[mesa-users] Test suite CCSN problem

[Manos Chatzopoulos]

Hi all,

  The original, test_suite ccsn problem in the latest public release of 
MESA runs fine but I have a couple of question
with regards to optimizing it for another application:

1) Is there a special reason this very particular and accurate value for 
SN energy injection in the inlist_edep
was chosen?:

      inject_until_reach_delta_total_energy = 1.51935238181291335e51
       inject_extra_ergs_sec = 1.51935238181291335e51 ! erg/s

Is that a value determined based on the gravitational bounding energy of 
the core, an integrated
thermal energy required to unbind the star or something else? Because if 
I choose this value
even by a bit (1.6e51 erg) the ccsn run does not work (it fails during 
edep and before explosion).

2) Even without changing the injected energy in inlist_edep I wished to 
follow the SN shock for
longer; obviously not until shock break-out (that cannot be done 
properly at this time) but at least
up to mass of ~10-11 Msun (out of ~12 Msun that is left - therefore 
still within the optically thick
region of the star, deep beneath the surface and in the hydrogen envelope).
I changed   x_ctrl(1) to 10. thinking this will do the trick but the run 
failed again with convergence problems:

                       dt_div_dt_Courant        3.8739805487249512
                             total_energy    1.2004485474821978D+51
          log_rel_cumulative_energy_error       -2.8599403101283558
              rel_cumulative_energy_error       -0.0013805739990469
         rel_error_in_energy_conservation   -7.4721951660307834D-10
                           avg_E_residual   -2.8042773685002612D-10
                           max_E_residual   -1.4603660217645308D-06

hydro_newton_step returned ierr
        retry cnt, step, log10(dt/yr), retry_factor     1  1672 
-6.324885        0.500000
                                             num_retries         401
                                      max_number_retries         400

  stopping because of convergence problems -- too many retries


terminated evolution: nonzero_ierr

termination code: max_number_retries

Anyone has a trick that will allow me to follow the shock for longer and 
further out in the star?

Thanks,

Manos

-- 
Dr. Emmanouil Chatzopoulos
Enrico Fermi Postdoctoral Fellow
Department of Astronomy & Astrophysics
FLASH Center for Computational Science
University of Chicago
https://www.linkedin.com/pub/manos-chatzopoulos/a1/688/a03
https://astro.uchicago.edu/people/manos-chatzopoulos.php