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Notes for object NGC 2992

35 note(s) found in NED.


1. 2009ApJ...702.1127R
Re:NGC 2992
This galaxy is optically classified as a Sy1.9 nucleus, based on early published
spectra (Ward et al. 1980), which showed a weak broad H{alpha} component, but no
broad H{beta}. In a later observation (Allen et al. 1999), the broad component
of H{alpha} disappeared, leading to a new classification of the galaxy as a Sy2.
Gilli et al. (2000) reported that the spectrum regained the broad wings of
H{alpha} coinciding with a period of intense X-ray activity, contrary to the low
stage that was taking place during Allen's observations. Trippe et al. (2008)
report the re-classification of NGC 2992 as a Sy2 nucleus again, as of 2006. The
near-IR ground-based data were taken in 1998 April, coinciding with the epoch of
Gilli's observations, and thus with the classification as intermediate-type
Seyfert. On the other hand, our mid-IR measurements from Michelle were obtained
in 2006 May, coinciding with the Sy2 state. Thus, our IR SED includes fluxes
taken during different periods of activity of NGC 2992. This can explain its
similarity with a typical Sy2 SED. The clumpy models that include only torus
emission (and no direct AGN component) fit the observed data well. The
probability distributions are Gaussians for {sigma}, N_0_, and {tau}_V_, with
median values {sigma} = 45^deg^ +/- ^18^_21_, N_0_ = 7 +/- ^5^_3_, and {tau}_V_
= 36+/-^14^_11_. High values of i (>53^deg^) and low values of q (<1.0) are
preferred. The calculated optical extinction due to the torus is A_V_ < 160 mag.
NGC 2992 is the only intermediate-type Seyfert with the 10 {mu}m silicate
feature in absorption in the fitted models ({tau}^app^_10 {mu}m_ = 0.74). The
derived apparent optical extinction from the measurement of the band is
A^app^_V_ ~ 19 mag. The hydrogen column density along the LOS results in
N^LOS^_H_ = 2.5 * 10^23^ cm^-2^. This value results unrealistic when compared
with that inferred from X-ray measurements (N^X-rays^_H_ = 8 * 10^21^ cm^-2^).
This could be due to the intrinsic X-ray variability observed in NGC 2992
(Trippe et al. 2008).

2. 2008ApJ...678..102A
Re:SWIFT J0945.9-1421
An XRT observation of 11 ks took place on 2006 July 8. The only source detected
inside the BAT error box is located at R. A. (J2000.0) = 09^h^ 45^m^ 42.0^s^,
decl. (J2000.0) = -14^deg^ 19' 33.7". The source is coincident with the Seyfert
1.9 galaxy NGC 2992 and is 1.5' distant from the BAT detection. The source was
already detected in soft X-rays by ROSAT as 1RXS J094541.9-141927.

3. 2008ApJ...673...96A
Re:NGC 2992
NGC 2992 is a Seyfert 1.9. The best fit for combined XRT, ASCA, and BAT data is
an absorbed power law with a photon index of 1.24^+0.06^_-0.05_ and an intrinsic
hydrogen column density of 0.17^-0.03^_-0.03_ x 10^22^ atoms cm^-2^. We also
detected the presence of an unresolved Fe K{alpha} line whose equivalent width
is 0.52^+1.0^_-0.1_ keV, in agreement with an old BeppoSAX measurement (Gilli et
al. 2001) in which the reported column density is 1 X 10^22^ atoms cm^-2^.

4. 2007ApJ...671.1388D
Re:NGC 2992
A2.3. NGC 2992- The spatial resolution of the K-band data for NGC 2992 has been
estimated from both the broad Br{gamma} and the nonstellar continuum (see
{section}{section} 2 and 3). The two methods yield symmetric PSFs, with FWHMs of
0.32" and 0.29", respectively, corresponding to 50 pc. The CO(2-0) equivalent
width of ~3 A implies a stellar fraction of ~0.25 within a radius of 0.4", and
hence a stellar luminosity of L_K_ = 3.5 * 10^7^ L_sun_.
Unlike IRAS 05189-2524, the radio continuum in NGC 2992 is quite complex.
Much of the extended emission on scales of a few arcseconds appears to originate
from a superbubble, driven either by the AGN or by a nuclear starburst. On the
other hand, most of the nuclear emission seems to be unresolved. With a beam
size of 0.34" x 0.49", Wehrle & Morris (1988) measured the unresolved flux to be
7 mJy at 5 GHz. At a resolution better than 0.1", Sadler et al. (1995) reported
a 2.3 GHz flux of 6 mJy. Based on this, as well as nondetections at 1.7 and 8.4
GHz, they estimated the core flux at 5 GHz to be <6 mJy. Taking a flat spectral
index, as indicated by archival data (Chapman et al. 2000), one might expect the
5 GHz core flux to be not much less than 6 mJy, leaving room for only ~1 mJy in
extended emission in the central 0.5". If we assume that this difference can be
attributed to star formation, it implies a supernova rate of ~0.003 yr^-1^ and
hence 10^10 {nu}_SN_/L_K_ ~1. Figure 4 shows that a ratio of this order is what
one mig ht expect for ages up to 200 Myr. However, given the uncertainty, it
does not impose a significant constraint.
It is also difficult to quantify what fraction of the narrow Br{gamma} is
associated with star formation. This is made clear in Figure 14, which shows
that the morphology of the line (second panel) does not follow that of the stars
(left panel). In addition, particularly the southwest side is associated with
velocities that are bluer than the surrounding emission, indicative of motion
toward us. The western edge also exhibits high velocity dispersion. Taken
together, these suggest that we may be seeing outflow from the apex of an
ionization cone with a relatively large opening angle. This interpretation would
tend to support the hypothesis that the radio bubble has been driven by the AGN.

