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J/AJ/106/1839              Metal-rich halo A stars (Rodgers+ 1993)

Early-type stars in orthogonal halo fields. II. Identification of metal-rich A stars in the halo Rodgers A.W., Roberts W.H. <Astron. J. 106, 1839 (1993)> =1993AJ....106.1839R
ADC_Keywords: Stars, early-type ; Radial velocities ; Equivalent widths Abstract: The results of spectrophotometry of the Ca II K and Balmer lines and radial velocity measurements for stars earlier than type F0, with 10<V<15.5 in fields at (l;b)=(90deg, 270deg; -45deg) are reported. Slit spectroscopy of 320 stars shows that in this magnitude range there are ∼80 stars with [Fe/H]>-0.5. The metal-rich population has a vertical scale height of ∼600pc and a space density at the Sun equal to 1/225 of the young thin disk A star population. The metal-rich A stars have Vrot=210±60km/s with decreasing angular momentum as a function of distance from the Galactic plane. The line-of-sight velocity dispersion is 40±3km/s indicating an anomalous relation between structure and kinematics. There is strong evidence that these stars are identical in properties to the metal-rich extended populations found by Perry [1969AJ.....74..139P] at the NGP and Rodgers [1971ApJ...165..581R] at the SGP. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 43 332 Spectrophotometry and radial velocities of stars classified as of type earlier than F0 in the fields (l;b)=(90 deg, 270 deg; -45 deg) from the catalog of Paper I
See also: J/AJ/106/591 : OP Survey of Halo early-type stars (Rodgers+ 1993) Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 9 A9 --- Name Object identifier 11- 14 F4.1 0.1nm EWK Equivalent width of Ca II K 16- 20 F5.1 0.1nm EWHd Equivalent width of Ca II Hdelta 22- 26 I5 km/s RV *Radial velocity rel. to Local Std. of Rest 28- 35 F8.3 deg GLON Galactic longitude 37- 43 F7.3 deg GLAT Galactic latitude
Note on RV: The following corrections were adopted: for l=90 deg; b=-45 deg, Vlsr=Vhelio+6km/s for l=270 deg; b=-45 deg, Vlsr=Vhelio-16km/s
Referneces: Rodgers A.W. & Roberts W.H., Paper III. =1993AJ....106.2294R Origin: AAS CD-ROM series, Volume 6, 1996 Lee Brotzman [ADS] 19-Feb-1996
(End) [CDS] 05-Sep-1996
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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