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Notes for object NGC 3521

17 note(s) found in NED.


1. 2012ApJ...754...67F
Re:NGC 3521
NGC 3521 .SXT4..-The latest Hubble type with classical bulge in our sample. In
HST F606W the classical bulge morphology stands in strong contrast to the strong
outer disk spiral structure with a sudden transition of those two morphologies
at r ~=10". The rotation curve forms a shelf at about 3" but rises again
slightly toward larger radii and starts to flatten out at 16". The velocity
dispersion reaches a local maximum of ~=115 km s^-1^ at the bulge radius (r_b_ =
10.8") but then strongly drops with decreasing radius and reaches a local
minimum of ~=100 km s^-1^ at 4". Further inward the dispersion is centrally
peaked. Outside the bulge region the dispersion shows another local maximum
around 40" which also corresponds to a slight secondary shelf on the rotational
velocity. The h_3_ moments are anti-correlated with velocity and form a shelf at
about the same radii where the inner shelf in rotational velocity is seen.
Outside the bulge, h_3_ becomes rather strong (up to 0.22) and is accompanied by
strong, positive h_4_ moments of up to 0.15. These large moments are a
consequence of the double-peak structure of the LOSVDs which has been previously
reported by Zeilinger et al. (2001) caused by a secondary kinematic component
(see Section 5.7). The minor axis velocity dispersion profile does not show the
strong local minima that the major axis profile shows but is similarly disturbed
outside the bulge.

2. 2011AJ....141...23B
Re:NGC 3521
A.12. NGC 3521
Another distant galaxy in our sample, NGC 3521 is a spiral
galaxy with a prominent bar located at a distance of 10.7 Mpc
and viewed almost edge-on (i = 72.7^deg^). The analysis of
NGC 3521 revealed 13 holes in the HI distribution. The small
number of holes detected and the lack of type 3 holes can be
attributed to the large distance of this galaxy as well as its
high inclination. All of the holes detected were consequently
classified as supershells.

3. 2008AJ....136.2648D
Re:NGC 3521
4.10. NGC 3521 was previously observed in H I by Casertano & van Gorkom (1991).
Its rotation curve was presented as one of the first cases where a genuinely
declining H I rotation curve was found in a spiral galaxy. We compare our curve
with the Casertano & van Gorkom (1991) curve in Figure 13. The agreement is not
perfect; the literature curve underestimates the rotation velocity in the inner
parts whereas our curve does not show the steep drop in the outer parts.
Unfortunately, Casertano & van Gorkom (1991) do not list the values they assume
for i and P.A., which precludes a more detailed comparison. The high
inclinations and resulting insensitivity of the rotation velocities to the exact
inclination values, make it unlikely that the difference is a pure inclination
issue. For example, a change in i of 5^deg^, starting from an initial value of i
= 75^deg^, only amounts to a change of some 2% or ~4 km s^-1^, not the ~30 km
s^-1^ that is needed to bring the Casertano & van Gorkom (1991) in agreement
with ours. In summary, even though we find rotation velocities in the outer
parts that are lower than in the inner parts, we do not find evidence for the
steep drop, nor for the negative gradient in outer velocities as presented in
Casertano & van Gorkom (1991).

4. 2008AJ....136.2648D
Re:NGC 3521
6.8. NGC 3521 The surface brightness profiles of NGC 3521 are shown in Figure
39. The 2MASS J, H, and K profiles can be traced out to ~250", and the 3.6 {mu}m
profile out to the edge of the H i disk. The photometric analysis is made
difficult by the faint stellar halo surrounding the main disk. It is
significantly extended along the minor axis, which, through the ellipse
integration used, results in a flattening of the surface brightness profile at
larger radii. For this reason, results from the stellar decomposition are more
uncertain than for other galaxies in the current sample. We treat the stellar
disk as a single component. A clear color gradient is present. The value for
{GAMMA}^3.6^_*_ changes from ~1 in the center to ~0.6 in the outer parts. Beyond
the last reliable 2MASS radius, we assume a constant {GAMMA}^3.6^_*_ = 0.6. The
rotation curve models are presented in Figure 40. Neither model fits perfectly,
but both give reasonable {GAMMA}^3.6^_*_ ratios. Assuming the fixed
{GAMMA}^3.6^_*_ values, it follows that the dynamics of NGC 3521 are dominated
by its stars.

