Events at Physics |
Events During the Week of August 18th through August 25th, 2024
Monday, August 19th, 2024
- Academic Calendar
- Faculty contract year begins
- Abstract: *Note: actual end time may vary.*
- Climate & Diversity
- Processing Space
- Climate and Diversity Processing Space
- Time: 1:00 pm - 3:00 pm
- Place: Chamberlin 5313
- Abstract: This will be entirely drop in and non-mandatory, and a space to talk about the impact this or other bias related events have had on you as an individual or the community as a whole.
- NPAC (Nuclear/Particle/Astro/Cosmo) Forum
- The Camera System and Tau Neutrino Research in the TRIDENT Experiment
- Time: 2:30 pm - 3:30 pm
- Place: WIPAC Supernova
- Speaker: Wei Tian, Tsung-Dao Lee Institute, Shanghai Jiao Tong University, China
- Abstract: Following the groundbreaking discovery and studies of astrophysical neutrinos by IceCube, TRIDENT has been proposed as a next-generation neutrino telescope, planned for construction at a depth of around 3,500 meters in the Western Pacific Ocean. It aims to enhance the search for astrophysical neutrino sources and optimize all-flavor neutrino detection. As a water-based neutrino telescope, TRIDENT faces unique challenges in optical calibration due to the time-varying and non-uniform optical properties of the dynamic water medium. In this talk, I will present a custom-designed CMOS camera system and its adaptive image processing algorithms for real-time optical calibration, which were successfully demonstrated in TRIDENT’s Pathfinder experiment in 2021. Looking ahead, tau neutrino identification is crucial for effective flavor separation in TRIDENT. I will also share the latest progress in tau classification, utilizing the double pulse algorithm and exploring the integration of Graph Neural Network techniques, based on the independent PMT waveform readout by TRIDENT's hDOM.
- Host: Francis Halzen
Tuesday, August 20th, 2024
- Theory Seminar (High Energy/Cosmology)
- Entanglement in String Theory
- Time: 2:00 pm - 3:30 pm
- Place: Chamberlin 5280
- Speaker: Upamanyu Moitra, The Abdus Salam International Centre for Theoretical Physics
- Abstract: The finiteness of entanglement entropy in string theory has crucial implications for the information paradox, quantum gravity, and holography. I will describe the recent progress made on establishing this finiteness based on an appropriate orbifold construction. I will describe how one can get a finite and calculable answer for the entanglement entropy in several diverse scenarios, including string compactifications, string theory on AdS3 and heterotic strings.
- Host: Gary Shiu
Wednesday, August 21st, 2024
- Preliminary Exam
- Characterizing the Diffuse Astrophysical Neutrino Flux from the Galactic Plane using IceCube Data
- Time: 2:00 pm - 4:00 pm
- Place: 5280 Chamberlin Hall
- Speaker: Jesse Osborn, Physics PhD Graduate Student
- Abstract: IceCube has detected high energy neutrinos from the galactic plane of the Milky Way galaxy at a significance of 4.5 sigma, establishing evidence for the Milky Way as a source of neutrinos. Now, I investigate the extent to which we can characterize the diffuse flux from the Milky way using a combination of IceCube datasets and present my plan for the analysis. I will also discuss my work developing a new event selection for the real-time neutrino alerts that IceCube sends out to the multi-messenger astrophysics community.
- Host: Albrecht Karle
Thursday, August 22nd, 2024
- Thesis Defense
- Available Energy and Slow Eigenmodes for Understanding Moisture and Phase Changes in Atmospheric Physics
- Time: 10:00 am - 12:00 pm
- Place: 5280 Chamberlin -
- Speaker: Brad Kumm, Physics Graduate Student
- Abstract: In atmospheric physics, clouds and moisture are some of the greatest challenges. They are the leading source of uncertainty in climate change predictions, and rainfall is arguably the most challenging quantity to predict in weather forecasts. In addition, theoretical understanding of moisture in the atmosphere lags behind the understanding of a dry atmosphere. To increase our theoretical understanding of moisture in the atmosphere this work focuses on two concepts: (i) Energy, and in particular Available Potential Energy (APE), and (ii) slow eigenmodes. The first results presented center around a new decomposition of APE for a compressible, adiabatic atmosphere with phase changes, and shows that it can be decomposed into acoustic and buoyant pieces, which are present in dry decompositions, as well as a new slow "latent" piece which accounts for a parcel changing between saturated, and unsaturated states. Second, a method is presented to account for moisture in a global atmospheric decomposition framework, by splitting it into an Inertio-gravity piece, a Rossby piece, and an additional "slow" piece which accounts for a large fraction of the total atmospheric moisture. Finally, such a decomposition is performed using global moisture data, in what may be the first moist decomposition of this kind, in order to quantify the relative contributions of each of these pieces.
- Host: Samuel Stechmann, Jan Egedal
- Preliminary Exam
- Line Intensity Mapping: A Novel Technique to Measure Large Scale Structure and Galaxy Evolution
- Time: 2:00 pm - 4:00 pm
- Place: B343, Sterling Hall
- Speaker: Sam Kramer, Physics PhD Graduate Student
- Abstract: Understanding the formation and development of the Universe's large scale structure (LSS) is the primary goal of cosmology. The earliest stage of the Universe has been well-measured via the cosmic microwave background, and traditional, large-spectrum surveys have mapped the most recent epochs. Line intensity mapping (LIM) is a novel technique that seeks to fill in the billions of years of evolution in between. LIM experiments record the atomic/molecular transition line emissions of common galactic constituents from many galaxies at once, requiring less integration time and lower resolutions to efficiently map LSS over a broad range of redshifts. The EXperiment for Cryogenic Large-Aperture Intensity Mapping (EXCLAIM) is a LIM pathfinding mission that seeks to measure the [CII] emission line of ionized carbon at redshifts 2.5 to 3.5, corresponding to a period in the Universe with the highest rates of new star formation. [CII] is believed to be a tracer of both star formation and the large scale structure of the universe, but current empirical models for this relationship vary across orders of magnitude. Using simulations and existing survey data, we can develop cross-correlation techniques like the cross power spectrum, stacking, and the conditional voxel intensity distribution to predict [CII] detection at high SNRs and constrain the [CII] emission models with EXCLAIM.
- Host: Peter Timbie
Friday, August 23rd, 2024
- Academic Calendar
- Graduate School Summer 2024: Master's degree deadline
- Time: 11:55 pm - 12:55 am
- Abstract: CONTACT: 262-2433, gsacserv@grad.wisc.edu
Saturday, August 24th, 2024
- No events scheduled
Sunday, August 25th, 2024
- Academic Calendar
- Graduate School Summer 2024: Doctoral degree deadline
- Time: 11:55 pm - 12:55 am
- Abstract: CONTACT: 262-2433, gsacserv@grad.wisc.edu