# Changelog¶

## Changes in r15140¶

### Backwards-incompatible changes¶

#### Addition of eos and kap namelists¶

The options associated with the eos and kap modules have been moved into their own namelists. (That is, there now exist &eos and &kap at the same level as &star_job and &controls.) User inlists will need to be updated. See Module-level changes for more specific information.

If you previously accessed the values of eos/kap related options from star_job or controls via run_star_extras, you will need to adjust your code to access the option values using the pointers to the EoS_General_Info and Kap_General_Info structures. These are exposed in star as s% eos_rq and s% kap_rq, respectively. So for example, the inlist value of Zbase is now accessible via s% kap_rq% Zbase (instead of s% Zbase).

#### Some file suffixes changed to .f90¶

Many source file names have been changed to have an .f90 suffix. For users, the most important changes are to the star and binary work directories.

In an existing star work directory (i.e., a copy of star/work or star test suite case), rename the files

• src/run.fsrc/run.f90
• src/run_star_extras.fsrc/run_star_extras.f90

In an existing binary work directory (i.e., a copy of binary/work or binary test suite case), rename the files

• src/binary_run.fsrc/binary_run.f90
• src/run_star_extras.fsrc/run_star_extras.f90
• src/run_binary_extras.fsrc/run_binary_extras.f90

Changes to local makefiles that are not part of MESA might also need to be updated to reflect these changes.

#### Removal of backups¶

MESA no longer has the concept of a “backup”. (In a backup, after the failure of a retry, MESA would return to the previous model and evolve it with a smaller timestep.)

Models that previously relied on the use of backups in order to complete should instead use appropriate timestep controls such that retries alone are sufficient to enable the model to run.

All backup-related options and output quantities have been removed. Users migrating inlists or history_column.list files from previous MESA versions will need to remove these options, all of which contain the string “backup”.

#### Changes to solver reporting¶

MESA can report information about the progress of the iterative Newton–Raphson solution process that forms a key part of taking a timestep. The names of numerous options related to the solver have changed. These changes follow two main patterns.

First, the word “newton” was replaced with the word “solver”. For example, the history column that records the number of iterations changed from num_newton_iterations to num_solver_iterations. The controls option that defines a number iterations above which to reduce the timestep changed from newton_iterations_limit to solver_iters_timestep_limit and the terminal output correspondingly shows the message solver iters instead of newton iters. (The control newton_iterations_hard_limit was removed and not renamed.)

Second, the word “hydro” was removed or replaced with the word “solver” in the controls related to monitoring the solver internals. For example, the control report_hydro_solver_progress is now report_solver_progress and report_hydro_dt_info is now report_solver_dt_info. The use of these and other related controls is described in the developer documentation.

#### Changes to eps_grav and eps_mdot¶

A new method for handling the energetics associated with mass changes in MESA models was presented in MESA V, Section 3.2. The approach discussed therein, incorporated in a term named eps_mdot, has now become standard. As such, the option use_eps_mdot has been removed (because it is now effectively always true).

This eps_mdot approach supersedes the approach described in MESA III, Section 7, and so that implementation has been removed. This resulted in the removal of the &controls options

• eps_grav_time_deriv_separation
• zero_eps_grav_in_just_added_material
• min_dxm_Eulerian_div_dxm_removed
• min_dxm_Eulerian_div_dxm_added
• min_cells_for_Eulerian_to_Lagrangian_transition
• fix_eps_grav_transition_to_grid

the history columns

• k_below_Eulerian_eps_grav
• q_below_Eulerian_eps_grav
• logxq_below_Eulerian_eps_grav
• k_Lagrangian_eps_grav
• q_Lagrangian_eps_grav
• logxq_Lagrangian_eps_grav

and the profile columns

• eps_grav_h_effective
• eps_mdot_sub_eps_grav_h_effective
• eps_mdot_rel_diff_eps_grav_h_effective
• eps_grav_h
• eps_mdot_sub_eps_grav_h
• eps_mdot_rel_diff_eps_grav_h

#### Removal of lnPgas_flag¶

The option to use gas pressure instead of density as a structure variable has been removed. Users migrating inlists from previous MESA versions will need to remove these options, all of which contain the string “lnPgas_flag”.

