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Notes for object NGC 4450

17 note(s) found in NED.


1. 2009A&A...503..409H
Re:NGC 4450
No significant polarized emission is detected in this galaxy. The almost equal
double and brighter lobe of a triple in the field allow consistent assessment of
the Galactic foreground RM of -8 +/- 1 rad m^-2^.

2. 2008MNRAS.385..553D
Re:NGC 4450
NGC 4450: The FP data of this anemic galaxy have been presented in
Chemin et al. (2006a). The H{alpha} distribution is very clumpy and the
velocity field perturbed in the innermost regions of the galaxy. A new
tilted-ring model is fitted to the velocity field using rings of 4
arcsec width instead of 2 arcsec in our previous analysis. This allows
one to derive a new major axis PA of 353 +/- 5deg with a smaller error
bar than in Chemin et al. (2006b). The values remain in agreement within
the errors.

3. 2006MNRAS.366..812C
Re:NGC 4450
Like in the H I data of Cayatte et al. (1990), this anaemic galaxy has a patchy
H{alpha} distribution. The H{alpha} spiral appears highly wound around the
centre. The velocity field appears significantly dispersed in the galaxy inner
parts as well as in the outer ones but to a lesser extent. The nucleus displays
a steep gradient (~200 km s^-1^), which result was already seen in long-slit
data (Rubin et al. 1999). Little CO gas is observed in NGC 4450 (Helfer et al.
2003).

4. 2005ApJ...627..674A
Re:NGC 4450
NGC 4450.Although essentially unresolved in the VLBA study of A04, this galaxy
has about 10 mJy of extended emission in our VLA images, about twice as much as
is present in the core. Because of the extensive extended emission, we classify
the variability as tentative, although we find no signs of u-v effects in the
flux variations.

5. 2002ApJS..143...73E
Re:NGC 4450
NGC 4450.---SBab: Nuclear point source embedded in a luminous
elliptical bulge. The bulge is threaded by a wide high-contrast bar,
with a P.A. ~20deg offset from that of the bulge. Two tightly wrapped,
narrow, low-contrast arms emerge from the ends of the bar and can be
traced through several turns before fading into the ambient disk. The
P.A. of the outer disk isophotes is aligned with that of the bulge
and not that of the bar.

6. 2002ApJS..139....1T
Re:NGC 4450
NGC 4450 (L1.9).-The ROSAT PSPC image is dominated by a pointlike
nucleus (Halderson et al. 2001). The serendipitous source seen in the
PSPC image (~3' NE of the nucleus, Komossa et al. 1999) is not clearly
present in the ASCA data.

7. 2001ApJS..133...77H
Re:NGC 4450
NGC 4450 (L1.9). - The nucleus of this galaxy is classified as a
LINER 1.9 and is not formally part of our Seyfert sample. We detected a
central, unresolved core, with a flat or mildly inverted spectrum
({alpha}_6_^20^ = 0.07). The previously reported measurement at 20 cm
(Hummel et al. 1987; S_20_ = 5.3 mJy, {DELTA}{theta} = 1.3") agrees
reasonably well with ours.

8. 2001AJ....122..637H
Re:NGC 4450
NGC 4450. - Komossa, Bohringer, & Huchra (1999) found, as we did, that
a single power law with N_H_ close to the Galactic value provides an
excellent fit to the soft X-ray spectrum. From this model, they derived a
flux consistent with our own.

9. 2001A&A...368...16M
Re:NGC 4450
33. NGC 4450 a Virgo cluster galaxy, is an Sab spiral of medium inclination
with soft spiral arms. The galaxy shows an inner structure with a slight
different position angle ({DELTA}PA ~ 5^deg^) compared to the disk. This
may be interpreted as a lens or bar (Rubin et al. 1997; Eskridge et al.
2000). Nevertheless, our fit lead to good results.