5. 2007ApJ...671.1388D
Re:NGC 2992
The stellar continuum appears to trace an inclined disk, the northwest side
of which is more obscured (Fig. 14). However, the velocity dispersion is high,
exceeding 150 km s^-1^ across the whole field (Fig. 15). This is similar to the
160 km s^-1^ reported by Nelson & Whittle (1995) from optical spectroscopy and
suggests that we are seeing bulge stars. To analyze the radial luminosity
profile, we have fitted it with both an r^1/4^ law and exponential profile. The
fits in Figure 16 were optimized at radii r > and then extrapolated inward,
convolved with the PSF. Whether one could claim that there is excess continuum
in the nucleus depends on the profile fitted. The r^1/4^ law provides a stronger
constraint since it is more cuspy, and it suggests that there is no excess.
Although this evidence is inconclusive, Figure 15 suggests that there is some
kinematic evidence favoring the existence of a distinct nuclear stellar
population. This comes in the form of a small unresolved drop in dispersion at
the center, similar to those in NGC 1097 and NGC 1068. While the evidence in NGC
2992 is not compelling, the dispersion is consistent with there being an
equivalent, but fainter, nuclear disk on a scale of less than our resolution of
50 pc. In general, it seems that the K-band light we are seeing is dominated by
the bulge, and we are therefore unable to probe in detail the inner region where
it seems that more recent star formation has probably occurred.
Thus, although the available data suggest that there has likely been recent
star formation in the nucleus of NGC 2992, the only strong constraint we can
apply is that continuous star formation in the central arcsecond over the last
billion years can be ruled out since it would require W_Bt{gamma} > 10-15 A. We
therefore omit NGC 2992 from the discussion and analysis in {section}{section} 4
and 5.

6. 2005ApJ...633..105D
Re:NGC 2992
4.3. NGC 2992 - NGC 2992 exhibits an extended biconical narrow-line region on
kiloparsec scales (Allen et al. 1999), which traces outflowing gas. Veilleux et
al. (2001) were able to model the kinematics in terms of gas rotating in the
disk plane and a biconical outflow, and argue that the latter is a thermal wind
driven by the AGN rather than vigorous star formation. On smaller scales, there
is a figure 8 loop of radio continuum and H? emission, centered on the nucleus
and extending to about 500 pc (Wehrel & Morris 1988). Using adaptive optics to
reach a resolution <0&farcs;2, Chapman et al. (2000) proposed that the loop
structure is in fact a superposition of emission from star formation along a
spiral arm in the disk and outflow bubbles coincident with the larger scale
structures. In contrast to Chapman et al. (2000), our data show a very
significant reduction in the equivalent width of the stellar absorption
features (whether 2.293 micron CO 2-0 or 2.206 micron Na I) at the nucleus,
which is most easily explained in term s of dilution due to hot dust. The
generally accepted classification of NGC 2992 as a Seyfert 2 (or 1.9) is
perhaps surprising given that it exhibits broad emission lines in the optical
and near-infrared. However, given that in the model of Veilleux et al. (2001)
the line of sight is very close to the edge of (but not within) the opening
angle of the outflow from the AGN, a classification close to type 2 makes sense
with respect to the standard orientation-dependent model.

7. 2004MNRAS.350.1049G
Re:NGC 2992
9.14 NGC 2992 This galaxy showed some form of outburst, much more
luminous than any normal supernova, at around JD2447200. The
cross-correlation programme described here does not yield a significant
delay between J and K. However, Oknyanskij & Horne (2001) find 18 +- 10
d between J and K and 84 +- 30 d between J and L. The programme used
here gets a delay of about 35 d between J and L.
The K versus L diagram shows some curvature instead of a linear
relation. Glass (1997a) mentioned that the time constant for the decay
of the outburst at L is considerably longer than that for K.

