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The Tyrone Central Inlier is a metamorphic terrane of uncertain affinity situated outboard of the main Dalradian outcrop (south of the Fair Head–Clew Bay Line) and could represent sub-arc basement to part of the enigmatic Midland Valley Terrane. Using a combination of isotopic, structural and petrographic evidence, the tectonothermal evolution of the Tyrone Central Inlier was investigated. Sillimanite-bearing metamorphic assemblages (c. 670 °C, 6.8 kbar) and leucosomes in paragneisses are cut by granite pegmatites, which post-date two deformation fabrics. The leucosomes yield a weighted average 207Pb/206Pb zircon age of 467 ± 12 Ma whereas the main fabric yields a 40Ar–39Ar biotite cooling age of 468 ± 1.4 Ma. The pegmatites yield 457 ± 7 Ma and 458 ± 7 Ma Rb–Sr muscovite–feldspar ages and 40Ar–39Ar step-heating plateaux of 466 ± 1 Ma and 468 ± 1 Ma, respectively. The metasedimentary rocks yield Palaeoproterozoic Sm–Nd model ages and laser ablation inductively coupled plasma mass spectrometry detrital zircon U–Pb analyses from a psammitic gneiss yield age populations at 1.05–1.2, 1.5, 1.8, 2.7 and 3.1 Ga. Combined, these data permit correlation of the Tyrone Central Inlier with either the Argyll or the Southern Highland Group of the Dalradian Supergroup. The inlier was thus part of Laurentia onto which the Tyrone ophiolite was obducted.

An amplitude analysis for the reaction π+ p → π+π−π0 Δ++ at 7 GeV/c has been performed using the isobar model for the 3π system. The 3π-mass covers the range from 0.82 to 1.90 GeV. We observe strong A2 production. The spin parity of the ω ∗ (1700) is determined to be 3−. No significant A1 production can be seen.

A study of 205-GeV/c ${\ensuremath{\pi}}^{\ensuremath{-}}p$ interactions has been made with a 48 800-picture exposure in the bare Fermilab 30-inch hydrogen bubble chamber. The average number of charged particles produced per inelastic interaction is 7.99\ifmmode\pm\else\textpm\fi{}0.06. The elastic cross section is 3.18\ifmmode\pm\else\textpm\fi{}0.13 mb and the total cross section is 24.19\ifmmode\pm\else\textpm\fi{}0.44 mb. The inclusive cross sections for neutral-particle production are: $\ensuremath{\sigma}(\ensuremath{\gamma})=171.3\ifmmode\pm\else\textpm\fi{}15.3$ mb, $\ensuremath{\sigma}({K}_{S}^{0})=3.64\ifmmode\pm\else\textpm\fi{}0.61$ mb ($xl0.3$), $\ensuremath{\sigma}(\ensuremath{\Lambda})=1.71\ifmmode\pm\else\textpm\fi{}0.34$ mb ($xl0.3$), and $\ensuremath{\sigma}(\overline{\ensuremath{\Lambda}})=0.59\ifmmode\pm\else\textpm\fi{}0.23$ mb ($xl0.1$). The average number of ${\ensuremath{\pi}}^{0}'\mathrm{s}$ produced per inelastic collision is consistent with a linear rise with the number of charged particles, and about equal to the number of produced ${\ensuremath{\pi}}^{\ensuremath{-}}$ or ${\ensuremath{\pi}}^{+}$. The average number of ${K}^{0}'\mathrm{s}$, $\ensuremath{\Lambda}'\mathrm{s}$, and $\overline{\ensuremath{\Lambda}}'\mathrm{s}$ is consistent with very little dependence on the number of charged particles. General characteristics of neutral-particle production are presented and compared with other experiments. For each topology the produced neutral energy is $\ensuremath{\sim}\frac{1}{3}$ of the incident energy.

In a 48 000-picture exposure of the Fermilab 30-inch hydrogen bubble chamber to a 205 GeV/ c π − beam, we have measured 169 events of the reaction, π − p → π − π + π − p, with a cross section of 635 ± 61 μ b. This reaction proceeds almost entirely via low mass π − → 3 π and p → p ππ dissociation. Factorization is satisfied for p → pππ dissociation in πp and pp interactions.

A study of elastic scattering, one-pion production and annihilation reactions in pp interactions at 5.7 GeV/c was carried out, from the two-prong events, obtained in the hydrogen bubble chamber exposed at CERN. Single particle distributions for the reactions pp → ppπ0, pp → pnπ+ and pp → pnπ− are presented. The study of the squared momentum transfer distributions with and without charge exchange in the cross channel shows different behavior of the slope parameters versus the mass of the produced (Nπ) system. The cross sections for isobar production and for diffractive dissociation in the one-pion production reactions are obtained from a detailed Dalitz plot analysis. The results of the analysis of the decay angular distributions for the N(1510) and for the N(1680) produced in these reactions are in agreement with J = 32 and J = 52 assignment, respectively. The cross sections of the annihilation reactions pp → π+π− and pp → π+π−π0 are determined. Finally, we give some as aspects of the mass distributions for the last reaction.

The inclusive ϱ ° production cross section has been measured in the reaction π − p → π + π − X at 205 GeV/ c . We find σ ( ϱ ° ) = 13.5 ± 3.4 mb, with most of the production occuring in the central region. Assuming σ ( ϱ + ) ≈ σ ( ϱ − ) ≈ σ ( ϱ ° ), it is concluded that approximately one-third of the pions at this energy come from ϱ -decay.

