Abstract: The extreme densities reached by matter in neutron stars makes these compact objects compelling laboratories in which to study nuclear physics under conditions that can not currently be reproduced terrestrially. In particular, the isospin asymmetry of neutron star matter is promising for studies of the nuclear symmetry energy, and neutron star cores may be dense enough for exotic phases of matter to appear. However, current probes of neutron star structure mainly provide constraints on bulk quantities such as mass and radius. These quantities can be highly informative to the equation of state of the neutron star core, but do not reliably constrain its composition or the properties of matter found in the star's solid crust. Instead, a more powerful tool with which to probe the interior composition of these objects is asteroseismology: the study of quasi-normal modes and their oscillations. Different modes are sensitive to different properties of matter in different regions of the star, and so can provide more detailed information than can be obtained from bulk stellar properties alone. 

In this seminar, I will provide an overview of neutron star quasi-normal modes and their connection to the structure and composition of neutron star matter. I will discuss the nuclear physics which could be studied in neutrons stars, and the modes which may be sensitive to it. I will then present my work on resonant shattering flares. These flares are a possible explanation for 'precursors' observed shortly before some short gamma-ray bursts, and are the result of resonant excitations of quasi-normal modes in the neutron star crust shortly before binary neutron star mergers. I will show that the multimessenger detection of a resonant shattering flare alongside gravitational waves would provide a strong constraint on the frequency of the crust-core interface mode, and that this in turn constrains the nuclear symmetry energy. These findings will then be discussed in the context of nuclear theory and experiment results.