J/AJ/127/1513 Lick indices on M67 members (Schiavon+, 2004)
The integrated spectrum of M67 and the spectroscopic age of M32.
Schiavon R.P., Caldwell N., Rose J.A.
<Astron. J., 127, 1513-1530 (2004)>
=2004AJ....127.1513S 2004AJ....127.1513S
ADC_Keywords: Clusters, open ; Photometry
Keywords: galaxies: clusters: general - galaxies: individual (M32) -
galaxies: stellar content -
open clusters and associations: individual (M67) - stars: evolution
Abstract:
We construct an integrated spectrum of the intermediate-age,
solar-metallicity Galactic cluster M67, from individual spectroscopic
observations of bona fide cluster members. The spectrum so obtained is
used as a template to test our stellar population synthesis models, in
an age and metallicity regime where such models remain largely
untested. As a result, we demonstrate that our models predict a
spectroscopic age of 3.5±0.5Gyr for M67, which is the same age we
obtain from fitting isochrones to the color-magnitude diagram of the
cluster. Full consistency is reached when using either Hβ,
Hγ, or Hδ as the age indicator. We also check if the
models, when applied to the cluster integrated spectrum, predict
elemental abundances in agreement with the known detailed abundance
pattern of the cluster. The models also pass the latter test, by
predicting the abundances of iron, magnesium, carbon, and nitrogen in
agreement with detailed abundance analyses of cluster stars to within
0.1dex. Encouraged by the high degree of consistency of our models, we
apply them to the study of the integrated spectrum of the central 3"
of the compact elliptical galaxy M32.
Objects:
-----------------------------------------
RA (2000) DE Designation(s)
-----------------------------------------
08 51.3 +11 50 M 67 = NGC 2682
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 56 26 Stars not found to be members on M67
table2.dat 49 69 Stars found to be members of M67 and used in the
construction of the cluster integrated spectrum
table3.dat 31 17 Field stars included in the construction of the
integrated spectrum of M67
table6.dat 95 95 Lick indices measured in the spectra of field
and M67 Stars
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See also:
J/AJ/106/181 : CCD photometry of open cluster M67 (Montgomery+ 1993)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- Name Stellar identification (1)
12- 13 I2 h RAh Hour of right ascension (J2000)
15- 16 I2 min RAm Minute of right ascension (J2000)
18- 22 F5.2 s RAs Second of right ascension (J2000)
24 A1 --- DE- Sign of declination (J2000)
25- 26 I2 deg DEd Degree of declination (J2000)
28- 29 I2 arcmin DEm Arcminute of declination (J2000)
31- 34 F4.1 arcsec DEs Arcsecond of declination (J2000)
36- 41 F6.3 mag Vmag The V-band magnitude
43- 48 F6.3 mag B-V The (B-V) color index
50- 56 A7 --- Crit Criteria for non-membership (2)
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Note (1): Following the nomenclature of Montgomery, Marschall, & Janes,
1993, Cat. J/AJ/106/181, MMJ NNN: CL* NGC 2682 MMJ NNNN in Simbad
Note (2): Reasons for determination of non-membership are:
1: radial velocity
2: proper motion
3: position in CMD
4: metallicity
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Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- Name Stellar identification (1)
12- 13 I2 h RAh Hour of right ascension (B1950)
15- 16 I2 min RAm Minute of right ascension (B1950)
18- 22 F5.2 s RAs Second of right ascension (B1950)
24 A1 --- DE- Sign of declination (B1950)
25- 26 I2 deg DEd Degree of declination (B1950)
28- 29 I2 arcmin DEm Arcminute of declination (B1950)
31- 34 F4.1 arcsec DEs Arcsecond of declination (B1950)
36- 41 F6.3 mag Vmag The V-band magnitude
43- 48 F6.3 mag B-V The (B-V) color index
50- 56 A7 --- Crit Criteria for non-membership (2)
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Note (1): Following the nomenclature of Montgomery, Marschall, & Janes,
1993, Cat. J/AJ/106/181, MMJ NNN: CL* NGC 2682 MMJ NNNN in Simbad
Note (2): Reasons for determination of non-membership are:
1: radial velocity
2: proper motion
3: position in CMD
4: metallicity
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Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- Name Star name
12- 17 F6.3 mag Vmag V magnitude
19- 22 F4.2 mag B-V B-V color index
24- 31 A8 --- SpType MK Spectral type
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Byte-by-byte Description of file: table6.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- Name Stellar identification (1)
12- 18 F7.4 0.1nm HdF Lick/IDS HδF index (e_HdF=0.03) (2)
20- 26 F7.4 mag CN1 Lick/IDS CN1 index (e_CN1=0.007) (2)
28- 34 F7.4 mag CN2 Lick/IDS CN2 index (e_CN2=0.0004) (2)
36- 42 F7.4 0.1nm G4300 Lick/IDS G4300 index (e_G4300=0.005) (2)
44- 50 F7.4 0.1nm HgF Lick/IDS HγF index (e_HgF=0.02) (2)
52- 58 F7.4 0.1nm Fe4383 Lick/IDS Fe4383 index (e_Fe4383=0.04) (2)
60- 65 F6.4 0.1nm Hb Lick/IDS Hβ index (e_Hb=0.04) (2)
67- 73 F7.4 0.1nm Mgb Lick/IDS Mg b index (e_Mgb=0.08) (2)
75- 80 F6.4 mag Mg2 Lick/IDS Mg2 index (e_Mg2=0.005)(2)
82- 87 F6.4 0.1nm Fe5270 Lick/IDS Fe5270 index (e_Fe5270=0.02) (2)
89- 94 F6.4 0.1nm Fe5335 Lick/IDS Fe5335 index (e_Fe5335=0.04) (2)
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Note (1): The identification numbers of M67 (MMJ NNNN) stars are from
Montgomery et al., 1993, Cat. J/AJ/106/181, Cl* NGC 2682 MMJ NNNN in
Simbad, else, HD designation.
Note (2): Mean errors estimated as described in section 2.2.1.
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History:
* 06-Apr-2004: From electronic version of the journal
* 06-Jan-2005: Equinox of position of table1 corrected
(J2000 instead of B1950)
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 06-Apr-2004