Date and Time of the Query: 2019-06-17 T01:54:09 PDT
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Notes for object NGC 3900

6 note(s) found in NED.

1. 2007MNRAS.376.1513N
Re:UGC 06786
A strong stellar H{alpha} absorption feature is present in the central
arcseconds of the optical spectrum of UGC 6786 (NGC 3900); no H{alpha} emission
is detected in the inner parts. Emission is detected in the central parts in the
6583.46-A [N II] line, but the standard procedure of stacking together the
different emission lines in the optical spectrum cannot be used here. Instead,
we analysed the H{alpha} and [N II] lines separately in this case, and combined
the resulting rotation curves afterwards; at positions where emission was
detected in both lines, the average velocity was calculated. The spectrum shown
in the figure in Appendix C was created by replacing the inner part (15 pixels
on either side of the centre) of the H{alpha} spectrum by the corresponding
region of the [N II] line. Thus, it shows the extended H{alpha} emission in the
outer regions, together with the [N II] emission in the nuclear region.
Note that the central emission in the [N II] line is irregular, with broad
line profiles. This may be explained as a result of line-of-sight integration
effects through the inner regions of the massive bulge of UGC 6786 (see Paper
II), but observations at higher spatial resolution and sensitivity are required
to investigate this in more detail. At a radius of 5 arcsec on the approaching
side, a strong emission feature is detected which has a velocity that lies more
than 100 km s^-1^ closer to the systemic velocity than the emission at
smaller radii. It seems unphysical that this emission traces regular rotation of
gas in the plane of the galaxy and we did not include it in the combined
rotation curve.
The outer parts of the H I disc are distorted as well, with two large spiral
arms extending from the symmetric inner disc. It is impossible to determine the
exact orientation of the gas in these arms and no tilted rings were fit outside
a radius of 240 arcsec. The residual velocity field shows a peculiar m = 5
harmonic component in the azimuthal direction. According to the results of
Schoenmakers et al. (1997), this implies an m = 6 perturbation in the
gravitational potential of this galaxy. No obvious source of such a perturbation
can be identified in the visible matter in this galaxy, so the perturbation, if
real, must be caused by the dark matter halo.
Since UGC 6786 does not have a regular exponential stellar disc, no disc
scalelengths are indicated in the figures in Appendix C.

2. 2005A&A...442..137N
Re:UGC 06786
The gas in the inner parts of UGC 6786 (NGC 3900) follows the light distribution
of the optical image. Most of the gas in the outer parts is concentrated in two
diffuse spiral arms which seem to be warped with respect to the inner parts.

3. 2002AJ....123..159C
Re:NGC 3900
Center likely reddened by dust; red (dust) patches surround center

4. 2001AJ....122..653R
Re:NGC 3900
NGC 3900: The archival V image shows patchy dust, but this is not
present in the NIR image. As seen from the residual image and the radial
variation of the B_4_ parameter, there is a nuclear disk within the inner
0.8". The profile of NGC 3900 would probably be better modeled by multiple
components. To achieve an acceptable fit with the Nuker law, we restricted
the fit to r <= 3".

5. 1973UGC...C...0000N
Re:UGC 06786
SA(r)0+ (de Vaucouleurs)
Bright smooth (r)

6. 1964RC1...C...0000d
Re:NGC 3900
Bright nucleus. (r): 1.2 arcmin x 0.5 arcmin. Dark lane on one side.
Possibly an SAB(r)0+

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