B_s-anti-B_s Mixing in Z' Models with Flavor-Changing Neutral Currents

In models with an extra U(1)' gauge boson family non-universal couplings to the weak eigenstates of the standard model fermions generally induce flavor-changing neutral currents. This phenomenon leads to interesting results in various B meson decays, for which recent data indicate hints of new physics involving significant contributions from b -> s transitions. We analyze the B_s system, emphasizing the effects of a Z' on the mass difference and CP asymmetries.Comment: 16 pages, 3 figures; references added, submitted to Phys. Lett.

Logarithmic Growth of Dikes From a Depressurizing Magma Chamber

Dike propagation is an intrinsically multiphase problem, where deformation and fluid flow are intricately coupled in a fracture process. Here we perform the first fully coupled simulations of dike propagation in two dimensions, accounting for depressurization of a circular magma chamber, dynamic fluid flow, fracture formation, and elastic deformation. Despite the complexity of the governing equations, we observe that the lengthening is well explained by a simple model a(t) = c₁ log(1 + t/c₂), where is the dike length, is time, and c₁ and c₂ are constants. We compare the model to seismic data from eight dikes in Iceland and Ethiopia, and, in spite of the assumption of plane strain, we find good agreement between the data and the model. In addition, we derive an approximate model for the depressurization of the chamber with the dike length. These models may help forecast the growth of lateral dikes and magma chamber depressurization

Overview of the 84th Annual UCEA Conference: Blurring the Boundaries of the Academy

To meet the challenges of the next century, continuing higher education is recreating itself to assume position of campus-wide leadership. Traditional continuing education units that were simply the university\u27s off-campus course providers are using their organizational flexibility to take on innovative and expanded roles that include for-profit distance learning centers, international educational partnerships, welfare-to-work initiatives, and post-baccalaureate programs for the changing workforce. While maintaining the academy\u27s high standards of scholarship and research, continuing education is also being asked to become a lead voice in conceiving the new academy and in linking the university to the demands of society. These new roles and initiatives are resulting in unprecedented growth and a reconfiguration of the academy\u27s traditional relationships