Search

Your search keyword '"M., Hapke"' showing total 256 results
Start Over Author "M., Hapke"
256 results on '"M., Hapke"'

1. Escalating uncertainties require institutional transformation to support epistemological pluralism

Author

Jennifer F. Brewer and Holly M. Hapke

Subjects
Oceanography, GC1-1581, Environmental sciences, GE1-350
Abstract

As marine conservation challenges intensify with accelerating anthropogenic change, informing public deliberation about difficult trade-offs requires commitment to epistemological pluralism. Robust integration of social sciences can improve the realism of policy debates by explicating a range of potential social-ecological outcomes. Funders have long incentivized interdisciplinarity, yet progress is insufficient and embedded in a political economy of knowledge production. Failure to substantively address inequities can stymie collaboration. Institutional expectations for promotion and tenure rarely recognize the extent to which deep engagement transforms epistemological norms and scholarly outputs. Several organizations and programs offer relevant experience and resources. Senior scholars can use their privilege to broaden the public accountability of science.

Published
2024
Full Text
View/download PDF

2. Technological transformation and changing social relations in the ring seine fishery of Kerala, India

Author

Nikita Gopal, Holly M. Hapke, and Leela Edwin

Subjects
Geography, Planning and Development, Fish food system, Women, Management, Monitoring, Policy and Law, Development, Aquatic Science, Ring seine fishery, Water Science and Technology
Abstract

Across the Global South, commercial development and technological innovations are transforming fish food systems in ways that significantly impact the livelihoods of small-scale producers and the food security of the poor. A crucial but understudied aspect of such transformations is the social relations in which fish food systems are embedded. Food system transformations change power relations and rework gendered economic roles and divisions of labour in ways that often marginalise women and other vulnerable groups. In this paper, we draw on feminist studies of gender and technology and feminist commodity chain analysis to investigate the impact of technological transformation on social relations in the ring seine fishery of Kerala, India. Kerala's ring seine fishery specifically targets small pelagics like sardine, mackerel, and anchovies, which have been identified as important to the food security and nutrition of the poor. Since the mid-1980s, when the ring seine was first introduced to enable small-scale fishers to compete with mechanised trawlers, these fishing units have expanded both in terms of numbers and in size, largely as a result of locally-driven technological innovation and adaptation. Though traditional arrangements of labour deployment and wage sharing have remained, rising competition and differentiation between fishermen have ensued. At the same time, changes in processing, distribution, and trade have reworked women's economic roles and position in the fishery, and questions about long-term profitability and sustainability have necessitated interventions in governance at various levels. Tracing the trajectory of technological innovation and changing social relations through the value chain, we assessed the gendered implications of fish food system transformations for livelihoods. We found that the increase in dimensions of the new gear increased both investments and operational costs of the fishing units rendering several of them uneconomical. Time-tested social norms have also changed as competition increased, which is much more pronounced between the smaller and larger fishing vessels. The traditional wage sharing pattern still remains ensuring income security for fishermen who cannot find work as crew on these fishing vessels. Women, however, have been most affected by the changes as they no longer are able to access the fish resource as earlier for engaging in post-harvest activities, such as marketing and fish drying.

Published
2023

3. Women’s work in small-scale fisheries: a framework for accounting its value

Author

Holly M. Hapke and Carmen Pedroza-Gutiérrez

Subjects
Cultural Studies, Gender Studies, Fishery, Arts and Humanities (miscellaneous), Work (electrical), Women's work, Scale (social sciences), Value (economics), Household income, %22">Fish , Business, Productivity, Demography
Abstract

Women play an important role in small-scale fisheries around the world. Their work along the entire fish value chain contributes to the productivity of the sector and enhances household income. But...

Published
2021

5. Expanding the horizons for women in fisheries and aquaculture

Author

Nikita Gopal, Kyoko Kusakabe, Holly M. Hapke, Meryl J Williams, and Surendran Rajaratnam

Subjects
business.industry, 050204 development studies, Aquatic ecosystem, Fish farming, 05 social sciences, Distribution (economics), Development, Gender Studies, Fishery, Geography, Aquaculture, 0502 economics and business, 050202 agricultural economics & policy, business
Abstract

Women are present in all phases of fish production, processing and distribution, and contribute to the generation of wealth, the preservation of aquatic ecosystems, and the maintenance of household...

Published
2020

7. Gendered livelihoods in the global fish-food economy: a comparative study of three fisherfolk communities in Kerala, India

Author

Holly M. Hapke and Devan Ayyankeril

Subjects
Resource (biology), Commodity chain, 050204 development studies, 05 social sciences, Geography, Planning and Development, Fishing, 0507 social and economic geography, Management, Monitoring, Policy and Law, Development, Aquatic Science, Livelihood, Globalization, Geography, Economic data, Work (electrical), Economy, 0502 economics and business, 050703 geography, Division of labour, Water Science and Technology
Abstract

Over the past several decades, global economic relations within the fisheries sector have intensified creating a “global fish-food economy”. Until recently, relatively little attention has been paid to the gendered spatial relations underlying this system and the differential way globalization shapes men and women fish workers’ livelihood options. This paper integrates insights from feminist commodity chain analysis and livelihood analysis to analyze household-level economic data and gendered patterns of labor among three fisherfolk communities in Trivandrum District, Kerala, India. The objective is to investigate the diverse impacts of globalization within fisheries on women and men in local fishing communities. Different gender divisions of labor across the three communities studied inform very different livelihood strategies in response to economic transformations. Thus, globalization in the fisheries plays out differently for men and women in different fishing communities as a result of different configurations of gender, work, culture, identity, and economy and the different ways households and communities are connected to fish economies at different scales. Identifying these differences offers a means by which we might broaden our theoretical understanding of the gendered nature of globalization in resource-based economies.

Published
2018

8. State-Led Development and the Cultural Economy of Trade in a South Indian Fishery

Author

Holly M. Hapke

Subjects
Ecology, media_common.quotation_subject, Geography, Planning and Development, Management, Monitoring, Policy and Law, Commercialization, Development policy, Fishery, Intervention (law), Economy, State (polity), %22">Fish , Economic impact analysis, Business, Law, media_common
Abstract

Throughout the 1960s, 1970s, and 1980s, a number of newly independent, post-colonial nations pursued state-led economic development. In the fisheries sector, such initiatives were based on growth-o...

Published
2016

10. Guest Editorial: Engendering Security in Fisheries and Aquaculture

Author

Meryl J Williams, Siri Gerrard, Susana Siar, Nikita Gopal, Louis Lebel, Kyoko Kusakabe, Natasha Stacey, Anne Coles, Ram C. Bhujel, Marilyn Porter, and Holly M. Hapke

Subjects
0106 biological sciences, Ecology, business.industry, 010604 marine biology & hydrobiology, SH1-691, 04 agricultural and veterinary sciences, Aquatic Science, 01 natural sciences, Fishery, Aquaculture, Political science, Aquaculture. Fisheries. Angling, 040102 fisheries, 0401 agriculture, forestry, and fisheries, business, Food Science
Abstract

This Special Issue of Asian Fisheries Science journal comprises 25 papers and a report based on the presentations and posters of the 6th Global Symposium on Gender in Aquaculture and Fisheries (GAF6) held during the 11th Asian Fisheries and Aquaculture Forum, August 2016, Bangkok, Thailand. GAF6 was the eighth women/gender Symposium organised by the Asian Fisheries Society (AFS). For each previous event, the proceedings or selected papers have been published (Williams et al. 2001; Williams et al. 2002; Choo et al. 2006; Choo et al. 2008, Williams et al. 2012; Gopal et al. 2014; Gopal et al. 2016).

Published
2017

11. Theorizing Patriarchy: Development Paradoxes and the Geography of Gender in South Asia

Author

Holly M. Hapke

Subjects
education.field_of_study, South asia, 050204 development studies, media_common.quotation_subject, 05 social sciences, Patriarchy, Population, Social change, Developing country, Gender studies, Development, Ideal (ethics), Gender Studies, State (polity), 0502 economics and business, 050202 agricultural economics & policy, Sociology, Social science, education, Socioeconomic status, media_common
Abstract

The status of women in the Indian state of Kerala has long been portrayed as ideal in an otherwise highly patriarchal region of the world. And yet, as feminist scholars and activists in Kerala have...

Published
2013

12. Petty Traders, Gender, and Development in a South Indian Fishery*

Author

Holly M. Hapke

Subjects
Economics and Econometrics, Economic growth, business.industry, Geography, Planning and Development, Economic transformation, Distribution (economics), Commercialization, Capitalist development, Work (electrical), Gender and development, Economics, Production (economics), business, Ecological crisis
Abstract

In this paper I examine the impact of mechanization and commercialization on small-scale fish traders in Kerala, India, with special emphasis on gender and the impact of economic transformation on women fish traders. I explore the relationship of women's work in distribution to production and how this has changed with capitalist development. I argue that because women's roles in the fish economy have been overlooked, they have experienced economic marginalization at the same time that their labor has become increasingly important for household survival. Such marginalization stems from a qualitative change that has taken place in their relationship to production and marketing as a result of capitalist development and the ecological crisis it has engendered.