8. 2004A&A...428..373B
Re:NGC 2992
4.1. NGC 2992. NGC 2992 is a Sa galaxy seen nearly edge-on, which is
interacting with NGC 2993. A prominent dust lane extending along the
major axis crosses the nucleus of the galaxy (Ward et al. 1980). This
galaxy exhibits a biconical galactic-scale out-flow, which emerges
almost perpendicularly from the plane of the galaxy (Veilleux et
al. 2001 and references therein). The existence of an apparently
obscured broad line region lead to its classification as an intermediate
type Seyfert (V6ron et al. 1980).
The nucleus of this so-called 1.9 Seyfert galaxy is highly variable,
and was found to be in a high state at the time of our observations.
Gilli et al. (2000) note more conspicuous IR emission and stronger broad
optical emission lines in their 1999 spectra than seen during its lower
activity state. Indeed, at the nucleus we detect a strong broad
OI{lambda}8446 {Angstrom} emission line, which is a clear signature of a
Seyfert 1 and not seen in Seyfert 2s (e.g. Morris & Ward 1985). Thus,
the properties of this galaxy should be compared to the ones of Seyfert
1s and not Seyfert 2s in any statistical studies, contrary to what is
usually done.
Unfortunately the many emission lines detected in the nuclear spectrum
as shown in Fig. 1, preclude any detailed stellar population study.
Heckman et al. (1995) estimated that 10% of the optical light from a
large aperture centred on the nuclear region (~1-2 kpc) was produced by
a young hot stellar population. In a more detailed IR adaptive optics
study of NGC 2992 Chapman et al. (2000) found that the radial
distribution of the CO index from the inner 3 arcsec (~450 pc),
indicates a strong population gradient within the core, with the stellar
population at the very centre being older than that in the surrounding
regions.
Due to the high inclination of the galaxy and prominent dust-lane, the
host galaxy contribution is much stronger on the NE side of the galaxy
(PA = 55deg). Only one region lying between 160 and 480 pc (mean radius
R = 320 pc) NE from the nucleus provides a spectrum with reasonably high
S/N ratio over the whole wavelength range as required for a detailed
stellar population synthesis.
For this region we deduce that the stellar population is old, and
moderately metallic with no obvious contribution from a starburst (see
Table 2). A reddening correction of up to E(B - V) = 0.43 needs to be
applied to match the observed spectrum with the synthetic one
(Fig. 2). According to Allen et al. (1999), the reddening within the
dust lane is as high as E(B - V) = 1.2, decreasing outwards. We cannot
say whether there is an age gradient towards the nucleus as there are
many broad emission lines (only the conspicuous CAIIT stellar absorption
features are visible) with an apparently strong additional internal
reddening due to dust within the nucleus.

9. 2004A&A...428..373B
Re:NGC 2992
4.1 NGC 2992 is a Sa galaxy seen nearly edge-on, which is interacting with
NGC 2993. A prominent dust lane extending along the major axis crosses
the nucleus of the galaxy (Ward et al. 1980). This galaxy exhibits a
biconical galactic-scale outflow, which emerges almost perpendicularly
from the plane of the galaxy (Veilleux et al. 2001 and references
therein). The existence of an apparently obscured broad line region lead
to its classification as an intermediate type Seyfert (Veron et al.
1980).
The nucleus of this so-called 1.9 Seyfert galaxy is highly variable,
and was found to be in a high state at the time of our observations.
Gilli et al. (2000) note more conspicuous IR emission and stronger broad
optical emission lines in their 1999 spectra than seen during its lower
activity state. Indeed, at the nucleus we detect a strong broad
OI{lambda} 8446 Angstro emission line, which is a clear signature of a
Seyfert 1 and not seen in Seyfert 2s (e.g. Morris & Ward 1985). Thus,
the properties of this galaxy should be compared to the ones of Seyfert
1s and not Seyfert 2s in any statistical studies, contrary to what is
usually done.
Unfortunately the many emission lines detected in the nuclear spectrum
as shown in Fig. 1, preclude any detailed stellar population study.
Heckman et al. (1995) estimated that 10% of the optical light from a
large aperture centred on the nuclear region (~1-2 kpc) was produced by
a young hot stellar population. In a more detailed IR adaptive optics
study of NGC 2992 Chapman et al. (2000) found that the radial
distribution of the CO index from the inner 3 arcsec (~450 pc),
indicates a strong population gradient within the core, with the stellar
population at the very centre being older than that in the surrounding
regions.
Due to the high inclination of the galaxy and prominent dust-lane, the
host galaxy contribution is much stronger on the NE side of the galaxy
(PA = 55deg). Only one region lying between 160 and 480 pc (mean radius
R=320 pc) NE from the nucleus provides a spectrum with reasonably high
S/N ratio over the whole wavelength range as required for a detailed
stellar population synthesis.
For this region we deduce that the stellar population is old, and
moderately metallic with no obvious contribution from a starburst (see
Table 2). A reddening correction of up to E(B-V)=0.43 needs to be
applied to match the observed spectrum with the synthetic one (Fig. 2).
According to Allen et al. (1999), the reddening within the dust lane is
as high as E(B-V)=1.2, decreasing outwards. We cannot say whether there
is an age gradient towards the nucleus as there are many broad emission
lines (only the conspicuous CaIIT stellar absorption features are
visible) with an apparently strong additional internal reddening due to
dust within the nucleus.

