Studies of Ir II galaxies. I. NGC 4753 and NGC 5273.
Abstract
Summary. Photometric observations of NGC 5273 and spectroscopic and photometric observations of NGC 4753 demonstrate that the visible light from these dusty galaxies originates primarily from late-type stars. Eleven-color photometry shows NGC 5273 to have a stellar population typical of a normal elliptical galaxy of low luminosity (My - 17.7). The spectral abnormalities mentioned by Markarian are not apparent in the photometry Spectroscopy and photometry of NGC 4753 do not provide an unambiguous interpretation of this peculiar galaxy. Interior to a radius of 40 arc seconds, the object is rotating as a solid body, and the masses determined for this region lie in the range 0.9 to 4.4 x IO M0. Although one reasonable interpretation of the observational evidence implies that NGC 4753 has a population and luminosity identical to those of a normal elliptical with My = - 19.7, other interpretations cannot be entirely ruled out. Key words: galaxies - irregular galaxies - stellar populations - rotation curves
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- November 1973
- Bibcode:
- 1973A&A....29...77C