The second part of Yorick Van Den Bossche’s master’s thesis, star formation and stellar feedback, has been added to the public repository. To this end, a third type of particle was added to the code, which acts very similar as a dark matter particle, but also keeps track of its age. Star formation can be activated by setting a new flag in the parameter file. When star formation is active, gas particles are converted into star particles if they meet three star formation criteria: they have to be cold enough, dense enough, and need to be in a region of converging flow.
Star particles can also give feedback to the surrounding gas, if the appropriate parameter is set. They give three different types of feedback: early, purely energetic feedback of stellar winds, SNII feedback consisting of a large amount of energy and metals, and SNIa feedback which happens with a significant delay with respect to the other feedback types. For all types, the feedback energy and mass is deposited into the cell that contains the star particle, i.e. the gas particle that is closest in space to the star particle.
Currently, no test for the star formation or feedback is provided in the testsuite, and there are still some problems when combining star formation and feedback with radiative cooling and self-gravity. These problems will be solved in future commits.
Yorick Van Den Bossche’s master thesis can be found online.