10. 2003MNRAS.343..192R
Re:NGC 2992
3.5 NGC 2992 NGC 2992 is a nearby (z = 0.00771; distance = 30.6 Mpc),
almost edge-on, peculiar Sa galaxy with a Sy2 nucleus, interacting with
NGC 2993 at 2.9 arcmin (26 kpc) distance towards SE. A prominent dust
lime roughly north-south along the major axis of the galaxy splits the
nuclear region into two components. NGC 2992 has an unusually extensive
cone emerging almost perpendicularly from the plane of the galaxy up to
~4 kpc (25 arcsec) distance in SE-NW direction (Allen et al. 1999), with
the SE cone brighter than the NW cone. The radio structure of NGC 2992
has major axis PA = 160deg, with a one-sided extension along PA =
130deg, and at smaller scales a 'figure of eight' shape at PA = 160deg
(e.g. Ulvestad & Wilson 1984).
The H- and K-band spectra of NGC 2992 are shown in Figs 2 and 7. The
strongest emission line in the nucleus is the broad Br{gamma}
2.166 {microns}. Other nuclear lines are [Fe II] 1.644 {microns},
He 12.058 {microns}, coronal lines and various H_2_ lines, including
2-1 S(1) 2.248 {microns}. NGC 2992 has been previously observed
spectroscopically in the JHK-bands in 1999 January, and also with SOFI
and a 1-arcsec slit by Gilli et al. (2000). Compared to them, the
emission lines have become brighter and Br{gamma} is much broader
(2530 km s^-1^) than their Pa{alpha}. Furthermore, a relatively strong
[Al IX] line at 2.043 {microns} has appeared.
The most extended line is 1-0 S(l), which can be traced a distance of up
to 7 arcsec (1.1 kpc) perpendicular to the cone but only up to 1 arcsec
(220 pc) parallel to it. Both Br{gamma} and [Fe II] are more extended
(~4 arcsec; 600 pc) parallel to the cone than 1-0 S(1). In addition,
towards the SW H_2_ emission is detected associated with the bridge
connecting NGC 2992 to NGC 2993. This emission is likely to be
shock-excited, as 2-1 S(1) emission is not detected. There are also
separate Br{gamma} regions perpendicular to the cone 5 arcsec (760 pc)
from the nucleus, coinciding with the bar or spiral arms (Fig. 1).
The velocity field of NGC 2992 is shown in Fig. 5. The velocity curve of
[Fe II] is blueshifted by 70 km s^-1^. However, the velocity curve of
Br{gamma} seems to follow H_2_ more closely than [Fe II].
The 1-0 S(1)/Br{gamma} ratio is quite low, 0.28, suggesting thermal UV
heating. The [Fe II]/Br{gamma} ratio is 0.93 and
[Fe II]/Br{gamma}_narrow_ = 16. Considering that [Fe II] is blueshifted in
the nucleus, it is plausible that [Fe II] is excited by shocks. The
narrow Br{gamma} emission may also originate in shocks, as the narrow
Br{gamma}/1-0 5(1) ratio is -0.2, but because Br{gamma} is kinematically
more closely coupled with H_2_ than [Fe II], the shocked regions
producing Br{gamma} are not likely to coincide with [Fe II] regions. In
addition to Br{gamma}, He I is also broad (2200 km s^-1^) (Fig. 10).
The dereddened 2-1 S(1)/1-0 S(1) ratio 0.18 (corresponding to T_vib_ =
2600 K) is in agreement with thermal excitation of H_2_. The density of
the excited molecular hydrogen is NH_2_ = 8.8 x 10^17^ cm^-2^,
corresponding to integrated gas mass of ~500 M_{sun}_. The FWHM size of
the nuclear H_2_ emission is smaller parallel to cone (120 pc) than
perpendicular to it (250 pc).
Three coronal lines [Si VI] 1.964 {microns}, [Si VII] 2.483 {microns}
and [Al IX] 2.043 {microns}) are detected in NGC 2992. In addition,
there appears to be a fairly broad (80 {angstrom}) [Ca VIII]
2.321-{microns} line detected at the 2.5{sigma} level. The coronal lines
are weaker than those in NGC 1068 and 3081 (this paper), and it is not
possible to discuss whether the lines are spatially resolved.

11. 2003ApJ...598..827P
Re:NGC 2992
NGC 2992/2993.-NGC 2992 and NGC 2993 represent an interacting system and
exhibit extended tidal features in the optical images. The MUV
morphology of NGC 2992 shows faint, diffuse emission coincident with the
optical central bulge/disk and with low internal color dispersion. This
galaxy is very faint in the FUV images. NGC 2993 is well detected in
both UIT/FUV and UIT/MUV images. It is also noteworthy that NGC 2993 has
one of the bluest UVoptical colors of the UIT sample. This galaxy is
apparently vigorously forming stars, and these stars dominate the UV
portion of the galaxy's SED. The lack of internal color dispersion
between the MUV and optical images implies that the young stars also
dominate the flux emission at these wavelengths. There is low (but
significant) internal color dispersion between the FUV and MUV images in
NGC 2993, which is centered on the nucleus and may be suggestive of a
dust lane or patchiness in the dust absorption.

12. 2002A&A...386..379R
Re:NGC 2992
NGC 2992: this source shows the strongest long-term
variability in our sample. Our analysis is in agreement
with that of Gilli et al. (2000).

13. 2001ApJS..137..139S
Re:NGC 2992
NGC 2992 and NGC 2993. - We use an H_0_ distance, based on the mean
velocity of the two group members.

14. 2001ApJS..132..129M
Re:NGC 2992
NGC 2992 (Arp 245). - This highly inclined (i >~ 70^deg^) Sa galaxy
hosts a Seyfert 1.9 nucleus and is interacting with the peculiar galaxy
NGC 2993 at a projected separation of ~25 kpc. A strong interaction is
inferred from the tidal tails and connecting bridge observed optically
(Schombert, Wallin, & Struck-Marcell 1990). Optically, NGC 2992 shows a
galactic bulge bisected by a dust lane (Ward et al. 1980). NGC 2992 is
quite faint in the MUV and is not detected in the FUV (Fig. 15a). The MUV
image reveals patchy, diffuse light at the position of the optically
defined bulge (Fanelli et al. 1997a). Despite the AGN emission line
spectrum seen in the optical (e.g., the bright H{alpha} emission shown in
Fig. 15a), there is no evidence of a compact UV nuclear source, most likely
due to the dust lane and high inclination of the galaxy.

