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Date and Time of the Query: 2019-06-19 T03:03:42 PDT
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Notes for object NGC 5296

3 note(s) found in NED.


1. 1995A&AS..110..131R
Re:NGC 5296
NGC 5296: This galaxy is a dwarf S0 companion (M_B_ = -17.5) which shows
outer isophotes (Fig. 14) distinctly elongated towards (and opposite) the
neighboring giant spiral. The much larger and more massive spiral
component might be expected to produce more noticeable effects on its
neighbor than vice versa. Of course, if the analogy with M31 is a
reasonable one, NGC 205 is not strongly disrupted. Evidence of the faint
elongated structure can be seen in the strong twisting of the isophotes
shown in Fig. 3.2. The elongation suggests that the two galaxies are a
physical pair and that the disk/halo structure of the S0 companion has
been tidally distorted.
The a4/a parameter indicates that the isophotal shape is elliptical
within 0.5%. The profile has been interpolated with a classical bulge +
disk model and the results are reported in Table 7 and plotted in Fig.
20. In the same figure we also plot an attempt to fit the galaxy profile
with a truncated disk. The fitting improved in the central part of the
galaxy where a further component is visible in the residual map of the
classical fitting. This is probably a lens-like structure which has been
observed in the prototype S0 NGC 1553 (Freeman 1975). In this sense the
decomposition of the luminosity profile is unsatisfactory. A similar, but
fainter, structure is also visible in NGC 5481.
The S0 companion shows emission in a central 10 arcsec region as
indicated in Figs. 1, 12. There is clear evidence for rotation (Fig. 1)
({DELTA}V >= 100 km s^-1^) in this gas. We measure a high central stellar
velocity dispersion (Table 3), considerably larger than the weighted
value measured by Bonfanti (1994) where {sigma} = 144 +/- 47 km s^-1^. A
central value ( ~200 pc at our resolution) of nearly 300 km s^-1^ for a
dwarf galaxy places NGC 5296 off of a Fundamental Plane computed for
elliptical galaxies as discussed in Bender et al. (1992). In fact, since
our galaxy can be included in the Hot Dwarf class, following the
classification given by the previous authors, our value of the central
velocity dispersion has to be compared with a typical one of ~100 km
s^-1^. A corresponding luminosity spike is not seen, but the seeing
characteristics of our images preclude any definite conclusion. It is not
then clear to what this excess in velocity dispersion could be related.
There are at least three lines of evidence that may point toward a
cross fuelling origin for this gas. 1) Figure 1 shows evidence for a
kinematic decoupling between the stars and gas. The gas is systematically
displaced toward lower velocity even at the barycenter of the starlight
(although this single point is not statistically significant). In
addition, the slope of the rotation curves for the stars and gas appear
to be different. 2) No evidence for faint structure was found when a
smooth model of the galaxy was subtracted from our original images.
However an H{alpha} image (Sharp 1988) shows a bright knot adjacent to
the nucleus. A condensation of this kind is more unusual and less
consistent with the idea that the gas originated from internal stellar
mass loss. The physical conditions of the gas as inferred from the
(N II]/H{alpha} ratio (Fig. 12) suggest HII region-like emission. 3)
Figure 14 shows that the (B - V) radial profile of NGC 5296 is bluer in
the center, differently from the spiral which shows the expected increase
in (B-V) as one approaches the nucleus. A (B - V) color excess of this
kind could be interpreted as evidence for a young stellar population in
the center. This could be evidence for (periodic) episodes of star
formation fuelled by the spiral. Population synthesis studies of E+S
pairs in progress (De Mello Rabaca 1994 in preparation) will test this
interpretation.

2. 1976RC2...C...0000d
Re:NGC 5296
= Kara[72] 394
Interacting (?) pair with NGC 5297 at 1.6 arcmin.

3. 1964RC1...C...0000d
Re:NGC 5296
Small, bright nucleus.
Heidelberg Veroff. Vol. 9, 1926 dimensions (0.25 arcmin x 0.25 arcmin)
rejected, nucleus only.
Interacting? pair with NGC 5297 at 1.6 arcmin.


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