Synphot Data User's Guide

A.14 Bruzual-Charlot Atlas

---

This is a library of galaxy spectra computed by Bruzual and Charlot using their Isochrone Synthesis Spectral Evolutionary Code. The December 1995 version of the Bruzual-Charlot atlas consists of 21 instantaneous bursts characterized by different IMF slope functions, and mass limits. Each instantaneous burst contains 221 spectral energy distributions (SEDs) corresponding to 221 time steps from 0 to 20 Gyr.

The spectra represent bursts characterized by a Salpeter initial mass function (IMF) with different ranges in lower and upper mass limits, and at several ages (10E5, 25E5, 50E5, 76E5, 10E6, 25E6, 50E6, 10E7, 50E7, 10E8, 50E8, 10E9 years) after the burst. Spectra for instantaneous and composite bursts are available. Each spectrum has 1187 wavelength points covering the 100 Angstroms to 100 microns wavelength range, and the fluxes are given in units of solar luminosity per Angstrom. The nebular contribution to the spectral energy distribution, i.e., emission lines and nebular continuum, is not included in the spectra.

The spectra have names of the form bc95_a_XXXX through bc95_g_XXXX and are located in the crgrid$bc95/templates/ directory.