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Notes for object NGC 4496A

7 note(s) found in NED.


1. 1999AJ....118.2331V
Re:NGC 4496A
As is the case for SN 1988M in section 3.1.9, the environment of
the SN Ia 1960F is in the deep F555W and F814W images, taken as part of
a project to measure a Cepheid-based distance to SN 1960F (Saha et al.
1996a). Seventeen epochs of F555W imaging and four epochs of F814W
imaging were obtained, each set of images consisting of a pair of 2000 s
exposures. The method for analyzing these images was the same as for the
environment of SN 1979C (see Van Dyk et al. 1999): a model PSF was
produced, stars were located, photometry was performed with DAOPHOT and
ALLSTAR, and the results were averaged over all epochs. Faint stars that
were not found in the individual images were located in summed images,
and the resulting photometry was appended to the results for the
individual images. We performed the photometry over a large area of the
image. Although crowding was severe in some regions, the photometry with
a TinyTim PSF led to satisfactory results. The SN environment on the
summed F555W image is shown in Figure 18. We used the accurate absolute
position for the SN from Porter (1993). The SN occurred in a region
between two spiral arms in NGC 4496A.
We show in Figure 19 the CMD produced by our photometry of the
larger environment around the SN, along with the B94 isochrones,
adjusted for both the reddening (E[V-I] = 0.04) and the distance
modulus(m - M = 31.03) from Saha et al. (1996a), and transformed to
WFPC2 synthetic magnitudes. A large number of populations are revealed
in these deep images, from quite blue to very red, including hot main
sequence stars, red supergiants, and the tip of the red giant branch.
Reddening and crowding are undoubtedly affecting the observed stellar
magnitudes and colors. However, even these images are not deep enough to
see populations with ages >~500 Myr, from which SNe Ia are thought to
arise. After all resolved stars were subtracted away, we estimated a
magnitude and measured a color for the environment, through a 1.5"
aperture centered on the SN position, of m_F555W_ ~ 30.1 mag (the
magnitude of pixels 1 {sigma} above the mean background) and F555W -
F814W ~ 0.6 mag, consistent with a background of late-F stars,
presumably giants with ages >~300 Myr, or possibly fainter, reddened
early-type stars.

2. 1995ApJS...98..477H
Re:NGC 4496A
As discussed extensively in Filippenko et al. (1988), NGC 4496A,B (VV 76)
form an optical, rather than a physical, binary system, with systemic
velocities of cz = 1700 km s^-1^ and 4510 km s^-1^, respectively. The
spectrum of NGC 4496A shown in Figure 67 is not of its nucleus (which was
not observed); it was extracted from an emission-line knot located ~ 19"
south of the nucleus of NGC 4496B (PA = 180 ^deg^; see Filippenko et al.
1988 for details).

3. 1994CAG1..B...0000S
Re:NGC 4496A
VCC 1375
Karachentsev 343 [with NGC 4496B]
SBcIII-IV
CD-2204-S
March 31/April 1, 1982
103aO
50 min
The image of NGC 4496A overlaps that of
NGC 4496B; the centers have an angular
separation of 0.9'. The redshifts listed by
Karachentsev, v_o(4496 A) = 1831 km/s and
v_o(4496B) = 4509 km/s, would put the
companion far in the background. This is curious
because the brightnesses of the numerous
HII-region candidates in both galaxies seem closely
the same, suggesting that the two galaxies are at
nearly the same distance. Additional data are
needed, but an apparent confirmation of the
large redshift of NGC 4496B is given by the
21-cm redshift listed in the VCC of
v_sun_ = 4548 km/s (or v_o = 4391 km/s) attributed
to unpublished observations by Hoffman, Helou,
and Salpeter (1984, private communication).
This may be the same measurement published by
Hoffman et al. (1989), where v_sun_ = 4546 km/s
is listed for NGC 4496B.
Both NGC 4496A and 4496B are listed in
the VCC as non-members of the Virgo Cluster.

4. 1994AJ....108.2128C
Re:PGC 041471
PGC 041471 = NGC 4496A = UGC 7668a. Note improved position in Table 5 of
1994AJ....108.2128C.

5. 1985AJ.....90.1681B
Re:VCC 1375
Two galaxies (with VCC 1376) superposed on each other.
Not recognized by CGCG. DVP did separate the two but give incorrect data.
New estimated magnitudes and diameters.

6. 1976RC2...C...0000d
Re:NGC 4496A
= NGC 4505A
= Holm 415a
in VV 076
in Kara[72] 343
Colliding (?) pair with NGC 4496B at 0.9 arcmin

7. 1964RC1...C...0000d
Re:NGC 4496A
= NGC 4505
= Holm 415a
Brighter of two overlapping systems. Colliding or strongly iteracting pair
with NGC 4496B at 0.9 arcmin. Several filamentary, branching arms. Short,
narrow bar.
Magnitude and colors are for the two components together.
SN 1960
I.A.U. Circ. 1721.
I.A.U. Circ. 1723.
I.A.U. Circ. 1725.
I.A.U. Circ. 1734.
I.A.U. Circ. 1736.
H.A.C. 1480.
C.R. Acad. Sc., Paris, 250, 3952, 1960.
P.A.S.P., 73, 175, 1961.


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