H II region spectroscopy and two dimensional stellar photometry of the barred Seyfert NGC 1566

Beckman, J. E.; Bransgrove, S. G.; Phillips, J. P.
Bibliographical reference

Astronomy and Astrophysics (ISSN 0004-6361), vol. 157, no. 1, March 1986, p. 49-58.

Advertised on:
3
1986
Number of authors
3
IAC number of authors
1
Citations
9
Refereed citations
8
Description
Radial velocities of 14 H II regions were obtained using reticon spectroscopy at H-alpha for the barred spiral NGC 1566. The same spectra also yield N II/H and S II/H ratios, and give values of the electron densities in the range of 10/cu cm. Kinematic and dynamic arguments are used to show that nonradial gas velocities are present, especially outflow at the ends of the bar. Two-dimensional isophotes at high angular resolution (approximately 1 arcsec) are presented in V, R and I. Comparison of M/L ratios based on surface photometry, and based on the inferred rotational dynamics, shows that no missing mass is required in NGC 1566 out to 13.5 kpc from the center. The photometry also shows that the Seyfert nucleus is bluer by over a magnitude than the rest of the central bulge.