Access to Astronomical Catalogues

← Click to display the menu
J/AJ/128/426        Subdwarfs in the SDSS                          (West+, 2004)

Spectroscopic properties of cool stars in the Sloan Digital Sky Survey: an analysis of magnetic activity and a search for subdwarfs. West A.A., Hawley S.L., Walkowicz L.M., Covey K.R., Silvestri N.M., Raymond S.N., Harris H.C., Munn J.A., Mcgehee P.M., Ivezic Z., Brinkmann J. <Astron. J., 128, 426-436 (2004)> =2004AJ....128..426W
ADC_Keywords: Stars, subdwarf ; Photometry, ugriz ; Equivalent widths Keywords: Galaxy: structure - solar neighborhood - stars: activity - stars: late-type - stars: low-mass, brown dwarfs - subdwarfs Abstract: We present a spectroscopic analysis of nearly 8000 late-type dwarfs in the Sloan Digital Sky Survey. Using the Hα emission line as an activity indicator, we investigate the fraction of active stars as a function of spectral type and find a peak near type M8, confirming previous results. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table2.dat 70 60 Subdwarf data
See also: : SDSS home page J/AJ/113/806 : M-Subdwarfs (Gizis 1997) Byte-by-byte Description of file: table2.dat
Bytes Format Units Label Explanations
1- 4 A4 --- --- [SDSS] 6- 24 A19 --- SDSS Object name 26- 30 F5.2 mag rmag ? SDSS r-band magnitude (1) 32- 36 F5.2 mag g-r ? SDSS (g-r) color (1) 38- 41 F4.2 mag r-i ? SDSS (r-i) color (1) 43- 46 F4.2 mag i-z ? SDSS (i-z) color (1) 48- 51 F4.2 --- TiO5 The TiO5 molecular band index 53- 56 F4.2 --- CaH1 The CaH1 molecular band index 58- 61 F4.2 --- CaH2 The CaH2 molecular band index 63- 67 F5.2 0.1nm EW ? Equivalent width of Hα in Angstroms (2) 69 I1 --- Sp The M spectral type subclass
Note (1): Photometry is omitted when uncertainties are larger than 0.2mag. Photometry is not available for some objects. Note (2): EW of subdwarfs that were either classified as active or inactive (see Section 3.2) are included.
History: From electronic version of the journal
(End) Greg Schwarz [AAS], Marianne Brouty [CDS] 06-Oct-2005
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

catalogue service