So you just copy the inlist as it is, into your working directory, and
you can run the 15Msun solar metallicity model until the depletion of
oxygen in the core with very simple few changes. Before doing that
right away I encourage you guys to check each of the star_job and
control parameters in:

/mesa/star/defaults/

so that you have some idea of what kind of changes have been made to
the default input physics. The important ones for this specific model
are:

 the control of the C12(alpha,gamma)O16 reaction rate- 
      set_rate_c12ag = 'Buchmann'
      num_special_rate_factors = 1
      reaction_for_special_factor(1) = 'r_c12_ag_o16'
      special_rate_factor(1) = 1.2

the control of the C12+C12 reaction rate-
      set_rate_1212 = 'CF88'  ! one of 'CF88' or 'G05'
      num_special_rate_factors = 2
      reaction_for_special_factor(2) = 'r1212_to_ne20'
      special_rate_factor(2) = 1.0

Niewunhuijzen mass loss scheme- 
      RGB_wind_scheme = 'Nieuwenhuijzen'
      AGB_wind_scheme = '' 
      RGB_to_AGB_wind_switch = 1d-4
      Nieuwenhuijzen_wind_eta = 1.0d0

and convection physics (overshooting and semiconvection control)-
      mixing_length_alpha = 2.0

      use_Ledoux_criterion = .true.
      alpha_semiconvection = 0.1

      overshoot_f_above_burn_h = 0.025
      overshoot_f_above_burn_he = 0.025
      overshoot_f_above_nonburn = 0.025
      overshoot_f_below_nonburn = 0.025
      overshoot_f_above_burn_z = 0.025
      min_overshoot_q = 1d-3 

To do your project on this massive star model, you will need model
snapshots at several stages of evolution to make some plots and
analyses. One way to do this is through these stopping criteria in the
controls section-

!hedep
!      xa_central_lower_limit_species(1) = 'he4'
!      xa_central_lower_limit(1) = 0.01
!cign
!      log_center_temp_limit = 8.69897 !0.5d8K
!cdep
!      xa_central_lower_limit_species(1) = 'c12'
!      xa_central_lower_limit(1) = 0.01
!oign
!      log_center_temp_limit = 9.204 !1.6d9K
!odep
      xa_central_lower_limit_species(1) = 'o16'
      xa_central_lower_limit(1) = 0.05

these are the stopping conditions. hedep = core helium depletion;
cign=ignition of carbon in the core; cdep=depletion of carbon in the
core; oign=ignition of oxygen in the core and odep=depletion of oxygen
in the core. Notice that the actual criteria are not all the same for
each evolutionary stage, i.e. for some it is the abundance of some
species at the center, but at others it is the value of the central
temperature.

In the inlist you see that the !odep criteria are left open,
everything else is commented out with "!". If you run this inlist
right away as it is, then it will stop right after creating the pre_MS
model. Why? because the O16 abundance is smaller than >0.05 when the
star starts evolving on the main sequence. So first thing you want to
do is - comment out the odep condition and uncomment the hedep, like
this:

hedep
      xa_central_lower_limit_species(1) = 'he4'
      xa_central_lower_limit(1) = 0.01
!cign
!      log_center_temp_limit = 8.69897 !0.5d8K
!cdep
!      xa_central_lower_limit_species(1) = 'c12'
!      xa_central_lower_limit(1) = 0.01
!oign
!      log_center_temp_limit = 9.204 !1.6d9K
!odep
!      xa_central_lower_limit_species(1) = 'o16'
!      xa_central_lower_limit(1) = 0.05

so now the model will run until the depletion of Helium in the core
and stop. During the mesa calculation the code saves model snapshots
(profile files) and restart dumps (x files) according to the interval
you specified in the controls, and it also saves one profile and x
when it stops, no matter of the interval. If you look at the terminal
output of your run, at the end you'll see something like this:

save LOGS/profile22.data for model 1577
save photos/x977 for model 1577

this means the hedep condition was reached at 1577th timestep and the
snapshot model at the core helium depletion is saved in the LOGS/
directory as profile22.data; and the restart dump at this stage is
saved in the photos/ directory as x977.  So now you want to save this
snapshot, otherwise it will be overwritten later on:

cp LOGS/profile22.data hedep_data

also saving the restart dump might be handy just in case things go
wrong:

cp photos/x1577 photos/hedep_restart

Now you have the snapshot at hedep, and let's say you want your next
snapshot at cign. First you want to edit the stopping criteria
accordingly:

hedep
!      xa_central_lower_limit_species(1) = 'he4'
!      xa_central_lower_limit(1) = 0.01
!cign
      log_center_temp_limit = 8.69897 !0.5d8K
!cdep
!      xa_central_lower_limit_species(1) = 'c12'
!      xa_central_lower_limit(1) = 0.01
!oign
!      log_center_temp_limit = 9.204 !1.6d9K
!odep
!      xa_central_lower_limit_species(1) = 'o16'
!      xa_central_lower_limit(1) = 0.05

I have commented out hedep and uncommented cign criteria. You don't
need to run the whole thing from the start, instead you can just use
the restart dump at hedep and run it from there:

./re hedep_restart

be careful, the command is ./re here, not ./rn. When you press enter,
the code will run from hedep until cign, should be quite fast. After
its done, do the same exercise - save the last snapshot and restart
dump.

Obviously these stopping conditions are here just to guide you. You
should feel free to invent your own and play with it yourself. The
model snapshots - profileXX.data files - are simple ASCI tables. It
would be a good exercise for you to try to write a simple routine to
read the data from these tables. If you face trouble, let me know, I
have many scripts for all kinds of things.

Finally, a portion of your assignment will ask you to plot data not
from one single snapshot, but the changes throughout the
evolution. Such data are stored also in the LOGS/ directory, but the
file name is:

LOGS/history.data

this is also an ASCI table, very similar to the profileXX.data.

That's it for now, please feel free to get in touch with me about any of this.

Tuguldur