Published
2009

13. Book Reviews

Author

Gabrielle Groves and Holly M. Hapke

Subjects
Gender Studies, Development
Published
2009

14. An Introduction to Human-Environment Geography : Local Dynamics and Global Processes

Author

William G. Moseley, Eric Perramond, Holly M. Hapke, Paul Laris, William G. Moseley, Eric Perramond, Holly M. Hapke, and Paul Laris

Subjects
Human ecology--Textbooks, Human geography--Textbooks
Abstract

This introductory level text explores various theoretical approaches to human-environment geography, demonstrating how local dynamics and global processes influence how we interact with our environments. Introduces students to fundamental concepts in environmental geography and science Explores the core theoretical traditions within the field, along with major thematic issues such as population, food and agriculture, and water resources Offers an engaging and unique view of the spatial relationships between humans and their environment across geographical locations around the world Includes a variety of real-world policy questions and emphasizes geography's strong tradition of field work by featuring prominent nature-society geographers in guest field notes

Published
2014

15. Gender, the work‐life course, and livelihood strategies in a South Indian fish market

Author

Holly M. Hapke, Devan Ayyankeril, and Sustainable Agriculture and Natural Resource Management (SANREM) Knowledgebase

Subjects
Cultural Studies, Fish traders, Fishing, Fisheries, Developing country, Observation, Social class, Gender Studies, Arts and Humanities (miscellaneous), Economics, Women, Human resources, Socioeconomics, Livelihoods, Socioeconomic status, Demography, Mobility, business.industry, Economic life history, Caste, Gender, Men, Livelihood, Marketing and trade, Farm/Enterprise Scale, Construct (philosophy), business, Markets
Abstract

Metadata only record The impacts of economic development on men and women varies greatly and often results in disadvantageous circumstances for women. Increased understanding of the 'work-life course' and gendered livelihoods can help to formulate more gender-specific and equally beneficial interventions related to economic and market growth. Over one hundred interviews conducted in the Trivandrum District, Kerala, India were used to help illustrate differential impacts of development, such as commercialization, by one's gender and livelihood strategy. It was found that women, for various reasons relating financial, social, and material capital to which they had access throughout their entire lives, were at a disadvantage in a market undergoing commercialization. This disadvantage through the work-life course must be fully understood in order for interventions to be truly successful for both genders.

Published
2004

16. Gendered livelihoods in diverse global contexts: an introduction

Author

Holly M. Hapke, Ann M. Oberhauser, and Jennifer L. Mandel

Subjects
Cultural Studies, Gender Studies, Arts and Humanities (miscellaneous), media_common.quotation_subject, Environmental ethics, Sociology, Ideology, Livelihood, Demography, Theme (narrative), media_common
Abstract

Gendered livelihoods encompass the material realities and ideological processes that shape and are shaped by economic strategies in diverse geographical locations. The articles in this theme issue ...

Published
2004

17. Cultivating Discourse: The Social Construction of Agricultural Legislation

Author

Holly M. Hapke and Deborah Dixon

Subjects
business.industry, media_common.quotation_subject, Geography, Planning and Development, Legislation, Consumption (sociology), Social constructionism, Ideal (ethics), Agrarian society, Agriculture, Political economy, Sociology, Social science, Relation (history of concept), business, Welfare, Earth-Surface Processes, media_common
Abstract

In this article we initiate a critical analysis of the discursive geographies from which U.S. agricultural legislation has been constructed. First, we refer to the geography of discourse, which consists of the production, dissemination, and consumption of ideas, concepts, theories, and understandings. Specifically, we trace the emergence and development of an American agrarian discourse, constituted from a wealth of ideas and theories concerning the place of farming in American society and the embodiment of these lines of thought in the agricultural legislation of the nineteenth and twentieth centuries. We highlight particular discursive sites and the establishment of expert groups and associated institutions, as well as time and place specific understandings of farmers and farming. The second dimension we draw out focuses on the semantic geography of discourse itself: It is through discourse that objects of debate—such as people and place—are demarcated and placed in relation to each other. In this case, farming and farmers have been understood in relation to a series of binaries (free/fettered, family/corporate, rural/urban, welfare/investment, safety/risk, individual/social, us/them), one side of which becomes valorized as “ideal” or the “norm.” We explore the semantic geography of agricultural legislation by focusing on one discursive site, namely the U.S. Senate, and the debates leading to the passage of the 1996 Freedom to Farm Bill.

Published
2003

20. A Woman's Place in the Crab Processing Industry of Eastern Carolina

Author

Deborah Dixon, Emily F. Selby, and Holly M. Hapke

Subjects
Cultural Studies, Gender Studies, Gerontology, White (horse), Geography, Arts and Humanities (miscellaneous), Migrant workers, Kinship, Socioeconomics, Demography
Abstract

Traditionally, most of the pickers used in the crab processing industry of rural Eastern Carolina have been women from the local area, both black and white, while the managerial staff has comprised white women related through kinship to the white, male crab house owners. In recent years, however, this recruitment strategy has changed. Following the lead of the regional poultry industry, the crab houses are now bringing in Mexican workers under the H2-B visa program. Unlike many of the Mexican migrant workers coming into the USA, the crab labor force is made up of women, about half of whom are married with children. This article provides a case study of the ensuing dual labor structure within the crab processing industry. Utilizing in-depth interviews with the employers and employees of the Luther Lewis and Son crab house, the authors ask: What are the contours of inclusiveness and exclusiveness within and without the crab house?

Published
2001

21. Gender, Work, and Household Survival in South Indian Fishing Communities: A Preliminary Analysis

Author

Holly M. Hapke

Subjects
Level data, media_common.quotation_subject, Geography, Planning and Development, Economic transformation, Fishing, Preliminary analysis, Geography, Work (electrical), Survival strategy, Ideology, Socioeconomics, Socioeconomic status, Earth-Surface Processes, Demography, media_common
Abstract

This article examines the interplay of gender, caste-religion, and household survival strategy formation among Christian and Muslim fisher folk in the south Indian state of Kerala. The methodology consisted of surveys of forty-one households in two villages in which data pertaining to male and female work patterns and other household level data were collected in the summer of 1999. My analysis demonstrates how particular ideologies of gender and work associated with different caste-religion communities influence the strategies individual households adopt. I discuss intersections between gender and caste-religion with other socioeconomic factors and illustrate the manner in which gender then gets reworked in particular ways in the course of economic transformation.

