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Title: Weakly barred early-type ringed galaxies. II. The double-ringed S0(+) galaxy NGC 7187

Abstract

CCD surface photometry of the southern ringed S0(+) galaxy NGC 7187, a particularly good example of a system with two bright clear rings with significantly different apparent shapes and almost no sign of a bar, is presented. The galaxy has below average luminosity and the rings are small compared to those observed in more typical (R)SB(r) type galaxies, even though the ratio of their sizes is similar to those in such galaxies. Bulge isophotes reveal the existence of two nearly orthogonal ovals, one having the same shape and position angle as isophotes of the outer disk. The central oval shows significant m = 4 deviations from elliptical isophote shapes and could be a nuclear bar. The rings are slightly blue enhancements compared to their surroundings. The mean colors of both rings do not imply exceptionally high star formation at the present time. 44 refs.

Authors:
 [1]
  1. (Texas Univ., Austin (USA) Alabama Univ., Tuscaloosa (USA))
Publication Date:
OSTI Identifier:
6699033
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; (USA); Journal Volume: 354
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; GALAXIES; MORPHOLOGY; GALACTIC EVOLUTION; GRAVITATIONAL INTERACTIONS; LUMINOSITY; PHOTOMETRY; RINGS; SPIRAL CONFIGURATION; BASIC INTERACTIONS; CONFIGURATION; INTERACTIONS; OPTICAL PROPERTIES; PHYSICAL PROPERTIES 640105* -- Astrophysics & Cosmology-- Galaxies

Citation Formats

Buta, R. Weakly barred early-type ringed galaxies. II. The double-ringed S0(+) galaxy NGC 7187. United States: N. p., 1990. Web. doi:10.1086/168705.
Buta, R. Weakly barred early-type ringed galaxies. II. The double-ringed S0(+) galaxy NGC 7187. United States. doi:10.1086/168705.
Buta, R. 1990. "Weakly barred early-type ringed galaxies. II. The double-ringed S0(+) galaxy NGC 7187". United States. doi:10.1086/168705.
@article{osti_6699033,
title = {Weakly barred early-type ringed galaxies. II. The double-ringed S0(+) galaxy NGC 7187},
author = {Buta, R.},
abstractNote = {CCD surface photometry of the southern ringed S0(+) galaxy NGC 7187, a particularly good example of a system with two bright clear rings with significantly different apparent shapes and almost no sign of a bar, is presented. The galaxy has below average luminosity and the rings are small compared to those observed in more typical (R)SB(r) type galaxies, even though the ratio of their sizes is similar to those in such galaxies. Bulge isophotes reveal the existence of two nearly orthogonal ovals, one having the same shape and position angle as isophotes of the outer disk. The central oval shows significant m = 4 deviations from elliptical isophote shapes and could be a nuclear bar. The rings are slightly blue enhancements compared to their surroundings. The mean colors of both rings do not imply exceptionally high star formation at the present time. 44 refs.},
doi = {10.1086/168705},
journal = {Astrophysical Journal; (USA)},
number = ,
volume = 354,
place = {United States},
year = 1990,
month = 5
}
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