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We describe the status of our effort to realize a first neutrino factory and the progress made in understanding the problems associated with the collection and cooling of muons towards that end. We summarize the physics that can be done with neutrino factories as well as with intense cold beams of muons. The physics potential of muon colliders is reviewed, both as Higgs factories and compact highenergy lepton colliders. The status and time scale of our research and development effort is reviewed as well as the latest designs in cooling channels including the promise of ring coolers in achieving longitudinal and transverse cooling simultaneously. We detail the efforts being made to mount an international cooling experiment to demonstrate the ionization cooling of muons.

Secondary-electron yields were investigated for 28-MeV protons, 126-MeV oxygen-ions, and 182-MeV gold ions incident on 304 stainless-steel surfaces. The dependence on the incidence angle was studied in detail, and a system was developed which allows accurate measurements to be performed over a wide angular range extending to nearly grazing collisions. Electron yield estimates of interest for future accelerator applications are developed for 1-GeV protons, and the possible mitigation of deleterious effects by using serrated rather than flat surfaces is analyzed.

States of ' Tl, populated through the '"Pt ('Li, 4n) reaction at E = 30 to 40 MeV, were studied using in-beam yray spectroscopy techniques. An almost completely new level scheme is presented comprising the eh 9/2 vi 13/2 twoquasiparticle band which in this case is built on an I = 7 isomeric state (Ti/, = 4.8~0.2 ns) in contrast to I = 8 for all the lighter doubly odd Tl isotopes studied up to now. The systematic variation of the odd-even staggering present in these bands ofFers arguments to support the interpretation that this phenomenon is related to the signature dependence of the Coriolis interaction.NUCLEAR REACTIONS 9 Pt( Li, 4n), E = 30-40 MeV, measured Ez, I&, o. (E&. , E, 8~~-~col+.~1. deduced levels,~, 7t'~i~2 Ge (Li. ) target.

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