Events at Physics |
Events on Friday, April 17th, 2009
- Theory/Phenomenology Seminar
- Implications of a Scalar Dark Force for Terrestrial Experiments
- Time: 2:30 pm
- Place: 5280 Chamberlin Hall
- Speaker: Sonny Mantry, UW-Madison Physics Dept.
- Abstract: Does Dark Matter (DM) fall at a different rate than ordinary matter under gravity? Such a violation of the Weak Equivalence Principle (WEP) could arise
through ultralight scalars mediating a new long range "dark force" between DM particles. Such scenarios can arise, for example, through DM-quintessence
interactions or in non-universal scalar-tensor theories of gravity invoked to explain aspects of dark energy. The presence of a dark force would affect galactic dynamics, the CMB spectrum, and large scale structure formation typically requiring it to be weaker than gravity. Furthermore, a dark force will be communicated to ordinary matter through quantum effects as long as the DM is not sterile. This allows one to further probe dark forces through terrestrial experiments such as Eotvos tests of the WEP, DM-direct-detection experiments, and collider signals. - Physics Department Colloquium
- Neutrino Physics Beyond SNO
- Time: 4:00 pm
- Place: 2241 Chamberlin Hall (coffee and cookies at 3:30 pm)
- Speaker: Mark Chen, Queen's University
- Abstract: A follow-up experiment to the Sudbury Neutrino Observatory is being developed, called SNO+. With a liquid scintillator replacing the heavy water, SNO+ will examine neutrino phenomena at lower energies than SNO. Physics goals include: detecting the CNO solar neutrinos and using them to resolve a new puzzle related to solar chemical composition; precision measurements of the survival probability of pep solar neutrinos at the transition energy between vacuum- and matter-dominated oscillation; and measuring the flux of geo-neutrinos in a detector site where the local geology has been extensively characterized, enabling the measurement to address fundamental questions in geoscience. We also plan to add neodymium to the SNO+ liquid scintillator in order to perform a competitive next-generation 0-nu double beta decay search. The physics capabilities and the status of the experiment will be presented.
- Host: Heeger