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1. The utiquity and many roles of exopolymers (EPS) in aquatic systems

Author: Roger S. Wotton
Subjects: eps, exopolymers, mucus, unicellular organisms, multicellular organisms, fibrils, flocs, aggregates, Aquaculture. Fisheries. Angling, SH1-691
Abstract: Exopolymers (EPS) are produced by unicellular and multicellular organisms. They consist largely of polysaccharides that hydrate rapidly on contact with water and link to form gels. EPS have many uses: in attachment; in locomotion on substrata; as a protection against predators, pathogens and changes in physico-chemical conditions; as a means of overcoming the threat of desiccation; in preventing abrasion; and in feeding. When free of organisms, some EPS form loosely associated polymer gels that are important in the development of organic matter aggregates. These aggregates, together with mucus-bound faecal pellets, play an essential role in nutrient cycling, and in the metabolism of ecosystems.;
Published: 2004
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2. Particulate and Dissolved Organic Matter as Food

Author: R. S. Wotton
Subjects: 0303 health sciences, 03 medical and health sciences, Environmental chemistry, Dissolved organic carbon, 040102 fisheries, 0401 agriculture, forestry, and fisheries, Environmental science, 04 agricultural and veterinary sciences, Particulates, 030304 developmental biology
Published: 2020
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3. Methods for Capturing Particles in Benthic Animals

Author: Roger S. Wotton
Subjects: Oceanography, Benthic zone, Environmental science
Published: 2020
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4. Measurement of the branching ratio of the decay Ξ0→Σ+μ−ν¯μ

Author: Milene Calvetti, H. Dibon, G.M. Pierazzini, L. Gatignon, G. Ruggiero, A. Gonidec, Cristina Lazzeroni, P. F. Dalpiaz, M. De Beer, S. Giudici, G. Collazuol, T. Fonseca Martin, Mauro Piccini, E. Monnier, G. Bocquet, Yu. Potrebenikov, D.J. Munday, Nicolo Cartiglia, Manfred Jeitler, M. Scarpa, G. Neuhofer, D.C. Cundy, A. Winhart, Rainer Wanke, H. Wahl, Nadia Pastrone, R. Sacco, A. Hirstius, G. Anzivino, G. Gouge, Simone Bifani, M. Behler, Marco Clemencic, M. Pepe, P. Marouelli, B. Panzer-Steindel, M. Veltri, P. Debu, E. Iacopini, R. Winston, S. Wotton, A. Maier, N. Doble, Vladimir Kekelidze, P. Cenci, E. C. Swallow, N. A. Molokanova, P. Grafström, W. Baldini, K. Eppard, Cristina Biino, M. Ziolkowski, P. Rubin, P. Lubrano, M. Holder, A. Nappi, D. T. Madigozhin, A. Peters, Evgueni Goudzovski, F. Costantini, I. Mannelli, M. Sozzi, S. Stoynev, L. Widhalm, S. Goy Lopez, Roberta Arcidiacono, U. Koch, W. Wislicki, U. Moosbrugger, M. Martini, A. Norton, M. Patel, W. Kubischta, Konrad Kleinknecht, G. Marel, M.W. Slater, A. Zinchenko, L. Masetti, Ivan Mikulec, E. Menichetti, E. Mazzucato, P. Hristov, J. R. Batley, E. Imbergamo, B. Peyaud, C. Cheshkov, V. Kozhuharov, M. Eppard, V. Falaleev, M. Savrie, F. Marchetto, A. Michetti, G.E. Kalmus, C. Cerri, B. Vallage, Fabrizio Petrucci, A. Ceccucci, Andrea Bizzeti, Leander Litov, P.L. Frabetti, A. Gianoli, Alan W. Walker, C. Morales Morales, M. Valdata, A. Dabrowski, M. C. Petrucci, Mayda Velasco, M. Markytan, M. Lenti, J.B. Cheze, G. Lamanna, Luca Fiorini, and R. Fantechi
Subjects: Physics, Nuclear and High Energy Physics, Meson, 010308 nuclear & particles physics, Branching fraction, Hadron, Analytical chemistry, Elementary particle, 01 natural sciences, Nuclear physics, 0103 physical sciences, 010306 general physics, Boson, Dimensionless quantity
Abstract: From the 2002 data taking with a neutral kaon beam extracted from the CERN-SPS, the NA48/1 experiment observed 97 Ξ 0 → Σ + μ − ν ¯ μ candidates with a background contamination of 30.8 ± 4.2 events. From this sample, the BR ( Ξ 0 → Σ + μ − ν ¯ μ ) is measured to be ( 2.17 ± 0.32 stat ± 0.17 syst ) × 10 − 6 .
Published: 2013
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5. EPS (Extracellular Polymeric Substances), silk, and chitin: vitally important exudates in aquatic ecosystems

Author: Roger S. Wotton
Subjects: Exudate, fungi, Biofilm, Particle (ecology), macromolecular substances, Aquatic Science, Biology, Mucus, Microbiology, chemistry.chemical_compound, Extracellular polymeric substance, SILK, Chitin, chemistry, medicine, Peritrophic matrix, Food science, medicine.symptom, Ecology, Evolution, Behavior and Systematics
Abstract: Exudates are ubiquitous in marine and fresh waters. They include Extracellular Polymeric Substances (EPS; including mucus, slimes, and biofilm matrices), silk, and chitin. EPS have many uses for the organisms that produce them—attachment, locomotion, feeding, and protection. They also act as glues to bind other materials, including the egesta within fecal pellets. Silk, an exudate produced only in fresh waters, is used in tube construction, to make nets used in feeding, and as a means of attachment. Chitin is the basis of the peritrophic matrix that surrounds the gut contents of some invertebrates and may act as a binding surrounding their fecal pellets. EPS are found free in the water column and in and on the substratum, as well as in close contact with the organisms that exude them. Free EPS have an essential role in particle formation and aggregation, processes that have been studied primarily in marine systems. Like EPS, silk is highly adsorptive and is found free within substrata, but rarely ...
Published: 2011
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6. Overview: the links that bind aquatic ecosystems

Author: Roger S. Wotton and Dominic T. Chaloner
Subjects: business.industry, Ecology, Aquatic ecosystem, Environmental resource management, Aquatic Science, Freshwater ecosystem, Geography, Exchange of information, Aquatic biodiversity research, Aquatic science, Ecosystem, Marine ecosystem, business, Ecology, Evolution, Behavior and Systematics
Abstract: Aquatic research historically has focused on separate aquatic ecosystems (i.e., freshwater, estuarine, and marine). We argue that this separation into subdisciplines is artificial and may even be counterproductive. Instead, scientists should consider the physical linkages between different aquatic ecosystems and the many similarities in properties and processes among those ecosystems (conceptual linkages). The 4 papers in this J-NABS BRIDGES cluster demonstrate the value of integrating information from different aquatic ecosystems. For example, the papers illustrate that transformation and transportation of nutrients and energy physically and conceptually link all aquatic ecosystems and are facilitated by the characteristics of the medium that defines them all—water. To promote the exchange of information within aquatic science, more interecosystem studies should be published in journals and books so that scientists will see parallels and linkages among freshwater, estuarine, and marine systems. O...
Published: 2011
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7. The transport of fine particulate organic matter in vegetated chalk streams

Author: Jacqueline A. Cotton, Geraldene Wharton, Luke L. Warren, Jonathon A. B. Bass, and Roger S. Wotton
Subjects: chemistry.chemical_classification, Hydrology, Ecology, Sediment, STREAMS, Aquatic Science, medicine.disease_cause, Macrophyte, Flume, Nutrient, chemistry, Aquatic plant, Pollen, medicine, Environmental science, Organic matter, Ecology, Evolution, Behavior and Systematics, Earth-Surface Processes
Abstract: Chalk streams are characterized by the presence of abundant stands of rooted macrophytes. There is typically a steep reduction in current velocity within stands and this promotes the trapping and accumulation of fine sediments. Fine sediments have also been shown to infill the gravel beds and shallow hyporheic zones of chalk streams in the process of colmation. We investigated how in-channel vegetation and colmation affect the reach-scale transport of fine particulate organic matter (FPOM, particles
Published: 2009
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8. First observation and measurement of the decay K±→π±e+e−γ

Author: Rainer Wanke, R. Fantechi, A. Ceccucci, Andrea Bizzeti, Marco Clemencic, F. Costantini, C. Cerri, I. Polenkevich, M. D. Wood, Milene Calvetti, G. Ruggiero, G.M. Pierazzini, J. Derre, I. Mannelli, A. Gonidec, B. Vallage, E. C. Swallow, P. Rubin, Roberta Arcidiacono, H. D. Wahl, M. Fidecaro, Evgueni Goudzovski, N. Doble, H. Dibon, G. Collazuol, S. Balev, M. Martini, R. Winston, B. Peyaud, L. Masetti, D. Coward, Cristina Lazzeroni, J.B. Cheze, M. Scarpa, T. Fonseca Martin, M. Holder, Mauro Raggi, B. Renk, Mauro Piccini, P. Hristov, Luca Fiorini, A.J. Culling, E. Marinova, E. Monnier, G. Neuhofer, D.J. Munday, G. Marel, A. Winhart, Nicola Cabibbo, W. Kubischta, M. Shieh, C. Cheshkov, V. Kozhuharov, D.C. Cundy, S. Stoynev, Nicolo Cartiglia, M. Pepe, Cristina Biino, Ivan Mikulec, Lau Gatignon, M. Savrie, E. Iacopini, A. A. Maier, P. F. Dalpiaz, P. Marouelli, B. Bloch-Devaux, P. Cenci, C. Handel, M. Veltri, F. Marchetto, C. Damiani, M.W. Slater, L. Widhalm, Manfred Jeitler, W. Baldini, G.E. Kalmus, V. Falaleev, A. Zinchenko, M. Ziolkowski, M. De Beer, G. Anzivino, J. R. Batley, A. Peters, S. Goy Lopez, A. Norton, M. Behler, G. Bocquet, Yu. Potrebenikov, A. Nappi, S. Wotton, Vladimir Kekelidze, S. Giudici, M. Sozzi, L. DiLella, M. Wache, Massimiliano Fiorini, D. T. Madigozhin, E. Mazzucato, C. Morales Morales, Mayda Velasco, M. Markytan, M. Lenti, A. Gianoli, Enrico Celeghini, A. Dabrowski, M. C. Petrucci, Maulik R. Patel, Konrad Kleinknecht, M. Valdata-Nappi, F. Martelli, M. Szleper, Simone Bifani, U. Moosbrugger, E. Imbergamo, A. Cotta Ramusino, G. Lamanna, Fabrizio Petrucci, Leander Litov, Alan W. Walker, P. L. Frabetti, A. Michetti, N. A. Molokanova, and K. Eppard
Subjects: Physics, Nuclear and High Energy Physics, Antiparticle, Chiral perturbation theory, Meson, 010308 nuclear & particles physics, Branching fraction, Hadron, Analytical chemistry, 01 natural sciences, Nuclear physics, Particle decay, Pion, 0103 physical sciences, 010306 general physics, Dimensionless quantity
Abstract: Using the full data set of the NA48/2 experiment, the decay K ± → π ± e + e − γ is observed for the first time, selecting 120 candidates with 7.3 ± 1.7 estimated background events. With K ± → π ± π D 0 as normalisation channel, the branching ratio is determined in a model-independent way to be Br ( K ± → π ± e + e − γ , m e e γ > 260 MeV / c 2 ) = ( 1.19 ± 0.12 stat ± 0.04 syst ) × 10 −8 . This measured value and the spectrum of the e + e − γ invariant mass allow a comparison with predictions of chiral perturbation theory.
Published: 2008
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9. Faecal pellets in streams: their binding, breakdown and utilization

Author: Paul Joyce, Roger S. Wotton, and Luke L. Warren
Subjects: chemistry.chemical_classification, biology, digestive, oral, and skin physiology, Pellets, STREAMS, Aquatic Science, biology.organism_classification, Animal science, chemistry, Gammarus, parasitic diseases, Botany, Organic matter, Simulium, Faecal pellet
Abstract: Summary 1. Faecal pellets of Gammarus (shredders) and Simulium larvae (suspension feeders) are bound by exopolymers. Immediately after egestion, Gammarus pellets are covered by a peritrophic membrane that breaks up within hours, although pellets remain intact because of internal binding materials. 2. Although they expand soon after egestion, the faecal pellets of Gammarus and Simulium remain intact for more than 30 days. Their internal structure is altered and the main agents of this change are bacteria that have survived passage through the gut (and become bound within pellets). 3. When disrupted physically, freshly egested (1- to 2-day old) Simulium faecal pellets break up into relatively large pieces whereas freshly egested Gammarus faecal pellets break apart into much smaller pieces. Disruption of 30-day old Simulium faecal pellets results in similar sized pieces to those from freshly egested pellets, but disruption of 30-day old Gammarus pellets produces pieces that are two orders of magnitude larger than those resulting from disruption of freshly egested pellets. 4. Faecal pellets of Gammarus and Simulium are eaten by stream invertebrates and are sites of microbial breakdown. Faecal pellets are a source of organic matter for benthic invertebrates, bacteria and, indirectly, for plants.
Published: 2007
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10. Impacts of suspension feeders on the modification and transport of stream seston

Author: Roger S. Wotton and Luke L. Warren
Subjects: geography, geography.geographical_feature_category, Ecology, fungi, digestive, oral, and skin physiology, Seston, Pellets, Sediment, Aquatic Science, Sink (geography), Animal science, Water column, Pellet, Environmental science, Ecology, Evolution, Behavior and Systematics, Hydrobiology, Faecal pellet
Abstract: Suspension feeders collect, and ingest, small particles and egest much larger faecal pellets into which many small particles become bound. Pellets sink through the water column and, if sinking is rapid, they become incorporated into sediments close to where they were produced. If sinking is slower, pellets are carried downstream for much longer distances. As fall velocity (the rate at which a particle settles through a quiescent water column) gives a good indication of downstream particle transport, we used laboratory experiments to investigate the effect of two factors on the fall velocity of pellets egested by blackfly larvae (Diptera: Simuliidae): their composition and their age. Larvae were fed a range of diets (organic only, organic dominated, natural, mineral dominated, and mineral only) and the fall velocity of pellets recorded for larvae of a range of sizes. Fall velocities increased with increasing mineral content, pellets generated from natural stream water during summer conditions being intermediate between the fall velocities of pellets produced by larvae feeding on the organic and mineral diets. Ageing natural pellets for 0, 10, 17, 27, 31 and 41 days resulted a progressive lowering of fall velocity for pellets of a given size. Larger pellets sank more rapidly than small pellets in all experimental treatments.
Published: 2007
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11. Do benthic biologists pay enough attention to aggregates formed in the water column of streams and rivers?

Author: Roger S. Wotton
Subjects: chemistry.chemical_classification, River ecosystem, Ecology, Pellets, Biota, STREAMS, Aquatic Science, Biology, Snow, Water column, chemistry, Benthic zone, Environmental chemistry, Organic matter, Ecology, Evolution, Behavior and Systematics
Abstract: Aggregation of organic matter occurs commonly in the water column of streams and rivers. Aggregates are formed by physicochemical or biological mechanisms, and these aggregations result in the transformation of suspended matter into much larger units. Microaggregates are formed by spontaneous assembly of organic molecules and resemble single particles. In contrast, macroaggregates (flocs and snow) are formed by binding of components with exopolymers (EPS), and they vary in size, shape, and porosity. Fecal pellets are a 3rd type of aggregate and usually are bound by EPS but are more compact than flocs or snows. Transport of aggregates to the substratum plays a significant role in the use of organic matter by microorganisms and other benthic biota, and we need to integrate these processes into our studies of lotic ecosystems. Understanding aggregation is essential to basic science, and it plays a role in planning for conservation and management at a time when flowing waters and their catchments are ...
Published: 2007
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12. Macrophytes and suspension-feeding invertebrates modify flows and fine sediments in the Frome and Piddle catchments, Dorset (UK)

Author: Jacqueline A. Cotton, Mark Trimmer, Ian A. Sanders, Geraldene Wharton, J.A.B. Bass, Catherine M. Heppell, Luke L. Warren, and Roger S. Wotton
Subjects: Hydrology, geography, geography.geographical_feature_category, biology, Drainage basin, Sediment, STREAMS, Vegetation, Ranunculus, biology.organism_classification, Macrophyte, Streamflow, Ecosystem, Geology, Water Science and Technology
Abstract: Summary This research investigated the ecosystem engineering by in-stream macrophytes, dominated by Ranunculus spp., and associated suspension-feeding blackfly larvae (Diptera: Simuliidae) for five reaches in the Frome and Piddle catchments, Dorset (UK) over one annual growth cycle (2003). This paper focuses on the modification of flow velocities and the trapping of fine sediment (particles In-stream macrophyte growth was extensive, with maximum percentage cover of 80% recorded in September and October 2003. The macrophyte cover significantly altered flow patterns and flow velocities within and between the macrophyte stands. The reduced flow velocities within the plants promoted sediment trapping, reaching volumes of 0.085 m3 of fine sediment trapped per metre square of vegetation at one site. The effective particle sizes of the sediments trapped within Ranunculus stands were dominated by the 250–500 μm fraction from March to July 2003 whereas a higher proportion of smaller fractions occurred from October to December. Faecal pellets were highly abundant in the sediments trapped within Ranunculus stands (up to 2.2 × 108 faecal pellets per m2) and their dimensions (total size range 25–400 μm) fall within the dominant size fraction of the trapped sediments. Our findings demonstrate the need to consider the biogenic component of the fine sediments in chalk streams in future studies of sediment and nutrient dynamics.
Published: 2006
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13. The effects of seasonal changes to in-stream vegetation cover on patterns of flow and accumulation of sediment

Author: Roger S. Wotton, Jacqueline A. Cotton, J.A.B. Bass, Geraldene Wharton, and Catherine M. Heppell
Subjects: Hydrology, Alluvion, biology, Growing season, Sediment, Alluvium, Vegetation, Silt, Ranunculus, biology.organism_classification, Geology, Earth-Surface Processes, Macrophyte
Abstract: In-stream macrophytes are typically abundant in nutrient-rich chalk streams during the spring and summer months and modify the in-stream environment by altering river flows and trapping sediments. We present results from an inter-disciplinary study of two river reaches in the River Frome catchment, Dorset (UK). The investigation focused on how Ranunculus (water crowfoot), the dominant submerged macrophyte in the study reaches, modified patterns of flow and sediment deposition. Measurements were taken on a monthly basis throughout 2003 to determine seasonal patterns in macrophyte cover, associated changes in the distributions of flow velocities and the character and amount of accumulated fine sediment within stands of Ranunculus. Maximum in-stream cover of macrophytes exceeded 70% at both sites. Flow velocities were less than 0.1 m s− 1 within the stands of Ranunculus and accelerated to 0.8 m s− 1 outside the stands. During the early stages of the growth of Ranunculus, fine sediment mostly accumulated within the upstream section of the plant but the area of fine sediment accumulation extended into the downstream trailing section of the plant later in the growing season. The fine sediment accumulations were dominated by sand (63–1000 μm) with silts and clays (0.37–63 μm) comprising
Published: 2006
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14. Matanza de animales por motivos sanitarios

Author: J.W. Galvin, M.C. Chimbombi, Harry J. Blokhuis, D. de Jong, and S. Wotton
Subjects: Veterinary medicine, medicine.medical_specialty, business.industry, Outbreak, General Medicine, Disease, Disease control, RESPIRATORY MOVEMENTS, Medicine, Animal Science and Zoology, Flock, business, Intensive care medicine, Disease transmission
Abstract: In emergency disease outbreaks, large numbers of animals may need to be killed for control, containment and/or eradication purposes. Strategies for disease control will usually involve complete depopulation of herds/flocks, and may extend to depopulation across designated areas. Live animals present the major risk of spreading infectious agents so their slaughter should be completed as quickly as possible, with minimal pain and distress to the animals. The method chosen for killing of animals must be humane, efficient and safe for people and the environment. The tasks should be conducted under the supervision of an official veterinarian, supported by a sufficient number of adequately trained and competent personnel. It is essential to ensure all animals are dead, as demonstrated by the cessation of cardiac and respiratory movements. This paper discusses methods by which animals may be killed for disease control purposes.
Published: 2005
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15. Ubicuidad y funciones diversas de los exopolímeros (EPS) en los sistemas acuáticos

Author: Roger S. Wotton
Subjects: fibrils, Nutrient cycle, multicellular organisms, SH1-691, Aquatic Science, Biology, Oceanography, flocs, lcsh:Aquaculture. Fisheries. Angling, exopolymers, mucus, Aquaculture. Fisheries. Angling, Ecosystem, Organic matter, organismos pluricelulares, chemistry.chemical_classification, lcsh:SH1-691, Ecology, unicellular organisms, Aquatic ecosystem, organismos unicelulares, copos, exopolímeros, Multicellular organism, chemistry, aggregates, %22">Fish , fibrilas, EPS, Desiccation, agregados, Faecal pellet
Abstract: Exopolymers (EPS) are produced by unicellular and multicellular organisms. They consist largely of polysaccharides that hydrate rapidly on contact with water and link to form gels. EPS have many uses: in attachment; in locomotion on substrata; as a protection against predators, pathogens and changes in physico-chemical conditions; as a means of overcoming the threat of desiccation; in preventing abrasion; and in feeding. When free of organisms, some EPS form loosely associated polymer gels that are important in the development of organic matter aggregates. These aggregates, together with mucus-bound faecal pellets, play an essential role in nutrient cycling, and in the metabolism of ecosystems.; Los exopolímeros (EPS) son producidos por organismos unicelulares y pluricelulares. Están constituidos fundamentalmente por polisacáridos que se hidratan rápidamente en contacto con el agua y se unen para formar geles. Los EPS tienen muchos usos; en la fijación; en la locomoción sobre sustratos; como protección contra los depredadores, los patógenos y los cambios en la condiciones fisicoquímicas; como una manera de contrarrestar el peligro de la desecación; para evitar la abrasión, y en la alimentación. Cuando se hallan libres de organismos, algunos EPS forman geles de polímeros asociados de manera laxa que son importantes para el desarrollo de agregados de materia orgánica. Estos agregados, junto con los paquetes fecales cohesionados con mucus, desempeñan un papel esencial en el ciclado de los nutrientes y en el metabolismo de los ecosistemas.
Published: 2004
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16. Black flies in the boreal biome, key organisms in both terrestrial and aquatic environments: A review

Author: Björn Malmqvist, Kalevi Kuusela, Peter H. Adler, Richard W. Merritt, and Roger S. Wotton
Subjects: 0106 biological sciences, Ecology, biology, Aquatic ecosystem, Biome, biology.organism_classification, 010603 evolutionary biology, 01 natural sciences, 010602 entomology, Boreal, Bacillus thuringiensis, Key (lock), Ecology, Evolution, Behavior and Systematics
Abstract: Black flies in the boreal biome, key organisms in both terrestrial and aquatic environments: A review
Published: 2004
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17. Cohort study in South and West England of the influence of specialization on the management and outcome of patients with oesophageal and gastric cancers

Author: Tim J Peters, Ian Harvey, Deborah Edwards, C. Bedford, S. Wotton, Max O Bachmann, and D. Alderson
Subjects: medicine.medical_specialty, Esophageal Neoplasms, Workload, Cancer Care Facilities, Cohort Studies, Stomach Neoplasms, Internal medicine, medicine, Humans, Hospital Mortality, Practice Patterns, Physicians', Survival analysis, Esophageal disease, business.industry, Hazard ratio, Cancer, Odds ratio, Esophageal cancer, medicine.disease, Survival Analysis, Hospitals, Confidence interval, Surgery, Treatment Outcome, England, Regression Analysis, business, Follow-Up Studies, Cohort study
Abstract: Background To evaluate specialization in National Health Service (NHS) cancer care, volume–outcome relationships were examined. Methods This was a cohort study of 1512 patients with oesophageal or gastric cancer in 23 acute NHS hospitals. Outcomes were survival time and operative (30 day) mortality. Multiple regression analysis was performed, adjusted for diagnoses, prognoses and treatments. Results For oesophageal cancer, the operative mortality rate decreased by 40 per cent (odds ratio 0·60 (95 per cent confidence interval (c.i.) 0·36 to 0·99 per cent); P = 0·047) for each increase of ten patients in doctors' annual surgical caseloads, and the risk of death decreased by 8 per cent (hazard ratio 0·92 (95 per cent c.i. 0·85 to 0·99); P = 0·021) for each increase of ten patients in doctors' annual caseloads. For gastric cancer, the operative mortality rate decreased by 41 per cent (odds ratio 0·59 (95 per cent c.i. 0·32 to 1·07)) for each increase of ten patients in doctors' annual surgical caseloads, and the risk of death decreased by 7 per cent (hazard ratio 0·93 (95 per cent c.i. 0·89 to 0·98); P = 0·009) for each increase of ten patients in hospitals' annual caseloads. Patients of higher-volume doctors were more likely to receive most investigations and treatments, independently of presenting features. Conclusion The study supports concentration of services for oesophageal and gastric cancers. Specialization of doctors and their teams is at least as important as specialization of hospitals.
Published: 2002
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18. [Untitled]