Published
2001

22. Measurement of the B0 lifetime and oscillation frequency using →ℓ decays

Author

G. Abbiendi, K. Ackerstaff, C. Ainsley, P.F. Åkesson, G. Alexander, J. Allison, K.J. Anderson, S. Arcelli, S. Asai, S.F. Ashby, D. Axen, G. Azuelos, I. Bailey, A.H. Ball, E. Barberio, R.J. Barlow, S. Baumann, T. Behnke, K.W. Bell, G. Bella, A. Bellerive, G. Benelli, S. Bentvelsen, S. Bethke, O. Biebel, I.J. Bloodworth, O. Boeriu, P. Bock, J. Böhme, D. Bonacorsi, M. Boutemeur, S. Braibant, P. Bright-Thomas, L. Brigliadori, R.M. Brown, H.J. Burckhart, J. Cammin, P. Capiluppi, R.K. Carnegie, A.A. Carter, J.R. Carter, C.Y. Chang, D.G. Charlton, P.E.L. Clarke, E. Clay, I. Cohen, O.C. Cooke, J. Couchman, C. Couyoumtzelis, R.L. Coxe, A. Csilling, M. Cuffiani, S. Dado, G.M. Dallavalle, S. Dallison, A. de Roeck, E. de Wolf, P. Dervan, K. Desch, B. Dienes, M.S. Dixit, M. Donkers, J. Dubbert, E. Duchovni, G. Duckeck, I.P. Duerdoth, P.G. Estabrooks, E. Etzion, F. Fabbri, M. Fanti, L. Feld, P. Ferrari, F. Fiedler, I. Fleck, M. Ford, A. Frey, A. Fürtjes, D.I. Futyan, P. Gagnon, J.W. Gary, G. Gaycken, C. Geich-Gimbel, G. Giacomelli, P. Giacomelli, D. Glenzinski, J. Goldberg, C. Grandi, K. Graham, E. Gross, J. Grunhaus, M. Gruwé, P.O. Günther, C. Hajdu, G.G. Hanson, M. Hansroul, M. Hapke, K. Harder, A. Harel, M. Harin-Dirac, A. Hauke, M. Hauschild, C.M. Hawkes, R. Hawkings, R.J. Hemingway, C. Hensel, G. Herten, R.D. Heuer, J.C. Hill, A. Hocker, K. Hoffman, R.J. Homer, A.K. Honma, D. Horváth, K.R. Hossain, R. Howard, P. Hüntemeyer, P. Igo-Kemenes, K. Ishii, F.R. Jacob, A. Jawahery, H. Jeremie, C.R. Jones, P. Jovanovic, T.R. Junk, N. Kanaya, J. Kanzaki, G. Karapetian, D. Karlen, V. Kartvelishvili, K. Kawagoe, T. Kawamoto, R.K. Keeler, R.G. Kellogg, B.W. Kennedy, D.H. Kim, K. Klein, A. Klier, S. Kluth, T. Kobayashi, M. Kobel, T.P. Kokott, S. Komamiya, R.V. Kowalewski, T. Kress, P. Krieger, J. von Krogh, T. Kuhl, M. Kupper, P. Kyberd, G.D. Lafferty, H. Landsman, D. Lanske, I. Lawson, J.G. Layter, A. Leins, D. Lellouch, J. Letts, L. Levinson, R. Liebisch, J. Lillich, B. List, C. Littlewood, A.W. Lloyd, S.L. Lloyd, F.K. Loebinger, G.D. Long, M.J. Losty, J. Lu, J. Ludwig, A. Macchiolo, A. Macpherson, W. Mader, S. Marcellini, T.E. Marchant, A.J. Martin, J.P. Martin, G. Martinez, T. Mashimo, P. Mättig, W.J. McDonald, J. McKenna, T.J. McMahon, R.A. McPherson, F. Meijers, P. Mendez-Lorenzo, W. Menges, F.S. Merritt, H. Mes, A. Michelini, S. Mihara, G. Mikenberg, D.J. Miller, W. Mohr, A. Montanari, T. Mori, K. Nagai, I. Nakamura, H.A. Neal, R. Nisius, S.W. O'Neale, F.G. Oakham, F. Odorici, H.O. Ogren, A. Oh, A. Okpara, M.J. Oreglia, S. Orito, G. Pásztor, J.R. Pater, G.N. Patrick, J. Patt, P. Pfeifenschneider, J.E. Pilcher, J. Pinfold, D.E. Plane, B. Poli, J. Polok, O. Pooth, M. Przybycień, A. Quadt, C. Rembser, P. Renkel, H. Rick, N. Rodning, J.M. Roney, S. Rosati, K. Roscoe, A.M. Rossi, Y. Rozen, K. Runge, O. Runolfsson, D.R. Rust, K. Sachs, T. Saeki, O. Sahr, E.K.G. Sarkisyan, C. Sbarra, A.D. Schaile, O. Schaile, P. Scharff-Hansen, M. Schröder, M. Schumacher, C. Schwick, W.G. Scott, R. Seuster, T.G. Shears, B.C. Shen, C.H. Shepherd-Themistocleous, P. Sherwood, G.P. Siroli, A. Skuja, A.M. Smith, G.A. Snow, R. Sobie, S. Söldner-Rembold, S. Spagnolo, M. Sproston, A. Stahl, K. Stephens, K. Stoll, D. Strom, R. Ströhmer, L. Stumpf, B. Surrow, S.D. Talbot, S. Tarem, R.J. Taylor, R. Teuscher, M. Thiergen, J. Thomas, M.A. Thomson, E. Torrence, S. Towers, D. Toya, T. Trefzger, I. Trigger, Z. Trócsányi, E. Tsur, M.F. Turner-Watson, I. Ueda, B. Vachon, P. Vannerem, M. Verzocchi, H. Voss, J. Vossebeld, D. Waller, C.P. Ward, D.R. Ward, P.M. Watkins, A.T. Watson, N.K. Watson, P.S. Wells, T. Wengler, N. Wermes, D. Wetterling, J.S. White, G.W. Wilson, J.A. Wilson, T.R. Wyatt, S. Yamashita, V. Zacek, and D. Zer-Zion

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Meson, 010308 nuclear & particles physics, Oscillation, 0103 physical sciences, Detector, 010306 general physics, 01 natural sciences
Abstract

The lifetime and oscillation frequency of the B0 meson has been measured using B0->D*+l-v decays recorded on the Z0 peak with the OPAL detector at LEP. The D*+ -> D0pi+ decays were reconstructed using an inclusive technique and the production flavour of the B0 mesons was determined using a combination of tags from the rest of the event. The results t_B0 = 1.541 +- 0.028 +- 0.023 ps, Dm_d = 0.497 +- 0.024 +- 0.025 ps-1 were obtained, where in each case the first error is statistical and the second systematic.

Published
2000

23. First measurement of the inclusive branching ratio of b hadrons to φ mesons in Z decays

Author

G. Abbiendi, K. Ackerstaff, C. Ainsley, P.F. Akesson, G. Alexander, J. Allison, K.J. Anderson, S. Arcelli, S. Asai, S.F. Ashby, D. Axen, G. Azuelos, I. Bailey, A.H. Ball, E. Barberio, R.J. Barlow, S. Baumann, T. Behnke, K.W. Bell, G. Bella, A. Bellerive, S. Bentvelsen, S. Bethke, O. Biebel, I.J. Bloodworth, P. Bock, J. Böhme, O. Boeriu, D. Bonacorsi, M. Boutemeur, S. Braibant, P. Bright-Thomas, L. Brigliadori, R.M. Brown, H.J. Burckhart, J. Cammin, P. Capiluppi, R.K. Carnegie, A.A. Carter, J.R. Carter, C.Y. Chang, D.G. Charlton, C. Ciocca, P.E.L. Clarke, E. Clay, I. Cohen, O.C. Cooke, J. Couchman, C. Couyoumtzelis, R.L. Coxe, M. Cuffiani, S. Dado, G.M. Dallavalle, S. Dallison, A. de Roeck, P. Dervan, K. Desch, B. Dienes, M.S. Dixit, M. Donkers, J. Dubbert, E. Duchovni, G. Duckeck, I.P. Duerdoth, P.G. Estabrooks, E. Etzion, F. Fabbri, M. Fanti, L. Feld, P. Ferrari, F. Fiedler, I. Fleck, M. Ford, A. Frey, A. Fürtjes, D.I. Futyan, P. Gagnon, J.W. Gary, G. Gaycken, C. Geich-Gimbel, G. Giacomelli, P. Giacomelli, D. Glenzinski, J. Goldberg, C. Grandi, K. Graham, E. Gross, J. Grunhaus, M. Gruwé, P.O. Günther, C. Hajdu, G.G. Hanson, M. Hansroul, M. Hapke, K. Harder, A. Harel, C.K. Hargrove, M. Harin-Dirac, A. Hauke, M. Hauschild, C.M. Hawkes, R. Hawkings, R.J. Hemingway, C. Hensel, G. Herten, R.D. Heuer, M.D. Hildreth, J.C. Hill, A. Hocker, K. Hoffman, R.J. Homer, A.K. Honma, D. Horváth, K.R. Hossain, R. Howard, P. Hüntemeyer, P. Igo-Kemenes, K. Ishii, F.R. Jacob, A. Jawahery, H. Jeremie, C.R. Jones, P. Jovanovic, T.R. Junk, N. Kanaya, J. Kanzaki, G. Karapetian, D. Karlen, V. Kartvelishvili, K. Kawagoe, T. Kawamoto, R.K. Keeler, R.G. Kellogg, B.W. Kennedy, D.H. Kim, K. Klein, A. Klier, T. Kobayashi, M. Kobel, T.P. Kokott, S. Komamiya, R.V. Kowalewski, T. Kress, P. Krieger, J. von Krogh, T. Kuhl, M. Kupper, P. Kyberd, G.D. Lafferty, H. Landsman, D. Lanske, I. Lawson, J.G. Layter, A. Leins, D. Lellouch, J. Letts, L. Levinson, R. Liebisch, J. Lillich, B. List, C. Littlewood, A.W. Lloyd, S.L. Lloyd, F.K. Loebinger, G.D. Long, M.J. Losty, J. Lu, J. Ludwig, A. Macchiolo, A. Macpherson, W. Mader, M. Mannelli, S. Marcellini, T.E. Marchant, A.J. Martin, J.P. Martin, G. Martinez, T. Mashimo, P. Mättig, W.J. McDonald, J. McKenna, T.J. McMahon, R.A. McPherson, F. Meijers, P. Mendez-Lorenzo, F.S. Merritt, H. Mes, A. Michelini, S. Mihara, G. Mikenberg, D.J. Miller, W. Mohr, A. Montanari, T. Mori, K. Nagai, I. Nakamura, H.A. Neal, R. Nisius, S.W. O'Neale, F.G. Oakham, F. Odorici, H.O. Ogren, A. Oh, A. Okpara, M.J. Oreglia, S. Orito, G. Pásztor, J.R. Pater, G.N. Patrick, J. Patt, P. Pfeifenschneider, J.E. Pilcher, J. Pinfold, D.E. Plane, B. Poli, J. Polok, O. Przybycień, A. Quadt, C. Rembser, H. Rick, S.A. Robins, N. Rodning, J.M. Roney, S. Rosati, K. Roscoe, A.M. Rossi, Y. Rozen, K. Runge, O. Runolfsson, D.R. Rust, K. Sachs, T. Saeki, O. Sahr, E.K.G. Sarkisyan, C. Sbarra, A.D. Schaile, O. Schaile, P. Scharff-Hansen, S. Schmitt, M. Schröder, M. Schumacher, C. Schwick, W.G. Scott, R. Seuster, T.G. Shears, B.C. Shen, C.H. Shepherd-Themistocleous, P. Sherwood, G.P. Siroli, A. Skuja, A.M. Smith, G.A. Snow, R. Sobie, S. Söldner-Rembold, S. Spagnolo, M. Sproston, A. Stahl, K. Stephens, K. Stoll, D. Strom, R. Ströhmer, B. Surrow, S.D. Talbot, S. Tarem, R.J. Taylor, R. Teuscher, M. Thiergen, J. Thomas, M.A. Thomson, E. Torrence, S. Towers, T. Trefzger, I. Trigger, Z. Trócsányi, E. Tsur, M.F. Turner-Watson, I. Ueda, P. Vannerem, M. Verzocchi, H. Voss, J. Vossebeld, D. Waller, C.P. Ward, D.R. Ward, P.M. Watkins, A.T. Watson, N.K. Watson, P.S. Wells, T. Wengler, N. Wermes, D. Wetterling, J.S. White, G.W. Wilson, J.A. Wilson, T.R. Wyatt, S. Yamashita, V. Zacek, and D. Zer-Zion

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Meson, Branching fraction, High Energy Physics::Phenomenology, Hadron, Detector, High Energy Physics::Experiment, Nuclear Experiment, Production rate
Abstract

The inclusive production rate of phi mesons from the decay of b hadrons produced in Z0 decays was measured to be Br(b->phi+X) = 0.0282+-0.0013(stat.)+-0.0019(syst.), using data collected by the OPAL detector at LEP.