#### Removal of logQ limits¶

As a consequence of the changes to eos, star no longer enforces limits on the quantity logQ (logQ = logRho - 2*logT + 12 in cgs). Therefore the controls options

• logQ_limit
• logQ_min_limit

and the pgstar option

• show_TRho_Profile_logQ_limit

have been removed.

The removal of these controls does not indicate that the EOS is reliable at all values of logQ. Users should consult the description of the component EOSes and the regions in which they are applied to understand if MESA provides a suitable EOS for the conditions of interest.

#### Removal of GR factors¶

The control use_gr_factors and corresponding code has been removed. (This provided only a simple correction to the momentum equation and not a full GR treatment of the stellar structure equations.) Users wishing to include GR corrections to MESA’s Newtonian equations can achieve the same effect by using the other_cgrav or other_momentum hooks. For an example, see the neutron star test cases (ns_h, ns_he, and ns_c).

#### Change in STELLA file output¶

The options to create output files suitable for input to STELLA have been removed from MESA/star and the star_job namelist. These capabilities are now included as part of the ccsn_IIp test case (see inlist_stella and run_star_extras.f90). Users desiring STELLA-format output should re-use the code from that example.

This affects the options

• save_stella_data_for_model_number
• save_stella_data_when_terminate
• save_stella_data_filename
• stella_num_points
• stella_nz_extra
• stella_min_surf_logRho
• stella_min_velocity
• stella_skip_inner_dm
• stella_skip_inner_v_limit
• stella_mdot_years_for_wind
• stella_mdot_for_wind
• stella_v_wind
• stella_show_headers

#### Removal of mesh adjustment parameters around convective boundaries¶

Controls matching the following patterns, which adjust the mesh resolution around convective boundaries, have been removed:

• xtra_coef_czb_full_{on,off}
• xtra_coef_{a,b}_{l,u}_{n,h,he,z}b_czb
• xtra_dist_{a,b}_{l,u}_{n,h,he,z}b_czb
• xtra_coef_scz_above_{n,h,he,z}b_cz

Convective boundaries can be resolved using a custom mesh-spacing function or mesh_delta coefficient. The simplex_solar_calibration test case has an example custom mesh-spacing function.

#### Change to mixing_type codes¶

The mixing_type codes (defined in const/public/const_def.f90) have changed. User code and/or analysis routines (e.g., scripts interpreting the mixing_type profile column) may need to be revised. We recommend that users use the mixing_type variables rather than the corresponding integers in their own code. e.g. rather than writing

if (mixing_type == 1) then


use

if (mixing_type == convective_mixing) then


assuming use const_def appears somewhere, as in the default run_star_extras.f90.

#### Limitations on use of varcontrol_target¶

A new variable min_allowed_varcontrol_target (default 1d-4) has been introduced to discourage the use of small values of varcontrol_target. MESA will exit with an error if the value is below this threshold.

The value of varcontrol is an unweighted average over all cells of the relative changes in the structure variables. For situations that need tighter timestep limits, there are many specific timestep controls that should be used instead of reducing the general target. The use of controls that specifically apply to the problem being studied will typically provide more effective and efficient timestep limiters. In addition, small values of varcontrol_target can lead to poor performance when it forces the size of the step-to-step corrections to become too small.

The option varcontrol_target is NOT the recommended way to push time resolution to convergence levels. To perform temporal convergence studies, use the new control time_delta_coeff, which acts as a multiplier for timestep limits (analogous to mesh_delta_coeff for spatial resolution).