Author: Roger S. Wotton
Subjects: Total organic carbon, Ecology, Sediment–water interface, Rapid sand filter, Environmental engineering, Sand filter, Environmental science, Portable water purification, Aquatic Science, Water pollution, Slow sand filter, Filter (aquarium)
Abstract: Slow sand filters are used to purify drinking water. Each filter consists of a large tank containing a bed of sand through which water passes at typical rates of 0.1–0.3 m h−1. Water is cleaned by physico–chemical and biological processes occurring at the air–water interface, within the bulk water, over the surface of the sand, and within the bed of sand. The processes found in sand filters replicate many of those found in natural sand banks and sandy beaches.
Published: 2002
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19. Suspension feeders transform massive amounts of seston in large northern rivers

Author: Yixin Zhang, Björn Malmqvist, and Roger S. Wotton
Subjects: chemistry.chemical_classification, Hydrology, geography, animal structures, geography.geographical_feature_category, biology, Ecology, Seston, chemistry.chemical_element, Sedimentation, biology.organism_classification, Habitat destruction, chemistry, Dry weight, Tributary, Environmental science, Organic matter, Corbicula fluminea, Carbon, Ecology, Evolution, Behavior and Systematics
Abstract: The concentration and transport of faecal pellets (FPs) produced by blackfly (Diptera: Simuliidae) larvae were estimated in a large, free-flowing river in the north of Sweden during 1997-1999. FPs were abundant from May through August and FP loads in transport peaked at 429 t dry mass d(-1) at a site in the lower part of the river in 1997. Daily transport at the same site, averaged over each study period (16 Jun.-18 Sep. 1997, 6 Apr.-10 Sep. 1998, and 21 Apr.-5 Aug. 1999). was estimated to be 93.7 t dry mass (3.7 t carbon), 47.5 t dry mass (1.9 t carbon and) and 69.2 t dry mass (2.7 t carbon), respectively. On a large scale, there was a downstream trend of increasing FP concentration and, during periods with greater discharge, sedimentation was reduced so that more material was exported from the river. Samples from six sites in a regulated river (into which our focal river flows) parallel to six sites in the unregulated tributary showed considerably lower FP concentrations in the regulated river, presumably because of much smaller blackfly populations as a consequence of habitat loss through damming. A survey of two other large, unregulated rivers in northern Sweden confirmed that these also carry large amounts of FPs. We conclude that the transformation of small suspended food particles into considerably larger FPs by huge populations of filter-feeding blackfly larvae is a major process in large northern rivers.
Published: 2001
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20. Sorption of pesticides to novel materials: snail pedal mucus and blackfly silk

Author: R. S. Wotton, W.A. House, C. Brereton, and Patrick D. Armitage
Subjects: chemistry.chemical_classification, Health, Toxicology and Mutagenesis, Sorption, Simazine, General Medicine, Pesticide, Toxicology, Pollution, Fenitrothion, chemistry.chemical_compound, Parathion, chemistry, Environmental chemistry, Malathion, Organic matter, Atrazine
Abstract: The distribution coefficients for 10 pesticides (atrazine, cyanazine, desmetryn, fenitrothion, malathion, parathion, prometryn, propazine, simazine, terbutryn) to both snail pedal mucus and blackfly larval silk are measured and found to be orders of magnitude higher than for soil organic carbon. The lowest values are found for the triazine herbicides (e.g. 19,000 ml g −1 for simazine on silk) and the highest for the organophosphorus insecticides (e.g. 242,000 ml g −1 for malathion). The distribution coefficients for pedal mucus are more difficult to quantify in terms of the organic carbon distribution coefficients but, by mass, are much higher than the corresponding soil distribution coefficients. The sorption affinities obtained for blackfly silk are similar in magnitude to literature data for sorption of pesticides and polyaromatic hydrocarbons to natural organic colloids.
Published: 1999
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21. Midge larvae (Diptera: Chironomidae) as engineers in slow sand filter beds

Author: Roger S. Wotton and Kimio Hirabayashi
Subjects: Larva, animal structures, Environmental Engineering, biology, Ecology, Ecological Modeling, digestive, oral, and skin physiology, fungi, Sand filter, Pellets, biology.organism_classification, Schmutzdecke, Pollution, Chironomidae, Slow sand filter, law.invention, Agronomy, law, parasitic diseases, Midge, Waste Management and Disposal, Filtration, Water Science and Technology, Civil and Structural Engineering
Abstract: Midge larvae (Diptera: Chironomidae) are found abundantly (7.4×10 4 larvae m −2 ) in slow sand filter beds open to the atmosphere. Larvae eat the schmutzdecke accumulated at the sand surface and egest faecal pellets that are compacted and bound with mucopolysaccharides, faecal pellet size increasing with larval size. Pellets become diffuse after conditioning by microorganisms, and pellets, whether fresh or conditioned, are broken by abrasion. As up to 23% of the sand surface can be covered by fresh faecal pellets each day, midge larvae probably play an important role in the functioning of slow sand filters.
Published: 1999
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22. Fecal pellets from a dense aggregation of suspension-feeders in a stream: An example of ecosystem engineering

Author: Timo Muotka, Kristina Larsson, Björn Malmqvist, and Roger S. Wotton
Subjects: chemistry.chemical_classification, Hydrology, Pellets, Biomass, Aquatic Science, Biology, Oceanography, Population density, Ecosystem engineer, Suspension (chemistry), chemistry, Benthic zone, Environmental chemistry, Organic matter, Ecosystem
Abstract: Blackfly larvae (Diptera: Simuliidae) are "allogenic ecosystem engineers" that capture fine particulate and dissolved matter from suspension and egest much larger fecal pellets. We investigated the effects of blackfly larvae on organic matter transport at 25 sites along a small stream that flowed 500 m from a lake to the sea. Blackfly density was high upstream (>6 x 10(5) ind. m(-2)) and the numbers of fecal pellets in suspension rose markedly downstream from the blackfly aggregation. A total of 1.6 x 10(9) fecal pellets (biomass 3.2 kg C d(-1)) were discharged to the sea each day and 8.0 x 10(8) pellets (biomass 1.6 kg C d(-1)) were lost from suspension. Sedimenting pellets were available to the benthic microbial and invertebrate communities.
Published: 1998
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23. Have we underestimated the role of faeces in aquatic systems?

Author: Roger S. Wotton
Subjects: Total organic carbon, Ecology, Aquatic ecosystem, Environmental chemistry, Ecosystem, Biology
Published: 2006
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24. A transputer network for data acquisition in a multichannel FADC system

Author: M. Feuerstack, S. Wotton, A. Dieckmann, H. Ihssen, and H. von der Schmitt
Subjects: Physics, Nuclear and High Energy Physics, Large Hadron Collider, business.industry, Transputer, Controller (computing), Detector, USable, Upgrade, Data acquisition, Electronics, business, Instrumentation, Computer hardware
Abstract: Large multichannel Flash-ADC systems pose the problem of reducing and collecting data from many thousands of channels, residing in several crates. Custom systems like the DL300 Flash-ADC system used at the OPAL experiment at LEP, CERN, are usually more cost effective in large systems than assemblages based on standard busses, but need specific solutions to integrate them into the computing environment. Transputer links represent a powerful, yet easily usable medium for transporting data. The upgrade of the OPAL central jet chamber read-out system consists of a new crate controller with one transputer per Flash-ADC crate. The resulting transputer network handles trigger distribution, data reduction and data transportation tasks. In future experiments, transputer networks may present an option to transport data from electronics, which is tightly integrated into the detector.
Published: 1997
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25. Growth of Anopheles mosquito larvae on dietary microbiota in aquatic surface microlayers

Author: Dominic T. Chaloner, C. A. Yardley, Roger S. Wotton, and Richard W. Merritt
Subjects: Anopheles gambiae, Microorganism, Zoology, Bacterial growth, Microbiology, Anopheles, parasitic diseases, Dissolved organic carbon, Animals, Organic matter, Amino Acids, Ecology, Evolution, Behavior and Systematics, chemistry.chemical_classification, Larva, General Veterinary, biology, fungi, biology.organism_classification, Animal Feed, Mosquito control, Glucose, chemistry, Insect Science, Parasitology, Gentamicins
Abstract: Hydrophobic organic matter accumulates under the surface film of water bodies to form the surface microlayers. Heterotrophic microorganisms use this organic matter for growth, and they, in turn, are fed upon by Anopheles mosquito larvae and other animals. From laboratory experiments we show that two species of mosquito larvae, Anopheles gambiae and An.quadrimaculatus, grew most rapidly where surface microlayers were present and, especially, where labile dissolved organic matter was added to promote growth of microorganisms. The importance of microorganisms was confirmed by the addition of gentamicin antibiotic, which suppressed the microbiota and reduced the growth of larvae feeding on surface microlayers. Anopheles larvae grew well on a suspension of finely ground fish food to which the antibiotic had been added, showing that reduced growth was not due to gentamicin itself. Because sub-surface microorganisms are the components of the larval diet that most affect growth, we discuss their relevance to strategies for larval control of Anopheles mosquitoes.
Published: 1997
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26. The role of faecal pellets in lowland permeable rivers

Author: Roger S. Wotton, Geraldene Wharton, and Luke L. Warren
Subjects: chemistry.chemical_classification, chemistry, Ecology, Organic matter, Biology, Faecal pellet
Published: 2005
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27. Substratum preferences by larvae of three species of midge (Diptera: Chironomidae)

Author: Roger S. Wotton and Dominic T. Chaloner
Subjects: chemistry.chemical_classification, Larva, biology, Ecology, Particle (ecology), Aquatic Science, biology.organism_classification, Chironomidae, Slow sand filter, chemistry, Botany, Midge, Organic matter, Cladophora, Tanytarsus
Abstract: Three chironomid midge (Diptera: Chironomidae) species (Cricotopus sylvestris (Fabricius); Psectrocladius limbatellus (Holmgren), Tanytarsus fimbriatus Reiss and Fittkau) live at high densities and dominate the midge assemblage found in slow sand filter beds. After filter beds are drained and cleaned, the substratum consists of sand of different particle sizes, but once beds are refilled and in operation, organic material accumulates on the sand and Cladophora grows. In laboratory experiments, we found that larvae of the three midge species preferred different substratum types: C. sylvestris preferred sand to both Cladophora and organic material, P. limbatellus preferred Cladophora, and Tanytarsus sp. preferred organic material. Some evidence of preference for one particle size was also found, but compared with substratum types, this was neither as marked or contrasting between the three species. The contrasting preferences that we found in the laboratory suggest that the substratum will influence the microdistribution of the three species in filter beds, and provide further evidence of the importance of substratum in midge assemblages.
Published: 1996
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28. Tube Building by Larvae of 3 Species of Midge (Diptera:Chironomidae)

Author: Dominic T. Chaloner and Roger S. Wotton
Subjects: Larva, biology, Ecology, Aquatic ecosystem, media_common.quotation_subject, Aquatic Science, biology.organism_classification, Chironomidae, Competition (biology), Midge, Ecosystem, Tube (container), Tanytarsus, Ecology, Evolution, Behavior and Systematics, media_common
Abstract: Tube building is an important and characteristic behaviour of larvae of many chironomid midges (Diptera:Chironomidae). In laboratory experiments, differences were found in the tube building of larvae of 3 midge species (Cricotopus sylvestris (Fabricius), Psectrocladius limbatellus (Holmgren), and Tanytarsus sp.). Tanytarsus sp. built a single, robust tube close to those of conspecifics; P. limbatellus built a few, less robust tubes, which were evenly spaced; and C. sylvestris built many more, shorter tubes. Cricotopus sylvestris also used less of the substratum within feeding territories for tube building, and was more likely to abandon tubes than the other species. These contrasts in tube building illustrate the diversity of this behaviour, which is likely to be an important feature of ecosystem engineering within aquatic systems where midges are found.
Published: 1996
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29. Search for chargino and neutralino production using the OPAL detector at =130−136 GeV at LEP

Author: Tara Shears, W. J. McDonald, B. C. Shen, P. A. Hart, A. P. Wagner, Reda Tafirout, D. Chrisman, Volker Blobel, M. J. Pearce, Sachio Komamiya, Ekg Sarkisyan, Siegfried Bethke, B. Nijjhar, W. G. Scott, S. L. Chu, T. Behnke, J. Steuerer, M. Gruwé, C. M. Hawkes, Richard Nisius, P. Weber, Marco Cuffiani, Stephen Lloyd, G. G. Hanson, E. Ros, A. T. Watson, S. B. Anderson, P. Szymanski, Daniel Lellouch, T. J. Smith, K. Stephens, P. W. Jeffreys, E. Lefebvre, Andris Skuja, Koji Yoshimura, Takehiko Mori, S. Yamashita, W. R. Gibson, Madjid Boutemeur, F. Odorici, G. Giacomelli, Dezso Horvath, M. J. Losty, D. M. Strom, S. Petzold, G. D. Long, A. Joly, P. Poffenberger, P. Igo-Kemenes, Shlomo Dado, Matthias Schröder, T. P. Kokott, Stan Bentvelsen, Jean-Arcady Meyer, B. T. Bouwens, P. Schenk, M. Hauschild, A. Luig, Tetsuro Mashimo, H. Fukui, V. Zacek, F. S. Merritt, Ehud Duchovni, V. Gibson, P. G. Estabrooks, H. Jeremie, R. E. Hughes-Jones, R. K. Keeler, R. Rylko, R. M. Brown, Lorne Levinson, M. S. Dixit, M. Jimack, Frans Meijers, D. L. Rees, M. Hapke, M. Thiergen, H. Lafoux, D. E. Hutchcroft, Achim Stahl, F. Palmonari, Gilles Beaudoin, C. Sbarra, A. Skillman, F. Scharf, C. Markus, N. I. Geddes, German Martinez, J. J. Ward, W. Gorn, Michael Hildreth, P. Vikas, R. D. Heuer, P. M. Watkins, Giora Mikenberg, P. Schütz, E. do Couto e Silva, S. W. Gensler, Fabrizio Fabbri, S. Söldner-Rembol, A. S. Turcot, R. W. Springer, D. Lanske, A. D. Schaile, C. Hartmann, D. E. Plane, T. Kobayashi, J. Bechtluft, N. L. Rodning, B. Schmitt, Sven Menke, G. T. Jones, M. J. Oreglia, D. R. Ward, B. Stockhausen, Paul Kyberd, F. K. Loebinger, T. Kress, R. Lahmann, D. C. Imrie, M. Palazzo, J. A. McKenna, M. R. Ingram, E. H. Vokurka, James Pinfold, Stephen Hillier, Silvia Arcelli, G. M. Dallavalle, W. Matthews, B. Poli, S. Braibant, G. Yekutieli, D. R. Rust, Stefan Kluth, D. M. Gingrich, M. A. Thomson, E. Tsur, D. G. Fong, C. Lewis, Joleen Pater, C. Darling, Gabriella Pasztor, H. Mes, I. P. Duerdoth, Shlomit Tarem, J. Gascon, Paolo Giacomelli, M. Verzocchi, K. W. Bell, M. Hansroul, C. Y. Chang, E. K. U. Gross, R. Giacomelli, T. Hilse, R. Bartoldus, G. P. Siroli, J. King, P. Fath, O. Runolfsson, A. Gaidot, P. Mättig, J. Pálinkás, Shoji Asai, J. C. Hill, Gregor Herten, T. Wlodek, M. Sproston, S. M. Gascon-Shotkin, Christoph Geich-Gimbel, A. A. Carter, G. A. Snow, C. P. Ward, A. M. Lee, P. Taras, A. Rooke, Misao Sasaki, A. Malik, Carsten Daniel Burgard, J. G. Layter, Michael Kobel, M. Tecchio, A. H. Bain, I. J. Bloodworth, E. von Törne, J. W. Gary, Ron Folman, C. Beeston, E. A. Mckigney, W. P. Lai, R. Kowalewski, B. Wilkens, U. Müller, D. S. Koetke, C. Charlesworth, N. Tesch, J. R. Carter, G. N. Patrick, Otmar Biebel, Claudio Grandi, John Allison, Hans-Christian Schultz-Coulon, Randall Sobie, Michael Schulz, G. D. Lafferty, Marcello Mannelli, Matthew Evans, Gunter Wolf, J. E. Pilcher, Julie Kirk, Stefania Xella, C. H. Shepherd-Themistocleous, A. M. Rossi, R. J. Homer, F. X. Gentit, A. J. Martin, R. Howard, Yoram Rozen, A. Fürtjes, M. F. Turner-Watson, N. K. Watson, K. Ametewee, M. Morii, Peter R Hobson, J. E. Conboy, J. S. White, Roger Jones, S. Wotton, J. P. Pansart, H. M. Fischer, J. M. Roney, P. Scharff-Hansen, P. E.L. Clarke, P. Utzat, M. K. Jones, Gideon Alexander, M. Foucher, A. Michelini, Paolo Capiluppi, R. G. Kellogg, J. P. Martin, R. Van Kooten, M. Tscheulin, P. Routenburg, A. I. McNab, S. De Jong, M. G. Rison, Guenter Duckeck, Frank Fiedler, J. Letts, G. W. Wilson, Junichi Kanzaki, S. A. Robins, D. Karlen, J. Goldberg, W. Mohr, O. Schaile, A. Posthaus, P. S. Wells, B. Nellen, M. Fierro, S. W. O'Neale, Norbert Wermes, Sherry Towers, T. Kawamoto, H. Przysiezniak, K. J. Anderson, T. J. McMahon, J. E.G. Edwards, A. M. Smith, Terry Richard Wyatt, C. K. Hargrove, M. Starks, J. E. Bloomer, A. N. Bell, F. Wäckerle, G. Vasseur, B. Lorazo, H. G. Evans, M. J. Goodrick, I. Cohen, S. Orito, J. Schwiening, M. Rosvick, R. K. Carnegie, P. Berlich, J. A. Wilson, O. C. Cooke, J. von Krogh, Csaba Hajdu, R. J. Hawkings, Stefano Marcellini, L. A. del Pozo, Gideon Bella, H. J. Burckhart, Jacqueline Batley, G. Azuelos, T. Omori, H. O. Ogren, D. Rigby, R. J. Hemingway, D. Axen, A. Jawahery, T. Geralis, B. W. Kennedy, P. Jovanovic, Peter Sherwood, Peter Krieger, Manuella Vincter, Alessandro Montanari, J. Ludwig, K. Runge, P. Bock, Dave Charlton, C. Dallapiccola, R. Bürgin, P. Gagnon, N. Altekamp, R. J. Barlow, D. J. Miller, A. K. Honma, U. Jost, R. Mir, A. Sittler, H. Takeda, F. G. Oakham, E. L. Barberio, H. M. Bosch, J. Lauber, and F. Strumia
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Electron–positron annihilation, High Energy Physics::Phenomenology, Detector, Scalar (mathematics), Lightest Supersymmetric Particle, Lower limit, Nuclear physics, Chargino, Neutralino, High Energy Physics::Experiment, Particle Physics - Experiment, Minimal Supersymmetric Standard Model
Abstract: A search for charginos and neutralinos, predicted by supersymmetric theories, has been performed using a data sample of 2.6 pb−1 at a centre-of-mass energy of S=130 GeV and 2.6 pb−1 at 136 GeV collected with the OPAL detector at LEP during November 1995. No candidate events were observed. The 95% C.L. lower limit on the lightest chargino mass in the Minimal Supersymmetric Standard Model is 65.4 GeV if the universal scalar mass m0 is greater than 1 TeV, and 58.7 GeV for the smallest m0 compatible with slepton and sneutrino mass limits obtained at centre-of-mass energies near the Z peak. These limits were obtained under the conditions that the lightest chargino is heavier than the lightest neutralino by more than 10 GeV and tan β is larger than 1.5. The results of a model independent search for charginos and neutralinos are also given.
Published: 1996
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30. Topological search for the production of neutralinos and scalar particles