15. 2001A&A...368..797P
Re:NGC 2992
NGC 2992: In the case of NGC 2992 and its companion we detect two spatially
separated X-ray components. In Table C.4 of Appendix C we give the sum of
the count rates, fluxes and luminosities for this system. For the
completion of the database we add here the individual values of the source
and the companion. The spectrum of NGC 2992 shows a high absorption and a
low photon index with an integrated flux of
2.815 x 10^-12^ erg cm^-2^ s^-1^ corresponding to a luminosity of
2.616 x 10^41^ erg s^-1^. The spectrum of the companion results in a flux
of 1.061 x 10^-12^ erg cm^-2^ s^-1^ corresponding to a luminosity of
9.987 x 10^40^ erg s^-1^. The spectral fit parameters for the companion are
N_H_fit__ = 0.854 x 10^21^ cm^-2^ and {GAMMA} = -2.72. NGC 2992 is
classified by Lipovetski et al. (1987) as a Seyfert 1.9 galaxy and we found
a variability of this object over short and long timescales.

16. 2000MNRAS.314..573T
Re:NGC 2992
NGC 2992 (Arp 245): This edge-on, interacting galaxy has unusual 'loops'
of diffuse radio emission (Wehrle & Morris 1988; Colbert et al. 1996).

17. 1999ApJ...527..696Q
Re:NGC 2992
H_2_ emission is extended along a P.A. ~20^deg^ similar to that of
the major axis of the galaxy. The most straightforward interpretation is
that it lies in a 800 pc diameter disk in the plane of the galaxy.
H{alpha} + [N II] emission is primarily detected above and below the
plane of the galaxy (Wehrle & Morris 1988; see Fig. 2).

18. 1999ApJ...524..684G
Re:NGC 2992
NGC 2992 is a narrow line X-ray galaxy (Ward et al. 1980). The radio
structure comprises an unresolved nuclear source surrounded by
figure-eight loops (Wehrle & Morris 1988). H I absorption is detected
offset from the radio nucleus against one of the extended lobes. The
host galaxy is viewed nearly edge-on, and so it seems likely that the
H I absorption traces gas in the foreground disk.

19. 1999ApJ...516...97N
Re:NGC 2992
NGC 2992 (Arp 245, MCG-2-25-14):. This galaxy forms an interacting
pair with NGC 2993. RC3 lists log R_25_ = 0.51, but does not give a
major axis P.A. The Extended Southern Galactic Catalog (Corwin et al.
1998, hereafter ESGC), lists galaxy major axis P.A. = 15^deg^ and
diameter = 6.03' x 2.19' in B. Thompson & Martin (1988) used enlarged
Sky Survey prints to measure a major axis P.A. of 18^deg^. DSS images
show that while the galaxy is strongly interacting, the central and
northern parts of the galaxy appear undisturbed and the isophotes show a
consistent major axis P.A.

20. 1998ApJ...495..196A
Re:NGC 2992
3.5.5. NGC 2992
NGC 2992 is an Sa galaxy seen almost edge-on and interacting with NGC 2993. The
K-band image divided by the model of NGC 2992 is presented in Figure 6 (Plate
4) (the image derived from the J-band data shows a similar morphology). The
model-divided result for this galaxy displays a very complex structure. In the
innermost regions, there is a structure at P.A.=37^deg^ seen in excess,
extending approximately 6" (1.3 kpc) from the nucleus to the northeast and 11"
(2.4 kpc) to the southwest. The spiral arms are also visible. The overall
galaxy orientation as derived from the P.A. plot is P.A.=23^deg^ (see Fig. 4e).
The H{alpha}+[N II] image presented in Colbert et al. (1996) shows the presence
of a dust lane that separates the line emission into a double-lobed shape,
extending about 5"-15" in the southeast-northwest direction. A careful
alignment of our model-divided image with the image in Colbert et al. (1996)
shows that the location of the structure seen in our image does not correspond
with the position of the dust lane. Owing to the high inclination of this
galaxy, we cannot discern the nature of this structure. This galaxy also shows
extended emission at L' (Fig. 1e), with the contribution of the unresolved
component to the total observed flux being relatively small (26%) in comparison
with what is found for most of the galaxies in our sample. The P.A. of the 3"
isophotes in the J, H, and K bands are all consistent with the orientation of
the dust lane, while at larger radial distances the P.A. become
23^deg^-26^deg^, presumably tracing the underlying stellar distribution. The
nuclear K-L' colors of this galaxy are the least red of any in our sample
because the L' unresolved component contributes a relatively small fraction of
the total emission.

21. 1997MNRAS.286..513R
Re:NGC 2992
7.1.4 NGC 2992
The 2-10 keV flux of NGC 2992 has been found to have decreased by a factor of
~20 during the past 16 years (Weaver et al. 1996). During that time, its X-ray
spectrum has changed from being that of a typical Seyfert 1 galaxy to an
extremely hard spectrum. The ASCA spectrum is well described by an absorbed
power law with photon index {GAMMA}=1.25, very much harder than any other
source in the present sample, and a narrow (unresolved) neutral iron
fluorescence line with equivalent width 560 eV. Weaver et al. (1996) present a
detailed study of the ASCA spectrum and suggest this spectrum to be dominated
by a Compton reflection continuum that remains once the intrinsically steep
primary continuum has faded (presumably due to light traveltime effects).
Significant neutral absorption and a strong soft excess are also required to
make this hypothesis consistent with the ASCA data. They identify the putative
molecular torus as a natural site for the origin of this time-delayed
reflection continuum.