One strategy for choosing effective timestep limits is to first set varcontrol_target = 1d-3. Then add some additional specific timestep limits relevant to the problem. Do a run, watching the reason for the timestep limits and the number of retries. Summary information about the conditions that limited the timestep can be printed at the end of run using the star_job option show_timestep_limit_counts_when_terminate. Repeat the runs, adding/removing or adjusting timestep limits until there are few retries and few places where the timestep is limited by varcontrol. Finally, repeat the calculation with a smaller value of time_delta_coeff (e.g., 0.5) and compare the results to gain confidence that they are numerically converged.

### Module-level changes¶

#### astero¶

Material previously present in star/astero and test cases using these capabilities have been promoted into their own module.

The csound_rms observational constraint has been removed.

The options for executing an arbitrary shell script (shell_script_num_string_char and shell_script_for_each_sample) have been removed. The usual use for these options—renaming output files at the end of each sample—can be replicated using the system tools available through utils_lib. For example, the following extras_after_evolve in run_star_extras.f90 moves the best profile and FGONG file to outputs/sample_#.{profile,fgong}.

subroutine extras_after_evolve(id, ierr)
use astero_def
use utils_lib, only: mv
integer, intent(in) :: id
integer, intent(out) :: ierr
character (len=256) :: format_string, num_string, basename
ierr = 0

write(format_string,'( "(i",i2.2,".",i2.2,")" )') num_digits, num_digits
write(num_string,format_string) sample_number+1 ! sample number hasn't been incremented yet
basename = trim(sample_results_prefix) // trim(num_string)
call mv(best_model_fgong_filename, trim(basename) // trim('.fgong'), skip_errors=.true.)
call mv(best_model_profile_filename, trim(basename) // trim('.profile'), skip_errors=.true.)

end subroutine extras_after_evolve


#### auto_diff¶

This new module provides Fortran types that support algorithmic differentiation via operator overloading. Users will not generally need to interact with this module, but it can be used within run_star_extras to make derivatives easier to calculate (e.g. in the implicit hooks like other_surface).

Usage is by writing use auto_diff. This imports types such as auto_diff_real_4var_order1, which supports first-order derivatives with respect to up to four independent variables. A variable of this type could be declared via:

type(auto_diff_real_4var_order1) :: x


This variable then holds five fields: x%val stores the value of x. x%d1val1 stores the derivative of x with respect to the first independent variable. x%d1val2 is the same for the second independent variable, and so on. All d1val_ fields are initialized to zero when the variable is first set.

Once an auto_diff variable it initialized, all mathematical operations can be performed as they would be on a real(dp) variable. auto_diff variables also interoperate with real(dp) and integer types.

So for instance in the following f%d1val1 stores df/dx and f%d1val2 stores df/dy.

x = 3d0
x%d1val1 = 1d0

y = 2d0
y%d1val2 = 1d0

f = exp(x) * y + x + 4


Similar types are included supporting higher-order and mixed-partial derivatives. These derivatives are accessed via e.g. d2val1 (d²f/dx²), d1val1_d2val2 (d³f/dx dy²).

#### const¶

The const module has been updated to account for the revision of the SI and now uses CODATA 2018 values of the physical constants.

For astronomical constants, MESA follows IAU recommendations. MESA adopts nominal solar and planetary quantities from IAU 2015 Resolution B3 and now follows the recommended procedure of deriving nominal solar and planetary masses from the mass parameters $$(GM)$$ and the adopted value of $$G$$.

As a result of these changes, most constants now have slightly different values than in previous MESA versions. For example, $${\rm M}_\odot$$ changed from 1.9892e33 g to 1.9884e33 g.

#### eos¶

EOS-related options have been moved into their own eos namelist. The module controls and their default values are contained in the file eos/defaults/eos.defaults.

The PTEH EOS has been removed. Tables from the FreeEOS project now provide coverage of similar conditions.