Author: C. Sbarra, G. Yekutieli, Ehud Duchovni, J. Lauber, Shlomo Dado, A. S. Turcot, Dave Charlton, A. A. Carter, Ron Folman, M. Jimack, Roger Jones, P. E.L. Clarke, M. K. Jones, Otmar Biebel, P. Utzat, Reda Tafirout, S. W. Gensler, T. Kobayashi, J. P. Martin, M. Kobe, M. Tscheulin, Matthias Schröder, Giora Mikenberg, M. Thiergen, F. Strumia, M. G. Rison, R. Bürgin, Andris Skuja, S. Petzold, G. D. Long, Frank Fiedler, P. S. Wells, Terry Richard Wyatt, J. E. Bloomer, H. Mes, I. P. Duerdoth, P. Fath, H. M. Fischer, A. Michelini, O. Schaile, M. Starks, Sachio Komamiya, Theodoros Geralis, E. Ros, R. Kowalewski, B. Stockhausen, Paul Kyberd, S. A. Robins, E. Lefebvre, F. Odorici, T. P. Kokott, K. Ametewee, F. K. Loebinger, S. De Jong, Tara Shears, Gideon Alexander, A. Luig, H. Przysiezniak, R. W. Springer, Tetsuro Mashimo, K. Stephens, Paolo Capiluppi, Gregor Herten, D. J. Miller, J. Steuerer, A. I. McNab, J. Goldberg, B. Nellen, R. Bartoldus, B. Wilkens, I. J. Bloodworth, J. Letts, P. A. Hart, R. Lahmann, D. C. Imrie, M. Palazzo, H. O. Ogren, S. Braibant, Gabriella Pasztor, Norbert Wermes, T. Behnke, A. N. Bell, S. Yamashita, J. P. Pansart, Joleen Pater, W. R. Gibson, Richard Keeler, M. J. Pearce, Mathieu Doucet, Georges Azuelos, Sherry Towers, V. Gibson, J. E. Pilcher, Christoph Geich-Gimbel, T. J. McMahon, P. Igo-Kemenes, E. Tsur, S. M. Gascon-Shotkin, G. P. Siroli, J. King, R. D. Heuer, Fabrizio Fabbri, T. Kawamoto, B. T. Bouwens, M. Verzocchi, D. Axen, A. Jawahery, G. A. Snow, C. P. Ward, G. W. Wilson, K. W. Bell, J. Pálinkás, H. Jeremie, M. Hauschild, H. G. Evans, J. Schwiening, R. K. Carnegie, M. J. Goodrick, I. Cohen, M. Gruwé, J. C. Hill, Misao Sasaki, S. Söldner-Rembold, Peter Sherwood, M. Fierro, J. E.G. Edwards, C. Markus, C. M. Hawkes, R. E. Hughes-Jones, D. Chrisman, Volker Blobel, R. Giacomelli, Yoram Rozen, D. R. Rust, J. A. Wilson, W. J. McDonald, B. C. Shen, Siegfried Bethke, A. K. Honma, W. Gorn, G. T. Jones, Alexander Wagner, Ekg Sarkisyan, Lorne Levinson, P. W. Jeffreys, Matthew Evans, E. H. Vokurka, S. Orito, M. Rosvick, M. F. Turner-Watson, Achim Stahl, J. Ludwig, A. Rooke, D. R. Ward, H. Lafoux, A. M. Rossi, T. Kress, B. Nijjhar, W. G. Scott, J. G. Layter, M. Morii, Peter R Hobson, K. Runge, P. Bock, A. J. Martin, Gilles Beaudoin, Richard Nisius, R. Howard, M. Foucher, A. Skillman, A. M. Lee, P. Routenburg, P. Weber, Marco Cuffiani, Stephen Lloyd, M. Tecchio, E. von Törne, Robert M Brown, Gideon Bella, C. H. Shepherd-Themistocleous, H. J. Burckhart, S. Asa, J. S. White, S. W. O'Neale, C. Charlesworth, M. R. Ingram, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, E. do Couto e Silva, P. Scharff-Hansen, P. Gagnon, Stefan Kluth, Shlomit Tarem, P. Bright-Thomas, K. J. Anderson, N. I. Geddes, Michael Hildreth, M. Hapke, D. E. Plane, S. L. Chu, Jacqueline Batley, B. Schmitt, O. C. Cooke, R. Van Kooten, Stephen Hillier, U. Müller, N. L. Rodning, B. Poli, C. K. Hargrove, D. Rigby, R. J. Hemingway, Stefania Xella, D. E. Hutchcroft, Junichi Kanzaki, G. M. Dallavalle, J. E. Conboy, J. J. Ward, P. Vikas, A. Fürtjes, P. Poffenberger, A. M. Smith, Sven Menke, A. Sittler, G. Vasseur, B. Lorazo, F. Wäckerle, D. Karlen, C. Burgard, T. Omori, D. M. Gingrich, Alan Watson, J. von Krogh, D. Lanske, B. W. Kennedy, P. Jovanovic, Silvia Arcelli, P. Schütz, M. J. Oreglia, P. Berlich, R. J. Hawkings, A. Gaidot, Gunter Wolf, F. X. Gentit, H. M. Bosch, G. G. Hanson, L. A. del Pozo, Austin Ball, Peter Krieger, James Pinfold, C. Y. Chang, D. G. Fong, C. Lewis, J. Gascon, D. M. Strom, C. Darling, P. Taras, T. J. Smith, Manuella Vincter, Alessandro Montanari, Paolo Giacomelli, M. Hansroul, A. Malik, G. Giacomelli, E. A. Mckigney, J. W. Gary, P. Mättig, D. S. Koetke, S. Wotton, Marcello Mannelli, R. J. Homer, J. R. Carter, G. N. Patrick, Julie Kirk, U. Jost, R. Mir, H. Fukui, P. Schenk, R. Rylko, Daniel Lellouch, T. Hilse, S. B. Anderson, C. Hartmann, Takehiko Mori, P. Szymanski, F. S. Merritt, O. Runolfsson, W. P. Lai, V. Zacek, H. Takeda, M. S. Dixit, Frans Meijers, F. G. Oakham, E. L. Barberio, C. Dallapiccola, C. Beeston, A. Joly, N. Altekamp, Stan Bentvelsen, R. J. Barlow, J. Bechtluft, J. A. McKenna, Claudio Grandi, Hans-Christian Schultz-Coulon, Randall Sobie, Michael Schulz, G. D. Lafferty, Guenter Duckeck, J. M. Roney, John Allison, Madjid Boutemeur, R. G. Kellogg, Csaba Hajdu, Stefano Marcellini, P. G. Estabrooks, P. M. Watkins, Koji Yoshimura, D. L. Rees, F. Scharf, German Martinez, A. D. Schaile, N. K. Watson, W. Mohr, A. Posthaus, W. Matthews, M. A. Thomson, E. K. U. Gross, T. Wlodek, M. Sproston, and N. Tesch
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Missing energy, Electron–positron annihilation, High Energy Physics::Phenomenology, Scalar (mathematics), Supersymmetry, law.invention, Nuclear physics, law, Neutralino, High Energy Physics::Experiment, Neutrino, Collider, Particle Physics - Experiment, Minimal Supersymmetric Standard Model
Abstract: A search for scalar particles and neutralinos such as those predicted by supersymmetric models has been performed using a data sample of 4.4 million hadronic Z 0 decays recorded by the OPAL detector at the e + e − collider LEP. The production of such particles typically leads to event topologies consisting of an acoplanar pair of jets, or of a mono-jet, accompanied by sizeable missing energy owing to neutrinos and other undetectable neutral particles. Limits are obtained, at the 95% confidence level, on the masses and production rates of scalar particles produced in association with the Z 0 . Limits are also placed on neutralino production, for which an additional possible signature is also studied, events containing a single observed photon. Within the Minimal Supersymmetric Standard Model, the mass of the lightest neutralino is found to be larger than 12.5 GeV/ c 2 at 95% C.L., provided that tan β is larger than 1.5.
Published: 1996
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31. Spiralling of particles by suspension feeders in a small lake-outlet stream

Author: Constantine P. Joicey, Björn Malmqvist, and Roger S. Wotton
Subjects: Hydrology, chemistry.chemical_classification, biology, Ecology, fungi, STREAMS, biology.organism_classification, Suspension (chemistry), Water column, chemistry, Midge, Animal Science and Zoology, Organic matter, Black fly, Ecology, Evolution, Behavior and Systematics
Abstract: Suspension feeders in streams trap particles from the water column and their egesta can be captured by other individuals downstream. The resultant retention and cycling of organic matter has been termed spiralling. We investigated its significance in a lake-outlet stream that had dense aggregations of suspension-feeding black fly and midge larvae in a thin film of water. We examined the abundance of dye particles, added as a pulse, in larval guts at six sites along the outlet stream (0.15–6.94 m from the top of the dam). Samples were taken 15 min, 60 min, and 24 h after the dye had been added. From samples taken after 15 min we estimated the average spiralling length to be 5.6 m. After 24 h very few particles remained, but there were significantly more in both black fly and midge larvae at sites downstream than in those upstream.
Published: 1996
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32. J/ $\psi$ and $\psi^\prime$ production in hadronic ${\rm Z}^0$ decays

Author: Gunter Wolf, R. Lahmann, D. C. Imrie, M. Palazzo, I. J. Bloodworth, R. Bartoldus, S. Wotton, H. O. Ogren, Christoph Geich-Gimbel, J. Lauber, P. Poffenberger, E.K.G. Sarkisian, P. S. Wells, David E. Plane, G. P. Siroli, J. King, Frank Fiedler, D. Hochman, Terry Richard Wyatt, M. Hapke, S. Yamashita, P. Igo-Kemenes, Yoram Rozen, J. E. Bloomer, M. Foucher, E. A. Mckigney, D. E. Hutchcroft, Dixit, Matthias Schröder, F. Strumia, Gideon Bella, G.Marco Dallavalle, P. Schütz, T. J. Smith, K. Stephens, C. H. Shepherd-Themistocleous, B. Stockhausen, Paul Kyberd, F. K. Loebinger, P. W. Jeffreys, W.John McDonald, W. P. Lai, D. Chrisman, H. Lafoux, V. Gibson, H. Jeremie, F. X. Gentit, P. Scharff-Hansen, D. R. Ward, T. Kress, M. J. Oreglia, H. J. Burckhart, Jacqueline Batley, D. Karlen, R. E. Hughes-Jones, S. Braibant, Stefan Kluth, Joleen Pater, J. E. Conboy, A. Fürtjes, C. Burgard, Shlomit Tarem, S. B. Anderson, P. Szymanski, Gabriella Pasztor, P. Bright-Thomas, J. M. Roney, S. L. Chu, R. Giacomelli, C. M. Hawkes, A. M. Smith, Daniel Lellouch, Stephen Lloyd, Robert M Brown, C. J. Oram, R. D. Heuer, G. Vasseur, S. M. Gascon-Shotkin, Takehiko Mori, Fabrizio Fabbri, J. J. Ward, P. Vikas, J. R. Carter, Madjid Boutemeur, G. A. Beck, Achim Stahl, G. N. Patrick, Tara Shears, G. A. Snow, C. P. Ward, T. Omori, A. I. McNab, N. J. Oldershaw, C. Hartmann, D. M. Strom, C. Stegmann, B. Lorazo, J. Goldberg, U. C. Dunwoody, D. Lanske, Ehud Duchovni, Otmar Biebel, H. Fukui, E. do Couto e Silva, H. Mes, S. Söldner-Rembold, P. Gagnon, P. A. Hart, Stan Bentvelsen, B. Nellen, R. Rylko, I. P. Duerdoth, V. Zacek, James Pinfold, D. L. Wagner, M. Jimack, D. G. Fong, C. Lewis, P. G. Estabrooks, A. Sittler, M. J. Pearce, A. Joly, R. K. Keeler, P. Fath, F. S. Merritt, F. Wäckerle, Thomson, J. Gascon, S. W. O'Neale, Georges Azuelos, T. Hilse, O. Schaile, D. M. Gingrich, Sven Menke, E. Tsur, S. W. Gensler, K. J. Anderson, P. M. Watkins, Hans-Christian Schultz-Coulon, H. G. Evans, H. M. Bosch, Randall Sobie, A. M. Rossi, M. J. Goodrick, I. Cohen, S. J. Hillier, Michael Schulz, G. D. Lafferty, T. Kobayashi, P. Weber, O. Runolfsson, B. Schmitt, J. Letts, M. Starks, R. Howard, A. Malik, Norbert Wermes, T. Behnke, J. Palinkas, T. Tsukamoto, J. W. Gary, W. R. Gibson, K. W. Bell, John Allison, P. Berlich, U. Müller, J. P. Pansart, T. W. Pritchard, Sherry Towers, Hildreth, T. Kawamoto, J. Steuerer, C. Y. Chang, Shlomo Dado, H. M. Fischer, D. Axen, A. Jawahery, A. Michelini, G. W. Wilson, J. C. Hill, Misao Sasaki, C. Beeston, C. Darling, A. J. Martin, D. S. Koetke, B. T. Bouwens, Claudio Grandi, M. Hauschild, Marcello Mannelli, Guenter Duckeck, M. Rosvick, D. R. Rust, David G. Charlton, C. Markus, B. C. Shen, P. Mättig, R. G. Kellogg, Paolo Giacomelli, Shoji Asai, M. Hansroul, E. Lefebvre, Lorne Levinson, Peter Sherwood, P. Taras, Michael Kobel, Alexander Wagner, Siegfried Bethke, A. S. Turcot, E. H. Vokurka, A. K. Honma, B. Nijjhar, W. G. Scott, S. A. Robins, P. D. Phillips, Andris Skuja, J. Bechtluft, Csaba Hajdu, F. Odorici, Stefano Marcellini, Gilles Beaudoin, C. K. Hargrove, J. Ludwig, G. D. Long, K. Runge, J. A. McKenna, P. Bock, Roger Barlow, A. M. Lee, A. Skillman, R. J. Homer, Richard Nisius, Giora Mikenberg, M. Tecchio, R. Bürgin, E. von Törne, Tetsuro Mashimo, B. Fabbro, Gregor Herten, Marco Cuffiani, Dezso Horvath, M. J. Losty, B. Wilkens, Reda Tafirout, Margret Fincke-Keeler, Jean-Arcady Meyer, S. G. Clowes, Julie Kirk, J. E. Pilcher, M. Fierro, J. E.G. Edwards, N. I. Geddes, W. Gorn, N. L. Rodning, B. Poli, O. C. Cooke, J. von Krogh, R. J. Hawkings, L. A. del Pozo, C. Sbarra, G. Yekutieli, A. A. Carter, Ron Folman, Roger Jones, B. J. King, P. Utzat, M. G. Rison, T. J. McMahon, J. Schwiening, R. K. Carnegie, J. A. Wilson, P. E.L. Clarke, M. K. Jones, J. P. Martin, S. Orito, M. Tscheulin, S. De Jong, U. Jost, R. Mir, Sachio Komamiya, H. Takeda, Theodoros Geralis, F. G. Oakham, E. L. Barberio, E. Ros, A. T. Watson, D. Rigby, R. J. Hemingway, B. W. Kennedy, P. Jovanovic, Austin Ball, Peter Krieger, Manuella Vincter, Alessandro Montanari, Robert Wayne Springer, C. Dallapiccola, T. P. Kokott, A. Luig, N. Altekamp, D. J. Miller, W. Matthews, H. Przysiezniak, E. K. U. Gross, A. Gaidot, T. Wlodek, M. Sproston, N. Tesch, N. K. Watson, W. Mohr, A. Posthaus, M. F. Turner-Watson, M. Morii, Peter R Hobson, D. L. Rees, A. N. Bell, F. Scharf, German Martinez, A. D. Schaile, P. Routenburg, J. G. Layter, C. Charlesworth, Stefania Xella, G. G. Hanson, G. Giacomelli, P. Schenk, R. Kowalewski, Rick J. Van Kooten, Frans Meijers, K. Ametewee, Gideon Alexander, Paolo Capiluppi, and Silvia Arcelli
Subjects: Nuclear physics, Physics, Particle physics, Physics and Astronomy (miscellaneous), Meson, Electron–positron annihilation, High Energy Physics::Phenomenology, Hadron, High Energy Physics::Experiment, B meson, Production rate, Lepton
Abstract: The production of J/psi mesons in Z(0) decays is studied using 3.6 million hadronic events recorded by the OPAL detector at LEP. The inclusive Z(0) to J/psi and b-quark to J/psi branching ratios are measured from the total yield of J/psi mesons, identified from their decays into lepton pairs. The J/psi momentum distribution is used to study the fragmentation of b-quarks. The production rate of psi' mesons, identified from their decays into a J/psi and a pi(+)pi(-) pair, is measured as well. The following results are obtained:Br(Z(0)-->J/psi X) = (3.9 +/- 0.2 +/- 0.3). 10(-3) and Br(Z(0)-->psi' X) = (1.6 +/- 0.3 +/- 0.2). 10(-3),where the first error is statistical and the second systematic. Finally the J/psi sample is used to reconstruct exclusive b-hadron decays and calculate the corresponding b-hadron branching ratios and masses.
Published: 1996
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33. Search for a narrow resonance in Z0 decays into hadrons and isolated photons

Author: M. Hapke, Sachio Komamiya, Theodoros Geralis, E. Ros, A. T. Watson, O. C. Cooke, R. Bartoldus, T. P. Kokott, A. Luig, Daniel Lellouch, H. O. Ogren, A. Joly, H. M. Fischer, M. J. Oreglia, Christoph Geich-Gimbel, Takehiko Mori, P. S. Wells, V. Zacek, Koji Yoshimura, P. Weber, J. E. Bloomer, W. J. McDonald, A. Michelini, J. von Krogh, B. C. Shen, Andris Skuja, D. Axen, A. Jawahery, F. X. Gentit, J. E. Conboy, A. Fürtjes, Peter Sherwood, E. Lefebvre, S. Yamashita, P. Igo-Kemenes, I. J. Bloodworth, S. Petzold, G. D. Long, R. J. Hawkings, Alexander Wagner, F. Odorici, P. A. Hart, J. Lauber, H. Jeremie, G. N. Patrick, Silvia Arcelli, J. Ludwig, K. Runge, P. Bock, F. Strumia, Gunter Wolf, P. Gagnon, S. A. Robins, D. L. Rees, Tetsuro Mashimo, R. E. Hughes-Jones, J. Allison, B. Nijjhar, Siegfried Bethke, A. K. Honma, M. J. Pearce, A. Sittler, B. Stockhausen, Paul Kyberd, F. K. Loebinger, L. A. del Pozo, D. E. Hutchcroft, C. Dallapiccola, J. Steuerer, Yoram Rozen, M. F. Turner-Watson, H. M. Bosch, F. Scharf, German Martinez, R. Van Kooten, M. Foucher, E. A. Mckigney, Otmar Biebel, M. Morii, Peter R Hobson, T. J. McMahon, Joleen Pater, V. Gibson, S. L. Chu, J. R. Carter, W. Gorn, W. G. Scott, A. D. Schaile, F. S. Merritt, R. Giacomelli, W. P. Lai, N. Altekamp, W. Matthews, P. Routenburg, R. Howard, J. S. White, N. J. Oldershaw, Junichi Kanzaki, D. Karlen, C. Burgard, E. do Couto e Silva, J. Schwiening, J. P. Pansart, R. K. Carnegie, S. Wotton, M. A. Thomson, Dave Charlton, T. R. Wyatt, A. S. Turcot, D. J. Miller, R. J. Barlow, J. M. Roney, S. M. Gascon-Shotkin, C.J. Beeston, T. G. Shears, U. Müller, H. Mes, J. Bechtluft, R. Lahmann, D. C. Imrie, J. A. McKenna, M. Palazzo, I. P. Duerdoth, A. J. Martin, G. D. Lafferty, A. Gaidot, J. A. Wilson, R. Bürgin, S. G. Clowes, A. I. McNab, Sven Menke, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, T. Wlodek, D. Chrisman, M. Sproston, P. Fath, J. Goldberg, F. Wäckerle, J. Letts, M. Fierro, J. E.G. Edwards, Ekg Sarkisyan, G. P. Siroli, J. King, O. Schaile, D. M. Gingrich, P. W. Jeffreys, D. M. Strom, D. Rigby, R. J. Hemingway, Madjid Boutemeur, Volker Blobel, T. Behnke, B. Nellen, G. Giacomelli, Norbert Wermes, Eilam Gross, Sherry Towers, T. Kawamoto, P. Scharff-Hansen, C. K. Hargrove, B. W. Kennedy, C. Darling, T. J. Smith, Matthew Evans, M. Starks, P. Berlich, Gideon Bella, N. Tesch, M. Gruwé, P. Jovanovic, S. Orito, C. H. Shepherd-Themistocleous, H. J. Burckhart, M. Rosvick, Jacqueline Batley, Austin Ball, P. Bright-Thomas, A. M. Rossi, Matthias Schröder, P. G. Estabrooks, R. K. Keeler, C. Sbarra, Peter Krieger, P. Mättig, R. W. Springer, H. G. Evans, H. Fukui, R. Rylko, Richard Nisius, M. Thiergen, Stephen Lloyd, J. J. Ward, Manuella Vincter, R. G. Kellogg, Csaba Hajdu, Stefano Marcellini, M. J. Goodrick, I. Cohen, Alessandro Montanari, Hans-Christian Schultz-Coulon, Robert M Brown, Shoji Asai, Marco Cuffiani, T. Omori, P. Vikas, H. Lafoux, D. Lanske, A. M. Smith, G. W. Wilson, G. Vasseur, M. Hauschild, P. M. Watkins, Randall Sobie, Georges Azuelos, E. Tsur, Michael Schulz, C. M. Hawkes, U. Jost, R. Mir, R. D. Heuer, N. K. Watson, Fabrizio Fabbri, B. Lorazo, N. I. Geddes, Michael Hildreth, C. Markus, M. Verzocchi, K. W. Bell, Ehud Duchovni, G. Yekutieli, N. L. Rodning, J. C. Hill, Misao Sasaki, T. Hilse, H. Takeda, D. R. Rust, E. H. Vokurka, O. Runolfsson, M. Jimack, James Pinfold, B. Poli, D. G. Fong, C. Lewis, F. G. Oakham, Stefan Kluth, E. L. Barberio, Shlomit Tarem, J. Gascon, A. M. Lee, A. A. Carter, Ron Folman, F. Palmonari, Roger Jones, M. Tecchio, E. von Törne, W. Mohr, S. W. Gensler, Gregor Herten, A. Posthaus, Claudio Grandi, A. Malik, J. W. Gary, T. Kobayashi, Guenter Duckeck, B. Wilkens, D. S. Koetke, Marcello Mannelli, J. E. Pilcher, P. Utzat, M. G. Rison, R. Kowalewski, K. Ametewee, Gideon Alexander, Paolo Capiluppi, S. B. Anderson, P. Szymanski, Stan Bentvelsen, C. Hartmann, D. E. Plane, Stephen Hillier, G. M. Dallavalle, J. G. Layter, C. Charlesworth, W. R. Gibson, Stefania Xella, B. T. Bouwens, J. Palinkas, Shlomo Dado, G. G. Hanson, Lorne Levinson, Giora Mikenberg, P. D. Phillips, P. Schenk, S. Braibant, Gabriella Pasztor, M. S. Dixit, Frans Meijers, Gilles Beaudoin, G. A. Snow, C. P. Ward, P. E.L. Clarke, M. K. Jones, A. Skillman, S. Söldner-Rembold, Paolo Giacomelli, J. P. Martin, M. Tscheulin, M. Hansroul, S. De Jong, H. Przysiezniak, A. N. Bell, Reda Tafirout, R. J. Homer, Achim Stahl, C. Y. Chang, B. Schmitt, P. Taras, Michael Kobel, Julie Kirk, P. Poffenberger, P. Schütz, S. W. O'Neale, K. J. Anderson, K. Stephens, D. R. Ward, T. Kress, and Frank Fiedler
Subjects: Quark, Physics, Particle physics, Physics and Astronomy (miscellaneous), Electron–positron annihilation, High Energy Physics::Phenomenology, Hadron, Scalar (mathematics), Bottom quark, Resonance (particle physics), Standard Model, Nuclear physics, Higgs boson, High Energy Physics::Experiment, Particle Physics - Experiment
Abstract: A search for the hadronic decay of a hypothetical resonance S0 in the process e+e−→γ + hadrons at Z0 energies is reported. Particular care is taken to optimise the sensitivity to a scalar resonance decaying into bottom quarks, as expected for Higgs production, e+e−→Z0→H0γ with$H^0 \to b\bar b$, in the Standard Model or some of its extensions. No evidence for such a resonance is observed in a sample of about 5 million produced Z0’s. The results are interpreted in terms of models of non-standard Higgs production. An update of a search for a resonance produced in association with hadrons and the subsequent resonance decay into two photons is also presented.
Published: 1996
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34. Colloids, Bubbles, and Aggregates: A Perspective on Their Role in Suspension Feeding

Author: R. S. Wotton
Subjects: Exopolymer, Ecology, digestive, oral, and skin physiology, Aquatic Science, Biology, Particulates, Suspension (chemistry), Particle aggregation, Colloid, Water column, Chemical engineering, Dissolved organic carbon, Ecology, Evolution, Behavior and Systematics, Marine snow
Abstract: Suspension feeders capture a wide range of materials from water currents, and the type of food subsequently ingested varies with the catching device and with the animal's ability to be selective. Black fly larvae are examples of non-selective suspension feeders that ingest particulate and dissolved organic matter (POM and DOM). The DOM includes colloids originally produced as mucopolysaccharide (exopolymer) exudates from cells. Colloidal exopolymer particles (CEPs, those
Published: 1996
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35. Measurement of the branching ratio