Published
2000

24. Measurement of |Vcb| using decays

Author

G. Abbiendi, K. Ackerstaff, P.F. Akesson, G. Alexander, J. Allison, K.J. Anderson, S. Arcelli, S. Asai, S.F. Ashby, D. Axen, G. Azuelos, I. Bailey, A.H. Ball, E. Barberio, R.J. Barlow, J.R. Batley, S. Baumann, T. Behnke, K.W. Bell, G. Bella, A. Bellerive, S. Bentvelsen, S. Bethke, O. Biebel, A. Biguzzi, I.J. Bloodworth, P. Bock, J. Böhme, O. Boeriu, D. Bonacorsi, M. Boutemeur, S. Braibant, P. Bright-Thomas, L. Brigliadori, R.M. Brown, H.J. Burckhart, J. Cammin, P. Capiluppi, R.K. Carnegie, A.A. Carter, J.R. Carter, C.Y. Chang, D.G. Charlton, D. Chrisman, C. Ciocca, P.E.L. Clarke, E. Clay, I. Cohen, O.C. Cooke, J. Couchman, C. Couyoumtzelis, R.L. Coxe, M. Cuffiani, S. Dado, G.M. Dallavalle, S. Dallison, R. Davis, A. de Roeck, P. Dervan, K. Desch, B. Dienes, M.S. Dixit, M. Donkers, J. Dubbert, E. Duchovni, G. Duckeck, I.P. Duerdoth, P.G. Estabrooks, E. Etzion, F. Fabbri, A. Fanfani, M. Fanti, A.A. Faust, L. Feld, P. Ferrari, F. Fiedler, M. Fierro, I. Fleck, A. Frey, A. Fürtjes, D.I. Futyan, P. Gagnon, J.W. Gary, G. Gaycken, C. Geich-Gimbel, G. Giacomelli, P. Giacomelli, D.M. Gingrich, D. Glenzinski, J. Goldberg, W. Gorn, C. Grandi, K. Graham, E. Gross, J. Grunhaus, M. Gruwé, P.O. Günther, C. Hajdu, G.G. Hanson, M. Hansroul, M. Hapke, K. Harder, A. Harel, C.K. Hargrove, M. Harin-Dirac, A. Hauke, M. Hauschild, C.M. Hawkes, R. Hawkings, R.J. Hemingway, C. Hensel, G. Herten, R.D. Heuer, M.D. Hildreth, J.C. Hill, P.R. Hobson, A. Hocker, K. Hoffman, R.J. Homer, A.K. Honma, D. Horváth, K.R. Hossain, R. Howard, P. Hüntemeyer, P. Igo-Kemenes, D.C. Imrie, K. Ishii, F.R. Jacob, A. Jawahery, H. Jeremie, M. Jimack, C.R. Jones, P. Jovanovic, T.R. Junk, N. Kanaya, J. Kanzaki, G. Karapetian, D. Karlen, V. Kartvelishvili, K. Kawagoe, T. Kawamoto, P.I. Kayal, R.K. Keeler, R.G. Kellogg, B.W. Kennedy, D.H. Kim, K. Klein, A. Klier, T. Kobayashi, M. Kobel, T.P. Kokott, M. Kolrep, S. Komamiya, R.V. Kowalewski, T. Kress, P. Krieger, J. von Krogh, T. Kuhl, M. Kupper, P. Kyberd, G.D. Lafferty, H. Landsman, D. Lanske, I. Lawson, J.G. Layter, A. Leins, D. Lellouch, J. Letts, L. Levinson, R. Liebisch, J. Lillich, B. List, C. Littlewood, A.W. Lloyd, S.L. Lloyd, F.K. Loebinger, G.D. Long, M.J. Losty, J. Lu, J. Ludwig, A. Macchiolo, A. Macpherson, W. Mader, M. Mannelli, S. Marcellini, T.E. Marchant, A.J. Martin, J.P. Martin, G. Martinez, T. Mashimo, P. Mättig, W.J. McDonald, J. McKenna, T.J. McMahon, R.A. McPherson, F. Meijers, P. Mendez-Lorenzo, F.S. Merritt, H. Mes, I. Meyer, A. Michelini, S. Mihara, G. Mikenberg, D.J. Miller, W. Mohr, A. Montanari, T. Mori, K. Nagai, I. Nakamura, H.A. Neal, R. Nisius, S.W. O'Neale, F.G. Oakham, F. Odorici, H.O. Ogren, A. Okpara, M.J. Oreglia, S. Orito, G. Pásztor, J.R. Pater, G.N. Patrick, J. Patt, R. Perez-Ochoa, P. Pfeifenschneider, J.E. Pilcher, J. Pinfold, D.E. Plane, B. Poli, J. Polok, M. Przybycień, A. Quadt, C. Rembser, H. Rick, S.A. Robins, N. Rodning, J.M. Roney, S. Rosati, K. Roscoe, A.M. Rossi, Y. Rozen, K. Runge, O. Runolfsson, D.R. Rust, K. Sachs, T. Saeki, O. Sahr, W.M. Sang, E.K.G. Sarkisyan, C. Sbarra, A.D. Schaile, O. Schaile, P. Scharff-Hansen, S. Schmitt, A. Schöning, M. Schröder, M. Schumacher, C. Schwick, W.G. Scott, R. Seuster, T.G. Shears, B.C. Shen, C.H. Shepherd-Themistocleous, P. Sherwood, G.P. Siroli, A. Skuja, A.M. Smith, G.A. Snow, R. Sobie, S. Söldner-Rembold, S. Spagnolo, M. Sproston, A. Stahl, K. Stephens, K. Stoll, D. Strom, R. Ströhmer, B. Surrow, S.D. Talbot, S. Tarem, R.J. Taylor, R. Teuscher, M. Thiergen, J. Thomas, M.A. Thomson, E. Torrence, S. Towers, T. Trefzger, I. Trigger, Z. Trócsányi, E. Tsur, M.F. Turner-Watson, I. Ueda, R. Van Kooten, P. Vannerem, M. Verzocchi, H. Voss, D. Waller, C.P. Ward, D.R. Ward, P.M. Watkins, A.T. Watson, N.K. Watson, P.S. Wells, T. Wengler, N. Wermes, D. Wetterling, J.S. White, G.W. Wilson, J.A. Wilson, T.R. Wyatt, S. Yamashita, V. Zacek, and D. Zer-Zion

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, 010308 nuclear & particles physics, Branching fraction, Form factor (quantum field theory), Zero (complex analysis), Value (computer science), 01 natural sciences, Recoil, 0103 physical sciences, Heavy quark effective theory, Matrix element, 010306 general physics
Abstract

The magnitude of the Cabibbo-Kobayashi-Maskawa matrix element Vcb has been measured using B0 to D*l nu decays recorded on the Z0 peak using the OPAL detector at LEP. The D* to D0 pi+ decays were reconstructed both in the particular decay modes D0 to K- pi+ and D0 to K- pi+ pi- and via an inclusive technique. The product of |Vcb| and the decay form factor of the B0 to D* l nu transition at zero recoil F(1) was measured to be F(1)|Vcb| = (37.1+-1.0+-2.0)x10^-3, where the uncertainties are statistical and systematic respectively. By using Heavy Quark Effective Theory calculations for F(1), a value of |Vcb| = (40.7+-1.1+-2.2+-1.6)x 10^-3 was obtained, where the third error is due to theoretical uncertainties in the value of F(1). The branching ratio Br(B0 to D* l nu) was also measured to be (5.26+-0.20+-0.46)%.

