a diameter of 3"
has been imaged at 6 cm and 10 microns (Wilsonetal. 1991; Miles, Houck, &
Hayward 1994). Genzel et al. (1995) have obtained high-resolution near-infrared
images and spectra of the starburst ring. These authors conclude that the
circumnuclear starburst produces two-thirds of the bolometric luminosity of
this object. Although our images do not have sufficient spatial resolution to
resolve the nuclear structures observed by Genzel et al. (1995), our
measurements are consistent with their integrated fluxes. UGC 12332 has been
classified as a compact starburst by Condon et al. (1991b).

32. 1996ApJ...465..191M
Re:NGC 7469
3.8. NGC 7469
The deconvolved image of NGC 7469 in Figure 14 shows an unresolved nuclear
component surrounded by a lumpy ring, approximately 1 kpc (3") in diameter. The
two brightest features in the ring are on opposing sides of the nucleus, at
position angles of 40^deg^ and 205^deg^.
Correspondence between the infrared, optical, and radio is excellent. Detailed
comparisons of the radio image by Wilson et al. (1991) and our infrared image
have been previously published, along with results of spatially resolved,
low-resolution spectroscopy of the 11.3 micron PAH feature, which was shown to
arise in the circumnuclear region (Miles, Houck, & Hayward 1994). In the
optical, Marquez & Moles (1994) found an asymmetric optical light distribution
and peculiar rotation curve; Mauder et al. (1994) found the same lumpy ring
surrounding the unresolved nucleus using speckle interferometry. Gel et al.
(1995) found similar detailed structures in their near-infrared images. All of
these workers have concluded that the ring is composed of very active star
formation.
NGC 7469 is strongly interacting with IC 5283, located ~77" (24 kpe) to the
north-northeast (Dahari 1985).

33. 1996A&AS..115..439E
Re:NGC 7469
NGC 7469 is a Seyfert 1 SAB galaxy in pair with IC 5283. It has a partial
circumnuclear radio and optical ring showing starburst activity (Wilson et al.
1991). It has been observed with ROSAT (Brandt et al. 1993).

34. 1996A&AS..115..439E
Re:NGC 7469
NGC 7469 is a Seyfert 1 galaxy with extended IR emission (Surace et al. 1993),
forming a pair with IC 5283. It has significant radio and X-ray emission and
shows signs of violent star formation (Ulvestad et al. 1981; Condon et al.
1991; Fabbiano et al. 1992). It has a strong central CO emission source which
is extended along the major axis.

35. 1995MNRAS.276.1262K
Re:NGC 7469
NGC 7469: Type 1. Host galaxy: SBa (UGC). Radio: the bright C-array
component is slightly resolved. The A-array map shows a point source
surrounded by faint emission, but the large flux density discrepancy
between this and the C-array map indicates that ~30 mJy of extended flux
has been resolved. At 6 cm the object appears as a point source
surrounded by a halo of emission 2 kpc in extent (Condon et al. 1982).

36. 1995ApJ...447..121W
Re:NGC 7469
NGC 7469.-We confirm the spectral flattening observed by Ginga. Piro et
al. (1990) find the Ginga data can be described either by reflection,
having a ratio of the reflected to the direct component of 1.23 +/- 0.34,
or by partial covering with f_c_ ~ 0.3 and N_H_ ~ 1.5 x 10^24^ cm^-2^.
The upper limit on N_HFe_ is consistent with the Ginga upper limit
(NP94).

37. 1993ApJ...412..535W
Re:NGC 7469
NGC 7469.-The 10 micron position of this well-known Seyfert galaxy
coincides to within 1" with the visible peak and to within 2" with the
radio position published by Condon et al. (1990). Although the
compactness is close to unity for this source, the multiaperture
measurements (Fig. 1) indicate that at least some of the 10 micron
emission comes from a region beyond a radius of order 1" (300 pc). As
described by Wilson et al. (1991), the Seyfert nucleus of NGC 7469 is
surrounded by a starburst ring with a radius of about 1 kpc.

38. 1991ApJ...381...85T
Re:NGC 7469
Both SSS+MPC and IPC+MPC observations of NGC 7469 revealed the presence of a
soft excess component, consistent with the EXOSAT observations (Barr 1986).

