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Date and Time of the Query: 2019-06-17 T02:17:43 PDT
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Notes for object NGC 3976

7 note(s) found in NED.


1. 2008MNRAS.390.1241B
Re:NGC 3976
4.5 NGC 3976 The XMM-Newton spectrum of NGC 3976 is very similar to that of NGC
3486 as it shows no intrinsic absorption, but a hard excess present above the
simple power-law fit allows us to add a heavily absorbed power-law component. A
strongly absorbed transmission component produces an overall better fit,
suggesting that NGC 3976 is also hiding a heavily obscured nucleus beneath its
apparently unabsorbed soft X-ray spectrum. Again, there is also no variability
detected in this observation.

2. 2008MNRAS.390.1241B
Re:NGC 3976
5.3.4 NGC 3976 As with NGC 3486, the hard excess present in this X-ray spectrum
is well fitted by the addition of a reflection component. However, it is also
well fitted by a transmission component. Again, this spectrum is very similar to
the Chandra spectrum of NGC 4501, so we conclude that this source is also
heavily obscured.

3. 2008ApJ...679.1094T
Re:NGC 3976
NGC 3976 is a barred Sb galaxy. It is clearly disturbed in the optical (Fig.
10), exhibiting asymmetric extensions on the northeastern and southwestern sides
of the disk. Although NGC 3976 is not classified as an active galaxy by
Veron-Cetty & Veron (1998), the source used to select the active galaxy sample,
it is classified as a Seyfert 2 with M_B_ = 21.1 in the latest version of this
catalog (Veron-Cetty & Veron 2006). Thus, if NGC 3976 was placed at the same
range of redshifts as the active galaxy sample, it would have been selected as
part of that sample. For internal consistency, however, we retain NGC 3976 in
our control sample. If included in the active galaxy sample, this would make the
conclusions reached in our study only stronger. A relatively faint galaxy at a
comparable optical redshift, PGC 37490, lies ~4.5^'^ to the south of NGC 3976.
We detected NGC 3976, but not PGC 37490. At a spatial resolution of ~20 kpc,
the H I disk of NGC 3976 appears to be asymmetric (Fig. 10). TheH I gas extends
farther out on the northeastern side compared to the southwestern side, giving
the disk a lopsided appearance in H I. In addition, the H I kinematic axis
appears to lie at a different position angle compared with the major axis of the
optical disk. At a spatial resolution of ~10 kpc (also shown in Fig. 10), this
asymmetric appearance appears to be caused in part (but perhaps not wholly) by
the larger H I extension of the northeastern compared with the southwestern
spiral arm.

4. 2001ApJS..133...77H
Re:NGC 3976
NGC 3976 (S2:). - A 0.5 mJy compact core was detected at 6 cm at the
level of 11.5 {sigma} in the full-resolution map and 9 in the tapered map.
Yet, the 20 cm maps show no evidence of any significant signal, suggesting
that the 6 cm source is absorbed at lower frequencies. There are no
previously published radio observations of this galaxy.

5. 1976RC2...C...0000d
Re:NGC 3976
= Holm 305a
Pair with Holm 305b at 4.8 arcmin
Photometry and Isodensitometry:
Ap. J. Suppl., 26, No. 230, 1973.

6. 1973UGC...C...0000N
Re:UGC 06906
SAB(s)b (de Vaucouleurs)
Major diameter includes a faint condensation, which may be a dwarf companion.
11 53.4 +06 58 at 4.6, 243, 0.5 x 0.1, Sb-c, m=15.5

7. 1964RC1...C...0000d
Re:NGC 3976
= Holm 305a
Small, bright, diffuse nucleus. 2 main knotty arms. Poorly resolved.
Pair with faint anonymous galaxy (= Holm 305b) at 4.8 arcmin.


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