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                                   SED 
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Synthetic Spectral Energy Distributions (SED) of Simple Stellar
Populations (SSP) are provided in separate files according to the
metallicity, the Initial Mass Function (IMF), and the HB morphology.

Composite Stellar Populations (CSP) following exponentially declining
star formation rates are provided for solar metallicity, Salpeter IMF,
and red Horizontal Branch. More CSP models will be made available soon
and this README file will be updated.

a) SSP

1) The naming is:

- sed.(IMF)(Metallicity).(HB morphology)

and the following acronyms are used:

for the IMF:

- ss = single Salpeter (1955) 
- kr = Kroupa (2001)

for the metallicity:

- z007  => [Z/H] = +0.67 (corresponding to Z=3.5 Zsun)
- z004  => [Z/H] = +0.35 (corresponding to Z=2.0 Zsun)
- z002  => [Z/H] = +0.00 (corresponding to Z=1.0 Zsun)
- z001  => [Z/H] = -0.33 (corresponding to Z=0.5 Zsun)
- z0001 => [Z/H] = -1.35 (corresponding to Z=1/50 Zsun)
- z10m4 => [Z/H] = -2.25 (corresponding to Z=1/200 Zsun)

for the Horizontal Branch morphology:

- bhb : blue morphology
- rhb : red  morphology

For example:

- sed.ssz10m4.bhb denotes the spectra of SSPs with a Salpeter IMF,
metallicity [Z/H] = -2.25 and blue Horizontal Branch morphology

2) The format of the spectra is:
  
 Age(Gyr)  [Z/H]  lambda(AA) F_{lambda}(erg/s^-1/AA) 

The fluxes are given in physical units and are normalized to 1 Msun.
If one wishes to express them in units of the solar bolometric
luminosity, they have to be divided per 3.826e33 (bolometric
luminosity of the Sun).

3) AGES: 

   - for the metallicities -1.35, -0.33, 0, 0.35, ages are given
   homogeneously from 10^3 yr to 15 Gyr according to a grid of 67 models
   (see enclosed file 'AgegridSSP', with ages in Gyr). 
   - for -2.25 and +0.67, models from 1 to 15 Gyr are provided.

4) For solar metallicity and Salpeter IMF, a set of synthetic
   SEDs in which half the mass loss in very massive stars is adopted 
   is also provided:

   File name: sed.ssz002.rhb.1mdot 

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b) CSP with exponentially declining star formation ('tau' models)

tau/Gyr:  0.10,0.25,0.40,0.50,0.75,1.00,1.25,1.50,1.75,2.00,2.25,2.50,
          2.75,3.00,3.50,4.00,5.00,10.00,20.00

1) The naming is: 

- csp_(SFH)_(metallicity)_(IMF).sed_agb

For example:

- csp_e10.0_z02_salp.sed denotes the spectra of CSPs with an e-folding
time of 10 Gyr, solar metallicity and Salpeter IMF

2) The format of the spectra is:
  
 Age(Gyr) lambda(AA) F_{lambda}(erg/cm^2/s^-1/AA) 

NB: 

The fluxes are given in physical units and are normalized to 1 Msun.
If one wishes to express them in units of the solar bolometric
luminosity, they have to be divided per 3.826e33 (bolometric
luminosity of the Sun).

3) AGES: ages are given from 1 Myr to 15 Gyr, according to a grid of 61 models
(see file 'Agegrid_CSP_Tau_Mar05', with ages in Gyr). 


* Note that in case of CSP ages mean time distances from the starting of star 
  formation *

4) MASSES: the true stellar masses and masses in remnants corresponding to the SEDs are given in
   the archive: Mass_Mar05_CSP_Tau_Salpeter.tar.gz

   Each individual file inside the archive refers to a specific tau 
   The naming is 

- csp_(SFH)_(metallicity)_(IMF).mass_agb	
	
  The format is:
  
 Age(Gyr)  M^*(total) M^*(living stars) M^*(White Dwarfs) M^*(Neutron Stars) M^*(Black Holes)  

Values are normalized to 1 Msun. The relationa initial mass/remnant mass are from 
Renzini & Ciotti (1993).

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References:

- Maraston, C. 2005, MNRAS, 362, 799
- Maraston, C. 1998, MNRAS, 300, 872