39. 1976RC2...C...0000d
Re:NGC 7469
= Arp 298
= Holm 803a
= Kara[72] 575a
Non-interacting pair with IC 5283 at 1.3 arcmin north-following.
Type 1 Seyfert nucleus.
B(nucleus) = 14.7-15.5.
B_T(excluding nucleus) = 12.80.
Photograph:
Publ. Dept. A. Univ. Texas, II, 2, No. 7, 1968.
Photometry (Nucleus and Total Magnitude)
A.J., 73, 858, 1968.
Publ. Dept. Astr. Univ. Texas, II, 2, No 7, 1968.
Atti. Conv. Sci. Osserv. Cima Ekar, Padova-Asiago, 101, 1973
= Contr. Asiago No. 300bis.
Photometry (UBV):
Ap. J. (Letters), 150, L177, 1967.
Astrophys. Lett, 1, 171, 1968.
Sov. A.J., 16, 763, 1973.
Sov. A.J., 17, 169, 1973.
M.N.R.A.S., 152, 759, 1971.
M.N.R.A.S., 169, 357, 1974.
Photometry (I.R.: 1-21 microns):
A.J., 73, 870, 1968.
Ap. J. (Letters), 159, L165, 1970.
Ap. J. (Letters), 176, L95, 1972.
M.N.R.A.S., 169, 357, 1974.
Spectrum:
Ap. J. (Letters), 171, L37, 1972.
Ap. J., 182, 369, 1973.
Ap. J., 192, 581, 1974.
Internal Motions:
Ap. J. (Letters), 171, L37, 1972.
Ap. J., 182, 369, 1973.
Spectrophotometry:
Ap. J. (Letters), 154, L53, 1968.
Ap. J., 162, 743, 1970.
Ap. J., 164, 1, 1971.
Astr. Ap., 27, 433, 1973.
Astr. Ap., 33, 331, 1974.
Astr. Ap., 33, 337, 1974.
Sov. A.J., 11, 767, 1967.
Ast. Tsirk. No. 467, 1968.
M.N.R.A.S., 168, 109, 1974.
IAU Symp. No. 28, 83, 1968.
"Nuclei of Galaxies", 151, 1971.
Polarization:
Ap. J., 151, 71, 1968.
Astrofizika, 4, 409, 1968.
Astrofizika, 7, 417, 1971.
Astrofizika, 8, 509, 1972.
Ast. Tsirk. No. 454, 1967.
Rotation Curve and Mass Determination (in nucleus):
Ap. J., 182, 369, 1973.
Radio Observations:
Australian J. Phys., 19, 565, 1966.
A.J., 73, 876, 1968.
Astr. Ap., 33, 351, 1974.

40. 1973UGC...C...0000N
Re:UGC 12332
Arp 298
{(R')}SAB(rs)a (de Vaucouleurs)
Paired with 23 00.8 +08 36 = IC 5283 at 1.4, 25, 0.7 x 0.25, distorted
spiral, v = 4875, v(0) = 5083, m=15.2
In Arp's class "double galaxies with wind effects"; "absorption, knots. Note
apparent re-entrant spiral arm on south galaxy [UGC 12332]" (Arp)
{UGC incorrectly notes "Pec". H. Corwin}

41. 1964RC1...C...0000d
Re:NGC 7469
= Holm 803a
Extremely bright nucleus. Pseudo (r): 0.35 arcmin x 0.22 arcmin. Faint outer
whorls form pseudo (R): 1.2 arcmin x 0.85 arcmin. Isolated, detached arms.
Non-interacting pair with IC 5283 at 1.3 arcmin north-following = Holm 803b?
with {Delta}(RA) and {Delta}(Dec) of opposite sign.
Heidelberg Veroff. Vol. 9, 1926 and Lund 6 dimensions are for the bright
part only.
Photograph:
Ap. J., 137, 1023, 1963.
Spectrum: (Broad emission lines in the nucleus)
Ap. J., 97, 28, 1943.
Rotation and Mass:
Ap. J., 137, 1023, 1963.

42. 1956AJ.....61...97H
Re:NGC 7469
HMS Note No. 214
This spiral has a bright, semi-stellar nucleus whose spectrum
shows broad emission bands on an early-type continuum.
It has been studied spectrophotometrically
by Seyfert, C.K. (1943, Ap. J., 97, 28)


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