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Title: Intermediate-age globular clusters in four galaxy merger remnants

Abstract

We present the results of combining Hubble Space Telescope optical photometry with ground-based K{sub s} -band photometry from the Gemini imagers NIRI and FLAMINGOS-I to study the globular cluster (GC) populations in four early-type galaxies that are candidate remnants of recent mergers (NGC 1700, NGC 2865, NGC 4382, and NGC 7727). These galaxies were chosen based on their blue colors and fine structure, such as shells and ripples that are indicative of past interactions. We fit the combined VIK{sub s} GC data with simple toy models of mixed cluster populations that contain three subpopulations of different age and metallicity. The fits, done via chi-squared mapping of the parameter space, yield clear evidence for the presence of intermediate-age clusters in each galaxy. We find that the ages of ∼1-2 Gyr for these GC subpopulations are consistent with the previously estimated merger ages for the host galaxies.

Authors:
 [1];  [2];  [3];  [4];  [5]
  1. Giant Magellan Telescope Organization, 251 South Lake Avenue, Pasadena, CA 91101 (United States)
  2. Gemini Observatory, Casilla 603, La Serena (Chile)
  3. Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States)
  4. The University of Adelaide, South Australia 5005 (Australia)
  5. Monash University, Clayton, Victoria 3800 (Australia)
Publication Date:
OSTI Identifier:
22365484
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 790; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; COLOR; FINE STRUCTURE; GALAXIES; INTERACTIONS; K ABSORPTION; METALLICITY; PHOTOMETRY; SPACE; STAR CLUSTERS; TELESCOPES

Citation Formats

Trancho, Gelys, Miller, Bryan W., Schweizer, François, Burdett, Daniel P., and Palamara, David, E-mail: gtrancho@gmto.org. Intermediate-age globular clusters in four galaxy merger remnants. United States: N. p., 2014. Web. doi:10.1088/0004-637X/790/2/122.
Trancho, Gelys, Miller, Bryan W., Schweizer, François, Burdett, Daniel P., & Palamara, David, E-mail: gtrancho@gmto.org. Intermediate-age globular clusters in four galaxy merger remnants. United States. doi:10.1088/0004-637X/790/2/122.
Trancho, Gelys, Miller, Bryan W., Schweizer, François, Burdett, Daniel P., and Palamara, David, E-mail: gtrancho@gmto.org. Fri . "Intermediate-age globular clusters in four galaxy merger remnants". United States. doi:10.1088/0004-637X/790/2/122.
@article{osti_22365484,
title = {Intermediate-age globular clusters in four galaxy merger remnants},
author = {Trancho, Gelys and Miller, Bryan W. and Schweizer, François and Burdett, Daniel P. and Palamara, David, E-mail: gtrancho@gmto.org},
abstractNote = {We present the results of combining Hubble Space Telescope optical photometry with ground-based K{sub s} -band photometry from the Gemini imagers NIRI and FLAMINGOS-I to study the globular cluster (GC) populations in four early-type galaxies that are candidate remnants of recent mergers (NGC 1700, NGC 2865, NGC 4382, and NGC 7727). These galaxies were chosen based on their blue colors and fine structure, such as shells and ripples that are indicative of past interactions. We fit the combined VIK{sub s} GC data with simple toy models of mixed cluster populations that contain three subpopulations of different age and metallicity. The fits, done via chi-squared mapping of the parameter space, yield clear evidence for the presence of intermediate-age clusters in each galaxy. We find that the ages of ∼1-2 Gyr for these GC subpopulations are consistent with the previously estimated merger ages for the host galaxies.},
doi = {10.1088/0004-637X/790/2/122},
journal = {Astrophysical Journal},
number = 2,
volume = 790,
place = {United States},
year = {Fri Aug 01 00:00:00 EDT 2014},
month = {Fri Aug 01 00:00:00 EDT 2014}
}
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