Preliminaries#
The mesagrid package uses outputs from MESA and GYRE. Let’s install them! An installation script can be found here.
Once the installation script is finished, you should see:
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MESA installation was successful
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Hooray! You are ready to get started.
Your first MESA run#
Let’s copy a fresh work directory over:
cp -R $MESA_DIR/star/work .
cp -R $MESA_DIR/star/defaults/*.list work
cd work
./mk
./rn
That should have worked. If so, we’re ready to compute some models for asteroseismology.
For a slower pace of the installation and the following tutorial, see the recorded tutorial here.
Let’s change the mass, initial chemical composition, and mixing length parameter so that we roughly get a solar-like model. You can copy over the values from my inlist given in the src/ directory. I have also instructed MESA to output FGONG whenever a profile file is generated.
Let’s also uncomment delta_nu and nu_max from history_columns.list, and brunt_N and lamb_S from profile_columns.list.
Now when we run this we should get some output in the LOGS directory. Let’s analyze that with python now.
Compute frequencies with GYRE#
Now let’s calculate some frequencies. An example GYRE inlist awaits you in the src/ directory. Copy that over to your LOGS/ directory and run it with GYRE:
cp ../src/gyre.in LOGS
cd LOGS
$GYRE_DIR/bin/gyre gyre.in
I’ve prepared a script in the src/ directory that will allow us to efficiently obtain the frequencies of all our stellar models. Let’s run that in a loop:
for FGONG in *.FGONG; do
../../src/gyre6freqs.sh -i $FGONG -f
done
or even better, using xargs in parallel:
find . -name "*.FGONG" -print0 | xargs -0 -P 8 -I{} ../../src/gyre6freqs.sh -i {} -f -t 1
A small grid#
Let’s now try to run a grid of tracks with different masses. We’ll begin by copying our work over to a new directory and removing the logs files:
cp -R work grid
cd grid
rm -rf LOGS
Now let’s edit inlist_project to stop the run at a central hydrogen fraction of 0.1, and also specify the log_directory = '1' in the &controls block.
Afterwards, we are ready to use shmesa to run a small grid of models:
mkdir grid
for M in 0.7 0.8 0.9 1.0 1.1 1.2; do
echo "Running mass $M"
shmesa change inlist_project initial_mass $M
shmesa change inlist_project log_directory "grid/M_'$M'"
./star inlist_project
cd $M
for GYRE in *.GYRE; do
../../src/gyre6freqs.sh -i $FGONG -f -t $OMP_NUM_THREADS
done
cd -
done