The region covered by the PC EOS has been increased. The boundaries of the region where PC is used no longer consider composition and so now include H/He-dominated material. The upper limit of the region where PC is used is now determined using the electron Coulomb coupling parameter and generally corresponds to higher temperatures than the previous approach.

For more information about the component EOSes and the regions in which they are applied, see the new overview of the EOS module.

#### kap¶

Opacity-related options have been moved into their own kap namelist. The module controls and their default values are contained in the file kap/defaults/kap.defaults.

The OPAL Type 2 opacity tables are now on by default (use_Type2_opacities = .true.). These tables separately account for carbon and oxygen enhancements. Since this is especially important during core helium burning, the default transition from the OPAL Type 1 tables to the Type 2 tables occurs when material becomes nearly hydrogen free. As a result of this change, by default, users are required to specify the base metallicity of material using the kap namelist control Zbase. Usually, this physically corresponds to the initial metallicity of the star.

For more information about the opacity tables and how they are combined, see the new overview of the kap module.

#### rates & net¶

A number of rates have had their defaults switched to using JINA’s REACLIB.

When using a custom user rate (i.e from a rate table) the reverse rate is now computed in detailed balance from the user rate. Previously the reverse rate was computed using the default rate choice.

A bug with burning li7 at low temperatures rate has been fixed. Users stuck using previous versions of MESA and a soft network (something that is not an approx net) should add these lines to their nuclear network as a fix until they can update to a newer MESA:

remove_reaction(r_h1_li7_to_he4_he4)


With thanks to Bradley Munson for the bug report.

We now define the forward reaction to always be the exothermic reaction, not the reaction as defined by REACLIB. This fixes an issue with exothermic photo-disintegrations which would generate wrong values when computed in detailed balance.

A lot of work has been done getting operator split burning (op_split_burn = .true.) to work. This option can provide a large speed up during advanced nuclear burning stages. See the various split_burn test cases for examples.

### Other changes¶

• Saved model files now contain a version_number field in their header. This indicates the version of MESA that was used to generate the model.
• binary now automatically writes photo (restart) files at the end of the run.
• If not provided with an argument, the binary ./re script will now restart from the most recent photo (determined by filesystem modification time). The star ./re script also has this behavior as of r12778.
• The test case for building C/O white dwarf models has been overhauled to be more robust. See documentation for the new version in make_co_wd.
• The builder for NS envelopes (test case neutron_star_envelope) has been replaced with a more general envelope builder (test case make_env). The test cases ns_{h,he,c} have been overhauled to start from these new models.
• Added other_remove_surface. This routine is called at the start of a step and returns an integer k. All cells with j < k will be removed from the model at the start of the step, making cell k the new surface.
• Installations are now blocked from using sudo. This is generally not what you want to use to fix installation issues. If you want to install MESA in a root location then you will need to edit out the check in the install file.
• The install script now blocks attempts to use a MESA_DIR which contains spaces in it. This has never really worked as makefiles can not handle the spaces. To work round this either move MESA_DIR to a folder location with no spaces in its path or symlink your MESA_DIR to another location with no spaces in its path and set MESA_DIR to point at the symlink.
• The option to create a pre main sequence model now relaxes the model until a radiative core forms. This is activated with the star_job option pre_ms_relax_to_start_radiative_core, which can be set to .false. to restore the old behavior.

### Acknowledgments¶

Thanks to all who reported problems and asked or answered questions on mesa-users. Special thanks to Siemen Burssens, Mathias Michielsen, Joey Mombarg, Mathieu Renzo, and Samantha Wu for their assistance in testing pre-release versions.

## Changes in r12778¶

This section describes changes that occurred since r12115.

### SDK changes (Version 20.3.1 or later required)¶

To use the this MESA release, you must upgrade your SDK to 20.3.1.

In previous releases of MESA, we have included the CR-LIBM library to provide versions of standard math functions (exp, log, sin, etc) that guarantee correct rounding of floating-point numbers. In this new release, we made the decision to move CR-LIBM into the software development kit (SDK), where it properly belongs and can be maintained as one of the pre-requisites of MESA.

