J/AJ/130/2666 Ca4227 indices in early-type galaxies (Prochaska+, 2005)
A new definition for the Ca4227 feature: is calcium really underabundant in
early-type galaxies?
Prochaska L.C., Rose J.A., Schiavon R.P.
<Astron. J., 130, 2666-2676 (2005)>
=2005AJ....130.2666P 2005AJ....130.2666P
ADC_Keywords: Abundances ; Galaxies, spectra
Keywords: abundances - galaxies: evolution - galaxies: stellar content
Abstract:
We have investigated the abundance of calcium in early-type galaxies
by measuring the strength of the CaI λ4227 absorption line in
their integrated spectra. The database used is the large sample of
early-type galaxy integrated spectra in Caldwell and coworkers
(2003AJ....125.2891C 2003AJ....125.2891C). We have measured Ca abundances from the CaI
λ4227 feature both by using the Lick Ca4227 index and by
defining a new index, Ca4227r, that avoids the CN4216 molecular band
in the continuum on the blueward side of the line.
Description:
The observational data used in this paper consist of spectra of 175
early-type galaxies obtained with the 1.5m Tillinghast Telescope,
FAST, and a Loral 512x2688 pixel CCD at the F. L. Whipple Observatory.
The spectra were obtained at a dispersion of 0.75Å/pixel and a
resolution of 3.1Å FWHM.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 26 623 Ca4227r and Lick Ca4227 Index Measurements
(Jones Library Stars)
table3.dat 43 149 Ca4227r and Lick Ca4227 Index Measurements
(Galaxies and 47 Tuc)
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Name Source name
12- 18 F7.4 --- Ca4227r The Ca4227r index value
20- 26 F7.4 --- Lick4227 The Lick Ca4227 index value
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name Galaxy identification
11- 16 F6.4 --- Ca4227r The Ca4227r index value
18- 26 F9.7 --- e_Ca4227r The 1σ error in Ca4227r
28- 33 F6.4 --- Lick4227 The Lick Ca4227 index value
35- 43 F9.7 --- e_Lick4227 The 1σ error in Lick
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Marianne Brouty [CDS] 18-Jul-2006