Search for post-starburst (E+A) galaxies in the cluster Abell 3266

Author

Zhongyu Zhang

Abstract

"The objective of this work is to use spectroscopic techniques to further the understanding of the dynamical state of the galaxy cluster Abell 3266. This is a very rich cluster in the southern skies that has been extensively studied by many groups. The cluster shows evidence of a merger of substructure in its midst, but the geometry, dynamics, and age of this merger remain uncertain. Low resolution, fiber spectra of galaxies in Abell 3266 were analyzed and searched for "E+A" (post-starburst) galaxies, from which we selected two candidate "E+A" galaxies for follow-up high-resolution spectroscopy. The 2 candidate galaxies are confirmed as "E +A" galaxies with high-resolution, slit spectra. The ages of these "E+A" galaxies (i.e. time since their starburst occurred) are determined with the method developed by Leonardi & Rose (1996). We find that both galaxies had a major starburst in the past, but they occurred at significantly different epochs. If the starbursts are related to the recent merger history of Abell 3266, instead of being just isolated events, they would indicate that there may have been more than one merger in this cluster in the past 3 Gyr or so. This might explain the rather disparate conclusions that have been obtained in the past about the merger history of this cluster. To compare with other nearby clusters, "E+A" galaxies were also searched for among nearly 2400 galaxies in 26 clusters fields. Only 4 candidates are found. This result is consistent with the general observational fact that there are substantially fewer spectroscopically disturbed galaxies in nearby clusters than in distant clusters. The result is also in quantitative agreement with the findings in the larger, more homogeneous Las Campanas Redshift Survey, confirming the reliability of our identification in Abell 3266. The impact of these statistical analyses on the understanding of galaxy evolution in cluster environment is also discussed"--Abstract, page iii.

Advisor(s)

Flores, Ricardo
Schmitt, John L.

Committee Member(s)

Wilking, Bruce
Alexander, Ralph William, Jr.
Whitefield, Philip D.

Department(s)

Physics

Degree Name

Ph. D. in Physics

Publisher

University of Missouri--Rolla

Publication Date

2003

Pagination

ix, 72 pages

Note about bibliography

Includes bibliographical references (pages 66-71).

Rights

© 2003 Zhongyu Zhang, All rights reserved.

Document Type

Dissertation - Citation

File Type

text

Language

English

Subject Headings

Galaxies -- ClustersAstronomyStarbursts

Thesis Number

T 8343

Print OCLC #

54761013

Recommended Citation

Zhang, Zhongyu, "Search for post-starburst (E+A) galaxies in the cluster Abell 3266" (2003). Doctoral Dissertations. 72.
https://scholarsmine.mst.edu/doctoral_dissertations/72