Author: F. S. Merritt, Otmar Biebel, D. L. Wagner, D. E. Hutchcroft, C. Dallapiccola, O. C. Cooke, I. J. Bloodworth, J. Bechtluft, D. M. Strom, C. Stegmann, H. M. Fischer, H. Fukui, R. Rylko, Margret Fincke-Keeler, A. Michelini, D. R. Rust, J. von Krogh, Yoram Rozen, R. W. Springer, R. Lahmann, D. C. Imrie, M. Palazzo, J. Letts, M. Foucher, R. J. Sobie, N. Altekamp, R. Howard, P. E.L. Clarke, Norbert Wermes, Sherry Towers, J. P. Pansart, S. Braibant, Gabriella Pasztor, P. Gagnon, R. J. Hawkings, T. Kawamoto, R. Bartoldus, E. Lefebvre, G. P. Siroli, J. King, P. Igo-Kemenes, M. K. Jones, W. Matthews, A. M. Lee, T. Behnke, J. Steuerer, S. A. Robins, P. S. Wells, J. Allison, D. J. Miller, H. O. Ogren, A. T. Watson, J. P. Martin, S. Orito, L. A. del Pozo, J. E. Bloomer, Joleen Pater, C. Y. Chang, H. Jeremie, M. Tscheulin, M. A. Thomson, M. Rosvick, Christoph Geich-Gimbel, P. Scharff-Hansen, Stefan Kluth, Shlomit Tarem, M. Tecchio, E. von Törne, A. Sittler, C. Burgard, F. Odorici, S. De Jong, Sachio Komamiya, Theodoros Geralis, Georges Azuelos, D Darlen, J. R. Carter, R. E. Hughes-Jones, C. P. Ward, E. K. U. Gross, Gideon Bella, A. Gaidot, T. Wlodek, M. Sproston, C. H. Shepherd-Themistocleous, C. Sbarra, C. J. Oram, E. Ros, W. R. Gibson, S. L. Lloyd, F. X. Gentit, Gregor Herten, P. Taras, E. Tsur, A. Joly, S. Söldner-Rembold, H. M. Bosch, A. S. Turcot, Michael Kobel, M. Hapke, J. E. Conboy, A. Fürtjes, H. J. Burckhart, Jacqueline Batley, K. W. Bell, G. Yekutieli, T. P. Kokott, C. Darling, V. Gibson, A. Luig, N. I. Geddes, J. A. McKenna, B. Wilkens, J. C. Hill, B. T. Bouwens, N. Tesch, H. Przysiezniak, A. M. Smith, Michael Hildreth, Paolo Giacomelli, G.A Show, Gunter Wolf, Silvia Arcelli, Satoru Yamashita, M. Hansroul, W.J. McDonald, D. Rigby, R. J. Hemingway, A. A. Carter, Ron Folman, A. N. Bell, E. do Couto e Silva, U. Müller, T. J. Smith, N. L. Rodning, K. Stephens, G. Vasseur, B. Lorazo, B. Poli, R. M. Brown, D. Axen, Lorne Levinson, A. Jawahery, P. Mättig, Richard Nisius, M. J. Oreglia, S. Wotton, J. E. Pilcher, T. Omori, Shoji Asai, B. W. Kennedy, B. J. King, C. M. Hawkes, P. D. Phillips, Julie Kirk, T. Hilse, O. Schaile, B. C. Shen, Andris Skuja, A. J. Martin, J. Palinkas, Peter Sherwood, Marco Cuffiani, Daniel Lellouch, H. Mes, N. J. Oldershaw, D. L. Rees, Shlomo Dado, I. P. Duerdoth, P. Fath, G. D. Long, R. J. Homer, R. G. Kellogg, P. Utzat, Gilles Beaudoin, A. Skillman, P. Jovanovic, Austin Ball, M. G. Rison, Alexander Wagner, Csaba Hajdu, Peter Krieger, Takehiko Mori, Sven Menke, Siegfried Bethke, Tetsuro Mashimo, J. Ludwig, K. Runge, P. Bock, A. K. Honma, A. I. McNab, J. Goldberg, G. N. Patrick, F. Scharf, S. B. Anderson, B. Nellen, German Martinez, Stefano Marcellini, S. M. Gascon-Shotkin, T. J. McMahon, Manuella Vincter, J. Schwiening, G. G. Hanson, Alessandro Montanari, M. F. Turner-Watson, P. Szymanski, O. Runolfsson, M. Morii, Peter R Hobson, W. G. Scott, R. D. Heuer, G. A. Beck, Achim Stahl, J. Lauber, J. W. Gary, B. Stockhausen, Paul Kyberd, Reda Tafirout, F. K. Loebinger, Fabrizio Fabbri, A. D. Schaile, R. Van Kooten, S. L. Chu, F. Strumia, H. G. Evans, M. J. Goodrick, I. Cohen, N. K. Watson, G. Mikenberg, U. Jost, R. K. Carnegie, R. Mir, J. A. Wilson, P. Poffenberger, Dave Charlton, R. Giacomelli, C. K. Hargrove, P. Routenburg, P. Schütz, W. Gorn, D. R. Ward, T. Kress, P. Weber, Stan Bentvelsen, Dezso Horvath, U. C. Dunwoody, Claudio Grandi, B. Schmitt, J. M. Roney, P. A. Hart, G. Giacomelli, P. Schenk, M. Starks, C.J. Beeston, M. J. Losty, Jean-Arcady Meyer, T. G. Shears, E. A. Mckigney, Abish Malik, Ekg Sarkisyan, P. W. Jeffreys, B. Nijjhar, T. Kobayashi, H. Takeda, C. Hartmann, D. E. Plane, F. Wäckerle, R. Bürgin, B. Fabbro, M. Sasaki, D. M. Gingrich, M. S. Dixit, Frans Meijers, M. J. Pearce, G. M. Dallavalle, W. P. Lai, F. G. Oakham, G. W. Wilson, W. Mohr, P. Berlich, James Pinfold, M. Hauschild, Hans-Christian Schultz-Coulon, A. Posthaus, P. Bright-Thomas, Michael Schulz, E. L. Barberio, A. M. Rossi, D. G. Fong, C. Lewis, J. Gascon, Frank Fiedler, D. Hochman, J. J. Ward, T. Tsukamoto, P. Vikas, D. Lanske, C. Markus, Matthias Schröder, T. W. Pritchard, V. Zacek, H. Lafoux, T. R. Wyatt, D. S. Koetke, G. D. Lafferty, Guenter Duckeck, R. J. Barlow, Marcello Mannelli, R. W.L. Jones, Madjid Boutemeur, S. G. Clowes, M. Fierro, J. E.G. Edwards, J. G. Layter, S. W. O'Neale, E. H. Vokurka, P. G. Estabrooks, R. K. Keeler, P. M. Watkins, C. Charlesworth, K. J. Anderson, Stefania Xella, D. Chrisman, R. Kowalewski, K. Ametewee, Gideon Alexander, Paolo Capiluppi, Ehud Duchovni, M. Jimack, S. W. Gensler, and S. J. Hillier
Subjects: Nuclear physics, Physics, Nuclear and High Energy Physics, Branching fraction, Electron–positron annihilation, Detector, Weak interaction, Charged current, Universality (dynamical systems)
Abstract: The branching ratio of the τ− → e−νeντ decay mode has been measured with the OPAL detector to be (17.78 ± 0.10 ±0.09)% where the first error is statistical and the second is systematic. The branching ratio, together with other measurements, has been used to test e — μ and μ — τ universality in the charged current weak interaction.
Published: 1996
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36. Measurement of the average b-baryon lifetime and the product branching ratio $$f(b \to \Lambda _b ) \cdot BR(\Lambda _b \to \Lambda \ell ^ - \bar vX)$$

Author: R. Lahmann, D. C. Imrie, C. Y. Chang, P. Taras, Michael Kobel, G. P. Siroli, J. King, I. J. Bloodworth, O. C. Cooke, S. L. Chu, Stefan Kluth, M. Hapke, D. Axen, A. Jawahery, Shlomit Tarem, J. C. Clayton, M. Settles, Julie Kirk, H. Lafoux, R. Kowalewski, D. E. Hutchcroft, Gideon Bella, C. J. Oram, G. W. Wilson, P. Igo-Kemenes, Yoram Rozen, J. von Krogh, M. Hauschild, H. J. Burckhart, Jacqueline Batley, H. Mes, K. Stephens, M. Foucher, M. J. Oreglia, H. Jeremie, K. Ametewee, C. Markus, R. E. Hughes-Jones, R. J. Hawkings, R. Bartoldus, Peter Sherwood, V. Gibson, Tara Shears, Alexander Wagner, Frank Fiedler, D. Hochman, Gunter Wolf, F. X. Gentit, Gideon Alexander, Paolo Capiluppi, L. A. del Pozo, I. P. Duerdoth, Kiyotomo Kawagoe, P. Fath, Junichi Kanzaki, D. Karlen, H. O. Ogren, Christoph Geich-Gimbel, D. R. Ward, T. Kress, T. J. McMahon, J. Schwiening, P. S. Wells, U. C. Dunwoody, P. A. Hart, J. Ludwig, P. Poffenberger, K. Runge, P. Bock, R. K. Carnegie, C. Burgard, E. do Couto e Silva, N. J. Oldershaw, R.J. Akers, J. R. Carter, Terry Richard Wyatt, G. N. Patrick, J. A. Wilson, M. J. Pearce, Ehud Duchovni, J. Steuerer, P. Schütz, S. Wotton, B. Stockhausen, Paul Kyberd, F. K. Loebinger, Sven Menke, P. Weber, O. Schaile, S. G. Clowes, S. B. Anderson, P. Szymanski, A. Gaidot, P. Scharff-Hansen, M. Fierro, J. E.G. Edwards, Otmar Biebel, D. L. Wagner, R. W. Springer, M. Jimack, J. E. Conboy, A. Fürtjes, Sachio Komamiya, Theodoros Geralis, A. I. McNab, J. Goldberg, H. Deng, S. Braibant, P. W. Jeffreys, M. Starks, E. Ros, A. T. Watson, A. J. Martin, B. Nellen, D. L. Rees, J. Letts, F. Palmonari, Silvia Arcelli, S. W. Gensler, S. J. Hillier, T. Kobayashi, Georges Azuelos, Norbert Wermes, Sherry Towers, R. Giacomelli, F. Scharf, A. M. Smith, T. Kawamoto, F. S. Merritt, C. Darling, P. Bright-Thomas, T. J. Smith, C. Sbarra, Matthias Schröder, G. A. Snow, C. P. Ward, E. Lefebvre, Stan Bentvelsen, G. Vasseur, S. Orito, B. Lorazo, M. Rosvick, Marco Cuffiani, S. W. O'Neale, K. W. Bell, K. J. Anderson, A. D. Schaile, H. G. Evans, M. J. Goodrick, S. Söldner-Rembold, I. Cohen, T. P. Kokott, A. Luig, Andris Skuja, P. Gagnon, A. Buijs, F. Odorici, D. M. Strom, J. C. Hill, Misao Sasaki, G. Yekutieli, Dave Charlton, J. J. Ward, P. Vikas, D. Lanske, P. Mättig, Shoji Asai, B. C. Shen, G. D. Long, Tetsuro Mashimo, Paolo Giacomelli, M. Hansroul, A. A. Carter, C. Stegmann, J. A. McKenna, Gregor Herten, Siegfried Bethke, A. Joly, Ron Folman, Roger Jones, Shlomo Dado, N. K. Watson, Gordon H. Hanson, A. K. Honma, Stephen Lloyd, B. Nijjhar, G. T. Zorn, W. G. Scott, M. Tecchio, C. M. Hawkes, B. Wilkens, G. Giacomelli, A. S. Turcot, B. J. King, H. Fukui, P. Utzat, R. Bürgin, B. Fabbro, M. W. Redmond, M. G. Rison, C. H. Shepherd-Themistocleous, E. A. Mckigney, J. Bechtluft, M. F. Turner-Watson, J. P. Pansart, T. Hilse, M. Morii, W. Gorn, H. M. Bosch, Wolfram Dietrich Zeuner, John Allison, P. Schenk, Peter R Hobson, Giora Mikenberg, Daniel Lellouch, Takehiko Mori, J. E. Pilcher, N. I. Geddes, R. J. Homer, O. Runolfsson, P. Routenburg, U. Müller, M. J. Losty, R. G. Kellogg, W. Mohr, A. Posthaus, W. P. Lai, M. S. Dixit, Stefano Marcellini, N. L. Rodning, C. Beeston, James Pinfold, Claudio Grandi, B. Poli, D. G. Fong, W. Matthews, M. A. Thomson, Frans Meijers, J. Gascon, V. Zacek, G. A. Beck, C. K. Hargrove, E. K. U. Gross, A. Malik, T. Wlodek, R. Howard, Achim Stahl, P. Teixeira-Dias, M. Sproston, J. W. Gary, D. S. Koetke, Marcello Mannelli, J. E. Duboscq, J. M. Roney, T. Tsukamoto, N. Tesch, T. Behnke, S. M. Gascon-Shotkin, J. G. Layter, Hans-Christian Schultz-Coulon, Randall Sobie, Michael Schulz, G. D. Lafferty, B. Schmitt, Madjid Boutemeur, C. Charlesworth, Margret Fincke-Keeler, T. W. Pritchard, P. E.L. Clarke, M. K. Jones, J. P. Martin, P. G. Estabrooks, M. Tscheulin, R. K. Keeler, Guenter Duckeck, S. De Jong, A. M. Rossi, H. Przysiezniak, P. M. Watkins, H. M. Fischer, A. Michelini, S. A. Robins, C. Dallapiccola, J. D. Gillies, N. Altekamp, R. J. Barlow, D. J. Miller, R. Mir, J. Lauber, F. G. Oakham, E. L. Barberio, D. Rigby, R. J. Hemingway, B. W. Kennedy, P. Jovanovic, Austin Ball, Peter Krieger, Manuella Vincter, Alessandro Montanari, D. R. Rust, C. Hartmann, D. E. Plane, G. M. Dallavalle, A. M. Lee, E. von Törne, W. R. Gibson, A. Beck, R. Van Kooten, R. M. Brown, Lorne Levinson, P. D. Phillips, Gilles Beaudoin, A. Skillman, F. Wäckerle, Reda Tafirout, D. M. Gingrich, P. Berlich, M. Fanti, R. D. Heuer, and Fabrizio Fabbri
Subjects: Physics, Quark, Particle physics, Muon, Physics and Astronomy (miscellaneous), Branching fraction, High Energy Physics::Phenomenology, Lambda, Baryon, Nuclear physics, High Energy Physics::Experiment, Baryon number, Impact parameter, Nuclear Experiment, Lepton
Abstract: The average lifetime of b-flavoured baryons measured with the OPAL detector is updated to include data collected between 1990 and 1994 at LEP. Bottom-flavoured baryons that decay semileptonically and produce aΛ baryon are identified through the correlation of the baryon number of theΛ and the electric charge of the lepton. To measure the lifetime, the decay point of the b baryon is estimated by theΛ-lepton vertex, and the observed distribution of decay lengths is fitted simultaneously in 874 right-sign and 384 wrong-sign combinations. In a separate method, the impact parameter distribution of the leptons is fitted in a subset of these data. When the two results are combined, taking correlations into account, the average b-baryon lifetime is found to be τ=1.16±0.11(stat.)±0.06(syst.) ps. Using the same data, the product branching ratio is measured to be$\begin{gathered} \hfill f(b \to \Lambda _b ) \cdot BR(\Lambda _b \to \Lambda \ell ^ - \bar vX) = (2.91 \pm 0.23(stat.) \\ \hfill \pm 0.25(stat.)) \cdot 10^{ - 3} \\ \end{gathered} $, where the symbolf(b→Λb) is the fraction of b quarks from Z0 decays forming b baryons,Λb represents all b-flavoured baryons and l is either an electron or a muon.
Published: 1995
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37. Measurement of the τ−→h − h + h − v τ and τ−→h − h + h −≥1π0 v τ branching ratios

Author: Madjid Boutemeur, G. D. Long, Tetsuro Mashimo, P. G. Estabrooks, R. K. Keeler, W. Gorn, P. M. Watkins, R. Bartoldus, Otmar Biebel, D. L. Wagner, H. O. Ogren, C. Y. Chang, S. Braibant, Christoph Geich-Gimbel, H. Deng, G. G. Hanson, P. Taras, G. Giacomelli, W. R. Gibson, G. A. Snow, C. P. Ward, N. J. Oldershaw, F. X. Gentit, J. E. Conboy, J. Letts, P. Schenk, Michael Kobel, A. Beck, S. Söldner-Rembold, Norbert Wermes, A. Fürtjes, R.J. Akers, R. Kowalewski, Sherry Towers, M. S. Dixit, T. Kawamoto, G. A. Beck, R. M. Brown, Lorne Levinson, Frans Meijers, Achim Stahl, P. Teixeira-Dias, P. D. Phillips, P. E.L. Clarke, M. K. Jones, Gilles Beaudoin, P. Igo-Kemenes, Julie Kirk, H. Lafoux, A. Skillman, S. Orito, M. Rosvick, F. Palmonari, O. Schaile, K. Ametewee, R. G. Kellogg, Silvia Arcelli, J. P. Martin, M. Tscheulin, B. Schmitt, S. De Jong, H. Jeremie, N. K. Watson, R. Lahmann, D. C. Imrie, Matthias Schröder, Gideon Alexander, Paolo Capiluppi, R. E. Hughes-Jones, Reda Tafirout, M. Fanti, J. Steuerer, H. Przysiezniak, V. Gibson, E. A. Mckigney, O. C. Cooke, Margret Fincke-Keeler, F. S. Merritt, M. Hapke, M. Starks, G. P. Siroli, J. King, D. E. Hutchcroft, C. Dallapiccola, P. Scharff-Hansen, Sachio Komamiya, W. P. Lai, Theodoros Geralis, E. Ros, A. T. Watson, E. do Couto e Silva, S. Marcllini, J. D. Gillies, W. Mohr, A. Posthaus, Dave Charlton, J. Bechtluft, J. A. McKenna, Shlomo Dado, J. von Krogh, R. J. Hawkings, Ehud Duchovni, A. M. Smith, G. Vasseur, R. Howard, C. Hartmann, D. E. Plane, N. Altekamp, B. Lorazo, James Pinfold, D. G. Fong, P. Poffenberger, T. J. Smith, K. Stephens, P. Schütz, L. A. del Pozo, B. C. Shen, R. Bürgin, B. Fabbro, G. M. Dallavalle, G. W. Wilson, M. Hauschild, J. G. Layter, Sven Menke, H. Mes, M. J. Oreglia, J. P. Pansart, Giora Mikenberg, J. Gascon, T. P. Kokott, A. Luig, T. J. McMahon, D. J. Miller, C. Markus, D. L. Rees, C. Charlesworth, A. Malik, G. N. Patrick, U. Müller, A. J. Martin, J. Schwiening, I. P. Duerdoth, R. K. Carnegie, D. Axen, J. W. Gary, Paolo Giacomelli, R. D. Heuer, A. Jawahery, Fabrizio Fabbri, D. S. Koetke, F. Scharf, M. Hansroul, M. Jimack, J. A. Wilson, Marcello Mannelli, J. E. Duboscq, S. W. Gensler, P. Fath, Siegfried Bethke, A. K. Honma, A. D. Schaile, Kiyotomo Kawagoe, Gideon Bella, Marco Cuffiani, S. J. Hillier, Peter Sherwood, A. Buijs, T. Kobayashi, H. J. Burckhart, Alexander Wagner, Jacqueline Batley, W. Matthews, C. Sbarra, D. M. Strom, C. Stegmann, T. R. Wyatt, M. A. Thomson, J. Ludwig, K. Runge, D. R. Rust, C. H. Shepherd-Themistocleous, P. Bock, G. Yekutieli, C. K. Hargrove, H. Fukui, E. K. U. Gross, P. Weber, W. G. Scott, A. Gaidot, T. Wlodek, M. F. Turner-Watson, A. A. Carter, M. Sproston, Ron Folman, Roger Jones, P. Gagnon, U. C. Dunwoody, P. A. Hart, J. Allison, D. R. Ward, T. Kress, Gregor Herten, B. J. King, R. J. Barlow, M. Morii, P. Utzat, B. Nijjhar, S. L. Chu, R. J. Homer, Peter R Hobson, N. Tesch, G. T. Zorn, M. J. Pearce, A. M. Lee, R. Mir, M. G. Rison, B. Wilkens, S. W. O'Neale, K. J. Anderson, E. Lefebvre, E. von Törne, H. M. Bosch, S. G. Clowes, Wolfram Dietrich Zeuner, P. Routenburg, J. E. Pilcher, M. Fierro, J. E.G. Edwards, F. Odorici, Frank Fiedler, D. Hochman, P. W. Jeffreys, R. Van Kooten, P. S. Wells, J. C. Clayton, Stephen Lloyd, T. Behnke, C.J. Beeston, T. G. Shears, M. Tecchio, F. Wäckerle, J. Lauber, D. M. Gingrich, P. Berlich, P. Bright-Thomas, J. J. Ward, P. Vikas, D. Lanske, F. G. Oakham, M. J. Losty, E. L. Barberio, T. Hilse, O. Runolfsson, D. Rigby, R. J. Hemingway, B. W. Kennedy, P. Jovanovic, Claudio Grandi, Austin Ball, Peter Krieger, R. W. Springer, Manuella Vincter, Alessandro Montanari, Georges Azuelos, K. W. Bell, J. C. Hill, Misao Sasaki, J. M. Roney, G. D. Lafferty, A. Joly, M. W. Redmond, B. Stockhausen, Paul Kyberd, F. K. Loebinger, R. Giacomelli, A. I. McNab, J. Goldberg, S. M. Gascon-Shotkin, B. Nellen, H. G. Evans, M. J. Goodrick, I. Cohen, A. M. Rossi, T. Tsukamoto, Stefan Kluth, H. M. Fischer, Shlomit Tarem, A. Michelini, C. J. Oram, Gunter Wolf, S. A. Robins, S. Wotton, J. R. Carter, N. I. Geddes, N. L. Rodning, B. Poli, I. J. Bloodworth, M. Settles, Yoram Rozen, M. Foucher, Junichi Kanzaki, D. Karlen, C. Burgard, C. M. Hawkes, Daniel Lellouch, A. S. Turcot, Takehiko Mori, V. Zacek, C. Darling, P. Mättig, Shoji Asai, S. B. Anderson, P. Szymanski, Stan Bentvelsen, Hans-Christian Schultz-Coulon, Randall Sobie, Michael Schulz, T. W. Pritchard, Guenter Duckeck, and Andris Skuja
Subjects: Physics, Particle physics, Physics and Astronomy (miscellaneous), Meson, Branching fraction, Electron–positron annihilation, Analytical chemistry, Branching (polymer chemistry), Engineering (miscellaneous), Charged particle, Lepton
Abstract: The branching ratios of the τ−→h − h + h − v τ and τ−→h − h + h −≥1π0 v τ decays, whereh is either a charged π orK meson, are measured using a data sample of 87861 τ+τ− pairs collected with the OPAL detector at LEP. The two branching ratios are extracted simultaneously from a sample of three charged particle decays and found to be: $$\begin{gathered} B(\tau ^ - \to h^ - h^ + h^ - \nu _\tau ) = (9.87 \pm 0.10 \pm 0.24)\% \hfill \\ B(\tau ^ - \to h^ - h^ + h^ - \geqslant 1\pi ^0 \nu _\tau ) = (5.09 \pm 0.10 \pm 0.23)\% \hfill \\ \end{gathered}$$ where the first error is statistical and the second systematic. The branching ratio of the τ lepton into three charged particles is measured to be: $$B(\tau ^ - \to 3 - prong) = (14.96 \pm 0.09 \pm 0.22)\%$$
Published: 1995
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38. A study of QCD structure constants and a measurement of $$\alpha _s (M_{Z^0 } )$$ at LEP using event shape observables

