[Mesa-users] Adding mass and energy onto 0.2Mo star

[Bear Ealeal]

Dear Mesausers,

I am tryingto add mass, fast and in a short time for M dwarfs stars, from 0.2Mo.

I am addingthe mass when they are MS stars.

I tried afew examples:

low_z  (originally for 0.8 Msun, Z=1e-4)

make_zams_low_mass(originally for 0.085 Msun, Z = 0.014)

I alsotried the same issue on BD (although the physics is different),the same problemoccurs, I could get convergence at fast rates.

If I focus onthis example of: make_zams_low_mass

adding masswith "mass_change" and energy is very difficult, I made the numerics less tight:

!  numerics

      energy_eqn_option = 'dedt'

      use_gold2_tolerances = .true. 

      gold2_tol_residual_norm3 = 1d-7    

      solver_max_tries_before_reject=250

      varcontrol_target = 1d-3 

but I stillcant get convergence at all or in some cases I get convergence but not in reasonablerun time. I tried changing the atmosphere and  opacity, it did not help.

Do you haveany tips for me? on how to add mass and energy in a fast rate to these stars?

Thank youfor your help,

Ealeal

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