EZ Web

Contents

Overview

EZ Web generates an evolutionary sequence of stellar models, starting from a zero-age main sequence (ZAMS) model of specified mass and metallicity. It was written by Rich Townsend to provide an easy-to-use front end to Bill Paxton's Evolve ZAMS (EZ) stellar evolution code, which itself is a cut-down version of the Eggleton code.

To use EZ Web, simply edit the values in the form below, and hit submit. Your request will be added to a queue, and processed by EZ in a hopefully-timely manner (usually, it's pretty quick). Then, the resulting summary file and model files (if requested) will be packed into a Zip archive, and you will be sent an email containing instructions on downloading this archive.

If you encounter any problems, or have any suggestions or comments, please feel free to drop me an email (rhdt AT bartol DOT udel DOT edu).

Generate Sequence








Summary Files

The summary file created by EZ Web (summary.txt in the Zip archive) records the changes in the star's global, surface and central values as it evolves. Each line corresponds to a model at one specific timestep. In order, the columns contain the following data:

  1. Model number, starting from 00000
  2. Age (years)
  3. Mass (Msun)
  4. Log10 luminosity (Lsun)
  5. Log10 radius (Rsun)
  6. Log10 surface temperature (K)
  7. Log10 central temperature (K)
  8. Log10 central density (g cm-3)
  9. Log10 central pressure (dyn cm-2)
  10. Central degeneracy
  11. Central H mass fraction
  12. Central He mass fraction
  13. Central C mass fraction
  14. Central N mass fraction
  15. Central O mass fraction
  16. Dynamical timescale (years)
  17. Kelvin-Helmholtz timescale (years)
  18. Nuclear Timescale (years)
  19. Total power of H-burning via PP chain (Lsun)
  20. Total power of H-burning via CNO cycle (Lsun)
  21. Total power of He-burning (Lsun)
  22. Total power of Metal-burning (Lsun)
  23. Total power of Neutrino losses (Lsun)

Model Files

The model files created by EZ Web (model_NNNNN.txt in the Zip archive, where NNNNN is the model number) describe the complete structure of a model at one specific timestep. Each line corresponds to an individual mass shell of the star, ordered from the surface to the center. In order, the columns contain the following data:

  1. Mass coordinate (Msun)
  2. Radius coordinate (Rsun)
  3. Luminosity (Lsun)
  4. Pressure (dyn cm-2)
  5. Density (g cm-3)
  6. Temperatrure (K)
  7. Specific internal energy (ergs g-1)
  8. Specific entropy (ergs K-1 g-1)
  9. Specific heat at constant pressure (ergs K-1 g-1)
  10. First adiabatic exponent (Gamma1)
  11. Adiabatic temperature gradient
  12. Mean molecular weight
  13. Electron number density (cm-3)
  14. Electron partial pressure (dyn cm-2)
  15. Radiation partial pressure (dyn cm-2)
  16. Radiative temperature gradient
  17. Physical temperature gradient
  18. Convective velocity (cm s-1)
  19. Opacity (cm2 g-1)
  20. Total nuclear power (ergs g-1 s-1)
  21. PP-chain power (ergs g-1 s-1)
  22. CNO-cycle power (ergs g-1 s-1)
  23. Triple-alpha power (ergs g-1 s-1)
  24. Neutrino loss power (ergs g-1 s-1)
  25. H mass fraction
  26. H2 mass fraction
  27. H+ mass fraction
  28. He mass fraction
  29. He+ mass fraction
  30. He++ mass fraction
  31. C mass fraction
  32. N mass fraction
  33. O mass fraction
  34. Degeneracy parameter