Author: S. Braibant, H. M. Fischer, T. J. McMahon, Otmar Biebel, A. Michelini, D. L. Wagner, Gunter Wolf, F. X. Gentit, G. A. Snow, C. P. Ward, H. Deng, S. Söldner-Rembold, Reda Tafirout, S. A. Robins, P. E.L. Clarke, R. Kowalewski, J. Schwiening, M. K. Jones, G. W. Wilson, J. Letts, Frank Fiedler, D. Hochman, M. Hauschild, R. Lahmann, D. C. Imrie, J. P. Martin, E. Lefebvre, Norbert Wermes, Sherry Towers, C. Markus, R. K. Carnegie, Andris Skuja, M. Tscheulin, S. De Jong, N. J. Oldershaw, J. A. Wilson, R.J. Akers, O. Schaile, T. Kawamoto, Paolo Giacomelli, C. M. Hawkes, M. Starks, K. Ametewee, K. Stephens, F. Odorici, Daniel Lellouch, Madjid Boutemeur, M. Hansroul, S. Wotton, Matthias Schröder, Takehiko Mori, Shlomo Dado, Gideon Alexander, Paolo Capiluppi, G. P. Siroli, J. King, M. Fanti, W. R. Gibson, S. Orito, M. Rosvick, G. D. Long, Tetsuro Mashimo, P. G. Estabrooks, R. K. Keeler, V. Gibson, H. Przysiezniak, C. H. Shepherd-Themistocleous, V. Zacek, R. J. Homer, J. Steuerer, A. Beck, Gregor Herten, B. Wilkens, Lorne Levinson, J. P. Pansart, M. Hapke, R. W. Springer, J. E. Pilcher, R. Bartoldus, C. Dallapiccola, Eilam Gross, C. Sbarra, Margret Fincke-Keeler, P. M. Watkins, J. D. Gillies, P. D. Phillips, Gilles Beaudoin, Giora Mikenberg, A. Skillman, T. Hilse, D. E. Hutchcroft, W. Gorn, Hans-Christian Schultz-Coulon, D. R. Ward, T. Kress, A. M. Rossi, N. K. Watson, O. Runolfsson, Ehud Duchovni, M. Jimack, P. S. Wells, G. Yekutieli, Randall Sobie, Michael Schulz, G. D. Lafferty, R. D. Heuer, U. Müller, C. Hartmann, D. E. Plane, A. I. McNab, P. Igo-Kemenes, Georges Azuelos, M. J. Oreglia, T. Tsukamoto, Fabrizio Fabbri, G. G. Hanson, A. J. Martin, H. O. Ogren, F. Palmonari, J. C. Clayton, Silvia Arcelli, D. Axen, Christoph Geich-Gimbel, S. W. Gensler, S. J. Hillier, C. Darling, T. J. Smith, Terry Richard Wyatt, A. A. Carter, Ron Folman, T. Kobayashi, N. Altekamp, R. Van Kooten, Roger Jones, Kiyotomo Kawagoe, G. M. Dallavalle, T. W. Pritchard, J. Goldberg, K. W. Bell, H. Mes, C. Beeston, R. J. Barlow, H. Jeremie, J. R. Carter, G. N. Patrick, J. C. Hill, P. Scharff-Hansen, P. Schenk, N. I. Geddes, Claudio Grandi, Misao Sasaki, A. Jawahery, Marco Cuffiani, B. Stockhausen, Paul Kyberd, F. K. Loebinger, P. W. Jeffreys, P. Mättig, Shoji Asai, I. P. Duerdoth, P. Fath, Dave Charlton, Sachio Komamiya, Theodoros Geralis, Guenter Duckeck, B. Nellen, B. C. Shen, D. J. Miller, S. W. O'Neale, R. E. Hughes-Jones, N. L. Rodning, E. Ros, A. T. Watson, M. S. Dixit, W. Mohr, Siegfried Bethke, A. K. Honma, B. Nijjhar, A. M. Smith, Frans Meijers, W. G. Scott, F. Wäckerle, B. Poli, E. A. Mckigney, D. M. Gingrich, K. J. Anderson, J. E. Conboy, S. L. Chu, A. Fürtjes, A. Posthaus, B. J. King, P. Utzat, M. G. Rison, A. Buijs, C. K. Hargrove, G. A. Beck, P. Weber, Achim Stahl, P. Teixeira-Dias, T. P. Kokott, A. Luig, Peter Sherwood, G. Vasseur, B. Lorazo, Tara Shears, E. do Couto e Silva, W. P. Lai, Alexander Wagner, P. Berlich, D. M. Strom, R. Bürgin, B. Fabbro, C. Stegmann, I. J. Bloodworth, Stephen Lloyd, W. Matthews, P. Bright-Thomas, F. S. Merritt, J. Ludwig, G. Giacomelli, O. C. Cooke, A. S. Turcot, H. Fukui, P. Poffenberger, U. C. Dunwoody, H. G. Evans, B. Schmitt, M. A. Thomson, M. J. Goodrick, James Pinfold, P. A. Hart, Sven Menke, D. G. Fong, J. Gascon, M. J. Losty, D. R. Rust, D. Rigby, R. J. Hemingway, M. Tecchio, Robert M Brown, J. M. Roney, J. J. Ward, P. Vikas, Gideon Bella, K. Runge, P. Bock, H. J. Burckhart, J. G. Layter, Jacqueline Batley, M. Settles, Yoram Rozen, M. Foucher, P. Schütz, R. Giacomelli, I. Cohen, M. J. Pearce, D. Lanske, A. M. Lee, A. Malik, J. W. Gary, D. S. Koetke, C. Charlesworth, B. W. Kennedy, P. Jovanovic, J. Bechtluft, J. A. McKenna, Austin Ball, E. von Törne, J. von Krogh, A. Gaidot, T. Wlodek, Marcello Mannelli, J. E. Duboscq, M. Sproston, Peter Krieger, Manuella Vincter, R. J. Hawkings, L. A. del Pozo, C. Y. Chang, D. Karlen, C. Burgard, Alessandro Montanari, P. Taras, R. Mir, R. Howard, N. Tesch, T. Behnke, S. B. Anderson, Stefan Kluth, Shlomit Tarem, P. Szymanski, Michael Kobel, J. Lauber, P. Gagnon, C. J. Oram, Julie Kirk, H. Lafoux, S. G. Clowes, D. L. Rees, Stan Bentvelsen, M. Fierro, J. E.G. Edwards, F. Scharf, F. G. Oakham, G. T. Zorn, A. D. Schaile, E. L. Barberio, H. M. Bosch, Wolfram Dietrich Zeuner, A. Joly, M. F. Turner-Watson, M. Morii, M. W. Redmond, Peter R Hobson, P. Routenburg, John Allison, R. G. Kellogg, and Stefano Marcellini
Subjects: Quantum chromodynamics, Quark, Physics, Particle physics, Structure constants, Physics and Astronomy (miscellaneous), High Energy Physics::Lattice, High Energy Physics::Phenomenology, Observable, Jet (particle physics), Nuclear physics, Strong coupling, High Energy Physics::Experiment, Constant (mathematics), Engineering (miscellaneous), Event (particle physics), Particle Physics - Experiment
Abstract: The dependence of event shape cross sections on the QCD structure constantsCA,CF andTF is studied using data from the OPAL detector at LEP. The observables Thrust, Heavy Jet Mass, Total and Wide Jet Broadening are used. They allow the use ofO(αs2), resummed NLLA, and combinedO(αs2) plus resummed NLLA QCD calculations so that a comparison between the different approaches can be performed. The measured values of the structure constants are found to be consistent with standard QCD based on SU(3) and five active quark flavours. A measurement of the strong coupling constant using NLLA QCD calculations alone results in$\alpha _s (M_{Z^0 } ) = 0.113_{ - 0.008}^{ + 0.009}$, which complements our previous determinations.
Published: 1995
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39. A study of b quark fragmentation into B0 and B+ mesons at LEP

Author: Theodoros Geralis, E. Ros, S. M. Gascon-Shotkin, J. Palinkas, T. P. Kokott, A. Luig, D. Rigby, R. J. Hemingway, H. Mes, I. P. Duerdoth, Shlomo Dado, P. Fath, A. M. Rossi, F. Wäckerle, B. W. Kennedy, D. M. Gingrich, P. Jovanovic, T. Behnke, J. Steuerer, Austin Ball, Peter Krieger, P. Berlich, Manuella Vincter, Alessandro Montanari, P. W. Jeffreys, M. F. Turner-Watson, M. Morii, Peter R Hobson, P. Routenburg, Giora Mikenberg, U. Jost, R. Mir, Reda Tafirout, Madjid Boutemeur, P. Igo-Kemenes, B. C. Shen, D. Axen, I. J. Bloodworth, J. C. Clayton, P. Bright-Thomas, Dave Charlton, P. Poffenberger, H. Jeremie, P. G. Estabrooks, A. Jawahery, Marco Cuffiani, M. Settles, Siegfried Bethke, A. K. Honma, B. Nijjhar, J. J. Ward, W. Matthews, W. G. Scott, R. E. Hughes-Jones, Yoram Rozen, F. G. Oakham, P. Vikas, D. Lanske, T. J. McMahon, P. Schütz, Ehud Duchovni, M. A. Thomson, Peter Sherwood, E. L. Barberio, M. Foucher, Alexander Wagner, Paolo Giacomelli, P. M. Watkins, S. L. Chu, R. Bürgin, B. Fabbro, M. Hansroul, E. K. U. Gross, C. Dallapiccola, M. Jimack, A. Gaidot, W. R. Gibson, J. Ludwig, S. Braibant, E. Lefebvre, N. J. Oldershaw, Richard Keeler, K. Runge, P. Bock, J. D. Gillies, T. Wlodek, Junichi Kanzaki, T. Hilse, M. Sproston, D. Karlen, J. Schwiening, R. K. Carnegie, E. do Couto e Silva, N. I. Geddes, S. W. Gensler, F. S. Merrtt, R. D. Heuer, Dezso Horvath, Fabrizio Fabbri, C. Burgard, F. Odorici, O. Runolfsson, M. J. Losty, A. Beck, S. J. Hillier, P. Gagnon, N. Altekamp, J. A. Wilson, A. I. McNab, John Allison, R. Howard, Jean-Arcady Meyer, C. H. Shepherd-Themistocleous, T. Kobayashi, N. L. Rodning, Gideon Bella, R. J. Barlow, D. J. Miller, C. Beeston, Sven Menke, J. Goldberg, B. Poli, A. Sittler, Claudio Grandi, D. R. Rust, J. P. Pansart, R. J. Homer, O. Schaile, R. W. Springer, R. G. Kellogg, Silvia Arcelli, B. Nellen, G. A. Snow, C. P. Ward, S. Söldner-Rembold, H. J. Burckhart, Jacqueline Batley, T. Tsukamoto, N. Tesch, N. K. Watson, H. M. Fischer, M. Starks, A. J. Martin, H. M. Bosch, Lorne Levinson, P. D. Phillips, Gilles Beaudoin, A. Skillman, G. A. Beck, C. Darling, T. J. Smith, Achim Stahl, A. M. Lee, Csaba Hajdu, Stefano Marcellini, E. A. Mckigney, A. Michelini, P. S. Wells, M. Tecchio, E. von Törne, S. W. O'Neale, O. C. Cooke, G. W. Wilson, K. J. Anderson, M. Hauschild, Georges Azuelos, P. Mättig, Stephen Lloyd, E. Tsur, J. Lauber, Terry Richard Wyatt, W. P. Lai, Frank Fiedler, D. Hochman, S. G. Clowes, M. Fierro, Shoji Asai, B. Schmitt, S. A. Robins, Robert M Brown, C. Markus, K. W. Bell, J. E.G. Edwards, C. Hartmann, D. E. Plane, K. Stephens, J. Bechtluft, J. A. McKenna, C. Y. Chang, Misao Sasaki, C. M. Hawkes, Margret Fincke-Keeler, Daniel Lellouch, A. Joly, R. Kowalewski, J. M. Roney, W. Mohr, G. M. Dallavalle, P. Taras, A. Posthaus, J. von Krogh, F. Strumia, Michael Kobel, Takehiko Mori, E. H. Vokurka, K. Ametewee, R. J. Hawkings, V. Gibson, H. G. Evans, Gideon Alexander, Paolo Capiluppi, B. Stockhausen, Paul Kyberd, V. Zacek, F. K. Loebinger, L. A. del Pozo, C. Sbarra, Alan Watson, R. Bartoldus, D. M. Strom, M. J. Goodrick, C. Stegmann, Julie Kirk, H. Fukui, Joleen Pater, I. Cohen, D. L. Rees, D. R. Ward, T. Kress, R. Rylko, H. O. Ogren, Christoph Geich-Gimbel, G. Yekutieli, F. Scharf, R. Giacomelli, German Martinez, Gregor Herten, B. Wilkens, A. D. Schaile, A. A. Carter, Ron Folman, Roger Jones, B. J. King, P. Utzat, M. G. Rison, F. X. Gentit, J. E. Conboy, A. Fürtjes, Gunter Wolf, J. E. Pilcher, S. Wotton, Stefan Kluth, Shlomit Tarem, Tara Shears, U. C. Dunwoody, C. J. Oram, P. A. Hart, M. J. Pearce, U. Müller, Otmar Biebel, C. K. Hargrove, Matthias Schröder, D. L. Wagner, H. Lafoux, H. Deng, J. Letts, Norbert Wermes, Sherry Towers, T. Kawamoto, S. Orito, M. Rosvick, M. Hapke, D. E. Hutchcroft, M. J. Oreglia, J. R. Carter, G. N. Patrick, S. B. Anderson, P. Szymanski, Stan Bentvelsen, Andris Skuja, G. D. Long, Tetsuro Mashimo, W. Gorn, A. S. Turcot, P. Scharff-Hansen, A. M. Smith, G. Vasseur, B. Lorazo, Hans-Christian Schultz-Coulon, James Pinfold, Randall Sobie, Michael Schulz, G. D. Lafferty, D. G. Fong, C. Lewis, J. Gascon, T. W. Pritchard, A. Malik, J. W. Gary, Guenter Duckeck, D. S. Koetke, Marcello Mannelli, G. G. Hanson, G. Giacomelli, P. Schenk, M. S. Dixit, Frans Meijers, J. G. Layter, R. Lahmann, C. Charlesworth, D. C. Imrie, M. Palazzo, Stefania Xella, P. E.L. Clarke, M. K. Jones, G. P. Siroli, J. P. Martin, M. Tscheulin, John Hill, S. De Jong, J. King, H. Przysiezniak, Kiyotomo Kawagoe, P. Weber, R. Van Kooten, and Sachio Komamiya
Subjects: Quark, Physics, Nuclear and High Energy Physics, Particle physics, Meson, Electron–positron annihilation, High Energy Physics::Phenomenology, Bottom quark, Nuclear physics, Fragmentation (mass spectrometry), Mass spectrum, High Energy Physics::Experiment, B meson, Nuclear Experiment, Particle Physics - Experiment, Free parameter
Abstract: A study of b quark fragmentation at LEP is presented using a sample of semileptonic B decays containing a fully reconstructed charm meson. The data are compared to several theoretical models for heavy quark fragmentation; the free parameters in these models are fitted and the sensitivity of the model parameters to the rate of P-wave B meson production is studied. The mean scaled energy fraction of B 0 and B + mesons has been determined to be x E > = 0.695 ± 0.006 ± 0.003 ± 0.007, where the errors are statistical, systematic and model dependence respectively. This result is consistent with previous, less direct measurements from inclusive leptonic B decays. Also presented is a model independent fit to the shape of the energy distribution of weakly decaying B mesons at LEP.
Published: 1995
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40. A comparison of b and uds quark jets to gluon jets

Author: C. M. Hawkes, N. J. Oldershaw, P. Gagnon, Daniel Lellouch, C. Dallapiccola, M. Hapke, E. Lefebvre, Takehiko Mori, John Allison, J. D. Gillies, A. Sittler, A. I. McNab, O. Schaile, R. G. Kellogg, F. Odorici, Csaba Hajdu, Stefano Marcellini, D. E. Hutchcroft, J. Goldberg, V. Zacek, B. Nellen, W. Matthews, H. M. Bosch, N. Altekamp, B. C. Shen, M. Starks, J. Palinkas, B. Stockhausen, Paul Kyberd, F. K. Loebinger, J. Lauber, A. Joly, R. J. Barlow, Siegfried Bethke, M. A. Thomson, M. J. Oreglia, P. Poffenberger, Joleen Pater, A. K. Honma, B. Nijjhar, W. G. Scott, R. Giacomelli, D. J. Miller, Silvia Arcelli, H. G. Evans, M. J. Goodrick, F. Strumia, K. Stephens, R. Kowalewski, Shlomo Dado, Gregor Herten, I. Cohen, P. Schütz, T. Wlodek, J. R. Carter, M. Sproston, I. J. Bloodworth, R. Howard, B. Wilkens, A. Gaidot, U. Müller, J. Bechtluft, G. N. Patrick, Gunter Wolf, F. X. Gentit, P. Igo-Kemenes, M. Settles, H. Jeremie, M. F. Turner-Watson, M. Morii, Dezso Horvath, M. J. Losty, J. P. Pansart, S. G. Clowes, Yoram Rozen, J. E. Pilcher, H. Mes, I. P. Duerdoth, Peter R Hobson, T. Tsukamoto, M. Foucher, Otmar Biebel, N. Tesch, R. E. Hughes-Jones, M. Fierro, V. Gibson, N. I. Geddes, A. J. Martin, Jean-Arcady Meyer, T. Kobayashi, J. E.G. Edwards, D. L. Wagner, F. S. Merritt, D. Rigby, R. J. Hemingway, P. Fath, Junichi Kanzaki, S. Wotton, R. D. Heuer, P. Routenburg, D. Karlen, C. Burgard, Fabrizio Fabbri, T. Behnke, N. L. Rodning, C. Y. Chang, Sachio Komamiya, Theodoros Geralis, B. W. Kennedy, E. A. Mckigney, W. R. Gibson, P. W. Jeffreys, J. Steuerer, G. W. Wilson, D. Axen, A. Jawahery, M. Hauschild, H. Deng, P. Jovanovic, E. do Couto e Silva, E. Ros, A. T. Watson, P. Taras, Michael Kobel, Austin Ball, Eilam Gross, N. K. Watson, B. Poli, C. Darling, Peter Sherwood, W. P. Lai, J. G. Layter, Giora Mikenberg, Dave Charlton, G. A. Beck, C. Markus, Achim Stahl, T. J. Smith, C. K. Hargrove, Peter Krieger, R. Van Kooten, Matthias Schröder, J. Letts, Stefan Kluth, Shlomit Tarem, D. R. Ward, Alexander Wagner, H. Lafoux, T. Kress, R. W. Springer, R. Lahmann, P. Mättig, Shoji Asai, D. C. Imrie, M. Palazzo, J. Ludwig, Julie Kirk, T. P. Kokott, A. Luig, E. H. Vokurka, A. Beck, Sven Menke, J. M. Roney, Norbert Wermes, Sherry Towers, T. Kawamoto, Manuella Vincter, Alessandro Montanari, J. C. Clayton, U. Jost, P. Bright-Thomas, B. Schmitt, P. S. Wells, R. Mir, S. M. Gascon-Shotkin, R. Bürgin, B. Fabbro, C. J. Oram, S. Braibant, J. A. McKenna, Margret Fincke-Keeler, C. Charlesworth, Georges Azuelos, J. J. Ward, P. Vikas, Terry Richard Wyatt, Lorne Levinson, P. D. Phillips, Hans-Christian Schultz-Coulon, E. Tsur, G. P. Siroli, J. King, Marco Cuffiani, D. Lanske, Gilles Beaudoin, S. L. Chu, G. Giacomelli, S. Orito, M. Rosvick, F. Wäckerle, D. M. Gingrich, K. W. Bell, S. W. O'Neale, A. Skillman, K. J. Anderson, Randall Sobie, Gideon Bella, Madjid Boutemeur, Tara Shears, U. C. Dunwoody, P. A. Hart, Stefania Xella, J. C. Hill, R. Bartoldus, Michael Schulz, G. D. Lafferty, H. J. Burckhart, Jacqueline Batley, K. Runge, Misao Sasaki, M. J. Pearce, C. Hartmann, D. E. Plane, H. O. Ogren, Christoph Geich-Gimbel, Kiyotomo Kawagoe, W. Mohr, A. M. Rossi, G. A. Snow, C. P. Ward, P. G. Estabrooks, R. K. Keeler, P. Berlich, P. Bock, F. G. Oakham, G. M. Dallavalle, P. E.L. Clarke, T. Hilse, O. Runolfsson, M. K. Jones, E. L. Barberio, S. Söldner-Rembold, H. M. Fischer, A. Posthaus, D. R. Rust, J. P. Martin, P. Weber, A. Michelini, D. M. Strom, T. W. Pritchard, P. M. Watkins, M. Tscheulin, J. E. Conboy, C. Stegmann, A. Fürtjes, S. De Jong, Paolo Giacomelli, Reda Tafirout, M. Hansroul, S. A. Robins, Guenter Duckeck, H. Fukui, C. Beeston, A. M. Lee, Claudio Grandi, R. Rylko, M. Tecchio, E. von Törne, C. H. Shepherd-Themistocleous, H. Przysiezniak, R. J. Homer, S. B. Anderson, P. Szymanski, Frank Fiedler, D. Hochman, D. L. Rees, F. Scharf, German Martinez, G. G. Hanson, Stan Bentvelsen, A. D. Schaile, P. Schenk, M. S. Dixit, Frans Meijers, A. S. Turcot, K. Ametewee, Gideon Alexander, Paolo Capiluppi, Ehud Duchovni, M. Jimack, S. W. Gensler, S. J. Hillier, Stephen Lloyd, Robert M Brown, P. Scharff-Hansen, A. M. Smith, G. Vasseur, B. Lorazo, James Pinfold, D. G. Fong, C. Lewis, J. Gascon, A. Malik, J. W. Gary, D. S. Koetke, Marcello Mannelli, Andris Skuja, G. D. Long, Tetsuro Mashimo, W. Gorn, O. C. Cooke, J. von Krogh, R. J. Hawkings, L. A. del Pozo, C. Sbarra, G. Yekutieli, A. A. Carter, Ron Folman, Roger Jones, B. J. King, P. Utzat, M. G. Rison, T. J. McMahon, J. Schwiening, R. K. Carnegie, and J. A. Wilson
Subjects: Physics, Quark, Particle physics, Physics and Astronomy (miscellaneous), High Energy Physics::Lattice, Astrophysics::High Energy Astrophysical Phenomena, Electron–positron annihilation, High Energy Physics::Phenomenology, Hadron, Bottom quark, Charged particle, Gluon, Vertex (geometry), Nuclear physics, High Energy Physics::Experiment, Impact parameter, Nuclear Experiment, Particle Physics - Experiment
Abstract: Symmetric three-jet events are selected from hadronic Z0 decays such that the two lower energy jets are each produced at an angle of about 150° with respect to the highest energy jet. In some cases, a displaced secondary vertex is reconstructed in one of the two lower energy jets, which permits the other lower energy jet to be identified as a gluon jet through anti-tagging. In other cases, the highest energy jet is tagged as a b jet or as a light quark (uds) jet using secondary vertex or track impact parameter and momentum information. Comparing the two lower energy jets of the events with a tag in the highest energy jet to the anti-tagged gluon jets yields a direct comparison of b, uds and gluon jets, which are produced with the same energy of about 24 GeV and under the same conditions. We observe b jets and gluon jets to have similar properties as measured by the angular distribution of particle energy around the jet directions and by the fragmentation functions. In contrast, gluon jets are found to be significantly broader and to have a markedly softer fragmentation function than uds jets. For thek ⊥ jet finder withy cut=0.02, we find $$\begin{gathered} \frac{{\left\langle {n^{ch.} } \right\rangle gluon}}{{\left\langle {n^{ch.} } \right\rangle b quark}} = 1.089 \pm 0.024(stat.) \pm 0.024(syst.) \hfill \\ \frac{{\left\langle {n^{ch.} } \right\rangle gluon}}{{\left\langle {n^{ch.} } \right\rangle uds quark}} = 1.390 \pm 0.038(stat.) \pm 0.032(syst.) \hfill \\ \end{gathered} $$ as the ratios of the mean charged particle multiplicity in the gluon jets compared to the b and uds jets. Results are also reported using the cone jet finder.
Published: 1995
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41. A measurement of the forward-backward asymmetry of e+e−→bb by applying a jet charge algorithm to lifetime tagged events

