Events at Physics
Events During the Week of September 18th through September 25th, 2011
- Plasma Physics (Physics/ECE/NE 922) Seminar
- A 24/7 tokamak: the Vulcan conceptual design
- Time: 12:05 pm
- Place: 2317 Engineering Hall
- Speaker: Dennis Whyte, A 24/7 tokamak: the Vulcan conceptual design
- Chaos & Complex Systems Seminar
- Bees: What is all the buzz about?
- Time: 12:05 pm
- Place: 4274 Chamberlin
- Speaker: Hannah R. Gaines, UW Department of Entomology
- Abstract: One in every three bites we eat is dependent on pollinators. Bees, the most important pollinators, however, are in decline around the world. Historically, farmers have relied upon one species, the non-native honey bee (Apis mellifera) for their pollination requirements. In recent years, however, honey bees have declined drastically as a result of mites, disease, and the recent emergence of Colony Collapse Disorder (CCD). As CCD continues to spread and devastate honey bee colonies, farmers will need to seek alternative ways of pollinating their crops. Native bees also provide valuable pollination services but have largely been overlooked and are at risk of decline due to habitat fragmentation, intensified agriculture, and agri-chemical exposure. In this seminar I will talk about the current status of pollinators, their importance to world agriculture, and our research addressing the importance of native pollinators and their response to landscape structure.
- Host: Clint Sprott
- Department Meeting
- Time: 12:15 pm
- Place: 5310 Chamberlin Hall
- Astronomy Colloquium
- "Tails of Stellar Mass Loss: The HI 21-cm Line as a Probe of the Late Stages of Stellar Evolution"
- Time: 3:30 pm
- Place: 4421 Sterling Hall
- Speaker: Lynn Matthews, MIT Haystack Observatory
- Abstract: As they near the end of their lives, low-to-intermediate mass stars undergo copious mass-loss, leading to the formation of extensive circumstellar envelopes (CSEs) up to a parsec or more across. These envelopes are a primary source of dust and heavy element enrichment in the Galaxy, affect the structure of the interstellar medium on small scales, and are precursors to the formation of planetary nebulae. I will present results from a program aimed at improving our understanding of the evolutionary histories of mass-losing giants through a previously little-used probe of circumstellar material: the HI 21-cm line of neutral hydrogen. Because HI is not destroyed by the interstellar radiation field, it can trace CSEs to significant distances from the star, thereby probing mass-loss over very extended timescales (>100,000 years). HI also supplies unique kinematic information on the interaction between CSEs and their environments. Our results to date include the discovery of extended tails, bow shocks, and other structures associated with well-known evolved stars as well as new constraints on mass-loss timescales. We have recently expanded our HI studies to Cepheid variables, and I will also report on implications for mass-loss on the Cepheid instability strip as a means of resolving the long-standing "Cepheid mass discrepancy".
- Host: Professor John S Gallagher
- Graduate Introductory Seminar
- High Energy Collider Experiment Seminar
- Time: 5:30 pm
- Place: 2223 Chamberlin Hall
- Speaker: Carlsmith, Dasu, Herndon, Mellado, Pan, Smith, Wu
- Cosmology Journal Club
- An Informal discussion about a broad variety of arXiv papers related to Cosmology
- Time: 12:00 pm
- Place: 5242 Chamberlin Hall
- Abstract: This week we'll discuss...
Papers that have not yet been determined
Please feel free to bring your lunch!
If you have questions or comments about this journal club, would like to propose a topic or volunteer to introduce a paper, please email Le Zhang (firstname.lastname@example.org).
- Host: Peter Timbie
- Theory Seminar (High Energy/Cosmology)
- The Matrix Element Method for Higgs Discovery and Spin Determination
- Time: 2:00 pm
- Place: 5280 Chamberlin
- Speaker: Jamie Gainer, Argonne National Laboratory and Northwestern U.
- Abstract: Multivariate Analyses (MVA) have become important tools for experimentalists in recent years. A particular MVA, the Matrix Element Method (MEM) uses full differential cross section information in determining the event by event likelihood. We examine the extent to which the use of the MEM allows one to increase the significance for Higgs discovery in various channels where the Higgs decays to gauge bosons which in turn decay leptonically. We additionally consider the use of the MEM for spin discrimination in these channels.
- Physics Department Colloquium
- Recent Results from CMS at LHC
- Time: 3:30 pm
- Place: 2241 Chamberlin Hall (coffee at 4:30 pm)
- Speaker: Sridhara Dasu, University of Wisconsin-Madison
- Abstract: The Large Hadron Collider is operating at 7 TeV center of mass energy for the past two years, delivering good quality data. The CMS experiment has established the Standard Model at this energy and has embarked on new physics searches. Early results from the searches for higgs bosons, supersymmetry and other exotic new physics will be presented. The emphasis will be on the contributions from the University of Wisconsin team.
- Host: Smith