This means that to use this release (and subsequent releases) of MESA, you’ll need to upgrade to version 20.3.1 of the SDK or later. MESA checks the SDK version during compilation, and will stop with an error message if the SDK is too old.

### Backwards-incompatible changes¶

#### Replacement of crlibm_lib with math_lib¶

MESA now talks to CR-LIBM via an intermediate module called math_lib. To make sure any code you add can properly access the CR-LIBM math routines, you’ll need to make sure that a use math_lib statement appears in the preamble of the file. At the same time, you should remove any use crlibm_lib statements, as they will no longer work (and are not needed). With math_lib, the names of the correctly rounded math functions are the same as the Fortran intrinsics (i.e., they no longer have a _cr suffix).

Existing run_star_extras, run_binary_extras, or other user-written code will need to be updated. To migrate, you should replace use crlibm_lib with use math_lib and remove the _cr suffix from any math functions (e.g., exp_crexp).

#### Removal of DT2 and ELM EOS options¶

The ELM and DT2 EOS options have been removed. (These options were underpinned by HELM and OPAL/SCVH data, but used bicubic spline interpolation in tables of lnPgas, lnS, and lnE as a way to get numerically accurate 1st and 2nd partial derivatives with respect to lnRho and lnT. A more detailed description can be found in previous release notes and Appendix A.1 of MESA V.) These options were introduced in r10398 and were turned on by default in r11532.

The numerical issues that ELM/DT2 were designed to address have been dealt with via another approach. MESA now separately treats quantities that appear in the equations (and happen to be partials) and the places where these theoretically equivalent, but numerically different quantities appear in the Jacobian (as partials of other quantities that appear in the equations). This is an implementation detail that should be transparent to users.

This change has two pleasant side effects. One, it lowers the memory demands of many MESA models, which should aid users of virtualized, containerized, or otherwise memory-constrained systems. Two, it removes small, interpolation-related wiggles that were present in partial derivative quantities such as $$\Gamma_1$$.

These changes may require inlists that made use of DT2/ELM related options to be updated.

The following controls options have been deleted:

• use_eosDT2
• max_logT_for_max_logQ_eosDT2
• max_logQ_for_use_eosDT2
• use_eosELM
• logT_max_for_ELM
• logQ_min_for_ELM
• check_elm_abar_zbar
• check_elm_helm_agreement

The following star_job options have been renamed:

• eosDT2PTEH_use_linear_interp_for_X to eosPTEH_use_linear_interp_for_X

The following controls options have been renamed/removed, as well as moved to star_job (see next entry):

• logRho_max_for_all_PTEH_or_DT2 to logRho_max_for_all_PTEH
• logRho_max_for_any_PTEH_or_DT2 to logRho_max_for_any_PTEH
• logQ_max_for_low_Z_PTEH_or_DT2 (removed)
• logQ_max_for_high_Z_PTEH_or_DT2 to logQ_max_for_PTEH

#### Change in location of PTEH EOS options¶

Options that modify the parameters associated with the PTEH EOS have be moved from controls to star_job. This brings PTEH in line with the behavior of the other component EOSes.

If you explicitly set any of following options in your inlist, you will need to move them from controls to star_job. Their meaning and default values remain unchanged.

• use_eosPTEH_for_low_density
• use_eosPTEH_for_high_Z
• Z_for_all_PTEH
• Z_for_any_PTEH
• logRho_min_for_all_OPAL
• logRho_min_for_any_OPAL
• logRho_max_for_all_PTEH
• logRho_max_for_any_PTEH

In addition, you must add the new option set_eosPTEH_parameters = .true. to star_job to indicate that these values should override the eos module-level defaults.

