Summer Seminar Series: Michael Butler

Please join us this Tuesday, July 3 in Physics 175 at 3:30 pm for our next presentation in our PEGASUS Summer Seminar Series.
Our next speaker is Michael Butler:

Quantum Gravity, the AdS/CFT Correspondence, and Self-Dual Spacetimes

Michael Butler

Quantum gravity represents the efforts of several fields in physics to find a unified description of gravity that operates on all scales. The Anti-de Sitter space/conformal field theory (AdS/CFT) correspondence, or gauge/gravity duality, is the observation that some mappings exist between quantum field theories to specific descriptions of gravity under general relativity. In an endeavour to better understand these dualities metrics from M-theory are derived. These metrics describe a spacetime which can be examined to understand how that quantum representation of gravity behaves under Einstein’s field equations. Self-dual metrics are of particular interest as they  represent these dualities in concise mathematical terms. This enables us to examine the associated gravitational models in useful test cases, such as blackholes, where quantum and gravitational physics converge. This talk will go over the concepts of gauge/gravity duality with a focus on self-dual metrics and their importance in establishing the connection between quantum and gravitational theories.

Summer Seminar Series: Ethan Runge

Please join us today at 3:00 pm in Physics 175 for our next presentation in our PEGASUS Summer Seminar Series.
Our next speaker is Ethan Runge:

Creating LIFE in the Lab

Ethan Runge

The Limb Imaging FTS Experiment (LIFE) Version 1 prototype balloon instrument is entering the build phase of the development cycle. LIFE makes use of an interferometer to take limb images of the atmosphere, to which a Fourier transform can be applied, to retrieve spectral information. Spectral information can then be used to determine atmospheric profiles of trace gas species; LIFE aims to obtain ozone, methane, water vapor nitrous oxide profiles. The system as it exists today is set-up in the lab for characterization and calibration purposes. A large amount of time and effort is required to get this design working, and this talk will focus on these tasks which must be completed, with a focus on detector characterization and uniform time sampling and their importance to instrument operation.

Summer Seminar Series: Gaelene Lerat

Please join us this Tuesday, June 5 in Physics 175 for our first presentation in our annual PEGASUS Summer Seminar Series.
Our first speaker is Gaelene Lerat:

The Search for the Substorm Current Wedge: A Comparison of SuperDARN and AMPERE Results

Gaelene Lerat

 

Near-Earth space is a region where the dynamics are best described by the motion of plasmas and the currents that flow there.  To understand the chain of events that leads to space weather phenomena, the connections of the interplanetary magnetic field to the magnetosphere to the ionosphere need to be understood.  In particular, during night side events called substorms currents flow along Earth’s magnetic field between the magnetosphere and the ionosphere. Incoming and outgoing field-aligned currents are part of the substorm current wedge that connects in the ionosphere and in the magnetosphere.  Two scientific tools are used to calculate field-aligned currents: the magnetometers aboard the Iridium satellite constellation in the AMPERE project, and the radar network SuperDARN.  A comparison between AMPERE and SuperDARN methods will be given, as well as the results for a superposed epoch analysis and spatial alignment for field-aligned current data of both instruments during substorm times in Earth’s ionosphere.

Call for physics student volunteer to represent Canada at May International event in Paris (via Canadian Association of Physicists)

International Day of Light 2018
ATTN: Physics Students at a Canadian University
The International Association of Physics Students (IAPS) has provided us with a unique opportunity to send a volunteer to the UNESCO-sponsored International Day of Light (IDL) celebration in Paris, France on May 16, 2018. The volunteer will help with exhibits and educational activities throughout the day. More information about the day can be found at https://www.lightday.org/. Accommodations for the delegate on the nights of May 15 and 16 will be covered as well as travel to and from Paris.
 
The CAP is accepting applications from students pursuing a Bachelor’s, Masters, or PhD degree in physics at an eligible Canadian university. The applicant should be comfortable with talking, in English, about the concepts of light with a general audience. Preference will be given to students who have taken a 2nd year or higher level optics course (please comment on this in your covering letter which will accompany your application). More information about eligibility and requested materials can be found in the attached application form.
 
Please note that the IAPS is aiming to have diverse representation in this international group of volunteers and so we encourage all interested physics students who meet the eligibility requirements to apply.
 
The application deadline is Wednesday, February 14th at 5:00pm CST. No late applications will be accepted.

Please submit applications by e-mail to Chris Pugh at ac.unodnarbnull@chgup.

If you have any further questions, don’t hesitate to contact Chris Pugh at ac.unodnarbnull@chgup.

Best,

Chris Pugh, CAP’s representative with the IAPS

Chitra Rangan, CAP’s International Day of Light Coordinator for Canada

[PEGASUS] Summer Seminar Series: Fraser Hird

Please join us this Tuesday, July 11 in Physics 175 for our next presentation in our PEGASUS Summer Seminar Series.
Our next speaker is Fraser Hird, who works with the ePOP-SuperDARN Experiment.
There will be cookies and refreshments served beforehand at 3:00 pm in the lounge for those attending the seminar.