Author: H. O. Ogren, F. S. Merritt, Christoph Geich-Gimbel, J. A. McKenna, Silvia Arcelli, F. X. Gentit, J. E. Conboy, A. Fürtjes, Andris Skuja, M. Fanti, Tara Shears, Margret Fincke-Keeler, N. J. Oldershaw, John Allison, Sachio Komamiya, M. Hapke, G. D. Long, U. C. Dunwoody, P. A. Hart, Theodoros Geralis, E. Ros, A. T. Watson, C. M. Hawkes, Daniel Lellouch, S. Braibant, D. E. Hutchcroft, P. E.L. Clarke, M. K. Jones, Takehiko Mori, P. S. Wells, Tetsuro Mashimo, T. Hilse, H. M. Fischer, T. J. Smith, Terry Richard Wyatt, E. A. Mckigney, W. P. Lai, P. Igo-Kemenes, W. Matthews, H. Mes, I. P. Duerdoth, R.J. Akers, O. Schaile, J. P. Martin, R. G. Kellogg, J. Steuerer, M. J. Pearce, Gideon Bella, O. Runolfsson, P. Fath, R. D. Heuer, K. Stephens, J. M. Roney, Fabrizio Fabbri, H. Jeremie, M. J. Oreglia, Eilam Gross, M. Tscheulin, S. De Jong, A. Michelini, T. Behnke, Stefano Marcellini, R. E. Hughes-Jones, G. A. Snow, C. P. Ward, V. Zacek, T. J. McMahon, M. Starks, J. Schwiening, M. A. Thomson, Stefan Kluth, Shlomit Tarem, C. Beeston, T. P. Kokott, A. Luig, D. Rigby, R. J. Hemingway, H. J. Burckhart, Claudio Grandi, Madjid Boutemeur, A. Buijs, D. R. Rust, A. J. Martin, S. Söldner-Rembold, W. Gorn, R. K. Carnegie, S. W. O'Neale, R. W. Springer, D. M. Strom, C. Stegmann, Jacqueline Batley, A. Gaidot, P. W. Jeffreys, G. A. Beck, Achim Stahl, A. S. Turcot, C. J. Oram, T. Wlodek, P. G. Estabrooks, M. Sproston, K. J. Anderson, R. K. Keeler, H. Fukui, B. Stockhausen, Paul Kyberd, F. K. Loebinger, W. R. Gibson, B. W. Kennedy, A. M. Lee, E. do Couto e Silva, D. Axen, I. J. Bloodworth, A. Jawahery, P. Jovanovic, E. von Törne, P. Bright-Thomas, P. M. Watkins, Austin Ball, Gunter Wolf, J. R. Carter, G. N. Patrick, J. A. Wilson, Peter Sherwood, H. Przysiezniak, S. A. Robins, Peter Krieger, Gregor Herten, V. Gibson, Otmar Biebel, C. Y. Chang, J. J. Ward, M. Settles, P. Scharff-Hansen, Alexander Wagner, T. Tsukamoto, P. Vikas, R. Giacomelli, Sven Menke, D. Lanske, D. L. Wagner, B. Schmitt, N. Tesch, B. Wilkens, Shlomo Dado, J. Ludwig, Yoram Rozen, S. Wotton, Manuella Vincter, K. Runge, P. Bock, Marco Cuffiani, E. Lefebvre, R. Van Kooten, Kiyotomo Kawagoe, Alessandro Montanari, P. Taras, Michael Kobel, J. Bechtluft, M. Foucher, U. Müller, H. Deng, M. F. Turner-Watson, N. K. Watson, F. Odorici, R. Mir, P. Gagnon, Xinchou Lou, M. Morii, J. E. Pilcher, R. Howard, A. Beck, A. I. McNab, J. Goldberg, Peter R Hobson, Georges Azuelos, P. Weber, F. Wäckerle, J. P. Pansart, A. M. Smith, C. Sbarra, Julie Kirk, Giora Mikenberg, P. Routenburg, B. Nellen, D. M. Gingrich, Junichi Kanzaki, D. Karlen, J. Lauber, S. G. Clowes, M. Fierro, J. E.G. Edwards, J. Letts, D. R. Ward, T. Kress, H. Lafoux, G. W. Wilson, S. L. Chu, M. Hauschild, C. Burgard, G. T. Zorn, G. Vasseur, B. Lorazo, Paolo Giacomelli, A. Joly, Norbert Wermes, Sherry Towers, T. Kawamoto, C. Markus, P. Berlich, W. Mohr, R. Lahmann, M. Hansroul, G. Yekutieli, H. M. Bosch, Wolfram Dietrich Zeuner, F. G. Oakham, P. Poffenberger, K. W. Bell, H. G. Evans, A. Posthaus, Dave Charlton, D. C. Imrie, M. J. Goodrick, I. Cohen, S. Orito, James Pinfold, M. Rosvick, E. L. Barberio, D. G. Fong, J. Gascon, A. A. Carter, Ron Folman, C. Darling, J. C. Hill, N. I. Geddes, Misao Sasaki, C. H. Shepherd-Themistocleous, R. Bürgin, G. G. Hanson, M. W. Redmond, G. P. Siroli, J. King, C. Dallapiccola, Roger Jones, P. Schütz, P. Texeira-Dias, B. Fabbro, Lorne Levinson, P. D. Phillips, J. D. Gillies, B. J. King, R. J. Homer, P. Mättig, B. C. Shen, N. L. Rodning, Frank Fiedler, G. Giacomelli, B. Poli, Shoji Asai, P. Utzat, N. Altekamp, D. Hochman, C. K. Hargrove, Siegfried Bethke, A. K. Honma, B. Nijjhar, M. G. Rison, W. G. Scott, R. J. Barlow, D. L. Rees, D. J. Miller, J. C. Clayton, Matthias Schröder, P. Schenk, Gilles Beaudoin, A. Skillman, F. Scharf, M. S. Dixit, M. J. Losty, Frans Meijers, A. M. Rossi, J. G. Layter, Hans-Christian Schultz-Coulon, A. D. Schaile, C. Hartmann, D. E. Plane, C. Charlesworth, G. M. Dallavalle, Randall Sobie, Michael Schulz, G. D. Lafferty, Reda Tafirout, T. W. Pritchard, Guenter Duckeck, S. B. Anderson, P. Szymanski, Stan Bentvelsen, R. Kowalewski, K. Ametewee, Gideon Alexander, Paolo Capiluppi, Stephen Lloyd, M. Tecchio, Robert M Brown, A. Malik, J. W. Gary, D. S. Koetke, Ehud Duchovni, Marcello Mannelli, J. E. Duboscq, M. Jimack, F. Palmonari, S. W. Gensler, S. J. Hillier, T. Kobayashi, O. C. Cooke, J. von Krogh, R. J. Hawkings, L. A. del Pozo, and R. Bartoldus
Subjects: Physics, Quark, Particle physics, Physics and Astronomy (miscellaneous), media_common.quotation_subject, Charge (physics), Jet (particle physics), Asymmetry, Standard Model, Nuclear physics, Higgs boson, Engineering (miscellaneous), Algorithm, Energy (signal processing), media_common, Bar (unit)
Abstract: The forward-backward asymmetry of$e^ + e^ - \to Z^0 \to b\bar b$ has been measured using approximately 2.15 million hadronicZ0 decays collected at the LEP e+e− collider with the OPAL detector. A lifetime tag technique was used to select an enriched$b\bar b$ event sample. The measurement of the$b\bar b$ asymmetry was then performed using a jet charge algorithm to determine the direction of the primary quark. Values of: $$\begin{gathered} A_{FB}^b = 0.062 \pm 0.034 \pm 0.002 - 0.082\Delta (\Gamma _{b\bar b} /\Gamma _{had} ) \hfill \\ at\sqrt s = 89.52GeV, \hfill \\ A_{FB}^b = 0.0963 \pm 0.0067 \pm 0.0038 - 0.471\Delta (\Gamma _{b\bar b} /\Gamma _{had} ) \hfill \\ at\sqrt s = 91.25GeV, \hfill \\ A_{FB}^b = 0.172 \pm 0.028 \pm 0.007 - 0.055\Delta (\Gamma _{b\bar b} /\Gamma _{had} ) \hfill \\ at\sqrt s = 92.94GeV, \hfill \\ \end{gathered}$$ were measured where, in each case, the first error is statistical, the second is systematic and the third term gives the variation due to a change$\Delta (\Gamma _{b\bar b} /\Gamma _{had} )$ in the value of$\Gamma _{b\bar b} /\Gamma _{had} = 0.216$ assumed. The dependence on the assumed charm asymmetry at the same energy is Δ(AFBb)≈+0.07Δ(AFBc). Assuming the Standard Model form for the couplings, these measurements correspond to an effective weak mixing angle of: $$\sin ^2 \theta _W^{eff,e} = 0.2313 \pm 0.0012 \pm 0.0006$$ giving Mtop=196−38−19+33+16GeV/c2, where the first error is statistical and the second is systematic. The Higgs mass assumed is 300 GeV/c2. A variation in the assumed mass of the Higgs boson between 60 and 1000 GeV/c2 corresponds to an uncertainty in sin2θWeff,e of ±0.00006 and on Mtop of−26+20GeV/c2.
Published: 1995
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42. Δ++ production in hadronic Z0 decays

Author: W. R. Gibson, H. J. Burckhart, Jacqueline Batley, S. Braibant, A. Beck, U. Jost, R. Mir, Andris Skuja, G. D. Long, A. I. McNab, J. Goldberg, D. Rigby, R. J. Hemingway, R. M. Brown, Lorne Levinson, P. D. Phillips, B. W. Kennedy, G. W. Wilson, P. Jovanovic, M. Hauschild, Austin Ball, C. Markus, Peter Krieger, Paolo Giacomelli, M. Hansroul, Manuella Vincter, Alessandro Montanari, Gilles Beaudoin, F. G. Oakham, Tetsuro Mashimo, B. Nellen, D. Axen, A. Jawahery, E. H. Vokurka, A. Skillman, E. L. Barberio, N. I. Geddes, B. Stockhausen, Paul Kyberd, F. K. Loebinger, C. H. Shepherd-Themistocleous, R. Lahmann, D. C. Imrie, M. Palazzo, Peter Sherwood, C. Dallapiccola, F. S. Merritt, C. Hartmann, D. E. Plane, J. D. Gillies, N. L. Rodning, R. J. Homer, N. Altekamp, W. Gorn, N. J. Oldershaw, U. Müller, G. P. Siroli, J. King, R. J. Barlow, H. G. Evans, M. J. Goodrick, Silvia Arcelli, D. J. Miller, Joleen Pater, G. M. Dallavalle, Stephen Lloyd, B. Poli, J. Ludwig, G. A. Snow, C. P. Ward, K. Runge, P. Bock, W. Matthews, P. Igo-Kemenes, H. Mes, I. Cohen, I. P. Duerdoth, R. Giacomelli, C. Darling, O. Schaile, H. Jeremie, J. Lauber, M. A. Thomson, J. Bechtluft, Dave Charlton, P. Fath, Margret Fincke-Keeler, J. A. McKenna, R. Kowalewski, S. B. Anderson, P. Szymanski, R. E. Hughes-Jones, Frank Fiedler, D. Hochman, S. Söldner-Rembold, R. Van Kooten, P. S. Wells, P. Scharff-Hansen, S. M. Gascon-Shotkin, Kiyotomo Kawagoe, T. J. McMahon, G. G. Hanson, E. K. U. Gross, F. Strumia, T. J. Smith, K. Stephens, A. Gaidot, P. Mättig, K. Ametewee, Shoji Asai, T. Wlodek, J. Schwiening, M. Sproston, Terry Richard Wyatt, Gideon Alexander, Stefan Kluth, R. Bürgin, B. Fabbro, Paolo Capiluppi, M. Starks, A. J. Martin, Reda Tafirout, R. Bartoldus, R. K. Carnegie, E. A. Mckigney, Shlomit Tarem, C. M. Hawkes, C. K. Hargrove, Daniel Lellouch, P. Weber, A. M. Smith, T. Tsukamoto, N. Tesch, Takehiko Mori, H. O. Ogren, V. Gibson, Christoph Geich-Gimbel, Matthias Schröder, G. Giacomelli, Stan Bentvelsen, E. do Couto e Silva, A. Joly, C. J. Oram, J. A. Wilson, G. Vasseur, P. Schenk, B. Lorazo, Ehud Duchovni, S. L. Chu, V. Zacek, N. K. Watson, F. Wäckerle, A. M. Rossi, M. Jimack, P. Gagnon, D. R. Ward, T. Kress, D. M. Gingrich, Sven Menke, W. P. Lai, H. Lafoux, J. C. Clayton, H. M. Fischer, John Allison, J. Palinkas, S. W. Gensler, A. S. Turcot, F. X. Gentit, S. J. Hillier, T. Kobayashi, P. Berlich, M. S. Dixit, Gregor Herten, Frans Meijers, A. Sittler, J. E. Conboy, A. Fürtjes, James Pinfold, Gunter Wolf, D. G. Fong, C. Lewis, J. Gascon, Shlomo Dado, E. Lefebvre, A. Michelini, R. Howard, P. E.L. Clarke, W. Mohr, B. Wilkens, D. R. Rust, J. P. Pansart, A. Wagne, G. A. Beck, Achim Stahl, R. G. Kellogg, H. M. Bosch, A. Posthaus, I. J. Bloodworth, O. C. Cooke, Csaba Hajdu, S. A. Robins, M. K. Jones, J. P. Martin, F. Odorici, Stefano Marcellini, A. M. Lee, M. Tscheulin, J. E. Pilcher, J. M. Roney, M. Tecchio, E. von Törne, A. Malik, S. De Jong, J. W. Gary, D. S. Koetke, B. Schmitt, D. M. Strom, Hans-Christian Schultz-Coulon, C. Stegmann, Tara Shears, J. von Krogh, Giora Mikenberg, H. Fukui, M. Settles, Randall Sobie, Michael Schulz, G. D. Lafferty, R. Rylko, Yoram Rozen, U. C. Dunwoody, P. A. Hart, D. L. Rees, Marcello Mannelli, T. W. Pritchard, S. Wotton, M. J. Pearce, Guenter Duckeck, F. Scharf, German Martinez, R. J. Hawkings, R. D. Heuer, Fabrizio Fabbri, M. Foucher, A. D. Schaile, H. Przysiezniak, T. Behnke, J. Steuerer, L. A. del Pozo, C. Sbarra, Madjid Boutemeur, Junichi Kanzaki, D. Karlen, C. Burgard, G. Yekutieli, J. G. Layter, Marco Cuffiani, A. A. Carter, Ron Folman, C. Charlesworth, Roger Jones, P. G. Estabrooks, R. K. Keeler, B. J. King, P. Utzat, Stefania Xella, M. G. Rison, P. M. Watkins, Otmar Biebel, D. L. Wagner, H. Deng, J. Letts, Norbert Wermes, Sherry Towers, T. Kawamoto, R. W. Springer, Georges Azuelos, E. Tsur, S. Orito, M. Rosvick, K. W. Bell, J. C. Hill, Misao Sasaki, M. Hapke, B. C. Shen, Siegfried Bethke, A. K. Honma, B. Nijjhar, D. E. Hutchcroft, W. G. Scott, M. J. Oreglia, J. R. Carter, Dezso Horvath, G. N. Patrick, M. J. Losty, Jean-Arcady Meyer, P. Poffenberger, P. Schütz, S. G. Clowes, M. Fierro, J. E.G. Edwards, C. Y. Chang, P. W. Jeffreys, P. Taras, Michael Kobel, P. Bright-Thomas, J. J. Ward, P. Vikas, D. Lanske, Julie Kirk, T. Hilse, O. Runolfsson, C. Beeston, Claudio Grandi, S. W. O'Neale, K. J. Anderson, Sachio Komamiya, Theodoros Geralis, E. Ros, A. T. Watson, T. P. Kokott, A. Luig, M. F. Turner-Watson, M. Morii, Peter R Hobson, P. Routenburg, and Gideon Bella
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Electron–positron annihilation, Nuclear Theory, High Energy Physics::Phenomenology, Monte Carlo method, Hadron, Astrophysics::Cosmology and Extragalactic Astrophysics, Strangeness, Nuclear physics, Baryon, Fragmentation function, High Energy Physics::Experiment, Nuclear Experiment, Production rate
Abstract: The production of Δ++ baryons has been measured using 3.5 million hadronic Z0 decays collected with the OPAL detector at LEP. The production rate and fragmentation function are presented. A total of 0.22 ± 0.04 ± 0.04 Δ ++ + ( Δ ) −− per hadronic Z0 decay is observed. The fragmentation function is found to be softer than that predicted by the JETSET and HERWIG Monte Carlo event generators. With this measurement of Δ++ production, at least one baryon of each strangeness level in the lightest baryon decuplet has now been measured at LEP.
Published: 1995
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43. Measurement of the multiplicity of charm quark pairs from gluons in hadronic Z0 Decays

Author: Sachio Komamiya, T. Hilse, John Allison, O. Runolfsson, Theodoros Geralis, E. Ros, D. R. Rust, Madjid Boutemeur, C. Beeston, Claudio Grandi, R. W. Springer, T. P. Kokott, A. Luig, A. M. Lee, P. G. Estabrooks, R. G. Kellogg, Gregor Herten, P. W. Jeffreys, E. von Törne, C. M. Hawkes, Stefano Marcellini, Daniel Lellouch, S. Braibant, Takehiko Mori, Tara Shears, P. Bright-Thomas, B. Wilkens, P. M. Watkins, Georges Azuelos, J. Steuerer, J. J. Ward, P. Vikas, C. Sbarra, D. Lanske, S. G. Clowes, M. Fierro, Reda Tafirout, U. C. Dunwoody, V. Zacek, P. A. Hart, Gideon Bella, R. Bartoldus, K. W. Bell, A. Joly, H. J. Burckhart, Jacqueline Batley, Eilam Gross, M. Fanti, J. E. Pilcher, M. J. Pearce, H. O. Ogren, M. W. Redmond, Misao Sasaki, Silvia Arcelli, Christoph Geich-Gimbel, G. Yekutieli, R. Mir, G. A. Snow, C. P. Ward, A. I. McNab, M. Hapke, T. Behnke, I. J. Bloodworth, W. R. Gibson, J. Goldberg, G. W. Wilson, M. Hauschild, G. A. Beck, P. Igo-Kemenes, D. E. Hutchcroft, B. Stockhausen, Paul Kyberd, A. A. Carter, J. Lauber, S. Söldner-Rembold, Richard Keeler, F. K. Loebinger, Achim Stahl, Ron Folman, Roger Jones, P. Teixeira-Dias, B. C. Shen, H. Jeremie, U. Müller, Marco Cuffiani, F. X. Gentit, B. J. King, P. Utzat, M. Settles, Yoram Rozen, M. J. Oreglia, C. Markus, R. E. Hughes-Jones, B. Nellen, P. Gagnon, A. Beck, M. G. Rison, S. L. Chu, M. Foucher, M. F. Turner-Watson, M. Morii, Peter R Hobson, J. G. Layter, B. Schmitt, E. A. Mckigney, F. G. Oakham, W. P. Lai, R. Howard, R. Giacomelli, J. E.C. Edwards, R. D. Heuer, O. C. Cooke, Lorne Levinson, P. D. Phillips, Siegfried Bethke, A. K. Honma, B. Nijjhar, W. G. Scott, J. E. Conboy, A. Fürtjes, J. P. Pansart, E. L. Barberio, N. J. Oldershaw, P. Routenburg, G. T. Zorn, Junichi Kanzaki, E. do Couto e Silva, D. Karlen, C. Burgard, R.J. Akers, C. Charlesworth, M. J. Losty, H. M. Bosch, Wolfram Dietrich Zeuner, Gilles Beaudoin, A. Skillman, C. K. Hargrove, Matthias Schröder, Fabrizio Fabbri, C. Dallapiccola, Shlomo Dado, S. B. Anderson, P. Szymanski, J. von Krogh, H. G. Evans, M. J. Goodrick, J. R. Carter, S. W. O'Neale, G. N. Patrick, I. Cohen, K. J. Anderson, F. S. Merritt, R. Van Kooten, Paolo Giacomelli, M. Hansroul, Dave Charlton, J. M. Roney, O. Schaile, J. D. Gillies, R. J. Hawkings, D. Axen, A. Jawahery, C. Hartmann, Sven Menke, D. E. Plane, Otmar Biebel, Gunter Wolf, A. Buijs, C. Darling, Peter Sherwood, T. J. Smith, M. Starks, A. J. Martin, L. A. del Pozo, D. M. Strom, C. Stegmann, Stan Bentvelsen, C. H. Shepherd-Themistocleous, Alexander Wagner, T. J. McMahon, N. Altekamp, D. L. Wagner, G. M. Dallavalle, J. Bechtluft, J. A. McKenna, J. Ludwig, K. Runge, P. Bock, Giora Mikenberg, R. Bürgin, B. Fabbro, P. Mättig, J. Schwiening, R. J. Homer, R. K. Carnegie, G. G. Hanson, P. Poffenberger, Shoji Asai, H. Fukui, Margret Fincke-Keeler, R. J. Barlow, J. A. Wilson, R. Lahmann, Hans-Christian Schultz-Coulon, F. Wäckerle, D. J. Miller, Randall Sobie, Michael Schulz, G. D. Lafferty, D. C. Imrie, Alan Watson, S. Wotton, D. M. Gingrich, G. Giacomelli, H. Deng, T. W. Pritchard, P. Schütz, Guenter Duckeck, G. P. Siroli, J. King, P. Schenk, P. Berlich, A. S. Turcot, D. Rigby, R. J. Hemingway, M. S. Dixit, Frans Meijers, C. Y. Chang, J. Letts, P. S. Wells, B. W. Kennedy, P. Taras, Norbert Wermes, Michael Kobel, P. Jovanovic, P. E.L. Clarke, M. K. Jones, Terry Richard Wyatt, Sherry Towers, T. Kawamoto, Stefan Kluth, Shlomit Tarem, J. P. Martin, Austin Ball, M. Tscheulin, John Hill, S. De Jong, Julie Kirk, H. Lafoux, S. Orito, M. Rosvick, S. M. Gascon-Shotkin, Peter Krieger, Kiyotomo Kawagoe, H. Przysiezniak, Alessandro Montanari, A. M. Rossi, C. J. Oram, N. I. Geddes, N. L. Rodning, P. Weber, B. Poli, H. M. Fischer, A. Michelini, K. Stephens, S. A. Robins, V. Gibson, D. R. Ward, T. Kress, J. C. Clayton, Frank Fiedler, D. Hochman, R. Kowalewski, James Pinfold, D. G. Fong, J. Gascon, A. Malik, J. W. Gary, D. S. Koetke, Marcello Mannelli, J. E. Duboscq, Andris Skuja, G. D. Long, Tetsuro Mashimo, W. Gorn, P. Scharff-Hansen, A. M. Smith, G. Vasseur, B. Lorazo, K. Ametewee, P. Vincter, Gideon Alexander, Paolo Capiluppi, Stephen Lloyd, M. Tecchio, Robert M Brown, Ehud Duchovni, M. Jimack, F. Palmonari, S. W. Gensler, S. J. Hillier, T. Kobayashi, H. Mes, I. P. Duerdoth, P. Fath, E. Lefebvre, N. K. Watson, F. Odorici, W. Mohr, A. Posthaus, D. L. Rees, F. Scharf, A. D. Schaile, W. Matthews, M. A. Thomson, A. Gaidot, T. Wlodek, M. Sproston, T. Tsukamoto, and N. Tesch
Subjects: Quark, Physics, Nuclear and High Energy Physics, Particle physics, High Energy Physics::Lattice, Electron–positron annihilation, Nuclear Theory, High Energy Physics::Phenomenology, Hadron, Jet (particle physics), Charm quark, Gluon, Nuclear physics, Pair production, High Energy Physics::Experiment, Nuclear Experiment, Particle Physics - Experiment, Lepton
Abstract: We have measured the multiplicity of charm quark pairs arising from gluon splitting in a sample of about 3.5 million hadronic Z0 decays. By selecting a 3-jet event topology and tagging charmed hadrons in the lowest energy jet using leptons, we established a signature of heavy quark pair production from gluons. The average number of gluons splitting into a c c pair per hadronic event was measured to be n g→c c =(2.27±0.28±0.41) × 10 −2 .
Published: 1995
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44. A measurement of the Λ0 lifetime

