Measurement of the B0-anti-B0-Oscillation Frequency with Inclusive Dilepton Events

The $B^0$-$\bar B^0$ oscillation frequency has been measured with a sample of 23 million \B\bar B pairs collected with the BABAR detector at the PEP-II asymmetric B Factory at SLAC. In this sample, we select events in which both B mesons decay semileptonically and use the charge of the leptons to identify the flavor of each B meson. A simultaneous fit to the decay time difference distributions for opposite- and same-sign dilepton events gives $\Delta m_d = 0.493 \pm 0.012{(stat)}\pm 0.009{(syst)}$ ps$^{-1}$.Comment: 7 pages, 1 figure, submitted to Physical Review Letter

Measurement of the CP-Violating Asymmetry Amplitude sin2β\beta

We present results on time-dependent CP-violating asymmetries in neutral B decays to several CP eigenstates. The measurements use a data sample of about 88 million Y(4S) --> B Bbar decays collected between 1999 and 2002 with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. We study events in which one neutral B meson is fully reconstructed in a final state containing a charmonium meson and the other B meson is determined to be either a B0 or B0bar from its decay products. The amplitude of the CP-violating asymmetry, which in the Standard Model is proportional to sin2beta, is derived from the decay-time distributions in such events. We measure sin2beta = 0.741 +/- 0.067 (stat) +/- 0.033 (syst) and |lambda| = 0.948 +/- 0.051 (stat) +/- 0.017 (syst). The magnitude of lambda is consistent with unity, in agreement with the Standard Model expectation of no direct CP violation in these modes

Recent developments in acacia planting: proceedings of an international workshop held in Hanoi, Vietnam, 27-30 October 1997

The 1300 species of the genus Acacia extend around the globe, from Australia through Asia to Africa and the Americas. These nitrogen-fixing trees and shrubs grow in a range of environments and fill an important niche in natural ecosystems. They have also been planted as exotics in over 70 countries for land rehabilitation, shade and shelter, and to produce a range of wood and non-wood products including firewood, charcoal, building poles, tannins and fodder. In recent years extensive plantations have been established in Asia to provide wood pulp for paper and textile manufacture. This book contains 52 papers and 7 short communications on recent developments in planting tropical and subtropical acacias presented at a workshop held in Hanoi, Vietnam, 27-30 October 1997. It brings together the research results and experiences of scientists involved in developing new technologies for acacia planting in Asia and Australia and forest managers facing practical problems growing acacias in the region. Many papers refer to well-known species, such as Acacia auriculiformis, A. mangium and A. mearnsii, but others report the results of testing lesser-known species in a range of environments. The 57 participants at the workshop reviewed the major issues arising from the meeting, identified gaps in knowledge and made recommendations for future research. The key areas were: genetic resources and tree improvement, silviculture and site management, pests and diseases, physiology (including soil symbionts), social, economic and utilisation issues, and mechanisms to foster future collaboration

Edge localized modes and the pedestal: A model based on coupled peeling-ballooning modes

A model based on magnetohydrodynamic (MHD) stability of the tokamak plasma edge region is presented, which describes characteristics of edge localized modes (ELMs) and the pedestal. The model emphasizes the dual role played by large bootstrap currents driven by the sharp pressure gradients in the pedestal region. Pedestal currents reduce the edge magnetic shear, stabilizing high toroidal mode number (n) ballooning modes, while at the same time providing drive for intermediate to low n peeling modes. The result is that coupled peeling–ballooning modes at intermediate n (3<n<20) are often the limiting instability which constrains the pedestal and triggers ELMs. These modes are characterized in shaped tokamak equilibria using an efficient new numerical code, and simplified models are developed for pedestal limits and the ELM cycle. Results are compared to several experiments, and nonideal MHD effects are briefly discussed