22. 1997ApJS..113...23T
Re:NGC 2992
A9. NGC 2992
NGC 2992 is a nearby (z=0.0077) galaxy, highly inclined to our line of sight
(i=70^deg^) with a prominent dust lane crossing the nucleus of the galaxy (Ward
et al. 1980). The X-ray spectrum is heavily absorbed (Turner & Pounds 1989),
although it is observed to turn up again at low energies in some data sets
(see, e.g., Reichert et al. 1985). There is some evidence for extended soft
X-ray emission on a 2 kpc size scale (Elvis et al. 1990). Weaver et al. (1996)
combined information from all X-ray observations of the source, revealing
variability by a factor 20 in the 2-10 keV continuum flux over 16 yr, an order
of magnitude more than the variability observed in the flux of the iron K-shell
fluorescence line, suggesting large lags (estimated to be ~10 yr) between
direct and reprocessed flux. Those authors conclude that the inferred time
delay and the narrow width of the iron K-shell line rules out reprocessing in
an accretion disk, and they attribute the iron line to the putative molecular
torus.

23. 1997ApJ...477..631V
Re:NGC 2992
NGC 2992 = MCG -02-25-14
The optical spectrum of the narrow-line X-ray galaxy NGC 2992 is fairly
typical of that of a normal Seyfert 2 galaxy with the exception of a
possible weak broad component to H{alpha} (Shuder 1980; Veron et al.
1980). In contrast, broad emission is clearly observed in the profile of
Pa{beta} (Paper I; Rix et al. 1990). The K-band spectrum of NGC 2992 is
characterized by weak Br{gamma} emission but relatively strong H_2_
emission (Fig. 1f). There is a slight excess of broad emission with
FWHM ~ 4000 km s^-1^ on each side of narrow Br{gamma}, but it may simply
reflect structure in the underlying stellar continuum or small errors in
the continuum calibration. Consequently, the flux of Br{gamma}_b_ listed
in Table 3 should be considered an upper limit.
A direct estimate of the reddening in the BLR of NGC 2992 can be
derived from the intensity of the broad line at Pa{beta} and Br{gamma}:
assuming Case B recombination, E(B - V)_b_ = 2.1. The broad H{alpha}
fluxes measured by Shuder (1980) or Veron et al. (1980) can also be used
to determine the extinction toward the BLR. Using the value of Veron et
al. (1980), E(B - V)_b_ ~ 2.6 from Pa{beta}/H{alpha} and 2.5 from
Br{gamma}/H{alpha}, while the H{alpha}_b_ flux of Shuder (1980) implies
E(B - V)_b_ ~ 0.9 from Pa{beta}/H{alpha} and 1.2 from Br{gamma}/H{alpha}.
The color excesses derived from the narrow lines of NGC 2992 show a
tendency to decrease with wavelengths. This result is difficult to
explain unless differential slit loss, seeing, and guiding effects are
affecting the data on this object. This may be the case since the line-
emitting region in NGC 2992 is known to be extended and complex (Wehrle &
Morris 1988).

24. 1997A&A...327..493R
Re:NGC 2992
NGC 2992 is strongly interacting with NGC 2993. HI observations were carried
out by Mirabel & Wilson (1984). The HI line has a total FWZI of 600 km/sec. The
narrow HI peak at a higher velocity is probably related to the tidal tail to
the north. The CO line profile is very flat topped and is well fit by two
gaussians of unequal heights, one at 2128 and the other at 2395 km/sec. The
flat-topped CO profile implies that the CO gas is concentrated in the inner
parts of the galaxy. The HI and CO FWHM beamsizes are 3.3' and 23"
respectively, therefore it is tempting to conclude that the emitting region
must be of the order or smaller than 23"=5.35 kpc in diameter, so most of the
H_2_ gas is located in the central parts of the galaxy.

25. 1997A&A...319...33A
Re:NGC 2992
NGC 2992 This field is pictured in Fig. 5 on the same scale as NGC 4258 which
is shown in Fig. 2. NGC 2992 has sources in the same kind of "X" pattern as in
the NGC 4258 case but the NGC 2992 sources are fainter and at greater
separation. However, there are more sources along the lines in NGC 2992,
suggesting a connection back to the central active pair of galaxies (notice
particularly the line of sources SW toward C=3.2, 3.6 and C=4.7).
An optical photograph of the disturbed pair of central galaxies can be seen in
Atlas of Peculiar Galaxies #245 (Arp 1966). The sources in both the outer
region (Fig. 18) and the inner region (Fig. 5) are identified in Table 3.
Some of the identifications are particularly interesting. The C=111.0 source is
a very blue compact galaxy in a group of red objects, a group which contains
some other very blue objects. The 4.7 source is detected as 3 sources close
together. Aside from the obvious BSO at this position there is also a BSO at
m_J_=18.3 mag. and 09/44/29.4 - 14/37/03.

