Access to Astronomical Catalogues

← Click to display the menu
J/A+A/507/833       Interstellar CaII lines for 290 stars    (Megier+, 2009)

The interstellar CaII distance scale. Megier A., Strobel A., Galazutdinov G.A., Krelowski J. <Astron. Astrophys., 507, 833-840 (2009)> =2009A&A...507..833M
ADC_Keywords: Clusters, open ; Stars, early-type ; Equivalent widths ; Stars, distances Keywords: ISM: lines and bands - stars: distances - stars: early-type - open clusters and associations: general Abstract: We attempt to extend the relation between the strengths of the interstellar CaII lines and the distances to early-type stars to objects beyond 1 kiloparsec, with the line saturation taken into account. We measure the CaII K and CaII H equivalent widths, and compute Ca II column densities for 262 lines of sight towards early-type stars with available Hipparcos parallaxes (pi). The targets are located within a few hundred parsecs of the Galactic plane, and span all the range of Galactic longitudes. We fit the NCaII - parallax relation with a function of the form pi=1/(a.NCaII+b), using a maximum-likelihood approach to take account of errors in both variables. We use the resultant formula to estimate distances to stars in OB associations and clusters, and compare them to those found in the literature, usually estimated by spectrophotometric methods. Description: Most of the spectra were collected during research projects concerning diffuse interstellar bands. The first spectrometer is the MAESTRO fed by the 2-m telescope of the Observatory at Peak Terskol (TE) in the Northern Caucasus. The second spectrometer, covering the Southern hemisphere, is the FEROS spectrograph, fed by the 2.2m ESO telescope. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 113 290 Target stars
See also: I/239 : The Hipparcos and Tycho Catalogues (ESA 1997) J/AJ/117/354 : OB associations from Hipparcos (de Zeeuw+, 1999) Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 10 A10 --- Name Star name 12- 19 F8.4 deg GLON Galactic longitude (from SIMBAD) 21- 28 F8.4 deg GLAT Galactic latitude (from SIMBAD) 30- 34 F5.2 mas plx ?=- Trigonometric parallax (Hipparcos) 36- 39 F4.2 mas e_plx ?=- rms uncertainty on plx 41- 44 I4 0.1pm EWK Equivalent width of the CaII K line 46- 50 F5.2 0.1pm e_EWK rms uncertainty on EWK 51- 53 I3 0.1pm EWH Equivalent width of the CaII H line 55- 59 F5.2 0.1pm e_EWH rms uncertainty on EWK 61- 65 F5.2 10+12cm-2 NCaII CaII column density 67- 70 F4.2 10+12cm-2 e_NCaII rms uncertainty on NCaII 72- 79 A8 --- Assos Association membership 81- 88 A8 --- r_Assos Reference for association membership (1) 91- 94 I4 pc DH ?=- Association distance from Humphreys (1978ApJS...38..309H) 96- 99 I4 pc DGS ?=- Association distance from Garmany & Stencel (1992A&AS...94..211G) 101-103 I3 pc DZ ?=- Association distance from de Zeeuw et al. (1999, Cat. J/AJ/117/354) 105-108 I4 pc DCaII Distance estimated from formula (3) 110-113 I4 pc e_DCaII ? rms uncertainty pn DCaII
Note (1): Reference for association membership as follows: H = Humphreys (1978ApJS...38..309H) GS = Garmany and Stencel 1992A&AS...94..211G1992) Z = de Zeeuw et al. (1999, Cat. J/AJ/117/354) Note (3): The formula for estimating distance is: DCaII≃77+{2.78+(2.60/[EWK/EWH - 0.932])}*EWH
History: * From electronic version of the journal (units of galactic longitude, latitude, and parallaxes indicated as "mÅ" corrected)
(End) Patricia Vannier [CDS] 02-Mar-2010
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

© UDS/CNRS

Contact