Add a TZO test case

Author: rjfarmer

docs/source/test_suite.rst

@@ -485,6 +485,12 @@ This test checks the counter and timing routines with a 1.5 Msun, Z=0.02 metalli
 This test case exercise the capability to simultaneously evolve two model stars.
 The test vehicle is a pair of 15 Msun, Z=0.02 metallicity, models one with overshooting and one without overshooting.
 
+
+:ref:`tzo`
+^^^^^^^^^^
+
+This test case creates a Thorne-Zytkow object (TZO) and evolves until the NS has accreted a small amount of material.
+
 :ref:`wd_c_core_ignition`
 ^^^^^^^^^^^^^^^^^^^^^^^^^
 

docs/source/test_suite/tzo.rst

@@ -0,0 +1 @@
+../../../star/test_suite/tzo/README.rst

star/test_suite/do1_test_source

@@ -96,6 +96,7 @@ do_one wd_nova_burst "have finished burst" "final.mod" auto
 do_one wd_stable_h_burn "stop because star_mass >= star_mass_max_limit" "final.mod" auto
 do_one high_rot_darkening "termination code: xa_central_lower_limit" "final.mod" auto
 
+do_one tzo "PASS: Have reached requested NS mass" "final.mod" auto
 
 # return
 

star/test_suite/tzo/.gitignore

@@ -0,0 +1,6 @@
+final.prof
+pre_tzo.mod
+post_tzo.mod
+tzo.mod
+Grid1
+

star/test_suite/tzo/README.rst

@@ -0,0 +1,21 @@
+.. _tzo:
+
+***
+TZO
+***
+
+This test case builds and evolves a Thorne-Zytkow object (TZO) (Farmer et al in prep)
+
+The model stats by building a 20 |Msun| star mid way through the main sequence (inlist_initial). The precise physics do not matter here,
+but having a large convective burning core is necessary for the the TZO formation to proceed smoothly.
+
+inlist_initial_make then moves the inner boundary to a desired inner mass and radius, assumed for the NS. It is helpful to have some
+assumed energy injection at this point in time (core_avg_eps).
+
+inlist_initial_post_relax then alters the total mass of the TZO and the composition to match the required starting values. While relax_Z does change the total
+metal mass fraction, it does not change the metal distribution. Thus you may want to use relax_composition_filename instead to have complete control of the composition.
+
+inlist_evolve_tzo then evolves the TZO for as long as possible. For the test suite the end condition if the NS sufficient mass via Eddington limited accretion.
+With this check removed the end condition is when the surface begins undergoing large amplitude pulsations and we can no longer follow the evolution
+(this usually occurs around v_surf/v_escape ~ 40%). Note that as the NS will accrete at Eddington limited rates (10^-8 Msun/yr) it grows very little over the typical
+lifetime of a TZO, thus you should not use the test suite ending condition for actual science.

star/test_suite/tzo/ck

@@ -0,0 +1,7 @@
+#!/bin/bash
+
+# this provides the definition of check_one
+# check_one
+source "${MESA_DIR}/star/test_suite/test_suite_helpers"
+
+check_one

star/test_suite/tzo/clean

@@ -0,0 +1,2 @@
+cd make
+make clean