26. 1996ApJS..105...75C
Re:NGC 2992
4.1.6. NGC 2992
A dust plane separates the line emission that immediately surrounds the nucleus
(see Fig. 1f) from the bright (L_H{alpha}+[N II]_ = 3.6 x 10^40^ ergs s^-1^)
ELR which extends from ~5"-15" (0.6-2.2 kpc) to the northwest, in the
direction of the minor axis. A number of ionized filaments of luminosity
~10^38^ ergs s^-1^ are also present beyond the northwest ELR, at distances
<= 30" (4.5 kpc). Such bright filamentary structures are commonly found in
luminous IR galaxies with starburst-driven superwinds (e.g., Heckman et al.
1990). Long-slit spectroscopic data taken by Tsvetanov, Dopita, & Allen (1995)
shows evidence for outflowing gas that has velocities up to 200 km s^-1^ and
extends several kiloparsecs out of the galaxy disk. Radio continuum maps of the
nuclear region of NGC 2992 show emission extending out to 2" (0.3 kpc) along
the minor axis which has the structure of "striking pair of loops" (Wehrle &
Morris 1988; see also Paper II). These authors interpret these loops as
limb-brightened bubbles or magnetic arches. The bright minor axis optical ELRs
and "figure eight" radio morphology suggest that a powerful galactic outflow is
occurring in NGC 2992.
Our H{alpha} + [N II] image (Fig. 1g) shows emission from the disk but no
extended emission along the minor axis.

27. 1996ApJ...467..551C
Re:NGC 2992
3.1.9. NGC 2992
In Figure 1e, we show contour maps of the radio emission from NGC 2992. The
nuclear radio source is surrounded by fainter emission with complex structure
extending in nearly all P.A.'s on a scale of ~20"-30" (3-4.5 kpc). Extraplanar
emission to the east and west is noticeable in the normal and tapered images.
The large-scale 20 cm map from Hummel et al. (1983, reproduced in Figure 1e;
see also map in Ward et al. 1980) clearly shows extraplanar emission extending
to the east, but this emission is not well imaged in our 4.9 GHz (6 cm) maps.
By comparing the map of Hummel et al. with a map made from our data which has
the same beam size, we find that the eastern "arm" of radio emission has a very
steep spectrum ({alpha} >~ 2; S_{nu}_ is proportional to {nu}^-{alpha}^). On
smaller scales, the nuclear morphology consists of a compact source plus
surrounding diffuse emission (Ulvestad & Wilson 1984) which resembles a
"striking pair of loops" extending ~2" (0.3 kpc) north (and south) from the
compact nuclear source in P.A. ~0^deg^ (Wehrle & Morris 1988).

28. 1995ApJ...447..121W
Re:NGC 2992
NGC 2992.-We measure a significant Fe K feature that is inconsistent with
being produced by cold iron at the systemic velocity of the galaxy. An Fe
K line was detected by Ginga having an EW of 438 +/- 88 eV (NP94). There
was also a marginal detection of an Fe K line with EXOSAT (Leighly et al.
1989). The upper limit on N_HFe_ is about,1/2 the Ginga detection;
however, the H column density during the HEAO 1 epoch was only 1/3 that
measured by Ginga (NP94).

29. 1994CAG1..B...0000S
Re:NGC 2992
Pair [with NGC 2993]
Sa(tides)
(E,L,1)
CD-807-S
Feb 25/26, 1979
103aO + GG385
45 min
The orientation of the print here is north at
the top, east to the left. NGC 2992 is to the north
and west of NGC 2293, which has the more
circular image. The projected separation of the
pair is 3'. The redshifts are v_o(2992) = 1963 km/s
and v_o(2993) = 1868 km/s, giving a redshift
distance of 38 Mpc (H = 50) based on the mean
redshift. The projected linear separation of the
pair is, then, small at 33 kpc.
Tidal interaction is clearly visible.
Luminous material exists between the main
bodies of the principal components, extending
from NGC 2293 to the shred on the north side of
NGC 2992. This apparently torn-away part of
NGC 2992, of low surface brightness, is evidently
a tidal plume that nevertheless has knots that
are presumably small HII regions.
The smooth extended arm that starts on the
north edge of the southern component of the pair
(NGC 2993) and extends eastward, appears also
to be a tidal plume.
The prints in the right column are from the
same plate used for the main print at the left. The
top print in this column shows that the shred torn
from NGC 2992 and the tidal-plume arm in NGC
2993 are both of low surface brightness relative
to the central regions of each galaxy. These
central regions are shown in the lower two prints
in the right column. Not shown well here but
visible on the plate is evidence of recent star
formation in the center of NGC 2992; hence its
assigned type is Sab.

30. 1991ApJ...381...85T
Re:NGC 2992
The SSS 338/78 data were not usable. Analysis of the second data set showed
an improved fit with either the addition of a soft excess (Tables 3-4) or
parameterization of the absorber as partial covering with 82% of the source
covered by a column of 1.6 (1.0-2.21) x 10^22^ cm^-2^ see section 2.3.2).
Alternatively, the soft emission in this source may arise in some extended
region, as reported in an Einstein HRI observation of this source
(Fassnacht et al. 1990).

