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Notes for object NGC 5643

21 note(s) found in NED.


1. 2007A&A...461.1209D
Re:NGC 5643
NGC 5643: The source was proposed as a Compton-thick one by Maiolino
et al. (1998). Here this result is confirmed. The poor statistics
prevent any detailed modelization of the X-ray spectrum, but the huge EW
of the FeK{alpha} line (EW ~ 1.2 keV) strongly supports this scenario. A
possible soft excess is present although it is not constrained by the
present data (since the exclusion of the LECS instrument). However, it
is most probably associated with a warm scattering and/or thermal
component (Maiolino et al. 1998).

2. 2006A&A...448..499B
Re:NGC 5643
3.2.7 NGC 5643 The XMM-Newton observation suggested a complicated picture for
NGC 5643, with a heavily absorbing column density which likely obscures part of
its own Compton reflection at high energies and a soft X-ray spectrum dominated
by mainly unresolved emission lines produced in a photoionized plasma. Other
possibilities cannot be, however, ruled out (Guainazzi et al. 2004). The hard
X-ray flux measured with Chandra is consistent with the one found with
XMM-Newton, while the soft fluxes, though marginally, are not in agreement.
The quality of the Chandra spectrum of NGC 5643 is not good enough to perform
a detailed analysis in the soft band. However, a reasonable broad band fit (
{chi}^2^ = 5/10 d.o.f.) is achieved with a pure Compton reflection component, an
iron line and a steep ({GAMMA} > 3) powerlaw to model the softer part of the
spectrum. The strong iron line is confirmed by the local fit (see Table 2). In
this source, the statistics do not allow us to check if this component may be
reproduced by the blending of the emission lines expected from a photoionized
plasma, even if the XMM-Newton analysis revealed that this is indeed possible
(Guainazzi et al. 2004). However, the thermal model with two MEKAL components
gives a fit of similar quality ({chi}^2^ = 3/7 d.o.f.), with temperatures of
0.15 and 0.62 keV and a metal abundance lower than 0.08 times the solar.

3. 2003ApJS..146..353M
Re:NGC 5643
NGC 5643 (GD)
This well-defined, symmetric grand-design nuclear dust spiral is
another prototype of its class. While there are other dust spirals
present in the circumnuclear region, the two main dust arms are wider
and have greater contrast. The peak nuclear brightnesses at V and H
are slightly offset from one another, which is presumably due to dust.

4. 2002ApJS..143...73E
Re:NGC 5643
NGC 5643.---SB(r)a: Bright nuclear point source, embedded in slightly
elliptical bulge. Bulge is threaded by a narrow, prominent bar. Bar
and bulge major axis are misaligned by ~30deg, but there is an
isophotal twist in the bulge, such that the bar and bulge isophotes
align at low intensity. Bright spiral arms begin at the ends of the
bar. The spiral structure is flocculent and asymmetric, but features
can be traced out for several windings. The arms are rich in
star-forming knots, and filamentary structure.

5. 2002A&A...391...83B
Re:NGC 5643
NGC 5643 (Fig. 23) has strong, diffuse radio emission from the nucleus,
the bar and the disc. The central region and outer disc are weakly
polarized with some indication of a spiral pattern.

6. 2002A&A...389...68G
Re:NGC 5643
NGC 5643: the catalog of HII regions has an irregular
distribution. The outer parts look also irregular in the
galaxy images. Thus, our two methods as well as the
photometric values are very unsafe. For lack of any stronger
criteria, we adopt the results of the first method, which
give a rounder deprojected object. It should nevertheless
stressed that is a very unsafe estimate.

7. 2000ApJ...544..747S
Re:NGC 5643
The near-UV W values, CR, and spectrum can be best reproduced by the
combination of the bulge template plus 1% in mass of a 100 Myr stellar
population, except for the Ca II K line, mostly because of the lower
metallicity of the young template, as discussed previously. The HOBL can
be identified (Fig. 17b). Ne III {lambda}3968 + H{epsilon} emission are
almost filling the Ca II H + H{epsilon} absorption.

8. 1999ApJ...527..696Q
Re:NGC 5643
Strong H_2_ emission is observed near the nucleus as well as extended
emission coincident with some of the features seen in line emission,
such as [O III]. The overall shape of the line emission is similar to
but not coincident with dust lanes seen in the optical/near-infrared
(F814W/F160W) color map (Quillen et al. 1999). East of the nucleus the
radio jet (P.A. 87^deg^) lies along the southern edge of the ionization
cone (Simpson et al. 1997; see Fig. 3).

9. 1999ApJ...516...97N
Re:NGC 5643
NGC 5643: RC3 lists log R_25_ = 0.06 and does not list a major axis
P.A. The ESO catalog lists the galaxy diameter as 6' x 5.5' in B.
de Vaucouleurs (1977) gives a galaxy diameter of 5.37' x 4.79',
while Corwin et al. (1985) give 6.92' x 6.46'. Morris et al. (1985)
measure a photometric major axis P.A. of 128^deg^ +/- 10^deg^
and a kinematic major axis P.A. of 13.65^deg^ +/- 2.5^deg^.

