Marie Vidal
Stanford University

Abstract

I am fascinated by studying neutrinos because despite being the most abundant particle in the universe, our knowledge about them is limited. Key elements about the neutrinos, like their mass and place in the Standard Model are still unknown today. The observation of neutrino oscillations, which is possible only if neutrinos have mass, was the first hint of physics beyond the Standard Model. One proposed mechanism to explain the neutrinos’ small mass compared to other fermions, is that neutrinos could be Majorana particles, meaning that the neutrino is its own antiparticle. The question of whether the neutrino is a Majorana particle could explain the origin of the asymmetry between matter and antimatter we observe today. The nEXO experiment will search for neutrinoless double beta (0νββ) decay using a 5-tonne liquid xenon (LXe) time projection chamber (TPC), enriched to 90 % in 136Xe, with a projected half-life sensitivity > 1028 years after 10 years of data. With a general overview of the nEXO experiment, I will present the R&D efforts lead by the nEXO collaboration to maintain our sensitivity goal. I am also interested in coherent elastic neutrino-nucleus scattering, or CEνNS, because of the science we can learn from it. Coherent elastic neutrino-nucleus scattering provides a new observable that is a neutral current to detect neutrinos. This neutral current interaction is flavor blind, so we can detect all neutrino flavors, even the neutrinos that oscillated to another flavor! It can be used as a tool to study remaining discrepancies in reactors (5 MeV) and Gallium anomalies, and probe for the existence of a fourth sterile neutrino. NEWS-G (New Experiments With Spheres-Gas) is a rare event search experiment using Spherical Proportional Counters (SPCs). Primarily designed for the direct detection of dark matter, this technology also has appealing features for CEνNS studies. A study to assess the feasibility of observing CEνNS at a nuclear reactor will be presented. Both direct dark matter detection and CEνNS consist of nuclear recoils from elastic scatters. The calibration to nuclear recoils is primordial for both searches. I will present the experimental method and analysis framework that were used to extract the first calibration to neon nuclear recoils in neon gas.

Timbits, coffee, tea will be served in STI A before the colloquium.

Ana Botti
University of Chicago

Abstract

In recent years, advancements in theoretical frameworks motivated searches for light-dark matter particles in the meV-GeV mass region by showing the compatibility of these models with cosmological observations. New emerging technologies, such as skipper-CCDs, facilitated the development of small- and medium-sized experiments tailored for exploring these theoretical models. Skipper-CCDs are pixeled silicon detectors with a deep sub-electron resolution that allows the detection of eV energy transfers, such as that expected from light-dark matter interacting with electrons in a silicon target. SENSEI is the first experiment to use skipper-CCD for this purpose and to produce world-leading results using this technology. In this talk, I present an overview of the SENSEI experiment and the current status after successfully commissioning the second science run at SNOLAB. I will also discuss the prospects in rare-events searches with skipper-CCDs: from SENSEI’s 100 g detector to OSCURA’s 10 kg array and more.

Timbits, coffee, tea will be served in STI A before the colloquium.

Maximilian Swiatlowski
TRIUMF

Abstract

The discovery of the Higgs boson at the Large Hadron Collider completed the Standard Model, but many fundamental open questions in particle physics remain. One question is particularly simple: how could the Big Bang produce the matter-dominated universe we observe without anti-matter, which should have been produced in equal parts? As the LHC produces collisions faster than ever before, the huge datasets the ATLAS experiment is collecting can provide answers to this question, and others, by enabling the measurement of the extremely rare production of pairs of Higgs bosons. Though difficult to observe, these signatures can directly measure the shape of the Higgs potential: deviations from the Standard Model's expectations could allow us to understand not just the history of the early universe that created the matter/anti-matter asymmetry, but questions like the future stability of the universe. This talk will focus on the challenges to detecting Higgs boson pairs, and how to interpret them to understand the true shape of the Higgs potential and consequences for physics beyond the Standard Model. The latest results from the ATLAS experiment will be presented, and prospects for future measurements at the High-Luminosity LHC and next-generation colliders will be discussed.

Timbits, coffee, tea will be served in STI A before the colloquium.

Mark Chen
Queen's University

Abstract

TBA

Timbits, coffee, tea will be served in STI A before the colloquium.

Cao Zhen
Institute of High Energy Physics, Beijing; Tianfu Cosmic Ray Research Center, Chengdu

Abstract

LHAASO has discovered PeVatrons in the Milky Way. The first Cosmic Ray Super-PeVatron is found in the Cygnus region with 8 photons above 1 PeV pile-up in a so-called cosmic ray bubble of 10°. A couple of PWNe are found emitting photons up to 2 PeV. They pose challenges by manifesting so-called "Extreme Accelerators" in our galaxy. In future, we need to improve the spatial resolution to carry out deep investigations for the mechanism. Detection of Neutrinos from the PeVatrons will put in the last piece of the big puzzle lasted for a century.

Timbits, coffee, tea will be served in STI A before the colloquium.

Karen Lee-Waddell
Director, Australian SKA Regional data Centre (AusSRC)
Karen is alumna of Queen’s University

Abstract

I will present an overview of the amazing telescopes that drew this Canadian girl to a continent where kangaroos outnumber humans. I will include details about my research work with neutral hydrogen (HI) and fast radio busts (FRBs). I will also cover recent SKA Observatory (SKAO) and SKA Regional Centre (SRC) activities.

Hydrogen is the fuel for star-formation and comprises majority of the baryonic matter in our Universe. Using radio telescopes such as ASKAP and eventually the SKA, HI is readily detectable in and around galaxies, giving information about the composition, dynamics, and evolutionary history of these galactic systems.

FRBs are extremely energetic and particularly peculiar astronomical events arising from unknown origins. As more FRBs are detected and localised to host galaxies, we are starting to constrain the environments that could trigger these millisecond pulses. Several FRBs have been localised to extragalactic systems that are close enough for HI observations and further detailed analysis shedding light on these mysterious events.

The SKAO is an intergovernmental project to build the world’s largest radio telescopes. In order to fully exploit the scientific output of the immense amount (~700 PB / year) of data flowing from the Observatory, international cooperation through nationally lead hubs -- referred to as SRCs -- is required. The Australian SKA Regional Centre (AusSRC) is part of this global computing and data delivery network that will enable ground-breaking science by providing the connection between the SKA telescopes and the scientific community.

Timbits, coffee, tea will be served in STI A before the colloquium.