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Notes: Neutron diffraction has been used to measure the vortex lattice scattering for YBa2Cu3O7. A square pattern is found when the field is applied along the c axis, while a triangular pattern is found when the field is applied well away from the c axis. High-resolution measurements for the square pattern show that the vortex lattice has long-range orientational order but only short-range positional order. The temperature dependence of the penetration depth is not that expected for a superconductor with a conventional s-wave BCS-type gap. Preliminary measurements for temperatures near the irreversibility line are consistent with the occurrence of melting of the vortex lattice or glass phase.

Notes: The two major Early to Middle Palaeozoic tectonic/metamorphic events in the northern Appalachians were the Taconian (Middle to Late Ordovician) in central to western areas and the Acadian (Late Silurian to early Middle Devonian) in eastern to west-central areas. This paper presents a model for the Acadian orogenic event which separates the Acadian metamorphic realm into eastern and western belts based on distinctively different styles. We propose that the Acadian metamorphism in the east was the delayed consequence of Taconian back-arc lithospheric modification. East of the Taconian island arc, thick accumulations of Late Ordovician and Silurian sediments, coupled with plutons rising along a magmatic arc, produced crustal thermal conditions appropriate for anomalously high-T, low-P metamorphism accompanied by major crustal anatexis. In this zone, upward melt migration was coupled with subsequent E-W crustal shortening (possibly due to outboard collision with the Avalon terrane) to produce mechanical conditions that favoured formation of fold and thrust nappes and resultant tectonic thickening to the west (and probably to the east as well).The basis for the distinction between the Eastern and Western Acadian events lies in the contrasting styles of metamorphism accompanying each. Evidence for contrasting metamorphic styles consists of (1) estimated metamorphic field gradients (MFGs) based on thermobarometric studies, and (2) petrological evidence for contrasting P–T trajectories. West of the Acadian metamorphic front, the Taconian zone has an MFG in which peak temperatures of 400-600° C were reached at pressures of about 4–6 kbar, with both P and T increasing to the east. Near its western edge, the Western Acadian metamorphic overprint has a similar MFG to the Taconian, and is mainly discriminated by 40Ar/39Ar dating and microtextural evidence. East of this narrow zone, the Western Acadian overprint is characterized by progressively higher temperatures (600–725° C) and pressures (6.5–10 kbar, or more) to the east, yielding an overall MFG that lies along, or slightly above, the kyanite–sillimanite boundary on a P–T diagram. There is little or no plutonism accompanying Western Acadian metamorphism.In contrast, thermobarometry in the Eastern Acadian, east of the Bronson Hill Belt, yields high-T, intermediate-P conditions for the highest grade rocks known in New England: T= 650–750° C, P= 4.5–6.5 kbar for granulite facies assemblages which apparently formed along an ‘anticlockwise’P–T path. The Bronson Hill Belt lies geographically between the Eastern and Western Acadian zones and shows transitional petrological behaviour: anomalously high temperatures at intermediate pressures, but a ‘clockwise’ path with decompression cooling.Radiometric dating indicates peak Taconian conditions may have been achieved as early as 475 Ma in the Taconian hinterland and as late as 445 Ma in the Taconian foreland (including the Taconic allochthons). Eastern Acadian magmatism may have started as early as 425 Ma, and most nappe-stage deformation and metamorphism in the Eastern Acadian zone appears to have ended by about 410 Ma. Tectonic thickening in the Western Acadian (including the western counterparts of the nappe-stage deformation documented in the Eastern Acadian) must pre-date attainment of peak metamorphic conditions dated at 395–385 Ma. Dome-stage deformation clearly post-dates peak metamorphism and deforms metamorphic isograds. The end of Western Acadian deformation is well constrained by 370-375 Ma radiometric ages of late pegmatites and granitoids which cross-cut all structures.

Notes: Abstract In a series of experiments, no consistent effect of adult experience, i.e., exposure to the naturally occurring yeasts, Candida sonorensisand Clavispora opuntiae,on oviposition choice or short-distance attraction in inbred lines of Drosophila buzzatiiwas found. The lack of consistent effect on oviposition choice was also found in one experiment in which the flies were starved and in another experiment in which choice was determined on 2 consecutive days.

Notes: Abstract Deuteron yields from 20–350 MeV kinetic energy in antiproton annihilation at rest in12C and238U targets are compared with a coalescence model calculation. Agreement of the data with the model up to approximately 80 MeV is good. However, from 80 to 350 MeV the model increasingly underestimates the yield, by as much as on order of magnitude. These results, along with previously reported failures to explain proton spectra with first order rescattering of pions, suggest that other mechanisms are manifest in relatively rare, high energy light nucleus emission, e.g.B 〉 0 annihilations or possible six quark interactions.