Title: Measurements and Analysis of Polarization Data from the ePOP-SuperDARN Experiment.

Abstract: The Radio Receiver Instrument (RRI) onboard the enhanced Polar Outflow Probe (ePOP) consists of four 3-metre monopoles in an orthogonal dipole configuration used for observing the polarization of incoming High Frequency (HF) radio wave signals. Propagation of a wave through a ionized medium with an external magnetic field has notable effects on its polarization state through what is known as the Appleton-Hartree equation. Through conjunction with ground-sourced HF signals, RRI data leads to observations of structure in the ionosphere. In the framework of this research, the HF radio waves are sourced by the SuperDARN Saskatoon station. Scientific background and current RRI data results will be presented.

[PEGASUS] Summer Seminar Series: Kimberlee Dube

Please join us this Tuesday, July 4 in Physics 175 for our next presentation in our PEGASUS Summer Seminar Series.
Our next speaker is Kimberlee Dube, who studies ozone and aerosol profiles using OSIRIS.
There will be cookies and refreshments served beforehand at 3:00 pm in the lounge for those attending the seminar.
Title: The effect of solar rotation on OSIRIS ozone and aerosol observations 
Abstract:
The amount of solar radiation reaching the Earth’s atmosphere varies with both the 11 year solar cycle and the 27 day solar rotation period. The Optical Spectrograph and InfraRed Imager System (OSIRIS) has been in orbit on the Odin satellite since late 2001. The effect of solar UV variability on ozone and aerosol profiles retrieved from OSIRIS was investigated for a 14 year period. Current results will be presented and compared with those from other limb instruments.

[PEGASUS] Summer Seminar Series: Kimberlee Dube

Please join us Tuesday, July 4 in Physics 175 for our next presentation in our PEGASUS Summer Seminar Series.
Our next speaker is Kimberlee Dube, who studies ozone and aerosol profiles using OSIRIS.
There will be cookies and refreshments served beforehand at 3:00 pm in the lounge for those attending the seminar.
Title: The effect of solar rotation on OSIRIS ozone and aerosol observations 
Abstract:
The amount of solar radiation reaching the Earth’s atmosphere varies with both the 11 year solar cycle and the 27 day solar rotation period. The Optical Spectrograph and InfraRed Imager System (OSIRIS) has been in orbit on the Odin satellite since late 2001. The effect of solar UV variability on ozone and aerosol profiles retrieved from OSIRIS was investigated for a 14 year period. Current results will be presented and compared with those from other limb instruments.

[PEGASUS] Summer Seminar Series: Caelia Gardiner

Please join us this Tuesday, June 20 in Physics 175 for our next presentation in our PEGASUS Summer Seminar Series.
Our next speaker is Caelia Gardiner, who studies oxygen spectral emissions in the mesosphere and lower thermosphere.
There will be cookies and refreshments served beforehand at 3:00 pm in the lounge for those attending the seminar.
Title: Oxygen A Band Emission in the SaskTran Radiative Transfer Framework
Abstract:
Oxygen emission is a contributor to day glow in the mesosphere and lower thermosphere (MLT). The emissions occur in the atmospheric band of oxygen, which ranges from 629 nm to 762 nm, and corresponds to oxygen’s second electronic excited state. There are three vibrational levels within the atmospheric band, with the A band representing the lowest level. Emissions in the A band are centred around 762 nm and are the most significant contributor to oxygen emissions in the atmospheric band. The SaskTran radiative transfer framework is a software model that simulates light propagation through the atmosphere to produce radiance profiles. While it currently includes oxygen absorption in the A band, oxygen emission has yet to be implemented. Modelling the volume emission rate of oxygen molecules in the A band by use of HITRAN data and photochemical processes will provide the information necessary to simulate oxygen emission with SaskTran. This work is also done in support of the Swedish satellite MATS (Mesospheric Airglow/Aerosol Tomography and Spectroscopy), which will take optical measurements of mesospheric gases. Understanding the process of oxygen A band emission through simulation and measurement will improve scientific understanding of the MLT and provide valuable data for other atmospheric study.

[PEGASUS] Summer Seminar Series: William Elcock

Please join us this Tuesday, June 13 in Physics 175 for our next presentation in our PEGASUS Summer Seminar Series.
Our next speaker is William Elcock, who studies hysteresis in perovskite solar cells.
There will be cookies and refreshments served beforehand at 3:00 pm in the lounge for those attending the seminar
 
Title: Hysteresis in Perovskite Solar Cells
 
Abstract:
Perovskite solar cells have demonstrated power conversion efficiencies (PCEs) greater than 20%. However, current density-voltage (J-V) hysteresis (i.e. a difference in photocurrent between forward and reverse scans) makes it difficult to determine the true PCE of perovskite solar cells. The mechanism behind this hysteretic behaviour is not yet fully understood. However, the accumulation of halide ions at the perovskite active layer/contact interface has been put forward as a possible explanation behind this phenomenon. With this talk, I will give a background on hysteretic phenomena and the challenges posed by hysteresis in perovskite solar cells. I will also explain how the proposed ion migration mechanism results in hysteretic behaviour.