LITHIUM ABUNDANCES OF THE SUPER-METAL-RICH OPEN CLUSTER NGC 6253

被引:33
作者
Cummings, Jeffrey D. [1 ]
Deliyannis, Constantine P. [2 ]
Anthony-Twarog, Barbara [3 ]
Twarog, Bruce [3 ]
Maderak, Ryan M. [2 ]
机构
[1] Univ Concepcion, Dept Astron, Concepcion, Chile
[2] Indiana Univ, Dept Astron, Bloomington, IN 47405 USA
[3] Univ Kansas, Dept Phys & Astron, Lawrence, KS 66045 USA
基金
美国国家科学基金会;
关键词
open clusters and associations: individual (NGC 6253; Hyades; M67; NGC; 3680; 752; IC; 4651); stars: abundances; techniques: spectroscopic; SOLAR-TYPE STARS; INTERNAL GRAVITY-WAVES; COSMIC-RAY NUCLEOSYNTHESIS; MAIN-SEQUENCE STARS; EVOLUTIONARY MODELS; STELLAR MODELS; HALO STARS; MICROSCOPIC DIFFUSION; CHEMICAL EVOLUTION; ANGULAR-MOMENTUM;
D O I
10.1088/0004-6256/144/5/137
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
High-resolution CTIO 4 m/HYDRA spectroscopy of the super-metal-rich open cluster NGC 6253 ([Fe/H] = +0.43 +/- 0.01) has been used to study the stellar lithium (Li) abundances near the cluster's turnoff. NGC 6253 greatly expands the range of [Fe/H] for clusters that have a Li abundance analysis. This is important for studying the complicated effects of, and potential correlations with, stellar Fe abundance on surface Li abundance. Comparisons to the younger and less-metal-rich Hyades and to the similarly aged but solar-metallicity M67 show that NGC 6253's Li abundances are qualitatively consistent with the prediction, from Standard Stellar Evolution Theory, that higher-metallicity stars have a greater Li depletion. Comparison with M67 provides evidence that the more-metal-rich NGC 6253 had a higher initial Li, which is consistent with expectations from models of Galactic Li production. NGC 6253 is also compared to the intermediate-aged NGC 3680, NGC 752, and IC 4651 open clusters. Comparison of the Li-gap positions in all six clusters shows that (1) the gap's position in T-eff is independent of metallicity, but (2) higher-metallicity clusters have their gaps in higher-mass stars. In addition, the Li gap's position is shown not to evolve with age, which provides an important constraint for the non-standard depletion mechanisms that may create the Li gap.
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页数:15
相关论文
共 77 条
[1]   ABUNDANCES OF THE ELEMENTS - METEORITIC AND SOLAR [J].
ANDERS, E ;
GREVESSE, N .
GEOCHIMICA ET COSMOCHIMICA ACTA, 1989, 53 (01) :197-214
[2]   WIYN OPEN CLUSTER STUDY. XXXIX. ABUNDANCES IN NGC 6253 FROM HYDRA SPECTROSCOPY OF THE Li 6708 Å REGION [J].
Anthony-Twarog, Barbara J. ;
Deliyannis, Constantine P. ;
Twarog, Bruce A. ;
Cummings, Jeffrey D. ;
Maderak, Ryan M. .
ASTRONOMICAL JOURNAL, 2010, 139 (05) :2034-2051
[3]   LITHIUM IN THE INTERMEDIATE-AGE OPEN CLUSTER, NGC 3680 [J].
Anthony-Twarog, Barbara J. ;
Deliyannis, Constantine P. ;
Twarog, Bruce A. ;
Croxall, Kevin V. ;
Cummings, Jeffrey D. .
ASTRONOMICAL JOURNAL, 2009, 138 (04) :1171-1191
[4]   Beryllium enhancement as evidence for accretion in a lithium-rich F dwarf [J].
Ashwell, Johanna F. ;
Jeffries, R. D. ;
Smalley, Barry ;
Deliyannis, C. P. ;
Steinhauer, Aaron ;
King, J. R. .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2005, 363 (01) :L81-L85
[5]   Lithium in lower main-sequence stars of the alpha Persei cluster (vol 333, pg 267, 1988) [J].
Balachandran, S ;
Lambert, DL ;
Stauffer, JR .
ASTROPHYSICAL JOURNAL, 1996, 470 (02) :1243-1244
[6]   THE LITHIUM DIP IN M67 - COMPARISON WITH THE HYADES, PRAESEPE, AND NGC-752 CLUSTERS [J].
BALACHANDRAN, S .
ASTROPHYSICAL JOURNAL, 1995, 446 (01) :203-227
[7]  
Balachandran S, 1991, ASP C SER, V13, P544
[8]   LITHIUM IN THE HYADES CLUSTER [J].
BOESGAARD, AM ;
TRIPICCO, MJ .
ASTROPHYSICAL JOURNAL, 1986, 302 (02) :L49-L53
[9]   LITHIUM IN THE HYADES, THE HYADES MOVING GROUP, AND PRAESEPE [J].
BOESGAARD, AM ;
BUDGE, KG .
ASTROPHYSICAL JOURNAL, 1988, 332 (01) :410-420
[10]   INFERRING THE SUNS INTERNAL ANGULAR VELOCITY FROM OBSERVED P-MODE FREQUENCY SPLITTINGS [J].
BROWN, TM ;
CHRISTENSENDALSGAARD, J ;
DZIEMBOWSKI, WA ;
GOODE, P ;
GOUGH, DO ;
MORROW, CA .
ASTROPHYSICAL JOURNAL, 1989, 343 (01) :526-546