Notes: Abstract Spectra of protons with momenta greater than 500 MeV/c following antiproton annihilation at rest in carbon and uranium nuclei have been measured. They are compared to recent results from other experiments and to predictions of an intranuclear cascade model. Evidence is presented for a substantialB〉0 component in the annihilation process, and an estimate of the magnitude of that component is made.

Notes: Abstract The momentum spectra of charged pions following antiproton annihilation at rest in carbon and uranium have been measured. This information complements our previous measurement of the neutral pion spectra. The total charged pion multiplicity is 2.84±0.10 and 2.47±0.09 for carbon and uranium, respectively, in good agreement with recent INC model predictions of 2.96 and 2.48 for the same quantities. However, structures predicted by the model near 200 MeV/c and 300 MeV/c related to delta-resonance production are not seen in the data. The total energy transfers to the nucleus are calculated to be 119±59 MeV(carbon) and 455±50 MeV(uranium). The possibility of exciting multifragmentation with a¯p beam impinging on heavy nuclei is discussed.

Notes: Abstract We have studied the reactions $$({{\pi ^ + } \mathord{\left/ {\vphantom {{\pi ^ + } p}} \right. \kern-\nulldelimiterspace} p})p \to ({{\pi ^ + } \mathord{\left/ {\vphantom {{\pi ^ + } p}} \right. \kern-\nulldelimiterspace} p})(K\bar K\pi )p$$ where the $$K\bar K\pi $$ system is centrally produced, at 85 GeV/c and 300 GeV/c using the CERN Omega spectrometer. A spin-parity analysis of theK S 0 K ± π ∓ system shows the presence of a strongJ PC=1++ signal which we identify as theE/f 1 (1420) meson. We also find evidence for the decayE/f 1(1420)→K S 0 K S 0 π 0 which determines theC-parity of this state to be positive. Alternative explanations of the data have been tested and ruled out. Hence we obtain the quantum numbers of theE/f 1 (1420) to beI G(JPC)=0+(1+).

Notes: Abstract The reactionpp→p f (π + π − γ)p s , where theπ + π − γ system is centrally produced, has been studied at 300 GeV/c. Theπ + π − γ mass spectrum shows evidence for aρ 0 γ decay mode of theη′ (958) andf 1 (1285). The branching ratio (f 1(1285)→ηπ + π +)/(f 1(1285)→ρ 0 γ) is found to be 5.0±0.7. No evidence is found for aρ 0(770)γ decay mode of theE/f 1 (1420) for which an upper limit BR (E/f 1(1420)→ρ 0 γ)〈0.08 at 95% CL is found.

Notes: Abstract We consider games in coalition function form on a, generally infinite, algebra of coalitions. For finite algebras the additive part mappingv →E(v ¦ ) is the usual. The concern here is the analogue for infinite algebras. The useful construction is the finitely additive stochastic process of additive parts of the game on the filtration f of finite subalgebras of . It is shown that $$\overline M $$ is an isomorphism between: a) Additive games and martingales b) Superadditive games and supermartingales c) Shapley's games of bounded deviationBD( ) in his (1953) dissertation and bounded F-processes of Armstrong (1983) d) Gilboa's spaceBS( ) (1989) and bounded processes of Armstrong (1983) Furthermore,BS( ) is shown to be the order solid hull ofBD( ) in . It is shown that the space asymp( ) of gamesv with $$\overline M $$ (v) an asymptotic martingale is the largest subspace ofBD ( ) admitting a continuous additivization of Gilboa (1989) and this is given by the assignment

Notes: Abstract The reactionpp→p f (ηπ+π−)p s where the ηπ+π− system is centrally produced has been studied at 300 GeV/c incident momentum at the CERN Ω spectrometer. The ηπ± mass spectrum shows a strong δ/a 0(980) signal having a mass of 984±4 and Γ=95±14 MeV. The ηπ+π− mass spectrum shows η′ andf 1(1285) signals over little background. A spin-parity analysis of the ηπ+π− system shows evidence for aJ PC =1++ peak at thef 1(1285) mass but no evidence for the pseudoscalar states η(1270) andl/η(1440). No evidence is found for the ηππ decay of theE/f 1(1420) meson for which we set an upper limit BR(E/f 1(1420)→ηππ)〈0.1 at 95% cl.