Published
2000

25. Search for anomalous production of acoplanar di-lepton events in ${\rm e^+e^-}$ collisions at $\sqrt{s} =$ 183 and 189 GeV

Author

P. Ferrari, Randall Sobie, H. Mes, Naoko Kanaya, R. J. Hemingway, G. D. Lafferty, I. P. Duerdoth, S. Braibant, J. Lillich, Christopher Hawkes, German Martinez, K. Stephens, H. O. Ogren, B. W. Kennedy, P. Jovanovic, C. Littlewood, Christoph Geich-Gimbel, Gideon Bella, K. Stoll, Andris Skuja, S. Petzold, Austin Ball, Guenter Duckeck, A. A. Faust, P. Hüntemeyer, Daniel Lellouch, L. Brigliadori, H. J. Burckhart, Jacqueline Batley, Peter R Hobson, D. Zer-Zion, Takehiko Mori, Peter Krieger, Vakhtang Kartvelishvili, Tetsuro Mashimo, S. W. O'Neale, M. F. Turner-Watson, K. J. Anderson, Sachio Komamiya, A. Okpara, P. Mättig, T. J. McMahon, Richard Teuscher, R. Kowalewski, Erez Etzion, M. A. Thomson, A. T. Watson, Matthias Schröder, D. E. Plane, F. Fiedler, M. Thiergen, J. E. Conboy, A. Fürtjes, S. Arcelli, Alessandro Montanari, I. Meyer, C. Couyoumtzelis, T. P. Kokott, J. Dubbert, D. Waller, E. K. U. Gross, M. Verzocchi, W. Gorn, R. K. Carnegie, Shlomit Tarem, Lutz Feld, R. Van Kooten, T. Saeki, G. M. Dallavalle, Alessandra Fanfani, R. Davis, G. Gaycken, P. G. Bright-Thomas, J. A. Wilson, M. Sproston, C. R. Jones, J. Böhme, B. Surrow, M. Schumacher, M. Boutemeur, F. S. Merritt, Gideon Alexander, Thomas E Marchant, Paolo Capiluppi, Michael Hildreth, Achim Stahl, I. Trigger, Stefan Schmitt, Alain Bellerive, M. Kolrep, N. L. Rodning, T. Kuhl, Paul Kyberd, F. K. Loebinger, P. Dervan, S. Yamashita, P. Scharff-Hansen, B. Poli, F. Odorici, K. Graham, F. Wäckerle, D. R. Ward, Tara Shears, H. Voss, R. J. Barlow, Georges Azuelos, Ivor Fleck, Richard Nisius, B. List, Ekg Sarkisyan, D. M. Gingrich, P. Igo-Kemenes, E. Tsur, Ehud Duchovni, D. Axen, A. Jawahery, Oana Elena Vickey Boeriu, J. Grunhaus, J. Bechtluft, J. A. McKenna, D. J. Miller, Joleen Pater, K. W. Bell, J. Goldberg, Dave Charlton, Marco Cuffiani, K. Ishii, H. Jeremie, S. B. Anderson, Shoji Asai, M. Jimack, A. M. Smith, K. Hoffman, A. Klier, A. Michelini, Juergen Thomas, M. Przybycień, H. A. Neal, M. Fanti, T. Kress, J. C. Hill, J. M. Roney, S. Spagnolo, A. M. Rossi, W. R. Gibson, W. J. McDonald, B. C. Shen, A. A. Carter, I. J. Bloodworth, M. Donkers, Kiyotomo Kawagoe, K. Harder, Siegfried Bethke, D. Liu, A. K. Honma, Robert McPherson, Paolo Giacomelli, T. Kobayashi, Stan Bentvelsen, O. Schaile, M. Hansroul, Koichi Nagai, John Allison, W. G. Scott, J. Schieck, R. Hawkings, I. Nakamura, H. Landsman, Peter Sherwood, I. Cohen, R. D. Heuer, Christoph Rembser, James Pinfold, S. Robertson, Yoram Rozen, W. Mohr, Fabrizio Fabbri, A. Frey, R. Perez-Ochoa, R. Seuster, Giovanni Abbiendi, A. J. Martin, Claudia Ciocca, M. Harin-Dirac, S. A. Robins, R. L. Coxe, T. Trefzger, R. J. Homer, R. G. Kellogg, Junichi Kanzaki, J. Polok, R. M. Brown, D. Karlen, D. R. Rust, P. Mendez-Lorenzo, F. G. Oakham, R. Liebisch, K. Ackerstaff, Alexander Wagner, A. Macchiolo, J. Ludwig, A. Hocker, Daniele Bonacorsi, K. Runge, P. Bock, Lorne Levinson, Csaba Hajdu, D. Glenzinski, Dezso Horvath, M. J. Losty, Stefano Marcellini, E. L. Barberio, D. Chrisman, G. D. Long, V. Zacek, K. R. Hossain, W. M. Sang, J. Couchman, W. Mader, O. C. Cooke, P. Pfeifenschneider, J. W. Gary, Marcello Mannelli, C. K. Hargrove, Stephen Lloyd, J. Patt, D. C. Imrie, André Schöning, C. H. Shepherd-Themistocleous, J. von Krogh, O. Sahr, C. Sbarra, F. R. Jacob, G. P. Siroli, M. Gruwé, D. Wetterling, Christoph Schwick, K. Roscoe, P. Gagnon, S. Baumann, E. Torrence, Zoltan Laszlo Trocsanyi, E. Clay, Dong Hee Kim, J. Lauber, E. A. Mckigney, S. D. Talbot, T. Behnke, Satoshi Mihara, T. R. Junk, D. Lanske, D. I. Futyan, P. S. Wells, Terry Richard Wyatt, O. Runolfsson, P. G. Estabrooks, R. K. Keeler, N. K. Watson, Arnulf Quadt, P. M. Watkins, Claudio Grandi, J. S. White, M. Fierro, S. Rosati, A. Harel, Ikuo Ueda, D. M. Strom, A. D. Schaile, Gabriella Pasztor, J. Lu, P. Vannerem, G. A. Snow, C. P. Ward, Raimund Ströhmer, S. Söldner-Rembold, P. Poffenberger, Beatrix Dienes, J. Letts, C. Y. Chang, P. Taras, A. Macpherson, K. Sachs, Shlomo Dado, Giora Mikenberg, Klaus Desch, S. F. Ashby, R. Howard, Otmar Biebel, P. I. Kayal, Norbert Wermes, Sherry Towers, T. Kawamoto, S. Orito, S. Betts, M. Hapke, M. J. Oreglia, Gregor Herten, J. E. Pilcher, A. W. Lloyd, G. W. Wilson, M. Hauschild, S.J. Dallison, J. R. Carter, G. N. Patrick, A. Biguzzi, J. G. Layter, P. E.L. Clarke, J. P. Martin, S. De Jong, H. Rick, G. G. Hanson, G. Giacomelli, I. Lawson, A. De Roeck, M. Kobel, M. S. Dixit, and Frans Meijers

Subjects
Physics, Particle physics, Physics and Astronomy (miscellaneous), Branching fraction, Electron–positron annihilation, High Energy Physics::Phenomenology, Standard Model, Nuclear physics, Chargino, Neutralino, Higgs boson, High Energy Physics::Experiment, Nuclear Experiment, Engineering (miscellaneous), Minimal Supersymmetric Standard Model, Lepton
Abstract

A selection of di-lepton events with significant missing transverse momentum has been performed using a total data sample of 237.4 pb-1 at e+e- centre-of-rnass energies of approximately 183 GeV and 189 GeV. The observed numbers of events - 78 at 183 GeV and 301 at 189 GeV - are consistent with the numbers expected from Standard Model processes, which arise predominantly from W+W- production with both W bosons decaying leptonically. This topology is also an experimental signature for the pair production of new particles that decay to a charged lepton accompanied by one or more invisible particles. Discrimination techniques are described that optimise the sensitivity to particular new physics channels. No evidence for new phenomena is apparent. Upper limits on the production cross-section times branching ratio squared for sleptons and for leptonically decaying charginos and charged Higgs are presented in a manner intended to minimise the number of model assumptions. Assuming a 100% branching ratio for the decay l±R → l±χ01, where χ01 is the lightest neutralino, we exclude at 95% CL: right-handed smuons with masses below 82.3 GeV for mμ- - mχ01 > 3 GeV and right-handed staus with masses below 81.0 GeV for mτ- -mχ01 > 8 GeV. Right-handed selectrons are excluded at 95% CL for masses below 87.1 GeV for mẽ - mχ01 > 5 GeV, within the framework of the Minimal Supersymmetric Standard Model assuming μ, < - 100 GeV and tan β= 1.5. Charged Higgs bosons, H±, are excluded at 95% CL for masses below 82.8 GeV, assuming a 100% branching ratio for the decay H± → τ ± vτ.

