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Notes for object NGC 4643

14 note(s) found in NED.


1. 2005MNRAS.362.1319L
Re:NGC 4643
NGC 4643. This is a famous barred Polar Ring galaxy (Whitmore et al. 1990),
studied previously also by ES03. They found an elliptical inner structure in the
optical region, and based on an unpublished high-resolution H-band image by
Knapen that structure was interpreted to be an inner ring. Our K_s_-band image
shows four knots in the central part of the galaxy, which most probably
indicates the presence of a nuclear ring (Fig. 5).

2. 2005MNRAS.362.1319L
Re:NGC 4643
NGC 4643. For this galaxy the best decomposition also included, besides the
bulge and the disc, a bar and an oval. The bar model was improved using n_bar_=
1. Also, automatic fitting created a slightly too long bar, so that the bar was
forced to have a length that gave the smallest residuals. The automatic
procedure easily makes a too long bar if there is an inner ring surrounding the
bar.

3. 2004A&A...415..941E
Re:NGC 4643
NGC 4643: Listed as an "inner-disk" galaxy by Erwin & Sparke (2003);
higher-resolution I-band images (courtesy Johan Knapen) and unpublished H-band
images from the William Herschel Telescope appear to confirm the alternate
hypothesis of Erwin & Sparke that this is a stellar nuclear ring instead of an
inner disk.

4. 2002ApJS..143...73E
Re:NGC 4643
NGC 4643.---SB0: Bright, elliptical bulge threaded along
its major axis by a long, prominent bar. Bulge/bar is
embedded in a faint, smooth, featureless disk.

5. 2000ApJS..129...93F
Re:NGC 4643
NGC 4643. - No compact radio structure was detected on the
untapered or the tapered maps. NVSS also did not detect this source.
However, we have detected several very weak sources (~ 1 mJy) on the
tapered maps, some of which may be due to weak diffuse disk emission.

6. 2000A&AS..141..385V
Re:NGC 4643
D-22 = NGC 4643. (A,E,G,N) Very faint, disclike feature aligned with the
major axis of this otherwise normal-looking barred spiral, extending to
about three times the optical radius of the inner galaxy. Has a
LINER-type optical spectrum (Boulesteix et al. 1988; Ho et al. 1997;
Keel 1983). Only nuclear line emission was found in the H{alpha} imaging
by Pogge & Eskridge (1993) and only very faint, patchy circumnuclear
H{alpha} emission by Pogge (1989). Optical and near-infrared imaging
(Ohta et al. 1990; Shaw et al. 1995) suggest the presence of secondary,
nuclear bar. A projected maximum stellar rotation velocity of 90 km s^-1^
was derived from long-slit spectroscapy at 4 position angles by Bettoni
& Galletta (1997). The Green Bank H I line profile is centered at a
250 km s^-1^ lower radial velocity than the optical redshift of the PRG
and the Nancay and Effelsberg H I velocity, and the Green Bank profile
width (140 km s^-1^) is two times narrower. According to Paper I, the
Green Bank detection is "probably associated with a small companion
galaxy of unknown redshift at 20' distance, which nevertheless is a very
gas-poor system (M_HI_/LB = 0.02 M_sun_/ L_sun,B_)". No other galaxies
were found in the Nancay search area.

7. 1994CAG1..B...0000S
Re:NGC 4643
Hubble Atlas, p. 42
SB0_3_/SBa
(E,L,0)
PH-688-S
Feb 9/10, 1954
103aO + WG2
30 min
NGC 4643 is later in the SBa progression than the first three
smooth-armed SBa galaxies on the preceding page. Although the spiral
pattern is of very low surface brightness, the thin spiral segments
starting on the edge of the disk upon which the bar stops are definite
and show evidence of recent star formation. The knots are presumed to
be incipient HII regions.

8. 1994CAG1..B...0000S
Re:NGC 4643
Hubble Atlas, p. 42
SB0_3_/SBa
(E,L,0)
PH-688-S
Feb 9/10, 1954
103aO + Wr2
30 min
NGC 4643 is nearly identical to NGC 4608
at the left below. The description there applies to
NGC 4643 as well.

9. 1994AJ....107...99R
Re:NGC 4643
D-22 = NGC 4643. A very faint, disk-like feature is aligned with the
major axis and extending to three times the optical diameter of this
otherwise normal-looking barred spiral (cf. PRC). The GB 140' detection
is at a radial velocity more than 300 km s^-1^ lower than the quoted
optical velocity. Since NED lists no optical companions within 10', and
one small galaxy of unknown redshift within 20', most of the
1.1 x 10^8^ M_sun_ of H I seen by the GB 140' is probably associated with
this system. Nevertheless, its gas-to-light ratio of about M_HI_/L_B_ =
0.02 is smaller than average for an SB0/a (Giovanelli & Haynes 1988).

10. 1976RC2...C...0000d
Re:NGC 4643
Photometry:
Bull. A.A.S., 5, 349, 1973.
Photometry (7 Color):
Izv. Spets. Ast. Obs., 6, 27, 1974.
Spectrophotometry:
Observatory, 88, 239, 1968.

11. 1973UGC...C...0000N
Re:UGC 07895
SB(rs)0/a (de Vaucouleurs)

12. 1964RC1...C...0000d
Re:NGC 4643
Very bright diffuse nucleus in a strong narrow bar: 1.65 arcmin x 0.25 arcmin.
Weak (r): 1.65 arcmin x 1.55 arcmin. Lens: 1.8 arcmin x 1.7 arcmin.
surrounded by continuous dark rings and traces of filamentary arms.
Lund 9, Heidelberg Veroff. Vol. 9, 1926 and HA 88, 2 (after Helwan) dimensions
are for the bright part only.
Photometry:
M.N.R.A.S., 94, 806, 1934.
Spectrum:
I.A.U. Symp., No. 5, 1958 = Lick Contr. II, 81, 1958.

13. 1961Hubbl.B...0000S
Re:NGC 4643
SB03/SBa(r)
PH-688-S
Feb. 9/10, 1955
103aO + WG2
30 min
Enlarged 3.5X
The nucleus, lens, bar, and inner envelope of this galaxy
are of the SB03 type. There is very faint but definite spiral
structure outside the inner envelope, however. There
appears to be a circular dust ring which makes a complete
revolution touching the ends of the bar. The thin spiral
pattern outside the dust ring winds outward through a
tenuous outer envelope. A few knots in the spiral arms
show the beginning of resolution into what are probably
HII regions.

14. 1956AJ.....61...97H
Re:NGC 4643
HMS Note No. 147
Slit on bright central bar.


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