10. 1998MNRAS.297..579C
Re:NGC 5643
NGC 5643. This galaxy was classified by Phillips et a. (1983) as a
low-luminosity Seyfert 2. Schmitt et al. (1994) presented [O III] and H{alpha}
images, as well as optical spectra of NGC 5643. The images show the
high-excitation gas to be extended along the east-west direction by ~20
arcsec. The stellar population is moderately old in the central region. showing
evidence of absorption lines diluted by a blue continuum. supposed to be
scattered nuclear light.
The Ws of this galaxy present a mild gradient to the east of the nucleus
(i.e. towards negative r in Fig. 25), suggesting the presence of scattered light
up to at least 4 arcsec from the nucleus. In the outer regions, the Ws
correspond to S3-S4 templates, while the continuum ratios correspond to S3 to
the east of the nucleus and S1 to the west. Bonatto et al. (1989) obtained that
the nuclear stellar population of this galaxy can be represented by an S3
template, similar to our result.

11. 1998AJ....116.2682C
Re:IRAS 14294-4357
NGC 5643. Seyfert 2.

12. 1997ApJS..110..299M
Re:NGC 5643
Bar is visible in both the ellipse fits and the K_S_image.

13. 1997A&AS..125..479J
Re:NGC 5643
NGC 5643 (SABc/Seyfert 2, 1"~66 pc, I=28.8^deg^)
Despite the low disk inclination, there is a strong twist ({delta}PA=44^deg^
between a=3" and 30") inside the large-scale bar. This is interesting, because
NGC 5643 belongs to late-type (Sc) galaxies - which are expected not to show a
twist (Elmegreen et al. 1996) - and, at the same time, has a Seyfert nucleus.

14. 1996ApJS..103...81C
Re:NGC 5643
NGC 5643.--Seyfert 2.

15. 1994CAG1..B...0000S
Re:NGC 5643
SBc(s)II-III
CD-1342-S/Br
March 14/15, 1980
103aO + GG385
40 min
Although NGC 5643 is in low Galactic
latitude (b = 15^deg^) with the attendant high
foreground contamination, it is nevertheless
clear that robust current star formation is occurring
in the nearly circular arms; very many HII-region
candidates exist. Individual stars also
begin to resolve at about B = 22.
The central region is oval rather than
bar-like. The straight, thin dust lane on one side
of the center, characteristic of barred spirals, is
evidence for strong noncircular motions in the
neighborhood of the central oval potential; the
lane is the response of the gas to hydrodynamic
shocks due to these noncircular motions.
The faintness of a corresponding straight
lane on the opposite side of the center may be an
aspect effect; these lanes may not lie entirely in
the plane of the disk, evidenced also by their
crossing over and under the nuclear region, as is
clear in NGC 5383 (SBb; Hubble Atlas, p. 46;
panel 168 here).
The redshift of NGC 5643 is v_o = 947 km/s.

16. 1993ApJS...88..415R
Re:NGC 5643
Although NGC 5643 clearly has a bar, the arms start so close in and wrap
so tightly that it is not obvious from a broad-band image. The outer
western arm appears to originate just outside the western edge of the
bulge, cross the bar at about the same radius on the eastern side, then
carry on back around to the west, passing its point of origin again some
25" further out. The H{alpha} image brings out another arm to the north
whose point of origin is not clear. The clumping of H II regions near the
east and west edges of the bar are apparently real, as the outermost
isophotes suggest a disk orientation not far from face-on. Continuum
subtraction reveals an excess of H{alpha} emission in the bulge, but none
linking it with the arms. NGC 5643 is also a Type 2 Seyfert with an
interesting velocity field (Morris et al. 1985).

17. 1993ApJS...86....5K
Re:NGC 5643
NGC 5643; SBc, Seyfert 2.
The nucleus of this almost face-on barred spiral (Morris et al. 1985)
shows high-excitation optical emission lines. These characteristics are
suggestive of the nonthermal nuclear activity in Seyfert 2 galaxies.
However, its luminosity is lower than that of a "classical" Seyfert 2,
and thus it has been classified as a Seyfert 2-like galaxy by Phillips
et al. (1983). It is also a strong nuclear radio emitter and an "extreme
infrared" galaxy, that is, a galaxy for which the ratio between the IR
(80 micron) emission and the B-band flux (per logarithmic frequency
interval) is up to 250 (Antonucci & Olzewski 1985). The UV spectrum is
noisy with very low signal-to-noise ratio in the short-wavelength region,
but a few emission lines typical of Seyfert activity are clearly visible,
such as C IV, C III], [Ne IV]> {lambda}2424, and, marginally, Mg II.

18. 1985SGC...C...0000C
Re:NGC 5643
Plate 2286
Overexposed center, bar with dust, (r'): 1.3 x 1.1, very knotty arms.

19. 1979AJ.....84..472S
Re:NGC 5643
Well-defined thin, lumpy arms, with good possibility
of resolved HII regions at the 2-3 arcsec level.

20. 1976RC2...C...0000d
Re:NGC 5643
Spectrum:
Bull. A.A.S., 4, 237, 1972.
Radio Observations:
Australian J. Phys., 16, 360, 1963.

21. 1964RC1...C...0000d
Re:NGC 5643
Very small, very bright nucleus. Very faint bar. Hexagonal pseudo (r):
1.1 arcmin x 1.0 arcmin. 2 main, partially resolved arms with branches.
HA 88, 2 dimensions (2.5 arcmin x 2.3: arcmin. series a) for bright part only;
see HB 914, 7, 1940.
Photograph:
Occ. Notes R.A.S., 3, No.18, 1956.


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