The basics
A few of the ideas behind our work.
We study what unstable atoms can tell us about nature. These short explanations and videos are a place to start.
Jump to: Particles & forces · Neutrinos · Quantum sensors
What is radioactive decay?
An unstable atomic nucleus can transform spontaneously, releasing energy and particles. This is radioactive decay. Its predictable patterns make radioactive atoms useful tools for testing the laws of physics.
We focus on beta decay and electron capture. In electron capture, a proton in the nucleus combines with an atomic electron to become a neutron and emit a neutrino. The daughter atom receives a tiny kick, or recoil, that our experiments can measure.
What is the Standard Model?
The Standard Model describes the known elementary particles and their electromagnetic, weak and strong interactions. It makes extraordinarily successful predictions, but it does not explain everything—for example, the nature of dark matter or how gravity fits into the same framework.
What is the weak interaction?
The weak interaction is one of nature’s fundamental forces. It allows particles to change type and is responsible for beta decay and electron capture. Precision measurements of these decays test whether this interaction behaves as the Standard Model predicts.
Why study neutrinos?
Neutrinos have no electric charge and extremely small masses. They rarely interact with matter, so they usually leave an experiment without being detected. Their masses and properties still hold important unanswered questions.
We investigate these elusive particles by measuring what they leave behind. In electron capture, the daughter atom’s recoil depends on the neutrino’s mass. A careful measurement can test for additional, heavier neutrinos as well as reveal properties of the known ones.
How do we test for new physics?
We compare precise measurements with precise calculations. An unexpected result is a reason to investigate carefully: detector effects, conventional physics and theoretical uncertainties must be understood before it can be evidence for a new particle or interaction.
How do quantum sensors help?
Quantum sensors use quantum properties of matter to detect very small signals. In BeEST and SALER, we use superconducting sensors with radioactive atoms embedded inside them. Energy deposited by a decay becomes an electrical signal that can be measured precisely.
We are also exploring levitated optomechanics, where the signal is the tiny motion of a particle suspended in light. Each approach gives a different view of nuclear recoil.
Watch: quantum sensing
For a friendly introduction, watch Professor Chandrasekhar Ramanathan explain quantum sensing at five levels of difficulty in this WIRED video.
CONTACT
Philomena Abakah
Senior Program Officer – Research and Lab Operations
p.abakah@queensu.ca