5. 2006MNRAS.366.1265B
Re:NGC 3521
The declining H I rotation curve of this galaxy allowed Casertano & van Gorkom
(1991) to call for the end of the "disc-halo conspiracy". Though not visible in
H{alpha}, the rotation curve starts to decline within a radius of 22 kpc, and
the H{alpha} data stop at 13 kpc.

6. 2006ApJS..165..307M
Re:NGC 3521
HIPASS J1105-00 (NGC 3521).This moderately inclined bulge-dominated Sb galaxy
has an HSB nucleus that is saturated in R and masked out in our net H{alpha}
image. Hence, our F_H{alpha} and S_e_(H{alpha}) measurements are underestimated.
However, examination of the NB images suggests that nucleus does not
significantly contribute to the total F_H{alpha}_. There is an apparent H{alpha}
ring at r ~ 25", while the disk beyond that to r = 116" is well covered by H II
regions and DIG.

7. 2003ApJ...582..190D
Re:NGC 3521
NGC 3521.The ellipticity of this galaxy is so low that it might be
questionable whether it is in fact a barred galaxy. But first we note
that this galaxy is classified as a barred galaxy in the RC3 catalog
(Table 1). However, the bar is not easy to distinguish. This is partly
because of the low ellipticity of the bar but also because of the high
inclination of the galaxy (62^deg^). We found evidence for the bar in the
K-band photometry and also in the intensity profile along the major
axis of the galaxy. Also, Zeilinger et al. (2001) find evidence for
the bar both in their R-band photometry and in the stellar kinematics
derived from the long-slit spectra obtained along different axes in
the galaxy. This leads us to believe that there is a rather round bar
in this galaxy. The bulge is very bright and very large; it is over
three-fourths the size of the bar, and this indicates that it may also
be very massive.

8. 2002AJ....124..675C
Re:UGC 06150
Two NVSS components are needed to approximate the radio emission from
this large spiral galaxy, not including the background double radio
source to the southwest.

9. 2002A&A...388...50F
Re:NGC 3521
The PV diagram of this intermediate-type spiral has been recently
measured by Sofue et al. (1998) from the H{alpha} and the
[N II] {lambda}6583 emission lines. They interpreted the central
component observed in the [N II]{;ambda}6583 line as an indication
of the presence of a fast rotating gaseous disk in the nucleus.
We suggest that this feature, which is clearly visible also in
the PV diagram we derived from the [O III]{lambda}5007 emission
line, results from the increase of the line flux rather than the
velocity gradient. Morever, the velocity dispersion does not
change with radius. Therefore it is Type III diagram.

10. 1998PASJ...50..427S
Re:NGC 3521
NGC 3521: This highly tilted Sbc galaxy shows a strong and broad
H{alpha} absorption around the nucleus. The absorption feature is as
wide as ~ 20 A (~ 1000 km s^-1^), and is extended for about 10", but
shows little rotation. On the other hand, the [N II] line suffers from
no absorption, and can be better used for tracing the kinematics in the
PV diagram. The nuclear component in the [N II] line indicates a rapidly
rising rotation curve of the nuclear disk. The disk part shows a nearly
flat rotation in both the H{alpha} and [N II] lines.
For its very slow rotation and extended feature, the H{alpha}
absorption component is most likely caused by a stellar absorption line
of the central bulge stars. Such a broad absorption line is well known
for A type stars as the damped wing in the Balmar lines due to Stark
broadening. In order that such a bright A type star cluster be present,
a large-scale starburst may have occurred within the last 10^9^ years
(e.g., Dressler, Gunn 1983).

11. 1997AJ....114.2428S
Re:NGC 3521
NGC 3521: The inner rotation velocity increases steeply, and attains a small
and sharp central peak at 10" (520 pc) of 210 km s^-1^, followed by a dip at
20" (1 kpc). It then increases slowly until a broad maximum at 1.5' (4.7 kpc).
However, the very center shows very weak emission, indicating either little CO
gas in the center, or a very high velocity dispersion. The outer H I RC
gradually decreases until the edge.

