Stellar populations of Globular Clusters in the Elliptical galaxy NGC1407
| dc.creator | Cenarro, A. Javier | |
| dc.creator | Beasley, Michael A. | |
| dc.creator | Strader, Jay | |
| dc.creator | Brodie, Jean P. | |
| dc.creator | Forbes, Duncan A. | |
| dc.date | 2007-03-17 | |
| dc.date.accessioned | 2026-07-07T11:21:22Z | |
| dc.date.available | 2026-07-07T11:21:22Z | |
| dc.description | We present high-quality, Keck spectroscopic data for a sample of 20 globular clusters (GCs) in the massive E0 galaxy NGC1407. A subset of twenty line-strength indices of the Lick/IDS system have been measured for both the GC system and the central integrated star-light of the galaxy. Ages, metallicities and [alpha/Fe] ratios have been derived using several different approaches. The majority GCs in NGC1407 studied are old, follow a tight metallicity sequence reaching values slightly above solar, and exhibit mean [alpha/Fe] ratios of ~ 0.3 dex. In addition, three GCs are formally derived to be young (~ 4 Gyr), but we argue that they are actually old GCs hosting blue horizontal branches. We report, for the first time, evidence for the existence of two chemically-distinct subpopulations of metal-rich (MR) GCs. We find some MR GCs exhibit significantly larger [Mg/Fe] and [C/Fe] ratios. Different star formation time-scales are proposed to explain the correlation between Mg and C abundances. We also find striking CN overabundances over the entire GC metallicity range. Interestingly, the behavior of C and N in metal-poor (MP) GCs clearly deviates from the one in MR GCs. In particular, for MR GCs, N increases dramatically while C essentially saturates. This may be interpreted as a consequence of the increasing importance of the CNO cycle with increasing metallicity. | |
| dc.description | 53 pages, 11 figures, 5 tables. Accepted for publication in The Astronomical Journal | |
| dc.identifier | https://arxiv.org/abs/astro-ph/0703472 | |
| dc.identifier | http://arxiv.org/abs/astro-ph/0703472 | |
| dc.identifier | Astron.J.134:391-410,2007 | |
| dc.identifier | doi:10.1086/518504 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/194241 | |
| dc.subject | Astrophysics | |
| dc.title | Stellar populations of Globular Clusters in the Elliptical galaxy NGC1407 | |
| dc.type | text |