From a study of stopping antiprotons in a variety of elements located in a hydrogen bubble chamber, we find evidence for the existence of a neutron fringe in heavy nuclei.

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We present a measurement of the b-quark inclusive fragmentation function in Z 0 decays using a novel kinematic B-hadron energy reconstruction technique. The measurement was performed using 350,000 hadronic Z 0 events recorded in the SLD experiment at SLAC between 1997 and 1998. The small and stable SLC beam spot and the CCD-based vertex detector were used to reconstruct B-decay vertices with high efficiency and purity, and to provide precise measurements of the kinematic quantities used in this technique. We measured the B energy with good efficiency and resolution over the full kinematic range. We compared the scaled B-hadron energy distribution with models of b-quark fragmentation and with several ad hoc functional forms. A number of models and functions are excluded by the data. The average scaled energy of weakly-decaying B hadrons was measured to be < x b > = 0.709 ± 0.003 (stat) ± 0.003 (syst) ± 0.002 (model).

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We present updated results on time-dependent CP -violating asymmetries in neutral B decays to several CP eigenstates. The measurements use a data sample of about 62 million Υ (4S) → BB decays collected between 1999 and 2001 by the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. In this sample we study events in which one neutral B meson is fully reconstructed in a final state containing a charmonium meson and the flavor of the other neutral B meson is determined from its decay products. The amplitude of the CP -violating asymmetry, which in the Standard Model is proportional to sin2β, is derived from the decay time distributions in such events. We measure sin2β = 0.75 ± 0.09 (stat) ± 0.04 (syst) and |λ| = 0.92 ± 0.06 (stat) ± 0.02 (syst). The latter is consistent with the Standard Model expectation of no direct CP violation. These results are preliminary.