Relativistic charged particles, so-call cosmic rays, are the primary drivers of chemistry in molecular clouds in regions shielded from intense radiation. Cosmic rays affect molecular gas in numerous ways: charging dust grains, heating gas, and driving chemistry through ionizing molecular hydrogen (and other molecules). Typically, astrochemical models make very simple assumptions about the cosmic ray flux. I am working on implementing more sophisticated treatments of cosmic rays physics into astrochemical models. These cosmic ray-chemistry models provide more sensitive and accurate predictions on the abundances of molecules in star-forming regions.

Cosmic rays are produced by accelerating particles, most commonly protons, to significantly higher energies. For proton energies most important for chemistry, between 1 keV and 1 GeV, these particles lose energy rapidly as they travel into molecular clouds. Therefore, novel sources of these low-energy cosmic rays are being searched for! I have explored the acceleration of protons in the enegetic regions near newly forming, accreting stars, called protostars and their impact on chemistry. I have also proposed a novel source of these particles: acceleration in the ubiquitous turbulence within molecular clouds, which would provide a general source available for molecular chemistry.

Molecular data for chemical processes is of fundamental importance for astrochemical modelling. The importance of energetic particle interactions on gas- and ice-phase chemistry, from high-energy protons to low-energy electrons, necessitates as much high-fidelity molecular and atomic data for these interactions. I have initiated the Astrochemistry Low-energy electron Cross-Section (ALeCS) database with a collaboration between astronomers and chemists. The initial release includes molecular geometries, electron orbitals and ionization cross sections for over 200 molecules and atoms of astrochemical interest, along with ionization rates in both the UMIST and KIDA formats.

Short-lived radioactive nuclei (radionuclides) have half-lives of less than a few million years. Excess amounts of specific radioactive isotopes measured in meteorites indicate the early solar system was contaminated by a wide-range of radionuclides. These isotopes provide fingerprints of the galactic and protostellar environment during the formation of the solar system. Theoretical models typically explain this enrichment by supposing the existence nearby supernova or high-mass stars. I have recently proposed a novel local mechanism of isotope enrichment. My student and I are currently investigating how radioactive isotopes from supernova mix into cold, dense, star-forming gas.