This program allows you to draw any type of H.-R. diagram with or without isochrones.
To proceed, select the metallicity and mass tracks that will appear in the graph. Then specify if you want to draw the ZAMS and/or isochrones for which you will speficy the age and finally indicate the units of your graph.

To convert the effective temperatures and luminosities resulting from our theoretical computations to colors and magnitudes, you have the choice to use the conversion table presented in Kenyon and Hartmann (1995, Astrophys. J. Suppl. Series 101, 117) or the one compiled by Siess et al. (1997, Astron. Astrophys. 324, 556). Note that in the latter case, only the B,V,R and I magnitudes are available. The colors are expressed in the Cousins system.

When the selected age for the isochrone is greater than the stellar age, we take the last value of (L,Teff) found in our files.
Reference to be mentioned:
Siess L., Dufour E., Forestini M. 2000, A&A, 358, 593 PDF


Z = 0.04 Z = 0.03 Z = 0.02 Z = 0.02+over Z = 0.01

Stellar models

Select the mass tracks that will be used to compute the isochrones

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.0
2.2 2.5 2.7 3.0 3.5 4.0 5.0 6.0 7.0


Start counting time from the birthline yes no

The birthline was computed with a mass accretion rate of $\dot M = 10^{-5} M_\odot yr^{-1}$
(see my PhD for details)

Plot ZAMS/early-MS $ $ ZAMS Early-MS none

the ZAMS is defined as the time, after deuterium burning, when the nuclear luminosity provides at least 99% of the total stellar luminosity, i.e. when Lnucl > 0.99 L
the early MS is defined as the time, when the star settles on the main sequence after the CN cycle has reached its equilibrium (this only affects stars with M>~1.2 Msun)

Plot isochrones yes no

Format : 1.5000d7 or 1500000

Label isochrones off on

When the age is out of range (e.g. a very large age for a massive star), the last point of the isochrone corresponds to the last value found in the stellar model file

Graphic output

Select Units

Set the limits yes no

Xmin Xmax
Ymin Ymax
(The numbers must be in log if the selected unit is Teff or L)
Label tracks off on

Distance Modulus

Conversion Table

Siess et al. (1997) Kenyon and Hartmann (1995)

Please note

  • if you want information in the K, J, H or L band you MUST use the Kenyon and Hartmann (1995) compilation.
  • the Siess et al. (1997) conversion table only provides the B, V, R and I magnitudes.