CDROM/APJS/V96/P009 Synthetic Properties of Starburst Galaxies (Leitherer+ 1995) ================================================================================ Synthetic Properties of Starburst Galaxies Claus Leitherer & Timothy M. Heckman <1995, ApJS, 96, 9> =1995ApJS...96....9L ================================================================================ Abstract: We present the results of an extensive grid of evolutionary synthesis models for populations of massive stars. The parameter space has been chosen to correspond to conditions typically found in objects like giant H II regions, H II galaxies, blue compact dwarf galaxies, nuclear starbursts, and infrared luminous starburst galaxies. The models are based on the most up-to-date input physics for the theory of stellar atmospheres, stellar winds, and stellar evolution. Observable properties of a population of stars are computed for the two limiting cases of an instantaneous burst and a constant star-formation rate over a time interval of 3x10^8 yr. We also investigate the effects of star-formation histories which are intermediate between those two extreme cases. Three choices of the initial mass functions are studies: a Salpeter and a Miller-Scalo type IMF with upper mass limits of 100 Msun, and a Salpeter IMF truncated at 30 Msun. Metallicities of 0.1 Zsun, 0.25 Zsun, Zsun, and 2 Zsun are considered. The model predictions include the numbers of hot stars, supernova rates, colors in the UBVRIJHKL passbands, slopes of the ultraviolet continuum observable by IUE, HST, and HUT, equivalent widths of hydrogen recombination lines, ionizing fluxes shortward of the H^0, He^0, and He^+ ionization edges, the Lyman discontinuity, and mass- and energy-deposition rates due to stellar winds and supernovae. We discuss the contamination of the stellar ultraviolet, optical, and near-infrared continuum by nebular emission. It is found that under typical starburst conditions the nebular continuum is not negligible. Depending on the wavelength, addition of the nebular continuum leads to significantly redder or bluer broadband colors than obtained from a pure stellar continuum. A population of massive stars is not only important in terms of its output of radiation but also via its deposition of mechanical energy. The output of radiative and mechanical luminosity is compared at various starburst epochs. In a supernova dominated instantaneous starburst, the mechanical luminosity can be as large as almost 10% of the total radiative luminosity. This occurs when most massive O stars have disappeared, and the synthetic spectrum in the optical and near-ultraviolet is dominated by B and A stars. During this epoch, the output of ionizing radiation below 912 A becomes very small, as indicated by a very large Lyman discontinuity and a very small ratio of ionizing over mechanical luminosity. We discuss the relevance of these results for the interpretation of starburst galaxies, active galactic nuclei, and the energetics of the interstellar medium. Keywords: galaxies: evolution -- galaxies: fundamental parameters -- galaxies: starburst -- galaxies: stellar content Description: There are 799 tables. Each table has 2 columns. The number of lines is different for each table. Column 1 is time in years, column 2 is the synthesized galaxy property as discussed in the printed paper. Each table contains the numbers used for the generation of the curves in the 71 figures of the paper. Since there is more than 1 curve in each figure, there are more than 71 tables. The files are stored in directories named for each figure: figure01, figure02, ... figure71. Figures 1 through 58 and 66 through 71 are identical in their structure. Each of these figures has 12 curves (3 in each of the 4 sub-figures). The curves are for 4 different metallicities and 3 different IMF parameters. Nomenclature: m10 - metallicity of Minus 1.0 (i.e. 0.1 solar) m06 Minus 0.6 (i.e. 0.25 solar) p00 Plus 0.0 (i.e. solar) p03 Plus 0.3 (i.e. 2 solar) 235 - IMF slope of 2.35 330 3.30 30 cut-off mass of 30 Example: figure10/m06_330.dat corresponds to Figure 10, metallicity 0.25 solar, and IMF slope of 3.3 Figures 59, 60, and 61 contain 5 curves each. Each curve is based on a different burst duration. Nomenclature: t00 - duration of 0 Myr t01 1 Myr t03 3 Myr t10 10 Myr t50 50 Myr Example: figure59/t10.dat is the 10 Myr model in Figure 59. Figures 62 through 65 have 4 curves each. They show the synthesized quantities with and without nebular emission for an instantaneous and continuous burst. Nomenclature: neb - nebular continuum included non nebular continuum not included bur instantaneous burst con continuous star formation Example: figure63/non_con.dat is the model without nebular continuum in a continuous burst in Figure 63. Byte-by-byte Description of files: figure*/*.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1-15 E15.7 yr Time Time in years 16-29 E14.7 --- Prop Synthesized galaxy property -------------------------------------------------------------------------------- ================================================================================ (End) Lee Brotzman [ADS] 07-May-95