10. 1999A&A...349...88K
Re:NGC 4450
4.6. NGC 4450
A fairly weak broad H{alpha} line is probably present in the optical
spectrum (Stauffer 1982, H97). For an optical image see, e.g., Sandage
(1961). The HII region population of the galaxy was studied by
Gonzalez Delgado et al. (1997). An Einstein IPC image is shown in
Fabbiano et al. (1992). They derive an (0.2-4 keV) X-ray flux
f_X_ = 11.5 10^-13^ erg cm^-2^ s^-1^ under the assumption of a thermal
bremsstrahlung spectrum with kT=5 keV.
Again, we do not detect short-timescale variability.
The source is quite bright and nearly 2000 photons are available
for the spectral analysis (we used the deepest pointing). No
Raymond-Smith fit is possible. When allowing N_H_ to be free, it
underpredicts the Galactic value. If subsolar abundances are allowed,
the best fit requires abundances less than 1/100 solar and that fit is
still unsatisfactory. In contrast, a single powerlaw with
{GAMMA}_X_ = -2.0 near the AGN-canonical value (e.g., Pounds et al.
1994; Svensson 1994) gives an excellent fit. If N_H_ is treated as free
parameter, the Galactic value is recovered. We derive a soft X-ray
luminosity of L_X_ = 10^10.8^ erg s^-1^, the highest value found among
the present galaxies. The corresponding (0.5-4.5 keV) X-ray luminosity
is L_X_^0.5-4.5keV^ erg s^-1^, a factor ~5 above the value expected
from the stellar contribution using the relation of Canizares et al.
(1987). We note that Tully's catalog places NGC 4450 at the distance of
the Virgo cluster. If the galaxy is instead located in the sheet of
galaxies behind the Virgo cluster, the luminosities inferred above
increase correspondingly.
A comparison with the PSF of the PSPC shows that most of the X-ray
emission is consistent with arising from a point source. At weak
emission levels there is evidence for source extent (Fig. 3; several of
the structures are seen in both, the soft (0.1-0.5 keV) and hard
(0.5-2.4 keV) band). Again, there is a nearby second source. Its
countrate is 0.011 +/- 0.002 cts/s and since the pointing is deep, a
spectral analysis is possible. A powerlaw spectral fit gives a spectrum
similar to NGC 4450 itself, but a bit softer with {GAMMA}_X_ = -2.4. At
the distance of NGC 4450 this corresponds to a luminosity of
L_X_ = 7 10^39^ erg s^-1^. The source is also present in the second PSPC
pointing of slightly lower exposure time (Table 1). Its countrate is
constant. Inspection of the POSS plates does not reveal any optical
counterpart. Neither is there any X-ray source visible in the Einstein
IPC image (see Fig. 7 of Fabbiano et al. 1992). The 'reality' of these
nearby sources is examined in Sect. 4.9.

11. 1997ApJS..112..391H
Re:NGC 4450
NGC 4450.--The narrow-line profiles of this LINER show extended, slightly
asymmetric wings that largely contribute to the broad base of the complex (Fig.
12f). However, additional low-level emission extends beyond the wings of
[N II], and a full analysis of the blend indicates the probable presence of a
fairly weak (f_blend_~20%; FWHM~2300 km s^-1^) broad H{alpha} line, confirming
the suggestions of Stauffer (1982) and Paper I.

12. 1997ApJS..108..155G
Re:NGC 4450
NGC 4450 shows a compact nucleus and a very faint tail of ionized gas
that ends in a weak knot at 25" from the nucleus at P.A. = 354^deg^ in
the north.

13. 1994CAG1..B...0000S
Re:NGC 4450
Hubble Atlas, p. 13
Sab pec
H-2432-H
May 17/18, 1947
103aO
25 min
The image of NGC 4450 here was made from the same Mount Wilson
100-inch plate used in the Hubble Atlas. The description there says
"there is no doubt that this galaxy has the same soft massive arms as
NGC 4826 [left column here], NGC 4569 [preceding panel] and NGC 4579
[two panels back]."
The unusual feature of the thin dust lane is its place of origin
far from the center near what appears to be a small HII region.

14. 1976RC2...C...0000d
Re:NGC 4450
Photometry and Isodensitometry:
Ap. J. Suppl., 26, No. 230, 1973.

15. 1973UGC...C...0000N
Re:UGC 07594
SA(s)ab (de Vaucouleurs), Sb- (Holmberg)
Companion 3.8, 342, 0.3 x 0.2, spiral

16. 1964RC1...C...0000d
Re:NGC 4450
Small, very bright, diffuse nucleus in a smooth bulge with strong, regular
dark lanes. Smooth arms with a few condensations. Pseudo (R): 3.4 arcmin x
2.1 arcmin.

17. 1961Hubbl.B...0000S
Re:NGC 4450
Sb
H-2432-H
May 17/18, 1947
103aO
25 min
Enlarged 4.0X
This galaxy is an intermediate case of the NGC 4826 Group.
The plate was taken with the 100-inch after the war, when
the city lights from Los Angeles were bright. The faint
outer detail is lost because of the bright background sky.
There is no doubt, however, that this galaxy has the same
soft, "massive" arms as NGC 4826, NGC 4569, and NGC 4579. The
internal dust lanes are quite regular. The most conspicuous
lane does not start in the nuclear region but begins abruptly
some distance from the center -- an unusual feature in
galaxies.


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