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README file for "Set III" data tables

In this dataset we give a summary of synthetic spectrophotometric indices for the Simple Stellar Population (SSP) models, including the main optical features in the Lick system (Faber et al. 1985, ApJS, 57, 711), two molecular indices of CO and H2O in the IR range about 2μ (Baldwin, Frogel & Persson 1973, ApJ, 184, 427), and two different measures of the 4000 Å Balmer break according to Brodie & Hanes (1986, ApJ, 300, 258). and Hamilton (1985, ApJ, 297, 371). For the sake of completeness, we also added to the database the integrated Johnson/Cousins/Gunn/Washington colors, as from Set I tables.

The integrated Lick and IR indices have been computed by means of different sets of stellar fitting functions, according to the following references:

Mg2: Buzzoni, A., Gariboldi, G., Mantegazza, L.: "The magnesium Mg2 index as an indicator of metallicity in elliptical galaxies", 1992, AJ, 103,1814
  
Hß, Fe5270, Fe5335: Buzzoni, A., Mantegazza, L., Gariboldi: "Metal enrichment in elliptical galaxies and globular clusters through the study of Iron and Hß spectral indices", 1994, AJ, 107, 513.
  
CO, H2O: Buzzoni, A.: "Evolutionary Population Synthesis in Stellar Systems. II. Early-Type Galaxies", 1995, 98, 69.

The Worthey et al. (1994, ApJS, 94, 687) fitting functions have also been applied to our SSP set, and the following synthetic indices have been derived: Ca4455,Fe4668,Mg2, Mgb, Hß, Fe5015, Fe5270, Fe5335, and Fe5406. For Mg2, Hß, Fe5270 and Fe5335 this eases a direct comparison of the Buzzoni's et al. and Worthey's et al. outputs allowing to assess the relevant differences between these two reference frameworks applied to the same set of SSPs.

Note that the Brodie & Hanes (1986, ApJ, 300, 258) 4000 Å break index (Δ) is expressed in magnitude scale, while the Hamilton (1985, ApJ, 297, 371) Δ4000 index is a flux ratio as originally defined in Bruzual (1983, ApJ, 273, 105). Each line in the Set III tables consists of the following 27 entries:

ColumnEntry
  
(1)Age in Gyr
(2)IMF power-law index "s" of the SSP (Salpeter=2.35)
(3)Stellar mass loss coefficient η, according to Reimers' formula (see the Set I Readme file) for details
(4)Metallicity parameter [Fe/H]. (Solar: [Fe/H]=0.00 by definition)
(5)Helium abundance Y (in mass)
(6)SSP integrated Mg2 index (in magnitudes), according to the Buzzoni et al. (1992) fitting functions
(7) Same as (6) but for the Hß index (in Å), according to the Buzzoni et al. (1994) fitting functions
(8) Same as (7) but for the Fe5270 index (in Å)
(9) Same as (7) but for the Fe5335 index (in Å)
(10) SSP integrated CO index (in magnitudes), according to the Buzzoni (1995) fitting functions
(11) Same as (10) but for the H2O index (in magnitudes)
(12)SSP integrated Ca4455 index (in Å), according to the Worthey et al. (1994) fitting functions
(13) Same as (12) but for the Fe4668 index (in Å)
(14) Same as (12) but for the Mg2 index (in magnitudes)
(15) Same as (12) but for the Hß index (in Å)
(16) Same as (12) but for the Mgb index (in Å)
(17) Same as (12) but for the Fe5015 index (in Å)
(18) Same as (12) but for the Fe5270 index (in Å)
(19) Same as (12) but for the Fe5335 index (in Å)
(20) Same as (12) but for the Fe5406 index (in Å)
(21) SSP 4000 Å Balmer break index (Δ, in magnitudes), as defined by Brodie & Hanes (1986)
(22) SSP 4000 Å Balmer break index (Δ4000, as a flux ratio), as defined by Hamilton (1985, ApJ, 297, 371) and Bruzual (1983, ApJ, 273, 105)
(23)Bolometric correction to Johnson V band from Set I. For the Sun we assume (Bol-V) = -0.07 and Mbol(sun)= +4.72.
(24-40)SSP integrated colors in the Johnson/Cousins system plus the conversion colors to the Gunn and Washington systems (from Set I; see the Readme file for calibration in the Rc and Ic Cousins system)
 
AB/Nov 2012

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