12. 1996ApJ...473..117S
Re:NGC 3521
NGC 3521 and 2683.--These are given by Casertano & van Gorkom (1991) as
examples of galaxies with declining rotation curves. The contribution of the
gas to the Newtonian rotation curve is not shown here because the mean radial
distribution of the gas is not given in this reference; in any case, the total
gas mass, estimated from global 21 cm line profiles (Table 1), is less than
10% of the fitted disk mass (Table 3) in both cases. The photometry by Kent
(1985) includes decompositions into exponential disks and r^1/4^ law bulges.
Here the models, rather than the detailed light distributions, are used to
determine the Newtonian rotation curves. The observed rotation curves are not
ideal for estimating the true run of circular velocity. In neither case is the
rotation curve determined from a full two-dimensional radial velocity field.
In NGC 3521, the distribution of H I is asymmetric, extending 20% farther on
one side than on the other, and the velocity structure is asymmetric; NGC 2683
is nearly edge-on. Thus these galaxies fail in several respects to satisfy the
selection criteria of BBS. Nonetheless, the rotation-curve fits demonstrate
that MOND is quite capable of reproducing declining rotation curves if the
mass distribution is sufficiently centrally concentrated, a point made by
Milgrom in his original paper (Milgrom 1983). In NGC 3521, the abrupt decline
in rotational velocity between 20 and 28 kpc could he, if confirmed,
problematic for MOND, although it would also be problematic for Newtonian
dynamics since the decline is steeper than Keplerian.

13. 1996ApJ...469L..45T
Re:NGC 3521
NGC 3521.--The residual map of the Sbc galaxy NGC 3521 (d = 7.2 Mpc) shows a
tightly wound two-arm pattern (Fig. 3b). The eastern arm is long and
continuous, extending over 180^deg^ in azimuth to 3.5 kpc (0.3 R_25_) while the
western arm appears to split in two, leaving a continuous spiral arm over
~130^deg^ of azimuth to a radius of 2.4 kpc. K' emission from the central
region is extremely strong and is offset from the centroid of the disk by ~2"
to the west.

14. 1994CAG1..B...0000S
Re:NGC 3521
Hubble Atlas, p. 15
Sbc(s)II
CD-1748-S
Jan 12/13, 1981
103aO + GG385
45 min
The central 1' (diameter) region of NGC 3521
is a high-surface-brightness disk having
spiral dust lanes but no luminous arms.
Luminous arm fragments begin at the edge of this
inner disk. They are interspersed with associated
dust lanes and define the outer MAS pattern,
which is of the NGC 2841-NGC 488 type.
The moderately short exposure print in the
Hubble Atlas, made from an original Mount Wilson
100-inch plate, shows the bright central disk
and a hint of a luminosity distribution above the
plane, centered on this central region. In the
Hubble Atlas print this appears as an overlay of
luminosity in silhouette against the far side of the
disk. In the print here from a deeper Las Campanas
plate, this "cylinder" of light perpendicular
to the plane, concentric with the center,
is more evident. It can be traced in height until
it appears even beyond the image of the disk on
the far side, showing that the distribution is, in
fact, perpendicular to the plane.
The disk is resolved into individual stars.
The largest HII regions have core-plus-halo
diameters of 4", which, with a redshift distance
of 12.5 Mpc based on the redshift of v_o = 627 km/s,
is a linear diameter of 240 psc, consistent
with the calibration elsewhere (Sandage and
Tammann 1974a).

15. 1973UGC...C...0000N
Re:UGC 06150
SAB(rs)bc (de Vaucouleurs), Sb- (Holmberg)
Texture indicates Sb+, but color Sb-

16. 1964RC1...C...0000d
Re:NGC 3521
Very small, very bright nucleus in a complex hexagonal lens: 4.2 arcmin x
1.4 arcmin. Many filamentary, knotty arms and dark lanes. Faint,
filamentary outer arms.
HA 88, 2 major dimensions are for the bright part only.

17. 1961Hubbl.B...0000S
Re:NGC 3521
Sb
H-1019-H
Jan. 11/12, 1929
E40
60 min
Enlarged 4.5X
This galaxy is in the sequence of NGC 2841-type systems
described in the NGC 5055 legend (left). The arms in NGC 3521
can be traced to within 6 sec of arc (radius) from the
center (about 2 mm on the illustration). The segments of
dust arms and luminous arcs, which constitute the
multiple-arm spiral pattern, are similar to those of NGC 2841
and NGC 5055. Individual arms are impossible to trace because
only discontinuous segments exist.


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