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Date and Time of the Query: 2019-08-21 T22:09:22 PDT
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Notes for object IC 2531

10 note(s) found in NED.


1. 2005MNRAS.358..481K
Re:ESO 435- G 025
ESO 435-G25. As a result of a deficiency of gas in the inner parts the circular
velocities are unknown at R[IMAGE] 50 arcsec. Therefore, models were constructed
for two extreme cases, taking a solid-body and a flat rotation curve in this
region (down to R= 0). The best-fitting model parameters found for the two cases
are consistent to within the errors (the inner parts are largely excluded from
the fits). The solid-body rotation is adopted here because it better matches the
stellar rotation at radii smaller than the inner fitting boundary. The h_3_ and
h_4_ parameters are also reproduced rather well. These results, obtained using
the luminosity distribution according to Xilouris et al. (1999), are consistent
with those obtained using the distribution derived in KKG (not shown).

2. 2004MNRAS.352..787K
Re:ESO 435- G 025
ESO 435-G25. The XV diagram is highly asymmetric. The residual XV
diagrams show a lack of H I at R <~ 50 arcsec. Receding side, the upturn
in the velocities at large radii is associated with the (projected) end
of the curved ridge dominating the XV diagram on this side. Approaching
side, the XV fit velocities are slightly higher than those derived from
the envelope. Interestingly, the velocities in the extension (R > 180
arcsec) are higher than those found with the envelope-tracing method,
but consistent with a flat rotation curve. The extension is similar in
appearance to the well-studied southern extension of NGC 891 (Rupen
1991).

3. 2004MNRAS.352..787K
Re:ESO 435- G 025
ESO 435-G25. The XV diagram is highly asymmetric. The residual XV
diagrams show a lack of H I at R <~ 50 arcsec. Receding side, the upturn
in the velocities at large radii is associated with the (projected) end
of the curved ridge dominating the XV diagram on this side. Approaching
side, the XV fit velocities are slightly higher than those derived from
the envelope. Interestingly, the velocities in the extension (R > 180
arcsec) are higher than those found with the envelope-tracing method,
but consistent with a flat rotation curve. The extension is similar in
appearance to the well-studied southern extension of NGC 891 (Rupen
1991).

4. 2004MNRAS.352..768K
Re:ESO 435- G 025
ESO 435-G25. The H I in this large Sc spiral, which has a peanut-shaped
bulge, displays rich structure in its distribution and kinematics.
First, the H I, like the stars, extends to larger projected radii on the
approaching side. Secondly, there is a moderate warping of the H I on
both sides. On the approaching side this warp is also observed in the
optical. On that side the rotation curve is approximately flat until it
shows a drop of approximately 20 km s^-1^ coinciding roughly with the
onset of the warp (R ~ 200 arcsec). On the receding side the warping
appears to be smaller. On this side the XV diagram is dominated by a
curved high-density ridge. Inspection of the data cube at full
resolution shows that this ridge is actually a superposition of multiple
linear features (rings). The extreme-velocity envelope at the receding
side is slowly rising from R= 50 up to 160 arcsec and shows a remarkable
upturn in the outskirts, reaching velocities higher than on the
approaching side. Finally, the data hint at a vertical extension in the
central region. Deeper observations are needed to confirm this.

5. 2004MNRAS.352..768K
Re:ESO 435- G 025
ESO 435-G25. The optical counterpart of companion A at a projected
distance of 12 arcmin (12 disc scalelengths) has an irregular appearance
on the Digital Sky Survey (DSS). Companion B, at 14 arcmin (14 disc
scalelengths), has only one-tenth of the H I mass of companion A and is
barely visible on the DSS. Given their small velocity differences with
the systemic velocity of ESO 435-G25, both companions are probably
satellites (both are outside the optical images of de Grijs 1998).

6. 2004MNRAS.351.1247K
Re:ESO 435- G 025
ESO 435-G25. A small plateau is present in the velocity curve at 10
arcsec. The velocity dispersion shows a rather steep drop at small radii
followed by a much more gradual decline starting at ~20 arcsec. The h_3_
curve shows a conspicuous signature. This signature is also seen in at
least three other galaxies and will be discussed in Section 5. Note that
the h_3_ goes through the origin, suggesting that template mismatch is
not a problem.

7. 2000MNRAS.313..800D
Re:ESO 435- G 025
ESO 435-G25 consistently shows bluer colours with increasing z height,
although we cannot determine whether we are observing the intrinsic
galaxy colours or the effects of residual dust extinction at
progressively higher positions in the disc. The galaxy shows a very
prominent dust lane, extending from the galactic centre to the edge of
the disc, as well as into the higher stellar layers, as is evidenced by
dust features that can be traced up to a few scaleheights (Fig. 2f;
T = 5.0).

8. 1985SGC...C...0000C
Re:IC 2531
Plate 1321
Similar to NGC 4565 with flattened bulge.

9. 1982ESOU..C...0000L
Re:ESO 095741-2922.5
=ESO 435- G 25
absorption lane
in cluster

10. 1974UGCA..C...0000N
Re:UGCA 191
UGCA 191:
= IC 2531


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