Kinematics of the dusty circumnuclear ring in the barred Seyfert galaxy NGC 4151

M. W. Asif, C. G. Mundell, A. Pedlar, S. W. Unger, A. Robinson, B. Vila-Vilaró, J. R. Lewis

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

We present optical and neutral hydrogen observations of the central ∼2 kpc in NGC 4151, and examine the distribution and kinematics of neutral hydrogen in the vicinity of the optical circumnuclear dust 'ellipse'. The V-I colour map, derived from broad-band images obtained using TAURUS II in imaging mode, shows clearly the red arcs which delineate the 11″ × 18″ dust ellipse detected previously. The new, high resolution (∼ 6″ × 5″) HI image reveals two arcs of HI emission, which lie on the inner edges of the main bar and coincide closely with the optical arcs. The peak column densities in the HI arcs, of ∼ 1.8 × 1021 cm-2 and ∼ 0.7 × 1021 cm-2, imply optical extinctions of Av ∼1.16 and 0.45 in the northern and southern arcs respectively, which are comparable with those derived from broad-band imaging. The kinematics of the HI, measured along the two arcs, are presented. The first order circular fit to the velocity curve yields a value of 22±5° for the PA of the line of nodes, which agrees well with that of the galaxy. If the HI is associated with the optical ellipse, the PA of the spatial major axis of the ellipse (∼48°) is offset from its kinematic major axis (∼22°), providing evidence of non-circular orbits and suggesting that ring is not an inclined circular disk, but is intrinsically elliptical and lies in the plane of the galaxy.

Original languageEnglish
Pages (from-to)466-470
Number of pages5
JournalAstronomy and Astrophysics
Volume333
Issue number2
Publication statusPublished - May 1998

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barred galaxies
Seyfert galaxies
ellipse
ellipses
kinematics
arcs
rings
hydrogen
dust
red arcs
galaxies
broadband
extinction
orbits
color
high resolution
curves

Keywords

  • Galaxies: active
  • Individual: NGC 4151
  • Kinematics and dynamics
  • Seyfert

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

Asif, M. W., Mundell, C. G., Pedlar, A., Unger, S. W., Robinson, A., Vila-Vilaró, B., & Lewis, J. R. (1998). Kinematics of the dusty circumnuclear ring in the barred Seyfert galaxy NGC 4151. Astronomy and Astrophysics, 333(2), 466-470.

Kinematics of the dusty circumnuclear ring in the barred Seyfert galaxy NGC 4151. / Asif, M. W.; Mundell, C. G.; Pedlar, A.; Unger, S. W.; Robinson, A.; Vila-Vilaró, B.; Lewis, J. R.

In: Astronomy and Astrophysics, Vol. 333, No. 2, 05.1998, p. 466-470.

Research output: Contribution to journalArticle

Asif, MW, Mundell, CG, Pedlar, A, Unger, SW, Robinson, A, Vila-Vilaró, B & Lewis, JR 1998, 'Kinematics of the dusty circumnuclear ring in the barred Seyfert galaxy NGC 4151', Astronomy and Astrophysics, vol. 333, no. 2, pp. 466-470.
Asif MW, Mundell CG, Pedlar A, Unger SW, Robinson A, Vila-Vilaró B et al. Kinematics of the dusty circumnuclear ring in the barred Seyfert galaxy NGC 4151. Astronomy and Astrophysics. 1998 May;333(2):466-470.
Asif, M. W. ; Mundell, C. G. ; Pedlar, A. ; Unger, S. W. ; Robinson, A. ; Vila-Vilaró, B. ; Lewis, J. R. / Kinematics of the dusty circumnuclear ring in the barred Seyfert galaxy NGC 4151. In: Astronomy and Astrophysics. 1998 ; Vol. 333, No. 2. pp. 466-470.
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