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J/A+A/534/A136    Halo red giants from the SEGUE survey      (Martell+, 2011)

Building the Galactic halo from globular clusters: evidence from chemically unusual red giants. Martell S.L., Smolinski J.P., Beers T.C., Grebel E.K. <Astron. Astrophys. 534, A136 (2011)> =2011A&A...534A.136M
ADC_Keywords: Clusters, globular ; Stars, halo ; Stars, giant ; Abundances ; Photometry, SDSS Keywords: stars: abundances - Galaxy: halo - Galaxy: formation Abstract: We present a spectroscopic search for halo field stars that originally formed in globular clusters. Using moderate-resolution SDSS-III/SEGUE-2 spectra of 561 red giants with typical halo metallicities (-1.8≤[Fe/H]≤-1.0), we identify 16 stars, 3% of the sample, with CN and CH bandstrength behavior indicating depleted carbon and enhanced nitrogen abundances relative to the rest of the data set. Since globular clusters are the only environment known in which stars form with this pattern of atypical light-element abundances, we claim that these stars are second-generation globular cluster stars that have been lost to the halo field via normal cluster mass-loss processes. Description: Table 1 lists SDSS identifiers, astrometry and photometry, stellar parameters and survey name for 2519 stars observed as part of the SDSS-II/SEGUE-1 and SDSS-III/SEGUE-2 surveys. The stars in this table were selected as red giants with halo-like metallicities (-1.8<[Fe/H]←1.0) and reasonably clean spectra (mean S/N per pixel between 4000 and 4100A greater than 15). Table 3 lists SDSS identifiers, CN and CH bandstrength indices, CN bandstrength class, absolute r magnitudes, heliocentric and Galactocentric distances, and survey name, for the same stars as in Table 1. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 100 2519 Photometry, stellar parameters, and survey name for each star in the final data set from this study and the final data set from Martell & Grebel (2010A&A...519A..14M) table3.dat 58 2519 Measured values for the same stars as in Table 1
See also: http://www.sdss.org : SDSS Home Page Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 4 A4 --- --- [SDSS] 6- 24 A19 --- SDSS Unique SDSS identifier, JHHMMSS.ss+DDMMSS.s 26- 29 I4 --- Plate SDSS plug-plate number 31- 35 I5 --- MJD Modified Julian date of observation 37- 39 I3 --- Fiber Fiber number 41- 42 I2 h RAh Right ascension (J2000) 44- 45 I2 min RAm Right ascension (J2000) 47- 51 F5.2 s RAs Right ascension (J2000) 53 A1 --- DE- Declination sign (J2000) 54- 55 I2 deg DEd Declination (J2000) 57- 58 I2 arcmin DEm Declination (J2000) 60- 64 F5.2 arcsec DEs Declination (J2000) 66- 70 F5.2 mag g0 Dereddened apparent g magnitude 72- 76 F5.3 mag (g-r)0 Dereddened apparent (g-r) color index 78- 82 F5.2 [Sun] [Fe/H] Metallicity 84- 87 I4 K Teff Effective temperature 89- 92 F4.2 [cm/s2] logg Surface gravity 94- 99 A6 --- --- [SEGUE-] 100 A1 --- S [12] Survey name : SEGUE-1 or SEGUE-2
Byte-by-byte Description of file: table3.dat
Bytes Format Units Label Explanations
1- 4 I4 --- Plate SDSS plug-plate number 6- 10 I5 --- MJD Modified Julian date of observation 12- 14 I3 --- Fiber Fiber number 16- 21 F6.3 mag S(CN) CN bandstrength index at 3883Å (1) 23- 27 F5.3 mag S(CH) CH bandstrength index at 4320Å (2) 29- 34 A6 --- CN CN class, as "Normal" or "Strong" 36- 40 F5.2 mag rMAG Absolute r magnitude 42- 45 F4.1 kpc Dist Heliocentric distance 47- 50 F4.1 kpc rGC Galactocentric distance 52- 57 A6 --- --- [SEGUE-] 58 A1 --- S [12] Survey name : SEGUE-1 or SEGUE-2
Note (1): CN bandstrength index, S(3839) (Norris et al. 1981ApJ...244..205N) Note (2): CH bandstrength index, S(CH) (Martell et al. 2008PASP..120....7M)
Acknowledgements: Sarah Martell, martell(at)ari.uni-heidelberg.de History: * 19-Sep-2011: Original version * 11-Mar-2013: Complete SDSS names added in table1 (supplied by Sarah Martell)
(End) Martell [ARI/ZAH, Heidelberg], Patricia Vannier [CDS] 19-Sep-2011
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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