31. 1988A&AS...75..273D
Re:NGC 2992
NGC 2992 is an Sa type galaxy seen nearly edge-on, crossed by a dust
lane and interacting with NGC 2993. It has been well studied at all
wavelengths. NGC 2992 is a radio source showing an extension along
PA = 100^deg^ (Ward et al., 1980, Nummel et al., 1983), diffuse radio
emission (Ulvestad and Wilson, 1984b), and several compact nuclear
radio sources (Condon et al., 1982, Unger et al., 1986). NGC 2992 is
also an X-ray emitter (Marshall et at 1981, Mushotzky, 1982);
Reichert et al. (1985) and Singh et al. (1985) have interpreted its
X-ray spectrum as due to a central source partially covered by patchy
absorbers, and Barr and Mushotzky (1986) have shown it to be variable
on a timescale of a few days. NGC 2992 is also rich in HI
(Huchtmeier, 1982) and in CO (Sanders and Mirabel, 1985).
The nuclear properties of NGC 2992 at optical wavelengths have been
analysed in detail with different spectral resolutions and apertures.
The first spectra were obtained by Burbidge et at (1972) and Osmer et
al. (1974); then, Veron et al. (1980), Shuder (1980) and Ward et al.
(1980) all found this galaxy to have a broad component in H{alpha},
and therefore classified it as an intermediate type Seyfert. The same
result was derived from the shape of its overall far-IR to far-UV
continuum (BD86). However, no broad H{beta} component has yet been
reported in this galaxy. A kinematic study of the ionized gas
surrounding NGC 2992 has recently been achieved by Colina et al.
(1987) from high spectral resolution long slit spectroscopy, but these
authors did not discuss the physical properties of the ionized
nebulosity.
We find a nuclear redshift z = 0.0077 +/- 0.0002, corresponding to a
galactocentric velocity of 2055 km s^-1^ and to a distance (averaged
with that of NGC 2993) of 42.0 Mpc.
We have detected ionized gas in NGC 2992 over 42.5" (8.4 kpc) along
PA = 197^-1^, a size comparable to that observed by Neckman et al.
(1981) and somewhat larger than the 35" detected by DB87 through
H{alpha} + [NII] narrow band imaging. The ionized nebulosity is much
fainter towards the north-east than towards the south- west (see
Fig. 12 and Tab. XIVa), as already noted along PA = 206^deg^ by Colina
et al. (1987). These authors explained the asymmetry of the ionized
gas distribution by the existence of a dust lane to the south of the
nucleus of NGC 2992, which can prevent the nuclear ionizing radiation
from reaching some of the outer zones. This hypothesis is confirmed by
the larger value of E(B-V) towards the north-east, as well as by the
decrease of the emission line intensities in this direction.

32. 1988A&AS...75..273D
Re:NGC 2992
The reddening in NGC 2992 is important: from the H{alpha}/H{beta}
ratio, we derive E(B-V) = 0.84 in the narrow line region. Malkan
(1983) estimated the same amount of reddening from the [SII]
(4069+4076)/(6717+6731) ratio. McAlary et al. (1986) computed a value
of E(B-V) only a little smaller using the Br{gamma}/H{beta} ratio, and
interpreted this difference as due to the contribution of the broad
line region, which is larger in Br{gamma} than in H{beta}. However,
Ward et al. (1987) recently derived the reddening of the BLR from the
broad P{beta}/H{alpha} ratio, and found a colour excess similar to
that of the NLR. Using the values of E(B-V) estimated from the narrow
H{alpha}/H{beta} ratio to correct the line intensities for reddening
(Tab. XIVa) we find from the [OIII] line ratio T_e_ = 19900 K in the
nucleus.
The excitation level of the gas decreases from the nucleus to the
outer regions. Our relative emission line intensities in the nucleus
agree with those of Shuder (1980) and Ward et al. (1980, whose signal
to noise is notably lower than ours or Shuder's), except for
[OII] 3727, which we find 50% larger, and for the red end of the
spectrum, where both papers give much larger values of H{alpha}, [NII]
and [SII].
NGC 2992 shows a rather smooth velocity field, with the velocity
increasing quite regularly towards the south- west. There may be solid
body, rotation of the ionized gas in the nuclear zone, with a velocity
gradient of 100 km s^-1^ kpc^-1^ over about 4 kpc (Tab. XIVb) and a
total velocity amplitude of 320 km s^-1^. The rotation curve somewhat
flattens in the outer zones. Colina et al. (1987) have mapped the
velocity field of NGC 2992, in particular along PA = 26^deg^ =
206^deg^, close to our slit position angle (197^deg^) and find
comparable results. However, their high spectral resolution data
extend over 18" only (instead of 42" for our data).

33. 1976RC2...C...0000d
Re:NGC 2992
Part of Arp 245
Interacting pair with NGC 2993 at 2.9 arcmin
faint outer extension with knots at end.
Blue stellar object (= Weedman 2) at 2.5 arcmin north.
Photograph and Spectrum:
Ap. J. (Letters), 178, L43, 1972.
Photometry and Spectrophotometry:
Ap. J., 192, 279, 1974.

34. 1968MCG4..C...0000V
Re:MCG -02-25-014
Outstanding, bright interacting pair with MCG -02-25-015
{rho} = 3.0 arcmin.
Linked with wide arches, nicely visible.
Photo: Arp 245.
Perturbation inside bright arm;
to the northeast trails a wide and amazingly long tail.
One of its arms could be, however,
two to three overlapping galaxies.
Type:
vdB - Pec tt
Morg - g?Sp
deV - Sap

35. 1964RC1...C...0000d
Re:NGC 2992
Small, bright nucleus. Asymmetric arms with dark lanes. Very faint
outer extensions.
Interacting pair with NGC 2993 at 2.9 arcmin.


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