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

Journal Article · · Astrophysical Journal; (USA)
DOI:https://doi.org/10.1086/168705· OSTI ID:6699033
 [1]
  1. Texas Univ., Austin (USA) Alabama Univ., Tuscaloosa (USA)

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.

OSTI ID:
6699033
Journal Information:
Astrophysical Journal; (USA), Vol. 354; ISSN 0004-637X
Country of Publication:
United States
Language:
English