Author: P. Scharff-Hansen, P. Igo-Kemenes, Richard Keeler, S. L. Chu, H. Jeremie, R. E. Hughes-Jones, A. M. Smith, Sachio Komamiya, Theodoros Geralis, E. Ros, G. Vasseur, B. Lorazo, H. Mes, I. P. Duerdoth, P. Fath, J. P. Martin, D. Rigby, R. J. Hemingway, Christopher Hawkes, E. Lefebvre, James Pilcher, T. Hilse, E. do Couto e Silva, Kiyotomo Kawagoe, R. Howard, F. Odorici, B. W. Kennedy, P. Jovanovic, John Wilson, Austin Ball, T. P. Kokott, Carla Sbarra, A. Luig, D. R. Rust, J. P. Pansart, J. Ludwig, M. Hapke, Peter Krieger, Hans-Christian Schultz-Coulon, O. Runolfsson, Manuella Vincter, Alessandro Montanari, J. R. Batley, Randall Sobie, Michael Schulz, G. D. Lafferty, G. W. Wilson, D. E. Hutchcroft, A. Joly, James Pinfold, G. Yekutieli, P. Weber, D. G. Fong, R. W. Springer, A. M. Lee, Sven Menke, M. Hauschild, Tara Shears, J. Gascon, Takashi Kobayashi, C. Beeston, A. Jawahery, J. Bechtluft, Ron Folman, J. A. McKenna, T. W. Pritchard, Roger Jones, E. von Törne, R. Mir, M. W. Redmond, C. Markus, P. E.L. Clarke, W. G. Scott, U. C. Dunwoody, Claudio Grandi, B. J. King, M. K. Jones, Guenter Duckeck, P. Utzat, P. A. Hart, A. Malik, J. W. Gary, J. Lauber, Shlomo Dado, C. Darling, Peter Sherwood, Terry Richard Wyatt, M. G. Rison, Stefan Kluth, Shlomit Tarem, S. W. O'Neale, J. Steuerer, Eilam Gross, D. S. Koetke, M. F. Turner-Watson, R. Lahmann, Ch. Geich-Gimbel, M. Fanti, D. Axen, M. J. Pearce, M. Tscheulin, John Hill, M. Morii, D. C. Imrie, Georges Azuelos, Marcello Mannelli, J. E. Duboscq, P. W. Jeffreys, Alexander Wagner, R. Bartoldus, J. R. Carter, E. L. Barberio, G. N. Patrick, Andris Skuja, T. J. McMahon, S. De Jong, A. S. Turcot, C. Dallapiccola, Helfried Burckhart, J. Schwiening, Peter R Hobson, R. K. Carnegie, B. Stockhausen, Paul Kyberd, Otmar Biebel, P. Mättig, Shoji Asai, D. L. Wagner, K. W. Bell, K. Runge, P. Bock, Giora Mikenberg, G. P. Siroli, A. I. McNab, J. D. Gillies, A. Buijs, P. Routenburg, Daniel Lellouch, F. G. Oakham, Gregor Herten, J. Goldberg, Misao Sasaki, J. King, G. D. Long, P. Poffenberger, D. M. Strom, C. Stegmann, B. Nellen, Tetsuro Mashimo, M. J. Losty, H. Deng, Takehiko Mori, N. Altekamp, Tatsuo Kawamoto, H. Fukui, B. C. Shen, S. Braibant, R. J. Barlow, D. J. Miller, B. Wilkens, Harold Ogren, Matthias Schröder, P. Bright-Thomas, R. D. Heuer, Siegfried Bethke, H. Przysiezniak, Marco Cuffiani, Douglas Gingrich, V. Zacek, Fabrizio Fabbri, P. Gagnon, A. K. Honma, B. Nijjhar, J. Letts, F. X. Gentit, J. E. Conboy, R. Van Kooten, A. Fürtjes, J. J. Ward, O. C. Cooke, P. Vikas, M. J. Goodrick, I. Cohen, P. Schütz, Sherry Towers, I. J. Bloodworth, W. Gorn, P. S. Wells, D. Lanske, G. A. Snow, S. B. Anderson, Norbert Wermes, S. Söldner-Rembold, P. Szymanski, N. J. Oldershaw, W. Mohr, R. Giacomelli, Gunter Wolf, S. Orito, M. Settles, Yoram Rozen, C. Y. Chang, M. Foucher, J. G. Layter, Dave Charlton, M. Rosvick, A. A. Carter, R.J. Akers, F. Wäckerle, G. T. Zorn, J. von Krogh, Junichi Kanzaki, P. Taras, Stan Bentvelsen, D. Karlen, R. Bürgin, B. Fabbro, C. Burgard, P. Berlich, R. J. Hawkings, O. Schaile, C. Charlesworth, Michael Kobel, U. Müller, Kelby Anderson, G. Giacomelli, H. M. Bosch, Wolfram Dietrich Zeuner, L. A. del Pozo, Gideon Bella, Julie Kirk, H. Lafoux, S. Wotton, M. Starks, Frank Merritt, A. J. Martin, S. G. Clowes, M. Fierro, J. E.G. Edwards, C. K. Hargrove, G. G. Hanson, John Allison, Xinchou Lou, P. Schenk, M. S. Dixit, Frans Meijers, T. Behnke, R. G. Kellogg, Stefano Marcellini, Peter Watkins, Fred Loebinger, Stephen Lloyd, M. Tecchio, Robert M Brown, R. Kowalewski, K. Ametewee, Gideon Alexander, Paolo Capiluppi, Ehud Duchovni, J. C. Clayton, M. Jimack, T. J. Smith, K. Stephens, W. Matthews, Mark Oreglia, M. A. Thomson, F. Palmonari, V. Gibson, S. W. Gensler, A. Gaidot, T. Wlodek, M. Sproston, D. R. Ward, T. Kress, Christopher P. Ward, Frank Fiedler, D. Hochman, Hal Evans, T. Tsukamoto, N. Tesch, N. K. Watson, G. A. Beck, Achim Stahl, P. Teixeira-Dias, B. Schmitt, A. Posthaus, Margret Fincke-Keeler, D. L. Rees, Paolo Giacomelli, M. Hansroul, F. Scharf, C. H. Shepherd-Themistocleous, R. J. Homer, A. D. Schaile, Madjid Boutemeur, P. G. Estabrooks, H. M. Fischer, A. Michelini, S. A. Robins, Silvia Arcelli, C. J. Oram, N. I. Geddes, E. A. Mckigney, W. P. Lai, N. L. Rodning, B. Poli, J. M. Roney, A. M. Rossi, W. R. Gibson, A. Beck, Lorne Levinson, P. D. Phillips, Gilles Beaudoin, A. Skillman, C. Hartmann, D. E. Plane, Stephen Hillier, G. M. Dallavalle, Alan Watson, and Reda Tafirout
Subjects: Baryon, Nuclear physics, Physics, Nuclear and High Energy Physics, Electron–positron annihilation, Hadron, Atomic physics
Abstract: The lifetime of the Λ b 0 baryon has been measured using 3.6 million hadronic Z 0 decays recorded by the OPAL detector at LEP from 1990 to 1994. A sample of Λ b 0 decays is obtained using partially reconstructed semileptonic decays involving Λ c + l − combinations, where the Λ c + is reconstructed from its decay to a pK − π + final state. From the 69 ± 13 Λ c + l − combinations attributed to Λ b 0 decays in this data sample, we measure τ ( Λ b 0 ) = 1.14 −0.19 +0.22 ± 0.07 ps, where the errors are statistical and systematic, respectively.
Published: 1995
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45. The retention of particles intercepted by a dense aggregation of lake-outlet suspension feeders

Author: Roger S. Wotton, Kevin Ashelford, and Björn Malmqvist
Subjects: Reino unido, Ecology, Environmental chemistry, parasitic diseases, Suspended particles, Seston, Simulium noelleri, Aquatic Science, Biology, Eutrophication, Royaume uni
Abstract: A thin film of water flowed vertically over the wooden planks impounding a eutrophic lake in Kent, United Kingdom. Suspension-feeding larvae of the blackfly Simulium noelleri Friederichs formed a carpet-like, dense aggregation over these planks and fed on the suspended particles (seston) carried from the lake. Yellow, fluorescent dye particles were used to model the abundant seston and to produce easily-identifiable bands across the gut contents of larvae. No bands were found in larvae that had been feeding for 3 h after the initial application, so egestion of the bands will have been complete by this time. Nevertheless, dye particles were found in the gut contents of larvae after 3 h and 6 h of feeding on natural seston, though quantities were small (approximately 8% of the initial concentration after 3 h and 2% after 6 h). Retention of particles at this site was thus surprisingly low.
Published: 1995
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46. A measurement of charged particle multiplicity in Z0 → cc̄ and Z0 → bb̄ events

Author: Gideon Bella, H. J. Burckhart, Jacqueline Batley, A. Buijs, D. M. Strom, Margret Fincke-Keeler, C. Stegmann, F. S. Merritt, M. Fanti, P. Igo-Kemenes, H. Fukui, H. Jeremie, R. E. Hughes-Jones, U. Maur, Xinchou Lou, W. Matthews, Reda Tafirout, J. A. McKenna, H. M. Fischer, E. do Couto e Silva, M. A. Thomson, M. W. Redmond, S. Braibant, A. Michelini, M. F. Turner-Watson, M. Morii, Peter R Hobson, P. Routenburg, Gregor Herten, E. K. U. Gross, A. Gaidot, T. Wlodek, Silvia Arcelli, M. Sproston, Dave Charlton, B. Wilkens, D. E. Plane, G. A. Snow, C. P. Ward, D. L. Rees, M. J. Oreglia, R. Bartoldus, A. Yeaman, G. M. Dallavalle, R. Bürgin, B. Fabbro, Sachio Komamiya, Theodoros Geralis, E. Ros, A. T. Watson, R. D. Heuer, Fabrizio Fabbri, S. A. Robins, E. Lefebvre, H. O. Ogren, Christoph Geich-Gimbel, N. Tesch, S. Söldner-Rembold, T. P. Kokott, John Allison, A. Luig, R. W. Springer, P. S. Wells, Matthias Schröder, J. E. Pilcher, T. J. Smith, K. Stephens, C. Y. Chang, Terry Richard Wyatt, Tohru Takeshita, N. K. Watson, R. Van Kooten, F. Odorici, Erez Etzion, J. R. Carter, G. N. Patrick, N. J. Oldershaw, R. G. Kellogg, W. R. Gibson, R.J. Akers, R. Mir, Otmar Biebel, T. Hilse, Georges Azuelos, Stefan Kluth, F. X. Gentit, Barry King, D. L. Wagner, J. E. Conboy, A. Fürtjes, A. Beck, Shlomit Tarem, Shlomo Dado, Stefano Marcellini, T. G. Shears, E. Heflin, K. W. Bell, P. Taras, R. M. Brown, Lorne Levinson, H. Deng, I. J. Bloodworth, O. Schaile, O. Runolfsson, P. Gagnon, W. Mohr, P. D. Phillips, C. J. Oram, J. C. Hill, Gilles Beaudoin, W. P. Lai, Michael Kobel, Misao Sasaki, D. M. Gingrich, A. Skillman, J. Lauber, V. Gibson, B. C. Shen, B. Stockhausen, Paul Kyberd, M. Starks, F. K. Loebinger, A. M. Rossi, R. P. Middleton, A. I. McNab, Giora Mikenberg, Ehud Duchovni, T. Tsukamoto, P. Berlich, R. Howard, Siegfried Bethke, A. K. Honma, B. Nijjhar, J. Letts, Claude Leroy, J. Goldberg, W. G. Scott, H. Takeda, J. P. Pansart, P. A. Elcombe, Paolo Giacomelli, J. M. Roney, M. Settles, Norbert Wermes, Sherry Towers, C. Beeston, T. Kawamoto, M. Hansroul, B. Nellen, R. Giacomelli, D. R. Rust, F. G. Oakham, Claudio Grandi, Julie Kirk, M. Jimack, H. Lafoux, P. Leblanc, Yoram Rozen, G. W. Wilson, G. T. Zorn, M. Hauschild, S. Orito, M. Yurko, M. Rosvick, N. I. Geddes, M. J. Losty, E. L. Barberio, D. R. Ward, T. Kress, H. Mes, Madjid Boutemeur, I. P. Duerdoth, C. H. Shepherd-Themistocleous, C. Markus, P. W. Jeffreys, M. Foucher, A. M. Lee, P. Fath, N. L. Rodning, R. J. Homer, H. G. Evans, F. Scharf, F. Palmonari, B. Poli, M. J. Goodrick, P. A. Hart, I. Cohen, A. D. Schaile, P. G. Estabrooks, R. K. Keeler, D. Rigby, R. J. Hemingway, H. M. Bosch, Wolfram Dietrich Zeuner, M. J. Pearce, S. W. Gensler, G. A. Beck, Gunter Wolf, P. Bright-Thomas, Junichi Kanzaki, Achim Stahl, P. Teixeira-Dias, S. J. Hillier, B. W. Kennedy, D. Karlen, P. M. Watkins, C. Burgard, P. Poffenberger, P. Jovanovic, J. J. Ward, Austin Ball, P. Vikas, B. Schmitt, S. Wotton, D. Hochman, Peter Krieger, Peter Fischer, Manuella Vincter, Alessandro Montanari, U. Müller, P. Schütz, A. Posthaus, C. Dallapiccola, A. J. Martin, J. D. Gillies, R. J. Barlow, S. G. Clowes, D. J. Miller, M. Fierro, J. E.G. Edwards, C. Darling, C. K. Hargrove, O. Tousignant, P. Mättig, Shoji Asai, S. W. O'Neale, K. J. Anderson, C. M. Hawkes, Daniel Lellouch, T. Behnke, Takehiko Mori, Stephen Lloyd, M. Tecchio, V. Zacek, R. Kowalewski, Taizo Kobayashi, K. Ametewee, Gideon Alexander, Paolo Capiluppi, D. Axen, A. Jawahery, Peter Sherwood, Alexander Wagner, J. Hagemann, J. Ludwig, K. Runge, P. Bock, O. C. Cooke, P. Scharff-Hansen, Hans-Christian Schultz-Coulon, J. G. Layter, Randall Sobie, Michael Schulz, G. D. Lafferty, T. W. Pritchard, C. Charlesworth, N. Capdevielle, Guenter Duckeck, J. von Krogh, A. M. Smith, Dave Robinson, A. S. Turcot, G. Vasseur, B. Lorazo, R. Lahmann, D. C. Imrie, V. H. Winterer, L. A. del Pozo, James Pinfold, C. Sbarra, D. G. Fong, J. Gascon, G. P. Siroli, J. King, P. Szymanski, Michael Dittmar, Christoph Schwick, G. Yekutieli, J. W. Gary, D. S. Koetke, A. A. Carter, Marcello Mannelli, J. E. Duboscq, Ron Folman, Roger Jones, Andris Skuja, C. Jui, G. D. Long, Stan Bentvelsen, Tetsuro Mashimo, P. Utzat, W. Gorn, M. G. Rison, Kiyotomo Kawagoe, T. J. McMahon, G. G. Hanson, J. Schwiening, R. K. Carnegie, J. A. Wilson, P. Weber, G. Giacomelli, P. Schenk, J. Steuerer, M. S. Dixit, J. C. Clayton, Frans Meijers, P. E.L. Clarke, U. C. Dunwoody, M. K. Jones, J. P. Martin, M. Tscheulin, S. De Jong, H. Przysiezniak, Marco Cuffiani, and S. L. Chu
Subjects: Quantum chromodynamics, Physics, Quark, Nuclear physics, Nuclear and High Energy Physics, Particle physics, Meson, Electron–positron annihilation, Multiplicity (mathematics), Bottom quark, Charged particle
Abstract: We have used data from the OPAL detector at LEP to reconstruct D∗ mesons and secondary vertices in jets. We have studied the hemispheres of the events opposite these jets and obtain values of the hemisphere charged particle multiplicity in Z0 → uu, dd, ss, Z0 → cc and Z0 → bb events of nuds = 10.41 ± 0.06 ± 0.09 ± 0.19; nc = 10.76 ± 0.20 ± 0.14 ± 0.19; nb = 11.81 ± 0.01 ± 0.12 ± 0.21 where the first errors are statistical, the second systmatic and the third a common scale uncertainty. We find the difference in total charged particle multiplicity between c and b quark events and light (u, d, s) quark events to be δcl = 0.69 ± 0.51 ± 0.35; δbl = 2.79 ± 0.12 ± 0.27. These results are compared to the predictions of various models and QCD based calculations.
Published: 1995
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47. Comparisons of the properties of final state photons in hadronic Z0 decays with predictions from matrix element calculations

Author: D. R. Rust, A. M. Lee, N. K. Watson, R. Van Kooten, D. M. Gingrich, Madjid Boutemeur, P. Berlich, Matthias Schröder, R. F. Hughes-Jones, C. Y. Chang, E. Lefebvre, C. Dallapiccola, M. Fanti, Margret Fincke-Keeler, S. Braibant, R. Bartoldus, P. G. Estabrooks, C. M. Hawkes, Daniel Lellouch, P. Taras, F. Odorici, R. W. Springer, J. D. Gillies, P. Szymanski, P. Igo-Kemenes, R. D. Heuer, Fabrizio Fabbri, Michael Kobel, Tohru Takeshita, H. Jeremie, Takehiko Mori, J. Steuerer, G. A. Snow, C. P. Ward, M. J. Oreglia, U. Maur, Georges Azuelos, Barry King, H. O. Ogren, Christoph Geich-Gimbel, D. L. Rees, S. Söldner-Rembold, P. M. Watkins, V. Zacek, K. W. Bell, Julie Kirk, H. Lafoux, R. J. Barlow, C. Jui, D. J. Miller, Stephen Lloyd, Tara Shears, W. Mohr, Stan Bentvelsen, J. C. Hill, Misao Sasaki, M. Tecchio, B. C. Shen, A. Posthaus, P. A. Hart, Siegfried Bethke, M. J. Pearce, E. do Couto e Silva, P. Poffenberger, D. E. Plane, T. Hilse, Silvia Arcelli, Ehud Duchovni, Shlomo Dado, D. Rigby, R. J. Hemingway, A. K. Honma, B. Nijjhar, W. G. Scott, J. R. Carter, G. N. Patrick, O. Biebel, Peter Fischer, G. M. Dallavalle, M. Jimack, O. Runolfsson, H. Mes, F. X. Gentit, Hans-Christian Schultz-Coulon, P. A. Elcombe, R. Lahmann, I. P. Duerdoth, G. A. Beck, D. C. Imrie, Randall Sobie, Michael Schulz, G. D. Lafferty, P. Schütz, C. Darling, B. W. Kennedy, F. Palmonari, P. Jovanovic, T. J. Smith, J. E. Conboy, A. Fürtjes, Alan Watson, Achim Stahl, P. Teixeira-Dias, P. Fath, M. J. Losty, Austin Ball, S. W. Gensler, Marco Cuffiani, C. Beeston, Peter Krieger, S. J. Hillier, T. Kobayashi, D. L. Wagner, Claudio Grandi, G. W. Wilson, U. Müller, W. P. Lai, G. P. Siroli, J. King, T. W. Pritchard, P. Mättig, Shoji Asai, D. Hochman, Manuella Vincter, Alessandro Montanari, M. Hauschild, S. L. Chu, Giora Mikenberg, H. Deng, B. Schmitt, F. Scharf, Christoph Schwick, I. J. Bloodworth, K. Stephens, C. Markus, Guenter Duckeck, J. M. Roney, O. C. Cooke, R. Mir, Reda Tafirout, F. S. Merritt, A. D. Schaile, O. Tousignant, M. Settles, J. Lauber, R. Kowalewski, J. Letts, A. S. Turcot, Yoram Rozen, C. K. Hargrove, Kiyotomo Kawagoe, W. Matthews, V. Gibson, S. W. O'Neale, M. Foucher, H. Takeda, Norbert Wermes, Sherry Towers, T. Kawamoto, K. J. Anderson, N. Capdevielle, J. von Krogh, M. A. Thomson, Paolo Giacomelli, F. G. Oakham, K. Ametewee, M. Hansroul, S. G. Clowes, V. H. Winterer, M. Fierro, J. E.G. Edwards, M. Yurko, W. R. Gibson, Junichi Kanzaki, E. L. Barberio, Gideon Alexander, E. K. U. Gross, Gregor Herten, Dave Robinson, D. Karlen, C. Burgard, P. W. Jeffreys, S. Orito, P. Weber, J. A. McKenna, M. Rosvick, A. Gaidot, C. H. Shepherd-Themistocleous, Paolo Capiluppi, T. Wlodek, M. Sproston, L. A. del Pozo, B. Wilkens, D. R. Ward, T. Kress, C. Sbarra, A. Beck, R. J. Homer, T. Behnke, J. C. Clayton, E. Heflin, Michael Dittmar, P. Bright-Thomas, R. M. Brown, G. Yekutieli, T. Tsukamoto, N. Tesch, Lorne Levinson, P. D. Phillips, P. Gagnon, J. E. Pilcher, J. J. Ward, P. Vikas, Gilles Beaudoin, A. A. Carter, Ron Folman, A. Skillman, Roger Jones, G. T. Zorn, N. J. Oldershaw, P. Utzat, H. M. Bosch, Wolfram Dietrich Zeuner, M. G. Rison, D. Axen, A. Jawahery, T. J. McMahon, R.J. Akers, Peter Sherwood, J. Schwiening, R. K. Carnegie, Alexander Wagner, J. Hagemann, J. Ludwig, K. Runge, P. Bock, J. A. Wilson, O. Schaile, B. Stockhausen, Paul Kyberd, F. K. Loebinger, M. Starks, G. G. Hanson, R. Giacomelli, A. J. Martin, J. Stamm, G. Giacomelli, John Allison, P. Schenk, A. Buijs, D. M. Strom, C. Stegmann, R. G. Kellogg, Andris Skuja, Stefano Marcellini, G. D. Long, H. Fukui, Tetsuro Mashimo, M. S. Dixit, M. W. Redmond, Frans Meijers, W. Gorn, P. E.L. Clarke, U. C. Dunwoody, M. K. Jones, P. Scharff-Hansen, A. M. Smith, J. P. Martin, G. Vasseur, B. Lorazo, M. Tscheulin, James Pinfold, S. De Jong, Richard Keeler, D. G. Fong, J. Gascon, J. W. Gary, D. S. Koetke, Marcello Mannelli, J. E. Duboscq, H. Przysiezniak, R. Howard, Claude Leroy, J. P. Pansart, J. G. Layter, C. Charlesworth, P. S. Wells, Terry Richard Wyatt, Gideon Bella, H. J. Burckhart, Jacqueline Batley, Xinchou Lou, Dave Charlton, R. Bürgin, B. Fabbro, N. I. Geddes, N. L. Rodning, B. Poli, A. I. McNab, A. M. Rossi, J. Goldberg, H. M. Fischer, A. Michelini, B. Nellen, S. A. Robins, P. Leblanc, H. G. Evans, M. J. Goodrick, I. Cohen, Gunter Wolf, S. Wotton, Erez Etzion, Stefan Kluth, Shlomit Tarem, C. J. Oram, R. P. Middleton, Sachio Komamiya, Theodoros Geralis, E. Ros, T. P. Kokott, A. Luig, A. Yeaman, M. F. Turner-Watson, M. Morii, Peter R Hobson, and P. Routenburg
Subjects: Physics, Particle physics, Photon, Physics and Astronomy (miscellaneous), Electron–positron annihilation, Hadron, Elementary particle, Jet (particle physics), Nuclear physics, Phase space, High Energy Physics::Experiment, Field theory (psychology), Quantum field theory, Engineering (miscellaneous), Particle Physics - Experiment
Abstract: The properties of hadronic Z0 decays with final state photons, measured with OPAL at LEP, have been compared with predictions from two different matrix element calculations ofO(ααs). Two calculations, GNJETS and EEPRAD, have been investigated which use different schemes to restrict the phase space around the poles of the cross section. Assuming the E0-JADE jet definition, both calculations describe the data well in large regions of phase space forycut values around 0.06. For very large and very small jet-photon masses some deviations from the predictions have been found, indicating the importance of higher order corrections. Significant differences between the calculations are only apparent in the predicted rate of 1-jet plus photon events. The rate is higher in GNJETS which reproduces the data better than EEPRAD.
Published: 1995
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48. Measurement of $$\Gamma (Z^0 \to b\bar b)/\Gamma (Z^0 \to hadrons)$$ using a double tagging method

