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Title: EVIDENCE FOR ENRICHMENT BY SUPERNOVAE IN THE GLOBULAR CLUSTER NGC 6273

Abstract

In our recent investigation, we showed that narrowband photometry can be combined with low-resolution spectroscopy to effectively search for globular clusters (GCs) with supernova (SN) enrichments. Here we apply this technique to the metal-poor bulge GC NGC 6273 and find that the red giant branch stars in this GC are clearly divided into two distinct subpopulations with different calcium abundances. The Ca rich subpopulation in this GC is also enhanced in CN and CH, showing a positive correlation between them. This trend is identical to the result we found in M22, suggesting that this might be a ubiquitous nature of GCs more strongly affected by SNe in their chemical evolution. Our results suggest that NGC 6273 was massive enough to retain SN ejecta, which would place this cluster in the growing group of GCs with Galactic building block characteristics, such as ω Centauri and Terzan 5.

Authors:
; ; ;  [1]
  1. Center for Galaxy Evolution Research and Department of Astronomy, Yonsei University, Seoul 03722 (Korea, Republic of)
Publication Date:
OSTI Identifier:
22518688
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 813; 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; CALCIUM; CORRELATIONS; ELEMENT ABUNDANCE; ENRICHMENT; MILKY WAY; PHOTOMETRY; RED GIANT STARS; RESOLUTION; STAR CLUSTERS; STAR EVOLUTION; SUPERNOVAE

Citation Formats

Han, Sang-Il, Lim, Dongwook, Seo, Hyunju, and Lee, Young-Wook, E-mail: ywlee2@yonsei.ac.kr. EVIDENCE FOR ENRICHMENT BY SUPERNOVAE IN THE GLOBULAR CLUSTER NGC 6273. United States: N. p., 2015. Web. doi:10.1088/2041-8205/813/2/L43.
Han, Sang-Il, Lim, Dongwook, Seo, Hyunju, & Lee, Young-Wook, E-mail: ywlee2@yonsei.ac.kr. EVIDENCE FOR ENRICHMENT BY SUPERNOVAE IN THE GLOBULAR CLUSTER NGC 6273. United States. doi:10.1088/2041-8205/813/2/L43.
Han, Sang-Il, Lim, Dongwook, Seo, Hyunju, and Lee, Young-Wook, E-mail: ywlee2@yonsei.ac.kr. Tue . "EVIDENCE FOR ENRICHMENT BY SUPERNOVAE IN THE GLOBULAR CLUSTER NGC 6273". United States. doi:10.1088/2041-8205/813/2/L43.
@article{osti_22518688,
title = {EVIDENCE FOR ENRICHMENT BY SUPERNOVAE IN THE GLOBULAR CLUSTER NGC 6273},
author = {Han, Sang-Il and Lim, Dongwook and Seo, Hyunju and Lee, Young-Wook, E-mail: ywlee2@yonsei.ac.kr},
abstractNote = {In our recent investigation, we showed that narrowband photometry can be combined with low-resolution spectroscopy to effectively search for globular clusters (GCs) with supernova (SN) enrichments. Here we apply this technique to the metal-poor bulge GC NGC 6273 and find that the red giant branch stars in this GC are clearly divided into two distinct subpopulations with different calcium abundances. The Ca rich subpopulation in this GC is also enhanced in CN and CH, showing a positive correlation between them. This trend is identical to the result we found in M22, suggesting that this might be a ubiquitous nature of GCs more strongly affected by SNe in their chemical evolution. Our results suggest that NGC 6273 was massive enough to retain SN ejecta, which would place this cluster in the growing group of GCs with Galactic building block characteristics, such as ω Centauri and Terzan 5.},
doi = {10.1088/2041-8205/813/2/L43},
journal = {Astrophysical Journal Letters},
number = 2,
volume = 813,
place = {United States},
year = {Tue Nov 10 00:00:00 EST 2015},
month = {Tue Nov 10 00:00:00 EST 2015}
}
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