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J/ApJ/703/2177   Metal-poor MS turnoff stars summary (Schlaufman+, 2009)

Insight into the formation of the Milky Way through cold halo substructure. I. The ECHOS of Milky Way formation. Schlaufman K.C., Rockosi C.M., Prieto C.A., Beers T.C., Bizyaev D., Brewington H., Lee Y.S., Malanushenko V., Malanushenko E., Oravetz D., Pan K., Simmons A., Snedden S., Yanny B. <Astrophys. J., 703, 2177-2204 (2009)> =2009ApJ...703.2177S
ADC_Keywords: Milky Way ; Stars, metal-deficient Keywords: Galaxy: formation - Galaxy: halo - Galaxy: kinematics and dynamics Abstract: We identify 10 -- seven for the first time -- elements of cold halo substructure (ECHOS) in the volume within 17.5kpc of the Sun in the inner halo of the Milky Way. Our result is based on the observed spatial and radial velocity distribution of metal-poor main-sequence turnoff (MPMSTO) stars in 137 Sloan Extension for Galactic Understanding and Exploration lines of sight. We show that all of our detections are statistically significant and that we expect no false positives. These ECHOS represent the observable stellar debris of ancient merger events in the stellar accretion history of the Milky Way, and we use our detections and completeness estimates to infer a formal upper limit of 0.34+0.02-0.02 on the fraction of the MPMSTO population in the inner halo that belong to ECHOS. Description: The SEGUE survey obtained 240000 moderate-resolution (R∼1800) fiber-fed spectra of Milky Way stars in the magnitude interval 14.0<g<20.3. The spectroscopic targets were selected using SDSS photometry and additional SEGUE ugriz imaging data at low Galactic latitude and in the South Galactic Cap. In this analysis, we use the subset of SEGUE targets selected as metal-poor main-sequence turnoff (MPMSTO) stars. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table4.dat 69 137 Summary of completeness calculation
See also: II/294 : The SDSS Photometric Catalog, Release 7 (Adelman-McCarthy+, 2009) J/AJ/137/4377 : List of SEGUE plate pairs (Yanny+, 2009) J/AJ/136/2070 : SEGUE stellar parameter pipeline. III. (Allende Prieto+, 2008) J/AJ/136/2050 : SEGUE stellar parameter pipeline. II. (Lee+, 2008) Byte-by-byte Description of file: table4.dat
Bytes Format Units Label Explanations
1- 5 F5.1 deg RAdeg Right Ascension in decimal degrees (J2000) 7- 11 F5.1 deg DEdeg Declination in decimal degrees (J2000) 13- 17 F5.1 deg GLON Galactic longitude 19- 23 F5.1 deg GLAT Galactic latitude 25- 27 I3 --- Ns [10/173] Number of spectra obtained along that line of sight that lie in the inner halo as defined in Section 2 29- 32 I4 --- Np Number of photometrically classified MPMSTO stars in the volume scanned by SEGUE along that line of sight that lie in the inner halo as defined in Section 2 (1) 34- 38 F5.3 kpc3 Vol Volume 40 A1 --- l_Ob Limit flag on Ob 41- 45 F5.2 --- Ob [0/1] Fraction of total MPMSTO spectra sample that must belong to a single cold element of substructure for it to be classified as a bin detection 95% of the time (1) 47 A1 --- l_OI Limit flag on OI 48- 52 F5.2 --- OI [0/1] Fraction of total MPMSTO spectra sample that must belong to a single cold element of substructure for it to be classified as a class I detection 95% of the time (1) 54 A1 --- l_OII Limit flag on OII 55- 59 F5.2 --- OII [0/1] Fraction of total MPMSTO spectra sample that must belong to a single cold element of substructure for it to be classified as a class II detection 95% of the time (1) 61- 69 A9 --- Com Comment (Strm = stream)
Note (1): MPMSTO = metal-poor main-sequence turnoff stars. See Section 3.3 for the classes of peak detections.
History: From electronic version of the journal References: Schlaufman et al. Paper II. 2011ApJ...734...49S
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 03-Nov-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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