Author: H. J. Burckhart, Jacqueline Batley, P. Igo-Kemenes, H. Jeremie, P. Scharff-Hansen, R. E. Hughes-Jones, U. Maur, A. Höcker, D. Axen, A. Jawahery, R. Van Kooten, E. do Couto e Silva, D. Pitman, A. M. Smith, Shlomo Dado, Xinchou Lou, Peter Sherwood, R. W. Springer, Alexander Wagner, M. H. Lehto, G. Vasseur, H. Mes, J. Hagemann, J. Ludwig, K. Runge, P. Bock, Giora Mikenberg, B. Lorazo, I. P. Duerdoth, G. G. Hanson, A. I. McNab, J. Goldberg, Otmar Biebel, T. G. Shears, B. Nellen, P. Leblanc, D. G. Charlton, D. L. Wagner, H. Deng, R. Humbert, D. M. Gingrich, F. Liu, R. Mir, J. von Krogh, Andris Skuja, H. Przysiezniak, P. Schenk, S. Braibant, C. M. Hawkes, D. A. Hinshaw, Daniel Lellouch, G. A. Snow, C. P. Ward, R. Bartoldus, D. L. Rees, S. G. Clowes, J. Lauber, M. Fierro, M. S. Dixit, Z. Li, Frans Meijers, G. D. Long, Tetsuro Mashimo, H. G. Evans, Dave Robinson, Takehiko Mori, P. Berlich, H. Takeda, F. G. Oakham, H. O. Ogren, M. J. Goodrick, M. Yurko, P. W. Jeffreys, T. J. McMahon, M. Hauschild, I. Cohen, M. F. Turner-Watson, M. Morii, J. G. Layter, S. W. O'Neale, E. L. Barberio, Christoph Geich-Gimbel, Norbert Wermes, Sherry Towers, T. Kawamoto, K. J. Anderson, Hans-Christian Schultz-Coulon, Randall Sobie, Michael Schulz, G. D. Lafferty, J. Schwiening, Peter R Hobson, R. Kowalewski, J. Hart, R. K. Carnegie, T. Behnke, C. Markus, P. Le Du, B. Fabbro, C. Charlesworth, E. Lefebvre, C. Dallapiccola, J. D. Gillies, J. A. Wilson, W. Gorn, P. Routenburg, D. R. Rust, T. W. Pritchard, A. Skillman, P. A. Hart, P. Bright-Thomas, I. J. Bloodworth, S. Orito, M. Rosvick, Tohru Takeshita, F. Odorici, D. E. Plane, J. C. Clayton, G. Giacomelli, S. L. Chu, Gunter Wolf, F. X. Gentit, Guenter Duckeck, A. Buijs, Gideon Alexander, P. Bentkowski, T. Wlodek, Paolo Capiluppi, R. J. Barlow, D. M. Strom, C. Stegmann, C. Y. Chang, M. J. Pearce, D. J. Miller, G. M. Dallavalle, M. Sproston, J. J. Ward, M. A. Thomson, A. M. Lee, M. Settles, Yoram Rozen, M. Foucher, P. Gagnon, R.J. Akers, M. J. Oreglia, P. E.L. Clarke, U. C. Dunwoody, M. K. Jones, J. P. Martin, Georges Azuelos, Barry King, Paolo Giacomelli, T. Tsukamoto, H. Fukui, M. Hansroul, Michael Kobel, N. Tesch, S. Wotton, Silvia Arcelli, R. Ströhmer, P. A. Elcombe, O. Schaile, J. E. Conboy, A. Fürtjes, S. De Jong, J. F. Kral, K. W. Bell, C. Sbarra, V. H. Winterer, T. Hilse, G. T. Zorn, D. Rigby, R. J. Hemingway, O. Runolfsson, G. W. Wilson, D. Karlen, C. Burgard, B. W. Kennedy, A. Yeaman, P. D. Grannis, J. R. Carter, G. N. Patrick, M. Fanti, J. Becker, Erez Etzion, Stephen Lloyd, M. Tecchio, Robert M Brown, Matthias Schröder, James Pinfold, A. J. Martin, P. Jovanovic, H. Lafoux, H. M. Bosch, Wolfram Dietrich Zeuner, D. G. Fong, F. S. Merritt, Michael Dittmar, Austin Ball, C. H. Shepherd-Themistocleous, C. Beeston, Peter Krieger, Claudio Grandi, F. Scharf, Stefan Kluth, Shlomit Tarem, J. C. Hill, Misao Sasaki, P. Poffenberger, P. Szymanski, Peter Fischer, Manuella Vincter, Alessandro Montanari, Sachio Komamiya, G. Yekutieli, B. C. Shen, Theodoros Geralis, E. Ros, A. T. Watson, A. D. Schaile, A. A. Carter, Ron Folman, Roger Jones, J. Steuerer, S. Rossberg, C. J. Oram, R. J. Homer, J. Gascon, H. von der Schmitt, Gregor Herten, P. Schütz, N. K. Watson, J. A. McKenna, Eilam Gross, R. P. Middleton, B. Wilkens, R. Howard, C. Darling, T. J. Smith, J. P. Pansart, T. P. Kokott, C. Jui, A. Luig, M. G. Rison, K. Stephens, Claude Leroy, A. Gaidot, Siegfried Bethke, A. K. Honma, J. E. Pilcher, Stan Bentvelsen, Ehud Duchovni, R. D. Heuer, J. R. McNutt, W. Mohr, Fabrizio Fabbri, P. Mättig, Shoji Asai, D. Van den plas, Margret Fincke-Keeler, W. R. Gibson, A. Posthaus, B. Nijjhar, W. G. Scott, A. Astbury, J. M. Roney, M. Jimack, A. Beck, H. Ihssen, Marco Cuffiani, V. Gibson, E. Heflin, J. W. Gary, Lorne Levinson, U. Müller, P. D. Phillips, P. S. Wells, Gilles Beaudoin, Madjid Boutemeur, D. R. Ward, Terry Richard Wyatt, S. W. Gensler, S. J. Hillier, T. Kobayashi, Marcello Mannelli, J. E. Duboscq, M. Coupland, C. K. Hargrove, D. Hochman, P. G. Estabrooks, R. K. Keeler, P. Pfister, P. M. Watkins, M. J. Losty, C. Moisan, G. A. Beck, Achim Stahl, P. Teixeira-Dias, B. Schmitt, John Allison, R. G. Kellogg, D. S. Koetke, Stefano Marcellini, James Letts, J. Mildenberger, R. Lahmann, M. W. Redmond, D. C. Imrie, G. P. Siroli, J. King, B. Stockhausen, Paul Kyberd, Christoph Schwick, F. K. Loebinger, A. M. Rossi, H. M. Fischer, A. Michelini, S. A. Robins, R. Giacomelli, N. I. Geddes, B. Poli, Kiyotomo Kawagoe, P. Weber, and Gideon Bella
Subjects: Physics, Systematic error, Particle physics, Muon, Physics and Astronomy (miscellaneous), Model prediction, Electron–positron annihilation, High Energy Physics::Phenomenology, Hadron, Elementary particle, Standard Model, Nuclear physics, High Energy Physics::Experiment, Engineering (miscellaneous), Particle Physics - Experiment, Bar (unit)
Abstract: The fraction of$Z^0 \to b\bar b$; events in hadronicZ0 decays has been measured using the data collected by OPAL in 1992 and 1993. The presence of electrons or muons from semileptonic decays of bottom hadrons and the detection of bottom hadron decay vertices were used together to obtain an event sample enriched in$Z^0 \to b\bar b$ decays. To reduce the systematic error on the measurement of the$Z^0 \to b\bar b$ fraction, the efficiency of the$b\bar b$ event tagging was obtained from the data by comparing the numbers of events having a bottom signature in either one or both thrust hemispheres. A value of $$\frac{{\Gamma (Z^0 \to b\bar b)}}{{\Gamma (Z^0 \to hadrons)}} = 0.2171 \pm 0.0021 \pm 0.0021$$ was obtained, where the first error is statistical and the second systematic. The uncertainty on the decay width$\Gamma (Z^0 \to c\bar c)$ is not included in these errors. A fractional variation of this width by ±8% about its Standard Model prediction would result in a variation of the measured$Z^0 \to b\bar b$ fraction of ±0.0015.
Published: 1995
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49. Measurement of the hadronic decay current in τ−→π− − + v τ

Author: Michael Dittmar, G. Yekutieli, A. A. Carter, F. S. Merritt, Ron Folman, Roger Jones, T. J. Smith, P. Utzat, M. G. Rison, K. Stephens, A. I. McNab, P. Szymanski, J. A. McKenna, P. A. Elcombe, S. Braibant, R. Kowalewski, T. J. McMahon, J. Schwiening, J. Goldberg, R. K. Carnegie, J. A. Wilson, O. C. Cooke, G. W. Wilson, N. Capdevielle, J. von Krogh, Andris Skuja, Dave Robinson, M. Hauschild, L. A. del Pozo, C. Jui, Stan Bentvelsen, T. Hilse, R. Bartoldus, B. Nellen, P. Leblanc, K. Ametewee, Kiyotomo Kawagoe, Silvia Arcelli, C. Markus, Gideon Alexander, P. Igo-Kemenes, Gideon Bella, G. D. Long, P. E.L. Clarke, O. Runolfsson, R. Van Kooten, H. J. Burckhart, G. A. Snow, Jacqueline Batley, Paolo Capiluppi, H. Jeremie, N. J. Oldershaw, Matthias Schröder, B. Stockhausen, Paul Kyberd, F. K. Loebinger, R.J. Akers, R. E. Hughes-Jones, U. Maur, Reda Tafirout, H. O. Ogren, Christoph Geich-Gimbel, B. C. Shen, F. Scharf, C. Beeston, C. P. Ward, D. L. Rees, V. Gibson, Sachio Komamiya, E. Lefebvre, A. S. Turcot, Claudio Grandi, U. C. Dunwoody, M. K. Jones, J. P. Martin, Theodoros Geralis, E. Ros, A. T. Watson, S. Söldner-Rembold, Tetsuro Mashimo, M. J. Oreglia, E. do Couto e Silva, O. Tousignant, O. Schaile, P. Weber, N. I. Geddes, M. Tscheulin, Siegfried Bethke, H. G. Evans, M. J. Goodrick, M. Yurko, Xinchou Lou, A. D. Schaile, P. W. Jeffreys, R. Giacomelli, A. K. Honma, B. Nijjhar, W. R. Gibson, W. G. Scott, N. L. Rodning, F. Odorici, F. X. Gentit, M. Starks, J. E. Conboy, S. De Jong, Paolo Giacomelli, I. Cohen, B. Poli, W. P. Lai, A. Fürtjes, V. H. Winterer, M. Hansroul, A. Beck, P. Bright-Thomas, G. Mikenberg, E. Heflin, S. W. O'Neale, D. M. Gingrich, Dave Charlton, D. R. Ward, R. M. Brown, J. M. Roney, Lorne Levinson, T. Kress, W. Gorn, J. J. Ward, P. Vikas, K. J. Anderson, W. Matthews, Shlomo Dado, C. H. Shepherd-Themistocleous, R. Bürgin, B. Fabbro, T. P. Kokott, Gilles Beaudoin, D. Rigby, R. J. Hemingway, A. M. Rossi, T. Tsukamoto, H. M. Fischer, J. R. Carter, A. Skillman, H. Przysiezniak, A. Luig, Madjid Boutemeur, Gregor Herten, M. A. Thomson, A. Michelini, R. J. Homer, P. Berlich, D. Axen, M. J. Losty, G. N. Patrick, J. C. Clayton, S. A. Robins, B. W. Kennedy, P. G. Estabrooks, R. K. Keeler, P. Jovanovic, B. Wilkens, E. K. U. Gross, A. Gaidot, D. R. Rust, A. Jawahery, P. S. Wells, Margret Fincke-Keeler, M. W. Redmond, P. O. Phillips, Hans-Christian Schultz-Coulon, Otmar Biebel, P. M. Watkins, J. E. Pilcher, S. G. Clowes, R. Lahmann, M. Fierro, Austin Ball, T. Wlodek, M. Sproston, J. E.G. Edwards, C. Y. Chang, D. C. Imrie, Randall Sobie, Michael Schulz, G. D. Lafferty, D. E. Plane, H. Mes, James Pinfold, U. Müller, G. P. Siroli, J. King, Peter Sherwood, John Allison, Christoph Schwick, Peter Krieger, I. P. Duerdoth, G. M. Dallavalle, D. G. Fong, D. Hochman, T. W. Pritchard, A. J. Martin, Alexander Wagner, Terry Richard Wyatt, P. Taras, N. Tesch, P. Fath, J. Gascon, D. L. Wagner, Guenter Duckeck, J. Hagemann, J. Ludwig, N. K. Watson, Michael Kobel, A. M. Lee, K. Runge, P. Bock, R. G. Kellogg, Manuella Vincter, J. W. Gary, R. W. Springer, Stefano Marcellini, D. S. Koetke, Marcello Mannelli, J. E. Duboscq, Alessandro Montanari, Tohru Takeshita, C. K. Hargrove, J. G. Layter, H. Deng, P. Scharff-Hansen, P. A. Hart, W. Mohr, Georges Azuelos, Julie Kirk, Y. Routenburg, H. Lafoux, M. J. Pearce, Barry King, C. Dallapiccola, A. Buijs, C. Charlesworth, M. Fanti, A. M. Smith, K. W. Bell, A. Posthaus, D. M. Strom, C. Stegmann, G. A. Beck, Achim Stahl, G. Vasseur, B. Lorazo, P. Teixeira-Dias, J. D. Gillies, J. C. Hill, Misao Sasaki, H. Fukui, P. Poffenberger, T. Behnke, G. G. Hanson, A. Yeaman, B. Schmitt, G. Giacomelli, J. Letts, P. Schenk, R. J. Barlow, Peter Fischer, R. D. Heuer, D. J. Miller, M. S. Dixit, Frans Meijers, P. Schütz, P. Gagnon, Fabrizio Fabbri, R. Mir, Norbert Wermes, Sherry Towers, T. Kawamoto, J. Lauber, G. T. Zorn, T. G. Schears, H. Takeda, M. F. Turner-Watson, M. Morii, F. G. Oakham, H. M. Bosch, Wolfram Dietrich Zeuner, E. L. Barberio, Peter R Hobson, R. Howard, Claude Leroy, S. Orito, J. P. Pansart, M. Rosvick, Stephen Lloyd, M. Tecchio, Ehud Duchovni, M. Jimack, F. Palmonari, S. W. Gensler, S. J. Hillier, T. Kobayashi, C. Darling, P. Mättig, Shoji Asai, I. J. Bloodworth, M. Settles, Yoram Rozen, M. Foucher, Junichi Kanzaki, D. Karlen, C. Burgard, C. M. Hawkes, Daniel Lellouch, Takehiko Mori, V. Zacek, J. Steuerer, Marco Cuffiani, S. L. Chu, Erez Etzion, Stefan Kluth, Shlomit Tarem, C. J. Oram, R. P. Middleton, Gunter Wolf, S. Wotton, and C. Sbarra
Subjects: Physics, Particle physics, Physics and Astronomy (miscellaneous), media_common.quotation_subject, Electron–positron annihilation, Hadron, Dalitz plot, Parity (physics), Elementary particle, Asymmetry, Nuclear physics, Amplitude, Neutrino, Engineering (miscellaneous), media_common
Abstract: The decay τ−→π−−+vτ has been studied using data collected with the OPAL detector at LEP during 1992 and 1993. The hadronic structure functions for this decay are measured model independently assuming G-parity invariance and neglecting scalar currents. Simultaneously the parity violating asymmetry parameter is determined to be$\gamma VA = 1.08 _{ - 0.41 - 0.25}^{ + 0.46 + 0.14} $, consistent with the Standard Model prediction of γVA=1 for left-handed tau neutrinos. Models of Kuhn and Santamaria and of Isgur et al. are used to fit distributions of the invariant 3π mass as well as 2π mass projections of the Dalitz plot. The model dependent mass and width of thea1 resonance are measured to be$m_{a_1 } = 1.266 \pm 0.014_{ - 0.002}^{ + 0.012} $ GeV and$\Gamma _{a_1 } = 0.610 \pm 0.049_{ - 0.019}^{ + 0.053} $ GeV for the Kuhn and Santamaria model and$m_{a_1 } = 1.202 \pm 0.009_{ - 0.001}^{ + 0.009} $ GeV and$\Gamma _{a_1 } = 0.422 \pm 0.023_{ - 0.004}^{ + 0.033} $ GeV for the Isgur et al. model. The model dependent values obtained for the parity violating asymmetry parameter are γVA=0.87±0.27−0.06+0.05 for the Kuhn and Santamaria model and γVA=1.10±0.31−0.14+0.13 for the Isgur et al. model. Within the Isgur et al. model the ratio of theS-andD-wave amplitudes is measured to beD/S=−0.09±0.03±0.01.
Published: 1995
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50. Determination of event shape distributions and α s b from $$Z^0 \to b\bar b$$ events at LEP

Author: A. Yeaman, P. D. Grannis, T. J. Smith, Sachio Komamiya, Theodoros Geralis, E. Ros, Z. Li, M. F. Turner-Watson, M. Morii, Peter R Hobson, P. Routenburg, Otmar Biebel, K. Stephens, B. C. Shen, T. P. Kokott, A. Luig, D. G. Charlton, D. L. Wagner, J. R. McNutt, A. Astbury, H. Mes, H. Deng, R. Humbert, Siegfried Bethke, N. K. Watson, U. Müller, A. K. Honma, J. Mildenberger, D. Rigby, R. J. Hemingway, I. P. Duerdoth, A. J. Martin, B. Nijjhar, W. G. Scott, J. M. Roney, Margret Fincke-Keeler, James Pinfold, C. Y. Chang, R. Lahmann, D. C. Imrie, J. E. Duboseq, G. Mikenberg, T. J. McMahon, B. W. Kennedy, M. Yurko, D. G. Fong, J. Gascon, H. von der Schmitt, P. Jovanovic, C. K. Hargrove, G. G. Hanson, F. Liu, G. Giacomelli, Gunter Wolf, F. X. Gentit, N. I. Geddes, M. W. Redmond, J. W. Gary, Michael Kobel, S. Braibant, Norbert Wermes, Sherry Towers, Austin Ball, P. W. Jeffreys, T. Kobayashi, G. P. Siroli, J. King, P. Igo-Kemenes, T. Kawamoto, B. Stockhausen, Paul Kyberd, F. K. Loebinger, Peter Krieger, P. Schenk, M. J. Losty, J. Schwiening, P. A. Hart, Christoph Schwick, H. Lafoux, P. Bright-Thomas, D. A. Hinshaw, Manuella Vincter, Alessandro Montanari, R. K. Carnegie, M. J. Pearce, F. S. Merritt, E. Lefebvre, W. Mohr, G. A. Snow, C. P. Ward, H. Jeremie, S. Orito, D. R. Ward, P. Poffenberger, R. Giacomelli, M. Rosvick, A. Posthaus, J. A. Wilson, S. Wotton, B. Poli, M. S. Dixit, D. L. Rees, R. E. Hughes-Jones, U. Maur, F. Odorici, R. Mir, P. S. Wells, S. W. O'Neale, Frans Meijers, Matthias Schröder, J. J. Ward, Hans-Christian Schultz-Coulon, Gregor Herten, M. A. Thomson, Marcello Mannelli, R. W.L. Jones, P. Pfister, D. R. Rust, J. C. Clayton, H. M. Fischer, Kiyotomo Kawagoe, Andris Skuja, J. Lauber, A. Höcker, Tohru Takeshita, J. A. McKenna, A. Michelini, A. Skillman, V. Gibson, A. I. McNab, R. G. Kellogg, G. D. Long, B. Wilkens, Terry Richard Wyatt, A. T. Watson, J. Goldberg, C. Darling, D. S. Koetke, Georges Azuelos, J. G. Layter, K. J. Anderson, E. do Couto e Silva, Michael Schulz, M. J. Oreglia, E. K. U. Gross, Tetsuro Mashimo, Stefano Marcellini, J. Steuerer, H. Takeda, B. Nellen, Barry King, James Letts, S. A. Robins, Shlomo Dado, P. Leblanc, T. Wlodek, F. G. Oakham, M. Coupland, M. Sproston, E. L. Barberio, J. P. Pansart, T. Behnke, K. W. Bell, D. Axen, A. Jawahery, R. J. Barlow, C. Charlesworth, H. Przysiezniak, S. G. Clowes, J. Hart, C. Dallapiccola, J. C. Hill, G. N. Patrick, J. R. Carter, M. Fierro, P. Weber, H. G. Evans, N. Tesch, J. E. Pilcher, W. Gorn, J. D. Gillies, M. J. Goodrick, P. Mättig, I. Cohen, Peter Sherwood, Peter Fischer, Marco Cuffiani, J. von Krogh, T. Hilse, P. A. Elcombe, P. Schütz, Shoji Asai, R. W. Springer, Alexander Wagner, P. E.L. Clarke, U. C. Dunwoody, M. K. Jones, O. Runolfsson, A. M. Lee, A. Buijs, D. M. Strom, A. Gaidot, J. Hagemann, J. Ludwig, K. Runge, P. Bock, J. P. Martin, M. Sasaki, Erez Etzion, C. Stegmann, David Robinson, Stefan Kluth, J. Becker, S. L. Chu, P. Scharff-Hansen, A. M. Rossi, C. Beeston, C. M. Hawkes, T. W. Pritchard, S. De Jong, Daniel Lellouch, Shlomit Tarem, H. Fukui, Claudio Grandi, F. Scharf, C. Sbarra, T. Tsukamoto, S. Rossberg, C. J. Oram, Madjid Boutemeur, Takehiko Mori, P. Gagnon, A. D. Schaile, R. Bartoldus, Michael Dittmar, R. P. Middleton, D. J. Miller, J. Allison, R. Ströhmer, G. Yekutieli, A. M. Smith, P. G. Estabrooks, R. K. Keeler, M. Hauschild, G. Vasseur, D. Hochman, B. Lorazo, H. O. Ogren, Christoph Geich-Gimbel, G. T. Zorn, P. M. Watkins, C. Markus, H. M. Bosch, Wolfram Dietrich Zeuner, R. J. Sobie, Silvia Arcelli, R. Howard, Claude Leroy, I. J. Bloodworth, R. Van Kooten, G. D. Lafferty, Paolo Giacomelli, D. Pitman, Guenter Duckeck, S. L. Lloyd, M. H. Lehto, J. E. Conboy, R.J. Akers, M. Settles, M. Hansroul, A. Fürtjes, P. Le Du, B. Fabbro, T. G. Shears, C. H. Shepherd-Themistocleous, D. M. Gingrich, P. Szymanski, R. J. Homer, C. Moisan, Gideon Bella, G. A. Beck, Achim Stahl, P. Teixeira-Dias, M. Tecchio, P. Berlich, H. J. Burckhart, M. Fanti, B. Schmitt, Jacqueline Batley, O. Schaile, C. Jui, Stan Bentvelsen, R. D. Heuer, Fabrizio Fabbri, D. Van den plas, R. Kowalewski, Xinchou Lou, V. H. Winterer, W. R. Gibson, A. Beck, E. Heflin, Gideon Alexander, R. M. Brown, Paolo Capiluppi, Lorne Levinson, P. D. Phillips, Gilles Beaudoin, Ehud Duchovni, M. Jimack, H. Ihssen, S. W. Gensler, D. E. Plane, P. Bentkowski, S. J. Hillier, G. M. Dallavalle, Yoram Rozen, M. Foucher, G. W. Wilson, D. Karlen, C. Burgard, A. A. Carter, Ron Folman, and M. G. Rison
Subjects: Physics, Quark, Particle physics, Physics and Astronomy (miscellaneous), High Energy Physics::Lattice, Electron–positron annihilation, High Energy Physics::Phenomenology, Hadron, Elementary particle, Jet (particle physics), Vertex (geometry), Nuclear physics, High Energy Physics::Experiment, Parton shower, Engineering (miscellaneous), Event (probability theory)
Abstract: In hadronic Z0 decays collected by the OPAL experiment at LEP, event shape variables such as jet rates, jet masses, thrust and the energy-energy correlation for $$Z^0 \to b\bar b$$ events are compared to those for all flavours using secondary vertex information to tag the b quarks. The measured distributions are found to be well described by anO"(α s ) calculation for heavy quarks as well as by parton shower simulations. We also determine the ratio of the strong coupling constant for b quarks and all quarks, α b /α incl , from these distributions. We find $$\alpha _s^b /\alpha _s^{incl} = 0.994 \pm 0.005_{ - 0.012}^{ + 0.010} ,$$ where the errors are the statistical and systematic errors. The result can be converted into the ratio for b quarks relative to the complementary flavours udsc α b /α udsc =0.992±0.007 -0.015 +0.013 .
Published: 1995
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