The removal of DT2 (see previous entry) has also resulted in the change that the controls option logQ_max_for_low_Z_PTEH_or_DT2 has been removed (as it applied primarily to DT2) and logQ_max_for_high_Z_PTEH_or_DT2 (which applied primarily to PTEH) has been renamed to logQ_max_for_PTEH and moved from controls to star_job.

#### New overshooting controls¶

The new controls for overshooting, briefly described in the release notes of version 12115, are now the default in MESA (and the old controls have been removed). All test_suite cases now use these new controls.

There are two schemes implemented in MESA to treat overshooting: a step overshoot scheme and an exponential scheme that follows Herwig (2000).

The old “double exponential overshoot scheme” is no longer accessible through simple controls. An example of how to implement such a scheme via the other_overshooting_scheme hook is contained in the other_physics_hooks test suite case.

The new overshooting controls are based on convection-zone and convection-boundary matching criteria. In the new set of controls, for each convective boundary it is possible to define an overshoot_zone_type, overshoot_zone_loc and an overshoot_bdy_loc, as well as values for the overshooting parameters.

The permitted values are the following:

• overshoot_scheme = exponential, step
• overshoot_zone_type = burn_H, burn_He, burn_Z, nonburn, any
• overshoot_zone_loc = core, shell, any
• overshoot_bdy_loc = bottom, top, any

The following controls assign values for the diffusive or step overshooting parameters:

• overshoot_f
• overshoot_f0
• overshoot_D0
• overshoot_Delta0

overshoot_f0 is defined so that the switch from convective mixing to overshooting happens at a distance overshoot_f0*Hp into the convection zone from the estimated location where grad_ad = grad_rad, where Hp is the pressure scale height at that location.

For exponential overshoot, D(dr) = D0*exp(-2*dr/(overshoot_f*Hp0) where D0 is the diffusion coefficient D at point r0, Hp0 is the scale height at r0.

For step overshoot: overshooting extends a distance overshoot_f*Hp0 from r0 with constant diffusion coefficient D = overshoot_D0 + overshoot_Delta0*D_ob where D_ob is the convective diffusivity at the bottom (top) of the step overshoot region for outward (inward) overshooting.

These “new” controls replace the following “old” controls:

• overshoot_f_above_nonburn_core
• overshoot_f0_above_nonburn_core
• overshoot_f_above_nonburn_shell
• overshoot_f0_above_nonburn_shell
• overshoot_f_below_nonburn_shell
• overshoot_f0_below_nonburn_shell
• overshoot_f_above_burn_h_core
• overshoot_f0_above_burn_h_core
• overshoot_f_above_burn_h_shell
• overshoot_f0_above_burn_h_shell
• overshoot_f_below_burn_h_shell
• overshoot_f0_below_burn_h_shell
• overshoot_f_above_burn_he_core
• overshoot_f0_above_burn_he_core
• overshoot_f_above_burn_he_shell
• overshoot_f0_above_burn_he_shell
• overshoot_f_below_burn_he_shell
• overshoot_f0_below_burn_he_shell
• overshoot_f_above_burn_z_core
• overshoot_f0_above_burn_z_core
• overshoot_f_above_burn_z_shell
• overshoot_f0_above_burn_z_shell
• overshoot_f_below_burn_z_shell
• overshoot_f0_below_burn_z_shell
• step_overshoot_f_above_nonburn_core
• step_overshoot_f_above_nonburn_shell
• step_overshoot_f_below_nonburn_shell
• step_overshoot_f_above_burn_h_core
• step_overshoot_f_above_burn_h_shell
• step_overshoot_f_below_burn_h_shell
• step_overshoot_f_above_burn_he_core
• step_overshoot_f_above_burn_he_shell
• step_overshoot_f_below_burn_he_shell
• step_overshoot_f_above_burn_z_core
• step_overshoot_f_above_burn_z_shell
• step_overshoot_f_below_burn_z_shell
• step_overshoot_D
• step_overshoot_D0_coeff

The “new” control overshoot_D_min replaces the “old” control D_mix_ov_limit.

