An internet server for pre-main sequence tracks of low- and intermediate-mass stars

We present new grids of pre-main sequence (PMS) tracks for stars in the mas s range 0.1 to 7.0 M.. The computations were performed for four different m etallicities (Z=0.01, 0.02, 0.03 and 0.04). A fifth table has been computed for the solar composition (Z=0.02), including a moderate overshooting. We describe the update in the physics of the Grenoble stellar evolution code w hich concerns mostly changes in the equation of state (EOS) adopting the fo rmalism proposed by Pols et al. (1995) and in the treatment of the boundary condition. Comparisons of our models with other grids demonstrate the vali dity of this EOS in the domain of very low-mass stars. Finally, we present a new server dedicated to PMS stellar evolution which allows the determinat ion of stellar parameters from observational data, the calculation of isoch rones, the retrieval of evolutionary files and the possibility to generate graphic outputs.