Published
2000

26. A study of parton fragmentation in hadronic Z $^0$ decays using $\Lambda\bar\Lambda$ correlations

Author

B. Nellen, H. G. Evans, I. Cohen, Tara Shears, Christoph Rembser, C. Hartmann, D. E. Plane, T. J. McMahon, C. Couyoumtzelis, Stephen Hillier, G. Gaycken, P. G. Bright-Thomas, J. Dubbert, G. M. Dallavalle, S. A. Robins, R. K. Carnegie, M. Schumacher, M. Herndon, M. Bobinski, R. Liebisch, K. Stoll, P. G. Estabrooks, R. K. Keeler, J. A. Wilson, J. Böhme, Andris Skuja, K. Ackerstaff, Matthias Schröder, M. Thiergen, Gregor Herten, N. K. Watson, Dave Charlton, S. Petzold, P. M. Watkins, D. Lazic, A. Macpherson, M. Fierro, Randall Sobie, G. D. Lafferty, A. J. Martin, F. Odorici, Tetsuro Mashimo, S. R. Lautenschlager, J. Grunhaus, W. Mader, Erez Etzion, C. K. Hargrove, S. Betts, M. Hapke, S. Yamashita, J. E. Pilcher, Stefan Kluth, Shlomit Tarem, Stefan Schmitt, K. Roscoe, H. A. Neal, R. Bürgin, B. Surrow, C. Y. Chang, D. R. Rust, A. W. Lloyd, P. Igo-Kemenes, Georges Azuelos, P. E.L. Clarke, O. Runolfsson, A. D. Schaile, Gabriella Pasztor, E. Tsur, P. Vannerem, M. J. Oreglia, Klaus Kurt Desch, G. W. Wilson, W. Gorn, K. Ishii, H. Jeremie, M. Hauschild, C. Markopoulos, John Allison, J. Lauber, G. Yekutieli, S. Baumann, M. Przybycień, Guenter Duckeck, Sachio Komamiya, A. T. Watson, A. A. Carter, R. Howard, M. Verzocchi, K. W. Bell, P. Taras, Ron Folman, A. M. Lee, E. von Törne, E. A. Mckigney, E. Torrence, Claudio Grandi, J. S. White, J. Pálinkás, T. P. Kokott, G. A. Snow, C. P. Ward, J. P. Martin, J. R. Carter, S. Söldner-Rembold, G. N. Patrick, R. Mir, R. Hawkings, Otmar Biebel, E. Clay, Shoji Asai, Gideon Bella, Ekg Sarkisyan, T. Saeki, R. Davis, J. C. Hill, J. Letts, M. Fanti, O. Schaile, H. J. Burckhart, Daniel Lellouch, D. I. Futyan, Jacqueline Batley, P. I. Kayal, Takehiko Mori, H. Mes, James Pinfold, R. Perez-Ochoa, R. Seuster, Giovanni Abbiendi, S. De Jong, Claire Shepherd-Themistocleous, S. Robertson, Daniele Bonacorsi, S. B. Anderson, K. Sachs, Shlomo Dado, I. P. Duerdoth, S. Braibant, Norbert Wermes, Sherry Towers, T. Kawamoto, W. J. McDonald, W. R. Gibson, B. C. Shen, Robert McPherson, M. Boutemeur, F. S. Merritt, D. M. Strom, P. Mättig, J. Gascon, S. Orito, K. Harder, F. G. Oakham, B. Schmitt, E. L. Barberio, R. E. Schmitz, R. D. Heuer, Fabrizio Fabbri, Sven Menke, D. Lanske, Siegfried Bethke, D. Liu, Giora Mikenberg, S. F. Ashby, H. Rick, V. Zacek, R. Van Kooten, Stan Bentvelsen, J. von Krogh, P. Hüntemeyer, Raimund Ströhmer, R. J. Hemingway, A. A. Faust, A. K. Honma, W. G. Scott, S. D. Talbot, J. W. Gary, C. R. Jones, D. S. Koetke, R. M. Brown, Lorne Levinson, M. F. Turner-Watson, M. Gruwé, L. A. del Pozo, Marcello Mannelli, Peter R Hobson, I. Nakamura, B. W. Kennedy, P. Jovanovic, D. M. Gingrich, P. Scharff-Hansen, J. Bechtluft, Richard Teuscher, I. J. Bloodworth, D. Zer-Zion, A. S. Turcot, F. Fiedler, P. Poffenberger, J. A. McKenna, T. R. Junk, D. Eatough, Austin Ball, Peter Krieger, A. Macchiolo, A. M. Smith, P. S. Wells, D. Glenzinski, Dezso Horvath, M. J. Losty, R. G. Kellogg, G. G. Hanson, Jean-Arcady Meyer, Terry Richard Wyatt, C. M. Hawkes, Yoram Rozen, M. Kolrep, T. Behnke, R. Bartoldus, Alessandro Montanari, T. Kuhl, H. O. Ogren, J. Polok, G. Giacomelli, I. Lawson, Richard Nisius, Christoph Geich-Gimbel, D. Karlen, A. De Roeck, M. Kobel, O. C. Cooke, Beatrix Dienes, B. List, Marco Cuffiani, P. Pfeifenschneider, M. S. Dixit, Frans Meijers, Vakhtang Kartvelishvili, J. E. Conboy, A. Fürtjes, P. Gagnon, Stefano Marcellini, L. Brigliadori, N. Altekamp, H. Voss, R. J. Barlow, A. Biguzzi, D. J. Miller, J. Patt, J. G. Layter, A. Sittler, Zoltan Laszlo Trocsanyi, André Schöning, O. Sahr, W. M. Sang, S. W. O'Neale, K. J. Anderson, S. D. Bird, D. Axen, A. Jawahery, Peter Sherwood, Alexander Wagner, J. Ludwig, K. Runge, P. Bock, Paolo Giacomelli, C. Sbarra, F. R. Jacob, M. Hansroul, Paul Kyberd, F. K. Loebinger, J. Steuerer, Ivor Fleck, C. Burgard, Joleen Pater, A. Klier, R. J. Homer, Satoshi Mihara, Kiyotomo Kawagoe, Achim Stahl, K. R. Hossain, D. C. Imrie, G. P. Siroli, K. Stephens, Christoph Schwick, C. Littlewood, V. Gibson, I. Trigger, F. Scharf, German Martinez, D. R. Ward, T. Kress, J. M. Roney, Ehud Duchovni, Koichi Nagai, J. Schieck, W. Mohr, M. Jimack, M. A. Thomson, A. Michelini, Claudia Ciocca, F. Wöckerle, E. K. U. Gross, M. Sproston, S. M. Gascon-Shotkin, Satoshi Tanaka, T. Kobayashi, A. M. Rossi, R. L. Coxe, A. Hocker, D. Chrisman, G. D. Long, Volker Blobel, Michael Hildreth, Alain Bellerive, Stephen Lloyd, N. L. Rodning, R. Kowalewski, S. Arcelli, Gideon Alexander, Paolo Capiluppi, and J. Goldberg

Subjects
Physics, Particle physics, Physics and Astronomy (miscellaneous), Electron–positron annihilation, Hadron, Hyperon, Parton, Lambda, Lambda baryon, Nuclear physics, Baryon, High Energy Physics::Experiment, Rapidity, Engineering (miscellaneous)
Abstract

The correlated production of \(\Lambda\) and \(\bar\Lambda\) baryons has been studied using 4.3 million multihadronic \({\rm Z}^0\) decays recorded with the Opal detector at Lep. Lambda pairs were investigated in the full data sample and for the first time also in 2-jet and 3-jet events selected with the \(k_\perp\) algorithm. The distributions of rapidity differences from correlated \(\Lambda\bar\Lambda\) pairs exhibit short-range, local correlations and prove to be a sensitive tool to test models, particularly for 2-jet events. The Jetset model describes the data best but some extra parameter tuning is needed to improve agreement with the experimental results in the rates and the rapidity spectra simultaneously. The recently developed modification of Jetset, the MOdified Popcorn Scenarium (Mops), and also Herwig do not give satisfactory results. This study of di-lambda production in 2- and 3-jet events supports the short-range compensation of quantum numbers.

