J/AJ/127/1588 47 Tuc main-sequence star abundances (Briley+, 2004)
On the carbon and nitrogen abundances of 47 Tucanae's main-sequence stars.
Briley M.M., Harbeck D., Smith G.H., Grebel E.K.
<Astron. J., 127, 1588-1593 (2004)>
=2004AJ....127.1588B 2004AJ....127.1588B
ADC_Keywords: Clusters, globular ; Stars, dwarfs ; Abundances
Keywords: globular clusters: general -
globular clusters: individual (47 Tucanae) - stars: evolution -
stars: abundances
Abstract:
We report the results of an analysis of CN and CH band strengths among
a large sample of 47 Tucanae main-sequence and turnoff stars presented
earlier by Harbeck et al. (2003, Cat. J/AJ/125/197).
Description:
The sample selection, observations, and reduction of the 47 Tuc MS and
MSTO spectra used in this analysis are described in Harbeck et al.
(2003, Cat. J/AJ/125/197). To summarize, 115 program stars were
selected from MPG/ESO 2.2m images of 47 Tuc to span a range in
luminosity from the MSTO to 2.5mag fainter. Photometry of the stars
was also extracted from these images. The spectra were obtained at the
ESO Very Large Telescope.
Objects:
----------------------------------------------------------
RA (2000) DE Designation(s)
----------------------------------------------------------
00 24 05.2 -72 04 58 47 Tuc = NGC 104
----------------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 74 109 Observed Indices, Model Parameters, and
Resulting Abundances
--------------------------------------------------------------------------------
See also:
J/AJ/125/197 : CN abundances of the 47 Tuc main sequence (Harbeck+, 2003)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 --- HSG Identification number, Cl* NGC 104 HSG NNNN
6- 11 F6.3 mag Vmag Johnson V band magnitude (1)
13- 17 F5.3 mag B-V Johnson (B-V) color index (1)
19- 24 F6.3 --- S3839 CN (S(3839)) index
26- 30 F5.3 --- I(CH) CH (I(CH)) index
32- 37 F6.3 --- MgH ? The MgH index (2)
39 A1 --- Memb [YN?] Cluster membership (3)
41- 44 I4 K Teff ? Effective temperature
46- 49 F4.2 [cm/s2] log(g) ? Log of the surface gravity
51- 55 F5.2 [---] [C/Fe] ? Log of the carbon to iron abundance
57- 60 F4.2 [---] [N/Fe] ? Log of the nitrogen to iron abundance
62- 67 F6.3 --- MS3839 ? Model value for S3839
69- 73 F5.3 --- MI(CH) ? Model value for I(CH)
--------------------------------------------------------------------------------
Note (1): Note that the V, B-V values of Harbeck et al. (2003, J/AJ/125/197)
include an extinction correction of 0.128 and 0.04 (respectively).
The values listed here are uncorrected.
Note (2): Nine spectra did not extend redward enough for the MgH index to
be measured. They are assumed to be members based on the criteria of
Harbeck (2003, J/AJ/125/197) and included in the subsequent analysis.
No modeling was done for the presumed non-members.
Note (3): Membership flags:
Y = cluster member;
N = not a cluster member;
? = no MgH index available (see Note 2).
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 17-May-2004