J/AJ/116/1922 CaII H and K filter photometry III. (Anthony-Twarog+, 1998)
Ca II H and K photometry on the uvby system.
III. The metallicity calibration for the red giants.
Anthony-Twarog B.J., Twarog B.A.
<Astron. J. 116, 1922 (1998)>
=1998AJ....116.1922A 1998AJ....116.1922A (SIMBAD/NED BibCode)
ADC_Keywords: Photometry, uvby ; Stars, population II
Keywords: stars: abundances - stars: Population II - techniques: photometric
Abstract:
New photometry on the uvby Ca system is presented for over 300 stars.
When combined with previous data, the sample is used to calibrate the
metallicity dependence of the hk index for cooler, evolved stars. The
metallicity scale is based upon the standardized merger of
spectroscopic abundances from 38 studies since 1983, providing an
overlap of 122 evolved stars with the photometric catalog. The hk
index produces reliable abundances for stars in the [Fe/H] range from
-0.8 to -3.4, losing sensitivity among cooler stars due to saturation
effects at higher [Fe/H], as expected.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 93 302 New CTIO 1 meter photometry
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See also:
J/AJ/109/2828 : CaII H and K filter photometry II. (Twarog+ 1995)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- Star HD or BD name
14- 19 F6.3 mag Vmag V magnitude
21- 25 F5.3 mag b-y b-y colour index
27- 32 F6.3 mag m1 ? m1 colour index
34- 38 F5.3 mag c1 ? c1 colour index
40- 44 F5.3 mag hk hk [(Ca-b) - (b-y)] colour index
46- 50 F5.3 mag e_Vmag rms uncertainty on Vmag
52- 56 F5.3 mag e_b-y rms uncertainty on b-y
58- 62 F5.3 mag e_m1 ? rms uncertainty on m1
64- 68 F5.3 mag e_c1 ? rms uncertainty on c1
70- 74 F5.3 mag e_hk rms uncertainty on hk
76- 77 I2 --- o_Vmag Number of nights on which V, b-y and hk
were observed
79- 80 I2 --- o_m1 Number of nights on which m1 and c1 were
observed
82- 93 A12 --- Names Other names
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History: From AJ electronic version
References:
Anthony-twarog et al., Paper I. 1991AJ....101.1902A 1991AJ....101.1902A
Twarog & Anthony-twarog, Paper II. 1995AJ....109.2828T 1995AJ....109.2828T, Cat. J/AJ/109/2828
(End) James Marcout, Patricia Bauer [CDS] 09-Mar-1999