Conveners
Particle Physics
- Thomas Brunner (McGill/TRIUMF)
Particle Physics: exotic atoms and fundamental symmetries
- Derek Fujimoto
Particle Physics: Dark Matter/Rare Decays/High Energy Physics
- Zisis Papandreou (U Regina)
The ATLAS detector has been at the frontier of high energy physics, gathering data from proton-proton collisions at the LHC for more than a decade. The instantaneous luminosity of the Large Hadron Collider at CERN will be increased up to a factor of five to seven with respect to the design value for the High Luminosity LHC. Several sub-systems of the ATLAS detector will be upgraded in order...
New Long-lived particles (LLPs) - ones that could travel long distances before decaying- are among numerous exotic signatures that would help address the universe’s biggest mysteries such as Dark Matter. Many Beyond the Standard Model theories that aim to address the limitations of the standard model point to the Higgs boson as a possible portal to new physics, where the Higgs successively...
According to the standard model, all flavours of leptons have equal couplings to gauge bosons - this is called lepton flavour universality. However, recently, experiments such as LHCb and Muon g-2 have reported findings, which suggest that this may not be the case, i.e. lepton flavour universality violation may occur. One way to explain these anomalies is through new particles called...
I present a new, open-source program, MUTE (MUon inTensity codE), which propagates cosmic ray muons from the atmosphere to laboratories deep underground and underwater using the most recent state-of-the-art computational tools. The evolution of cosmic rays in the Earth's atmosphere is computed with MCEq (Matrix Cascade Equation), using the latest theoretical primary and hadronic interaction...
A bubble chamber using fluorocarbons or liquid noble gases is a competitive technology to detect a low-energy nuclear recoil due to elastic scattering of weakly interacting massive particle (WIMP) dark matter. It consists of a pressure and temperature-controlled vessel filled with a liquid in the superheated state. Bubble nucleation from liquid to vapor phase can only occur if the energy...
The discrete-discrete atomic form factor is calculated for two non-equal masses of particles. The integral involving the product of Bessel functions and associated Laguerre polynomials is used to calculate the radial integral. An explicit analytical expression for the discrete-discrete transition form factor is presented exactly in the way they are implemented in the program. This atomic form...
Antihydrogen, the simplest atomic antimatter system, is an excellent platform to search for matter-antimatter asymmetries. The kinetic energy (and thus velocity) of synthesized antihydrogen trapped in the laboratory setting is very large relative to the energy well depth of the trap providing the confining force. Accuracy of any measurements performed on trapped antihydrogen, and the...
The ALPHA (Antihydrogen Laser PHysics Apparatus) collaboration aims to test fundamental symmetries with matter and antimatter by testing CPT (charge conjugation, parity reversal, time reversal) theory and observing whether antimatter follows Einstein’s Weak Equivalence Principle (WEP), where the acceleration due to gravity that a body experiences is independent of its structure or composition....
The ALPHA project is a cornerstone of the effort to verify symmetries between matter and antimatter, with implications for understanding the baryon asymmetry and the evolution of our universe. The new ALPHA-g experiment aims to perform the first precision measurement the acceleration of anti-hydrogen atoms at rest in a gravitational field, a key piece of this puzzle.
This measurement...
It has been known for many years that an electron and its antiparticle, the positron, may together form a metastable hydrogen-like atom, known as positronium or Ps. In 1946, Wheeler speculated that two Ps atoms may combine to form the positronium molecule (Ps) stable with respect to auto-dissociation. In 2007 the existence of Ps was confirmed experimentally.
I will present a determination of...
The TUCAN (TRIUMF Ultra-Cold Advanced Neutron) Collaboration aims to build a new, intense source of ultracold neutrons (UCN). The first experimental use of the TUCAN source will be to complete a world-leading measurement of the neutron electric dipole moment (nEDM), the discovery of which would support the search for new sources of CP violation beyond the Standard Model. Neutrons will be...
Despite the success of the Standard Model of particle physics, there are still phenomena such as dark matter that it doesn't explain. New particles light enough to be created at accelerators could resolve many of these issues, but could exist anywhere across a very wide range of masses and behaviours. Physicists are using many different experiments to search for them, each optimised for a...
Potassium-40 ($^{40}$K) is a naturally-occurring, radioactive isotope of interest to rare-event searches as a challenging background. In particular, NaI scintillators contain $^{40}$K contamination which produces an irreducible $\sim 3\text{ keV}$ signal originating from this isotope's electron capture (EC) decays. In geochronology, the $\mathcal{O}(\text{Gy})$ lifetime of $^{40}$K is utilized...
The New Small Wheel (NSW) detectors have recently been added to the ATLAS muon end-cap system. The detector is composed of two technologies: Micromegas (MM) and small-strip Thin Gap Chambers (sTGC). The sTGCs are fast tracking detectors that will allow ATLAS to veto fake muons and maintain a low trigger threshold. An sTGC quadruplet is composed of four gas volumes where an individual gas...
A network of 15 pixelated detectors based on Timepix ASICs was installed in ATLAS cavern to measure the Radiation Field composition and Luminosity during CERN-LHC Run 2. The Timepix detectors are capable of measuring Luminosity with 5 different algorithms namely Cluster Counting Algorithm, Hit Counting Algorithm, Total Deposited Energy Algorithm, Thermal Neutron Counting Algorithm and MIPs...
The most commonly produced objects in the ATLAS detector are jets, streams of particles spreading out from the proton-proton collision point. Jets develop from the constituent quarks and gluons of the protons. These particles carry color charge, and as such cannot exist freely under QCD confinement, and a chain reaction of quark/gluon production begins. Eventually, the quarks and gluons...
