Events at Physics |
Events During the Week of February 25th through March 4th, 2018
Monday, February 26th, 2018
- Council Meeting
- Place: 2314 Chamberlin Hall
- Plasma Physics (Physics/ECE/NE 922) Seminar
- nitial Results on the Impact of Background Hydrogen Isotope on Impurity Behavior in the EC-heated LHD plasmas
- Time: 12:05 pm
- Place: 2241 Chamberlin Hall
- Speaker: Prof. N. Tamura, NIFS (National Institute for Fusion Science) at the Graduate University for Advanced Studies (SOKEDAI) in Japan.
- NPAC (Nuclear/Particle/Astro/Cosmo) Forum
- Understanding CP-Violation in Leptons
- Time: 3:30 pm
- Place: 4274 Chamberlin Hall
- Speaker: Daniel Cherdack, Colorado State University
- Abstract: Of the four known fundamental forces the weak force has many unique properties. It is the only standard model force that couples to all known fermions, that has massive exchange bosons, and that induces particle flavor changes. Even more surprising is that the weak force maximally violates parity symmetry, and has even been demonstrated to break charge-parity (CP) symmetry, meaning the weak force interacts differently with matter and anti-matter. This last property may hold the key to understanding several fundamental mysteries of the universe from the three-generation structure of matter, to the missing link between the big bang and the observed universe.
Neutrinos only interact via the weak force which means they are hard to detect, but provide a unique test bed for studying the weak interaction. Over the past few decades it was discovered that neutrinos have mass and change flavors. Studying the way neutrinos change flavors, termed neutrino oscillations, allows us to search for a new source of CP-violation. Measuring and understanding the ways neutrinos interact with nuclear matter is key to studiying neutrino oscillations and has proved to be more difficult than previously thought. The next-generation Deep Underground Neutrino Experiment (DUNE) will usher in an era of high precision neutrino physics with the worlds most intense neutrino beam and massive high resolution detectors, increasing the impact of neutrino interaction measurements. I will discuss the theoretical framework we use to describe neutrino oscillations, as well as the difficulties in making neutrino interaction measurements and how they can be mitigated moving forward. - Host: Sridhara Dasu
Tuesday, February 27th, 2018
- Chaos & Complex Systems Seminar
- Thoughts on drumlins, a major component of Wisconsin's glacial landscape
- Time: 12:05 pm - 1:00 pm
- Place: 4274 Chamberlin (Refreshments will be served)
- Speaker: David Mickelson, UW Department of Geology
- Abstract: Thousands of cigar-shaped elongate hills dominate the landscape to the east and north of Madison. Produced by glaciers 15,000 to 25,000 years ago, they have a range of heights from meters or less to several hundred meters and have distinctly different length-to-width ratios in different areas. All are parallel to former ice flow direction. They are composed of sediments deposited by the last glaciation, but many also contain older deposits. Why are they so abundant in Wisconsin, but absent from the huge areas covered by the last glaciation in most of Illinois, Indiana, Iowa, and Ohio?
- Host: Clint Sprott
- "Physics Today" Undergrad Colloquium (Physics 301)
- Exploring the High-Energy Universe with HAWC
- Time: 1:20 pm - 2:10 pm
- Place: 2241 Chamberlin Hall
- Speaker: Stefan Westerhoff, UW Madison Department of Physics
- Host: Wesley Smith
Wednesday, February 28th, 2018
- Department Meeting
- Time: 12:15 pm
- Place: 5310 Chamberlin Hall
Thursday, March 1st, 2018
- NPAC (Nuclear/Particle/Astro/Cosmo) Forum
- What's New with the Pierre Auger Observatory
- Time: 2:30 pm
- Place: 5280 Chamberlin Hall
- Speaker: Corbin Covault , Case Western Reserve University
- Abstract: We present an update of selected results and recent activities and plans for the Pierre Auger Observatory. Located near Malargue, Argentina, Auger is the world's largest cosmic ray air shower array. Auger has recently reported a significant detection of large scale anisotropy in the arrival direction of the highest energy cosmic rays. We also describe recent efforts to integrate spectral and composition measurements and what these results tell us about the nature and origin of cosmic ray sources. We address some points of tension between results reported by Auger and those of the Telescope Array (TA), and describe a project involving our group at CWRU to obtain an in-situ cross-calibration between Auger and TA surface detector stations. Finally we describe progress toward the development of the array detector upgrade, called AugerPrime, which aims for improved composition measurements.
- Host: Justin Vandenbroucke
Friday, March 2nd, 2018
- Physics Department Colloquium
- Exploring the dark universe with cosmic surveys
- Time: 3:30 pm
- Place: 2241 Chamberlin Hall
- Speaker: Keith Bechtol, Large Synoptic Survey Telescope
- Abstract: Over the past few decades, a “standard” but puzzling cosmological model has emerged that has passed increasingly stringent observational tests, and yet raises many new questions. What is causing the accelerated expansion of the Universe? What are the particle constituents of dark matter? Can we measure the influence of massive neutrinos on the growth of cosmic structure? The Dark Energy Survey (DES) is one of several ongoing experiments producing ever larger and more detailed maps of the night sky to address these questions via statistical inference from measurements of hundreds of millions of individual stars and galaxies. I will highlight several recent results from DES, including cosmology constraints from gravitational weak lensing, galaxy clustering, and supernovae, newfound dwarf galaxies and stellar streams, and the first optical detection of a kilonova explosion associated with a gravitational wave signal. I will conclude with a discussion of the next major experiment in this field, the Large Synoptic Survey Telescope (LSST), now under construction in Chile, with first light expected in 2020.
- Host: Sridhara Dasu