Published
2000

27. Z boson pair production in e+e− collisions at and 189 GeV

Author

G. Abbiendi, K. Ackerstaff, P.F. Akesson, G. Alexander, J. Allison, K.J. Anderson, S. Arcelli, S. Asai, S.F. Ashby, D. Axen, G. Azuelos, I. Bailey, A.H. Ball, E. Barberio, R.J. Barlow, J.R. Batley, S. Baumann, T. Behnke, K.W. Bell, G. Bella, A. Bellerive, S. Bentvelsen, S. Bethke, O. Biebel, A. Biguzzi, I.J. Bloodworth, P. Bock, J. Böhme, O. Boeriu, D. Bonacorsi, M. Boutemeur, S. Braibant, P. Bright-Thomas, L. Brigliadori, R.M. Brown, H.J. Burckhart, J. Cammin, P. Capiluppi, R.K. Carnegie, A.A. Carter, J.R. Carter, C.Y. Chang, D.G. Charlton, D. Chrisman, C. Ciocca, P.E.L. Clarke, E. Clay, I. Cohen, O.C. Cooke, J. Couchman, C. Couyoumtzelis, R.L. Coxe, M. Cuffiani, S. Dado, G.M. Dallavalle, S. Dallison, R. Davis, A. de Roeck, P. Dervan, K. Desch, B. Dienes, M.S. Dixit, M. Donkers, J. Dubbert, E. Duchovni, G. Duckeck, I.P. Duerdoth, P.G. Estabrooks, E. Etzion, F. Fabbri, A. Fanfani, M. Fanti, A.A. Faust, L. Feld, P. Ferrari, F. Fiedler, M. Fierro, I. Fleck, A. Frey, A. Fürtjes, D.I. Futyan, P. Gagnon, J.W. Gary, G. Gaycken, C. Geich-Gimbel, G. Giacomelli, P. Giacomelli, D.M. Gingrich, D. Glenzinski, J. Goldberg, W. Gorn, C. Grandi, K. Graham, E. Gross, J. Grunhaus, M. Gruwé, P.O. Günther, C. Hajdu, G.G. Hanson, M. Hansroul, M. Hapke, K. Harder, A. Harel, C.K. Hargrove, M. Harin-Dirac, A. Hauke, M. Hauschild, C.M. Hawkes, R. Hawkings, R.J. Hemingway, C. Hensel, G. Herten, R.D. Heuer, M.D. Hildreth, J.C. Hill, P.R. Hobson, A. Hocker, K. Hoffman, R.J. Homer, A.K. Honma, D. Horváth, K.R. Hossain, R. Howard, P. Hüntemeyer, P. Igo-Kemenes, D.C. Imrie, K. Ishii, F.R. Jacob, A. Jawahery, H. Jeremie, M. Jimack, C.R. Jones, P. Jovanovic, T.R. Junk, N. Kanaya, J. Kanzaki, G. Karapetian, D. Karlen, V. Kartvelishvili, K. Kawagoe, T. Kawamoto, P.I. Kayal, R.K. Keeler, R.G. Kellogg, B.W. Kennedy, D.H. Kim, K. Klein, A. Klier, T. Kobayashi, M. Kobel, T.P. Kokott, M. Kolrep, S. Komamiya, R.V. Kowalewski, T. Kress, P. Krieger, J. von Krogh, T. Kuhl, M. Kupper, P. Kyberd, G.D. Lafferty, H. Landsman, D. Lanske, I. Lawson, J.G. Layter, A. Leins, D. Lellouch, J. Letts, L. Levinson, R. Liebisch, J. Lillich, B. List, C. Littlewood, A.W. Lloyd, S.L. Lloyd, F.K. Loebinger, G.D. Long, M.J. Losty, J. Lu, J. Ludwig, A. Macchiolo, A. Macpherson, W. Mader, M. Mannelli, S. Marcellini, T.E. Marchant, A.J. Martin, J.P. Martin, G. Martinez, T. Mashimo, P. Mättig, W.J. McDonald, J. McKenna, T.J. McMahon, R.A. McPherson, F. Meijers, P. Mendez-Lorenzo, F.S. Merritt, H. Mes, I. Meyer, A. Michelini, S. Mihara, G. Mikenberg, D.J. Miller, W. Mohr, A. Montanari, T. Mori, K. Nagai, I. Nakamura, H.A. Neal, R. Nisius, S.W. O'Neale, F.G. Oakham, F. Odorici, H.O. Ogren, A. Okpara, M.J. Oreglia, S. Orito, G. Pásztor, J.R. Pater, G.N. Patrick, J. Patt, R. Perez-Ochoa, P. Pfeifenschneider, J.E. Pilcher, J. Pinfold, D.E. Plane, B. Poli, J. Polok, M. Przybycień, A. Quadt, C. Rembser, H. Rick, S.A. Robins, N. Rodning, J.M. Roney, S. Rosati, K. Roscoe, A.M. Rossi, Y. Rozen, K. Runge, O. Runolfsson, D.R. Rust, K. Sachs, T. Saeki, O. Sahr, W.M. Sang, E.K.G. Sarkisyan, C. Sbarra, A.D. Schaile, O. Schaile, P. Scharff-Hansen, S. Schmitt, A. Schöning, M. Schröder, M. Schumacher, C. Schwick, W.G. Scott, R. Seuster, T.G. Shears, B.C. Shen, C.H. Shepherd-Themistocleous, P. Sherwood, G.P. Siroli, A. Skuja, A.M. Smith, G.A. Snow, R. Sobie, S. Söldner-Rembold, S. Spagnolo, M. Sproston, A. Stahl, K. Stephens, K. Stoll, D. Strom, R. Ströhmer, B. Surrow, S.D. Talbot, S. Tarem, R.J. Taylor, R. Teuscher, M. Thiergen, J. Thomas, M.A. Thomson, E. Torrence, S. Towers, T. Trefzger, I. Trigger, Z. Trócsányi, E. Tsur, M.F. Turner-Watson, I. Ueda, R. Van Kooten, P. Vannerem, M. Verzocchi, H. Voss, D. Waller, C.P. Ward, D.R. Ward, P.M. Watkins, A.T. Watson, N.K. Watson, P.S. Wells, T. Wengler, N. Wermes, D. Wetterling, J.S. White, G.W. Wilson, J.A. Wilson, T.R. Wyatt, S. Yamashita, V. Zacek, and D. Zer-Zion

Subjects
Quark, Physics, Nuclear and High Energy Physics, Particle physics, Annihilation, 010308 nuclear & particles physics, State (functional analysis), 01 natural sciences, Standard Model, Pair production, 0103 physical sciences, High Energy Physics::Experiment, Nuclear Experiment, 010303 astronomy & astrophysics, Lepton
Abstract

A study of Z boson pair production in e+e- annihilation at center-of-mass energies near 183 GeV and 189 GeV is reported. Final states containing only leptons, (l+l-l+l- and l+l-nu nubar), quark and lepton pairs, (q qbar l+l-, q qbar nu nubar) and the all-hadronic final state (q qbar q qbar) are considered. In all states with at least one Z boson decaying hadronically, q qbar and b bbar final states are considered separately using lifetime and event-shape tags, thereby improving the cross-section measurement. At sqrt(s) = 189 GeV the Z-pair cross section was measured to be 0.80 (+0.14-0.13, stat.) (+0.06-0.05, syst.) pb, consistent with the Standard Model prediction. At sqrt(s) = 183 GeV the 95% C.L. upper limit is 0.55 pb. Limits on anomalous ZZgamma and ZZZ couplings are derived.

Published
2000

28. A study of $\mathrm{B_s^0}$ meson oscillation using hadronic $\mathrm Z^0$ decays containing leptons

Author

H. O. Ogren, Erez Etzion, Christoph Geich-Gimbel, Shlomit Tarem, Sachio Komamiya, D. Axen, S. Yamashita, A. T. Watson, A. Jawahery, B. Surrow, Richard Teuscher, P. Igo-Kemenes, Vakhtang Kartvelishvili, F. Fiedler, A. Biguzzi, J. E. Conboy, A. Fürtjes, J. G. Layter, K. Ishii, H. Jeremie, Peter Sherwood, Daniele Bonacorsi, J. von Krogh, M. Gruwé, D. Wetterling, T. P. Kokott, T. Saeki, Lutz Feld, Kiyotomo Kawagoe, O. C. Cooke, Alexander Wagner, A. Macchiolo, W. R. Gibson, P. Pfeifenschneider, T. J. McMahon, C. Couyoumtzelis, S. Betts, A. Macpherson, J. Dubbert, J. Ludwig, M. Hapke, K. Harder, S. A. Robins, R. Liebisch, K. Ackerstaff, J. Letts, R. K. Carnegie, G. Gaycken, P. G. Bright-Thomas, J. A. Wilson, J. Böhme, Raimund Ströhmer, M. Kolrep, Alessandra Fanfani, R. Davis, S. Baumann, K. Runge, P. Bock, M. Przybycień, T. Kress, E. A. Mckigney, A. A. Carter, I. J. Bloodworth, J. Patt, André Schöning, O. Schaile, W. J. McDonald, Giovanni Abbiendi, M. Schumacher, Matthias Schröder, B. C. Shen, R. J. Hemingway, M. A. Thomson, J. Lauber, M. Boutemeur, F. S. Merritt, O. Sahr, Klaus Desch, P. E.L. Clarke, R. Howard, S. Robertson, P. Poffenberger, Siegfried Bethke, D. Liu, A. K. Honma, K. R. Hossain, C. H. Shepherd-Themistocleous, K. Sachs, Christopher Hawkes, W. M. Sang, S. B. Anderson, Shlomo Dado, J. Grunhaus, E. K. U. Gross, R. L. Coxe, M. Thiergen, F. Odorici, W. G. Scott, Yoram Rozen, J. P. Martin, B. W. Kennedy, T. Kuhl, S. De Jong, I. Nakamura, Richard Nisius, J. Goldberg, J. Bechtluft, M. Sproston, P. Jovanovic, M. J. Oreglia, Stan Bentvelsen, Austin Ball, K. Stoll, S. D. Talbot, R. M. Brown, Lorne Levinson, Andris Skuja, Peter Krieger, B. List, H. Rick, Marco Cuffiani, P. Mendez-Lorenzo, Junichi Kanzaki, J. Polok, D. I. Futyan, Gregor Herten, K. Hoffman, Giora Mikenberg, S. F. Ashby, D. Glenzinski, Paolo Giacomelli, D. Karlen, T. Behnke, R. D. Heuer, Alessandro Montanari, Daniel Lellouch, T. R. Junk, P. S. Wells, M. Hansroul, Beatrix Dienes, A. Hocker, J. A. McKenna, I. Cohen, S. Petzold, Juergen Thomas, Tetsuro Mashimo, M. F. Turner-Watson, A. D. Schaile, Randall Sobie, G. D. Lafferty, R. Hawkings, Christoph Rembser, Dezso Horvath, M. J. Losty, Takehiko Mori, A. Okpara, Terry Richard Wyatt, P. Mättig, G. D. Long, G. G. Hanson, C. Y. Chang, Gabriella Pasztor, P. Gagnon, H. Landsman, J. M. Roney, M. Verzocchi, J. E. Pilcher, H. Mes, P. G. Estabrooks, R. K. Keeler, N. K. Watson, M. Harin-Dirac, P. Vannerem, G. A. Snow, C. P. Ward, D. C. Imrie, R. J. Homer, G. Giacomelli, I. Lawson, A. De Roeck, M. Kobel, Arnulf Quadt, Naoko Kanaya, P. M. Watkins, Guenter Duckeck, A. Sittler, Zoltan Laszlo Trocsanyi, I. P. Duerdoth, S. Braibant, F. G. Oakham, P. Taras, Dong Hee Kim, Koichi Nagai, J. Schieck, C. Sbarra, F. R. Jacob, Stefan Schmitt, G. P. Siroli, S. Söldner-Rembold, W. Gorn, J. R. Carter, G. N. Patrick, E. L. Barberio, A. J. Martin, M. S. Dixit, Stephen Lloyd, Frans Meijers, Satoshi Mihara, P. Hüntemeyer, Christoph Schwick, K. Roscoe, W. Mohr, John Allison, Otmar Biebel, Georges Azuelos, E. Tsur, Shoji Asai, P. Scharff-Hansen, A. A. Faust, Achim Stahl, O. Runolfsson, K. W. Bell, N. Altekamp, H. Voss, A. W. Lloyd, E. Torrence, R. J. Barlow, D. J. Miller, J. Couchman, W. Mader, Ehud Duchovni, A. M. Smith, R. G. Kellogg, K. Stephens, J. C. Hill, E. Clay, C. K. Hargrove, K. Graham, G. W. Wilson, M. Jimack, Csaba Hajdu, S. Spagnolo, C. Littlewood, Tara Shears, P. I. Kayal, Claudio Grandi, J. S. White, Stefano Marcellini, M. Hauschild, German Martinez, Ekg Sarkisyan, James Pinfold, L. Brigliadori, R. Perez-Ochoa, R. Seuster, V. Gibson, A. Michelini, Norbert Wermes, Sherry Towers, D. E. Plane, T. Kawamoto, D. Lanske, V. Zacek, Paul Kyberd, F. K. Loebinger, I. Trigger, T. Kobayashi, J. W. Gary, J. Steuerer, Ivor Fleck, D. R. Ward, S. Orito, G. M. Dallavalle, Marcello Mannelli, Joleen Pater, A. Klier, H. A. Neal, M. Fierro, R. Kowalewski, S. W. O'Neale, S. Arcelli, K. J. Anderson, Gideon Alexander, Paolo Capiluppi, Gideon Bella, H. J. Burckhart, Jacqueline Batley, C. R. Jones, M. Fanti, Peter R Hobson, D. Zer-Zion, Robert McPherson, Fabrizio Fabbri, A. Frey, R. Van Kooten, Claudia Ciocca, F. Wäckerle, D. M. Gingrich, A. M. Rossi, Michael Hildreth, Alain Bellerive, N. L. Rodning, P. Dervan, B. Poli, D. R. Rust, S. Rosati, A. Harel, Ikuo Ueda, D. M. Strom, and J. Lu

