Chris Savage: Research

My area of research is cosmology/particle astrophysics. This includes (among other things):

My main focus is on dark matter detection phenomenology, specifically for particle dark matter candidates.

Various observations—such as the galaxy rotation curves, the cosmic microwave background, gravitational lensing, and structure formation—suggest that most of the matter in the universe is composed of something other than ordinary matter (e.g. protons, neutrons, and electrons). This missing matter, which rarely (if ever) interacts with ordinary matter (except gravitionally) and is therefore hard to see, is called "dark matter".

One candidate for this dark matter is a new particle(s), which must have three properties: it is stable, it is massive, and it only weakly interacts with ordinary matter. Many fundamental particles (quarks, leptons, neutrinos, photons, W & Z bosons, and the higgs particle) and composite particles (hadrons and mesons) have been discovered. While some of these satisfy two of the conditions for a dark matter particle, none satisfy all three. However, new particles are continually being discovered and we expect that there are many more to come.

If the dark matter is composed of such particles, we can hope to identify those particles three ways: direct detection, indirect detection, and production in accelerators. Though interactions with ordinary matter are rare, the dark matter in our galaxy will occasionally collide with nuclei (or electrons, depending on the dark matter particle) and cause the nuclei to recoil. Direct detection experiments aim to find these rare recoils occurring within a detector. Dark matter particles may also occasionally collide with each other and annihilate, the energetic products being particles we are more familiar with like gamma-rays, electrons, and protons. By identifying anomalous sources of cosmic rays produced by annihilating dark matter, we can indirectly detect the presence of these dark matter particles. Finally, these particles may be produced in high-energy collisions of ordinary matter, such as occurs in accelerators like the LHC. Such collision events will have unique signatures, primarily missing energy as the dark matter particles will escape the detector without interaction, carrying away some of the collision energy.

My CV and publications may be found by following the links to the left.