Dark matter searches beyond the WIMP: pushing sensitivities with skipper-CCDs

Date

Monday November 11, 2024
2:30 pm - 3:30 pm

Location

STI 501

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.

 

 

 

How Pairs of Higgs Bosons Help Us Understand the Standard Model and Beyond

Date

Friday November 8, 2024
1:30 pm - 2:30 pm

Location

STI A

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

Date

Friday November 1, 2024
1:30 pm - 2:30 pm

Location

STI A

Mark Chen
Queen's University

 

Abstract

TBA

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

 

 

Cosmic-Ray Super-PeVatrons and Extreme Accelerators

Date

Friday October 4, 2024
1:30 pm - 2:30 pm

Location

STI A

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.

 

 

Radio astronomy in the land ‘down under’ – ASKAP, SKA, and the AusSRC

Date

Friday October 25, 2024
1:30 pm - 2:30 pm

Location

STI A

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.

 

 

Physics Students Receive German DAAD RISE Research Scholarships

This previous summer two Queen’s University Engineering Physics students were awarded Research Internships in Science and Engineering (RISE) Scholarships from the German Academic Exchange Service (DAAD). The scholarships, sponsored by Queen’s University and Mathematics of Information Technology and Complex Systems (Mitacs), provided students Simon Bronkhorst-Ilavsky and Ciaran Byles-Ho with the opportunity to participate in research-based internships in Germany.

Article Category

Radiation in Galaxy Formation and Evolution:  A tale of 7 dwarfs

Date

Friday November 15, 2024
1:30 pm - 2:30 pm

Location

STI A

James Wadsley
McMaster University

 

Abstract

Galaxies are not as isolated as they may appear: they exchange huge amounts of material with their nearby environment.  Even typical disk galaxies contain only 1/4 the expected stars and gas (baryons) expected from their dark matter.   Smaller galaxies can contain far less.    These exchanges have many consequences, such as polluting nearby space with hot gas and metals, which can be observed as quasar absorption lines out to large distances.   There is a long list of ideas for how galaxies limit their gas and star content,  including pushing gas out with stellar feedback such as supernovae,  AGN, cosmic rays and radiation driven processes.     Violent outflows even have the potential to modify the dark matter profile.  There are also more subtle mechanisms, such as not letting the gas cool and accrete in the first place.   I present recent simulations using on-the-fly radiative transfer to better model gas in and around galaxies and the consequences for their evolution. I show the impact on dwarf galaxies in particular.

 

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