The “new” control overshoot_brunt_B_max replaces the “old” control max_brunt_B_for_overshoot.

The “new” control overshoot_mass_full_on replaces the “old” control mass_for_overshoot_full_on.

The “new” control overshoot_mass_full_off replaces the “old” control mass_for_overshoot_full_off.

The following example will apply exponential overshoot, with f = 0.128 and f0 = 0.100, at the bottom of non-burning convective shells; and exponential overshoot, with f = 0.014 and f0 = 0.004, at all other convective boundaries.

overshoot_scheme(1) = 'exponential'
overshoot_zone_type(1) = 'nonburn'
overshoot_zone_loc(1) = 'shell'
overshoot_bdy_loc(1) = 'bottom'
overshoot_f(1) = 0.128
overshoot_f0(1) = 0.100

overshoot_scheme(2) = 'exponential'
overshoot_zone_type(2) = 'any'
overshoot_zone_loc(2) = 'any'
overshoot_bdy_loc(2) = 'any'
overshoot_f(2) = 0.014
overshoot_f0(2) = 0.004


Other examples are illustrated in the test_suite cases. Examples for exponential overshooting can be found in the following test_suite cases:

• 1.4M_ms_op_mono
• 25M_pre_ms_to_core_collapse
• 5M_cepheid_blue_loop/inlist_cepheid_blue_loop
• 7M_prems_to_AGB/inlist_7M_prems_to_AGB
• accretion_with_diffusion
• agb
• axion_cooling
• black_hole
• c13_pocket
• cburn_inward
• envelope_inflation
• example_ccsn_IIp
• example_make_pre_ccsn
• gyre_in_mesa_rsg
• high_mass
• high_z
• hot_cool_wind
• magnetic_braking
• make_co_wd
• make_metals
• ppisn
• pre_zahb

Examples for step overshooting can be found in the following test_suite cases:

• high_rot_darkening
• relax_composition_j_entropy

#### Version number¶

The MESA version_number is now represented as a string internally and in the headers of history/profile output. User scripts that assume this is an integer may need to be revised.

#### other_wind hook¶

The interface of the other_wind hook changed from

subroutine other_wind_interface(id, Lsurf, Msurf, Rsurf, Tsurf, w, ierr)
use const_def, only: dp
integer, intent(in) :: id
real(dp), intent(in) :: Lsurf, Msurf, Rsurf, Tsurf ! surface values (cgs)
real(dp), intent(out) :: w ! wind in units of Msun/year (value is >= 0)
integer, intent(out) :: ierr
end subroutine other_wind_interface


to

subroutine other_wind_interface(id, Lsurf, Msurf, Rsurf, Tsurf, X, Y, Z, w, ierr)
use const_def, only: dp
integer, intent(in) :: id
real(dp), intent(in) :: Lsurf, Msurf, Rsurf, Tsurf, X, Y, Z ! surface values (cgs)
real(dp), intent(out) :: w ! wind in units of Msun/year (value is >= 0)
integer, intent(out) :: ierr
end subroutine other_wind_interface


Existing user routines will need to be updated.

#### Removal of id_extra from run_star_extras.f¶

Most routines in run_star_extras.f had an argument id_extra. This argument generally did not do anything and so has been removed. Existing user routines will need to be updated.

A simple way to migrate from routines written for previous versions of MESA is to find and replace the string “, id_extra” with the empty string in run_star_extras.f.

#### Change of extras_startup from function to subroutine¶

The interface of extras_startup changed from integer function to subroutine. The current empty version of this routine is:

subroutine extras_startup(id, restart, ierr)
integer, intent(in) :: id
logical, intent(in) :: restart
integer, intent(out) :: ierr
type (star_info), pointer :: s
ierr = 0
call star_ptr(id, s, ierr)
if (ierr /= 0) return
end subroutine extras_startup


Existing user routines will need to be updated to reflect this new interface.

