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Date and Time of the Query: 2019-03-20 T06:55:41 PDT
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Notes for object NGC 1961

9 note(s) found in NED.


1. 2008MNRAS.388..500E
Re:UGC 03334
UGC 3334 (NGC 1961, Arp 184). NGC 1961 is a very bright and massive distorted
LINER 2 SAB(rs)b galaxy showing highly irregular outer spiral arms and a
pathological disc (Arp 1966). It does not show any nearby companion and no clear
double nucleus indicates a merger in progress. Nevertheless, NGC 1961 is the
central member of the small group of nine galaxies located in the same velocity
interval with a projected separation of 1 Mpc. Two long straight arms tangent to
the north-following side of galaxy point towards an extended H I counterpart
(Shostak et al. 1982). The amplitude of the WHISP velocity field (website) as
well as the width of the H I profile at 20 per cent (~700 km s^-1^ from the
WHISP website and 690 km s^-1^ from Bottinelli et al. 1990) are fully compatible
with the H{alpha} velocity field amplitude. The overall resemblance between
H{alpha} velocity field and H I velocity field is pretty good within the optical
disc taking into account the low spatial resolution in the H I data. However,
H{alpha} kinematics present perturbations all over the disc leading to an
asymmetric and wavy rotation curve. The southern spiral arm and the knotty
regions in the northern arm present unexpected velocities leading to a model of
rotation curve with strong residuals for which it was necessary to constrain the
inclination. Our rotation curve is in reasonable agreement with the rotation
curve along the major-axis from Rubin et al.(1979) but our rotation curve is
almost twice extended on the receding side. Rubin et al.(1979) claimed that NGC
1961, wit its total mass greater than 10^12^ M_{sun}_, was the most massive
spiral known. Due to the uncertainties on the inclination and to waves in the
rotation curve, the maximum rotation velocity (377 +/- 85 km s^-1^) could even
be higher. From their optically derived spectra, they concluded to unexplained
motions within the system. The H{alpha} lines continuously display a double
profile (not resolved by Rubin et al. 1979) from the centre to the outermost
points of the approaching side (as it can be seen in the H{alpha}
position-velocity diagram, the most external velocities reach, respectively,
~3500 and 3720 km s^-1^). The maximum velocity has been chosen as the mean
external velocity. These double profiles in the disc are an additional evidence
for the complex history of this galaxy (merging, interaction, stripping) which
still needs to be modelled taking into account its disturbed and asymmetric H I
distribution and X-ray emission.

2. 2003ApJS..146..353M
Re:NGC 1961
NGC 1961 (TW)
This peculiar galaxy has a multiarm, tightly wound nuclear spiral.
There appear to be a few star clusters to the north of the nucleus,
which may be the far side of the galaxy based on the contrast in the
circumnuclear dust.

3. 2002AJ....124..675C
Re:UGC 03334
LINER

4. 1997ApJS..112..391H
Re:NGC 1961
NGC 1961.--As in NGC 1667, the non-Gaussian (blue) asymmetric wings of the
narrow lines mimic broad H{alpha} (Fig. 8b). Close inspection of the high-S/N
spectrum reveals that the bases of the [S II] lines are somewhat narrower than
those of [N II] and H, whose profiles are nearly identical. If one had forced
all the narrow lines to have the same profile as [S II], one would have
concluded incorrectly that broad H{alpha} is present and that it is displaced
redward of the systemic velocity of the narrow component.

5. 1996ApJS..104..217S
Re:UGC 03334
3.5. UGC 3334
UGC 3334 = NGC 1961 is the central member of the small group of galaxies; there
are some nine galaxies located in the same velocity interval with a projected
separation of 1 Mpc. Its disturbed and asymmetric H I distribution and X-ray
emission suggests the possibility that a gas stripping event is taking place
(Shostak et al. 1982) as a result of interaction with its environment. Although
Br{gamma} emission is not detected in the low-resolution spectrum, there is
evidence of molecular hydrogen emission.

6. 1994CAG1..B...0000S
Re:NGC 1961
Sb(rs)II pec
PH-7549-S
Nov 6/7, 1978
103aO
12 min
The outer spiral arms of NGC 1961 are
highly distorted as if by a close encounter, yet no
companion galaxy is evident. Nor can any
nucleus of such a companion be identified in the
vicinity of the main body. NGC 1961 is the
principal example of a distorted galaxy of the
type cited by advocates of the "merger"
hypothesis where there is no sign of a companion.
The distortion of the arms in NGC 1961 cannot
be ascribed to an encounter or a merger in
progress. Rather, the distortion here appears to
be intrinsic to this apparently isolated galaxy.
Many HII regions exist in the near-side
arms, the largest of which resolve at the 4" level
(for the core). This size is large considering the
large redshift of v_o = 4147 km/s.
Regular dust lanes define thin spiral fragments
in the central parts of the lens.
The absolute magnitude of NGC 1961 at M_B_
= -23.7 is the brightest in the RSA.

7. 1976RC2...C...0000d
Re:NGC 1961
= IC 2133
= Arp 184
Sc with peculiar outer arm and very faint streamers.
HI 21cm: (upper limit)
Observatory, 83, 245, 1963.

8. 1973UGC...C...0000N
Re:UGC 03334
Arp 184
SAB(s)c (de Vaucouleurs), Sb+ (Holmberg)
"2 long straight arms or filaments tangent to north-following side of galaxy"
(Arp)

9. 1964RC1...C...0000d
Re:NGC 1961
= IC 2133
Very small, bright nucleus.
Hexagonal pseudo (r): 0.95 arcmin x 0.8? arcmin,
2 main branch arms with some knots.
Magnitude:
Ap. J., 85, 325, 1937.


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