Inelastic channels in ..pi../sup -/p interactions at 205 GeV/c are studied as a function of charged-particle multiplicity n/sub ch/. Experimental tests are made which are sensitive to the charge-dependent behavior of the particles, particularly at high and low rapidities. A set of new variables useful for the study of these processes is introduced. Effects which may be attributed to leading particles or leading jets are present to some extent for all n/sub ch/. Among the results presented, it is shown that at this energy there is no ''central region'' which is completely free of effects which are correlated with the charges of the incident particles. Qualitative interpretation of the results in terms of cluster-model ideas is presented; a specific simple model is calculated and compared with the data.

A new method of obtaining an experimental lower bound on the r.m.s. impact parameter of an exclusive process is applied to data on pp → ppπ+π− at 7–25 and 205 GeV/c and on π−p → π−pπ+π− at 16 and 205 GeV/c. The overall lower bounds are compared with geometrical and multiperipheral model predictions, and are shown to rule out the version of the geometrical model in which these processes become central at high energies. Our results for diffractive regions of longitudinal phase space favour a peripheral impact parameter profile for inelastic diffraction. In a related study of transverse momentum correlations in these processes, we find a predominance of “nearest-neighbour” correlations between transverse momentum transfers.

This supplement to the 1974 edition of "Review of Particle Properties," Particle Data Group [Phys. Lett. 50B, No. 1 (1974)], contains an announcement concerning the postponement of the usual Review, a list of Errata, and a tabulation of the experimental results on the newly discovered mesons.

In 205 GeV / c π − p inelastic interactions, negative particles with transverse momentum greater than 1.0 GeV / c moving forward in the center of mass outnumber similar positive particles by a factor of 3.7 to 1, greatly in excess of the corresponding ratio for small transverse momentum. The asymmetry is reversed in the backward direction. The forward asymmetry is most prominent in 2-, 4-, and 6-prong interactions, but both forward and backward asymmetries are also substantial for higher multiplicity interactions.

The continuum ambiguity is defined as a phase factor not determined by those amplitude zeros near the physical region that can be directly deduced from the data; such a factor may be approximated by a polynomial whose zeros are far from the physical region. A study of recent TIN partial wave analysis (CUTKOSKY76 and HOHLER78) reveals that such a phase is either null or negligeable; CUTKOSKY76' s amplitude is found similar to that of a partial wave analysis based on Barrelet zeros. We give general arguments based on the notion of "peripheral resonances" to explain this situation. Our arguments imply that Atkinson"s {pi}{sup +}p "continuous ambiguity" is not relevant to the reliability of Barrelet-zero amplitude analysis.

Using the available scattering and polarization pion-nucleon charge-exchange data, we have performed a Barrelet-moment analysis between 1.4 and 2.3 GeV. The method allows us to identify and discard data with important systematic error. Above 1.5 GeV, ten zeros are unambiguously required in order to represent the retained data. An attempt is made to resolve the discrete ambiguity and to obtain the location of amplitude zeros close to the physical region.

A particular case of a Mueller formula describing the absence of long-range two-particle correlations is used to predict double-pomeron cross sections from available data on single-diffraction dissociation. Although success of the formula in this application would immediately verify the double-pomeron hypothesis, the converse is not true because the formula may be invalidated by prominent low-energy resonances (such as the f 0 ) in the pomeron-pomeron total cross section. Low-statistics experiments at s = 200 and 400 GeV 2 are in order of magnitude agreement with the formula.

Author(s): Winkelmann, F.C.; Abrams, G.S.; Bingham, H.H.; Chew, D.M.; Daugeras, B.Y.; Fretter, W.B.; Friedberg, C.E.; Goldhaber, G.; Graves, W.R.; Johnson, A.D.; Kadyk, J.A.; Stutte, L.; Trilling, G.H.; Yost, G.P.; Bogert, D.; Hanft, R.; Huson, F.R.; Ljung, D.; Pascaud, C.; Pruss, S.; Smart, W.M.

A listing is presented of the 297 articles from which the data in Part I were abstracted. These listings contain additional information on each of these articles: authors, title, abstract, closely related references, beam, momenta of experiment, target, etc. One also gives tables of the data as they appeared in the original articles. Systematic comments are made specifying how the final data were obtained; for example, mass cuts for resonance production cross sections, spectator momentum cuts, corrections for systematic biases, etc. This information, extracted from the papers, is given to aid the reader in his evaluation of the results and in any comparison with other experiments.

Pion and proton diffraction dissociation are observed in π−p interactions at 205 GeV/c. The 2‐ and 4‐prong final states show evidence for N* and A1 production. Pion diffraction into masses up to ∼ 6 GeV is observed in the inclusive reaction π−p ⇒ p + X.

Pomeron- pomeron-2 pi vertices were sought in the reaction pi /sup -/p yields pi /sup -/ pi /sup +/ pi /sup -/p at 205 GeV/c. From a sample of 1 86 of these events, about 2/3 were extracted for which the rapidity ordering of the four outgoing particles makes them candidates for the double-Pomeron exchange process (i.e., the fastest and the slowest particle are respectively a pi /sup -/ and a proton). A separation from single-Pomeron processes was attempted with the help of a rapidity triangle plot. The number of possible double-Pomeron-type events was also estimated from a Regge-propagator fit to the nonhomogeneous distribution of the events within this triangle. The number of such events obtained by either method gives a cross section upper limit of 85 mu b for double-Pomeron exchange, consistent with the predictions of a pion-pole dominance model. (auth)