#### Hooks for extra header items¶

The interface of the routines

• how_many_extra_history_header_items
• data_for_extra_history_header_items
• how_many_extra_profile_header_items
• data_for_extra_profile_header_items

has changed. If these routines are included in your run_star_extras.f (even if they have not been customized), you will need to update them. You should replace the old versions with:

integer function how_many_extra_history_header_items(id)
integer, intent(in) :: id
integer :: ierr
type (star_info), pointer :: s
ierr = 0
call star_ptr(id, s, ierr)
if (ierr /= 0) return

subroutine data_for_extra_history_header_items(id, n, names, vals, ierr)
integer, intent(in) :: id, n
character (len=maxlen_history_column_name) :: names(n)
real(dp) :: vals(n)
type(star_info), pointer :: s
integer, intent(out) :: ierr
ierr = 0
call star_ptr(id,s,ierr)
if(ierr/=0) return

! here is an example for adding an extra history header item
! names(1) = 'mixing_length_alpha'
! vals(1) = s% mixing_length_alpha

integer, intent(in) :: id
integer :: ierr
type (star_info), pointer :: s
ierr = 0
call star_ptr(id, s, ierr)
if (ierr /= 0) return

subroutine data_for_extra_profile_header_items(id, n, names, vals, ierr)
integer, intent(in) :: id, n
character (len=maxlen_profile_column_name) :: names(n)
real(dp) :: vals(n)
type(star_info), pointer :: s
integer, intent(out) :: ierr
ierr = 0
call star_ptr(id,s,ierr)
if(ierr/=0) return

! here is an example for adding an extra profile header item
! names(1) = 'mixing_length_alpha'
! vals(1) = s% mixing_length_alpha



#### Removal of inlist_massive_defaults¶

The file inlist_massive_defaults has been removed from star. Copies of the inlist can now be found in the following test cases:

• 25M_pre_ms_to_core_collapse
• 25M_z2m2_high_rotation
• black_hole
• envelope_inflation
• example_ccsn_IIp
• example_make_pre_ccsn
• magnetic_braking
• split_burn_20M_si_burn_qp
• split_burn_big_net_30M
• split_burn_big_net_30M_logT_9.8

### Other changes¶

• The routines {alloc,move,store,unpack}_extra_info were removed from standard_run_star_extras.inc. (These routines were used to store/retrieve information from photos.) If you have existing run_star_extras code that includes these routines, it will continue to function. However, in new run_star_extras code, the recommended way to store/retrieve data is using the other_photo_read and other_photo_write hooks. Examples can be found in the conductive_flame and brown_dwarf test suite cases.
• The controls xtra_coef_os_* and xtra_dist_os_* which could be used to modify mesh_delta_coeff in overshooting regions have been removed. The same functionality is available using the other_mesh_delta_coeff_factor and an example implementation is given in the agb test suite case.
• The output-related control alpha_bdy_core_overshooting and related history options core_overshoot_{Hp,f,f0,hstep,r0} and {mass,radius}_bdy_core_overshooting have been removed.
• The star_data module was split out of the star module. The source file describing the contents of the star_info data structure is now located at star_data/public/star_data.inc.
• If not provided with an argument, the ./re script will now restart from the most recent photo (determined by filesystem modification time).
• Added star_control pre_ms_relax_to_start_radiative_core to existing star_control pre_ms_relax_num_steps to provide option for creating a pre-main sequence model just after the end of the fully convective period. The relaxation steps from raw pre-ms model to end of fully convective are done using simple control setting selected for robustness. After the relaxation is complete, the actual inlist parameter settings are used.
• Added a new hook other_accreting_state to allow the user to specify the specific total energy, pressure, and density of the accreting material. These properties are used by eps_mdot to compute the contribution of accretion to the energy equation. By default (when this hook is not used), these properties are all taken from the surface cell.