Each file named t0xxx.dat corresponds to the evolutionary track of our helium 
white dwarf models of 0.xxx solar masses. 

In each file it is listed from left to right the following
quantities: (cgs units)
 
#1 :  log10(L/L_sun)    (surface luminosity)
#2 :  log10(T_eff)      (effective temperature)
#3 :  log10(T_c 6)      (central temperature in 10^6 K)     
#4 :  log10(rho_c)      (central density)
#5 :  age(yr)           (age in years counted from the end of mass loss episodes, see below ***)
#6 :  log10(R)          (stellar radius)
#7 :  log10(g)          (surface gravity)
#8 :  log10(L_nuc/Lsun) (hydrogen burning luminosity in solar units)
#9 :  X_H               (abundance by mass of hydrogen below the photosphere)
#10:  log10(M_H/M_*)    (mass of the hydrogen envelope in terms of the total stellar mass).                                                

*** The end of mass loss episode during the pre-wd evolution is taken to be at
Teff= 5000K for 0.406, 0.360, 0.327, 0.292 and 0.242 models  and  Teff= 10000K 
for 0.196 and 0.169 models.