Subjects
Physics, Particle physics, Physics and Astronomy (miscellaneous), Meson, Oscillation, Electron–positron annihilation, High Energy Physics::Phenomenology, Hadron, Charge (physics), Jet (particle physics), Nuclear physics, High Energy Physics::Experiment, Production (computer science), Engineering (miscellaneous), Lepton
Abstract

A sample of \({\rm Z}^0\) decays containing b-flavoured hadrons is tagged using leptons, and events having precise proper time measurements are selected. These events are used to study \({\rm B}^0_{\rm s}\) oscillations. The flavour (b or \(\rm \bar{b}\)) at decay is determined from the lepton charge while the flavour at production is determined from jet charge or the charge of a second lepton, where available. The experiment was not able to resolve the oscillatory behaviour, and we deduce that the \({\rm B}^0_{\rm s}\) oscillation frequency \(\Delta m_{\rm s} > 5.2\) ps\(^{-1}\) at the 95% confidence level.

Published
1999

29. Intermittency and correlations in hadronic Z $^0$ decays

Author

K. Stephens, M. Schumacher, P. G. Estabrooks, F. Odorici, N. K. Watson, D. R. Rust, C. Littlewood, H. A. Neal, Otmar Biebel, P. Scharff-Hansen, P. M. Watkins, K. Hoffman, V. Gibson, Claire Shepherd-Themistocleous, A. M. Lee, J. Goldberg, Erez Etzion, Shlomit Tarem, B. Surrow, G. G. Hanson, Richard Teuscher, A. S. Turcot, N. Altekamp, H. Voss, A. Macpherson, H. O. Ogren, Christoph Geich-Gimbel, I. Trigger, F. Fiedler, Richard Keeler, D. R. Ward, A. M. Smith, P. I. Kayal, K. Stoll, G. Giacomelli, S. Yamashita, I. Lawson, R. J. Barlow, D. J. Miller, I. Cohen, Christoph Rembser, H. Mes, I. P. Duerdoth, S. Braibant, D. Axen, A. Jawahery, T. J. McMahon, A. De Roeck, M. Kobel, P. Igo-Kemenes, M. Hoch, K. Ishii, H. Jeremie, Dave Charlton, C. Couyoumtzelis, M. Fanti, S. A. Robins, M. S. Dixit, O. C. Cooke, S. Spagnolo, Andris Skuja, S. Petzold, Tetsuro Mashimo, A. A. Faust, Peter Sherwood, Alexander Wagner, R. Liebisch, K. Ackerstaff, Norbert Wermes, Sherry Towers, T. Kawamoto, Frans Meijers, J. Dubbert, P. Pfeifenschneider, M. F. Turner-Watson, I. J. Bloodworth, Vakhtang Kartvelishvili, P. Hüntemeyer, R. K. Carnegie, A. J. Martin, R. Kowalewski, J. E. Conboy, A. Fürtjes, R. Howard, P. E.L. Clarke, J. Ludwig, K. Runge, R. Mir, P. Bock, M. Kolrep, J. Patt, R. Hawkings, Satoshi Mihara, Paul Kyberd, S. Orito, S. Arcelli, M. Herndon, F. K. Loebinger, S. Baumann, J. A. Wilson, J. Böhme, Michael Hildreth, Alain Bellerive, André Schöning, Robert McPherson, J. P. Martin, O. Sahr, H. Landsman, P. Gagnon, J. Steuerer, Ivor Fleck, O. Schaile, S. Robertson, R. D. Heuer, E. A. Mckigney, Gideon Alexander, N. L. Rodning, W. Gorn, W. Mader, Paolo Capiluppi, Joleen Pater, P. Dervan, B. Poli, Peter R Hobson, S. De Jong, A. Klier, F. G. Oakham, A. Sittler, D. Zer-Zion, D. C. Imrie, C. K. Hargrove, S. Betts, Yoram Rozen, S. B. Anderson, Matthias Schröder, W. R. Gibson, Gregor Herten, R. L. Coxe, Georges Azuelos, K. Harder, Fabrizio Fabbri, A. Frey, H. Rick, E. L. Barberio, D. Lazic, A. Macchiolo, Zoltan Laszlo Trocsanyi, Dong Hee Kim, M. Hapke, A. Hocker, M. Thiergen, Gideon Bella, H. J. Burckhart, Jacqueline Batley, D. Chrisman, G. D. Long, E. Tsur, D. I. Futyan, Volker Blobel, R. J. Hemingway, T. Kuhl, J. Lauber, R. Van Kooten, S. M. Gascon-Shotkin, Paolo Giacomelli, Sven Menke, Christopher Hawkes, G. Yekutieli, M. Verzocchi, K. W. Bell, J. Pálinkás, J. Grunhaus, G. P. Siroli, M. Przybycień, Junichi Kanzaki, J. Polok, M. Boutemeur, F. S. Merritt, B. W. Kennedy, W. M. Sang, P. Jovanovic, Richard Nisius, D. Karlen, M. Hansroul, S. D. Talbot, Stan Bentvelsen, Christoph Schwick, T. Kress, M. J. Oreglia, J. E. Pilcher, Stephen Lloyd, Austin Ball, J. C. Hill, T. R. Junk, K. Graham, A. A. Carter, Ron Folman, P. S. Wells, B. List, Peter Krieger, Marco Cuffiani, Tara Shears, R. M. Brown, Ehud Duchovni, Lorne Levinson, Alessandro Montanari, W. J. McDonald, M. Jimack, B. C. Shen, A. M. Rossi, A. Biguzzi, J. G. Layter, F. Wäckerle, Terry Richard Wyatt, D. M. Gingrich, Randall Sobie, G. D. Lafferty, Giovanni Abbiendi, A. Michelini, J. R. Carter, C. R. Jones, Siegfried Bethke, D. Liu, A. K. Honma, W. G. Scott, T. Kobayashi, Juergen Thomas, J. Bechtluft, J. A. McKenna, Stefan Schmitt, G. N. Patrick, Daniele Bonacorsi, I. Nakamura, S. Rosati, R. J. Homer, C. Sbarra, F. R. Jacob, Sachio Komamiya, A. T. Watson, A. Harel, Ikuo Ueda, D. M. Strom, J. von Krogh, Guenter Duckeck, D. Glenzinski, J. Lu, Dezso Horvath, M. J. Losty, John Allison, T. P. Kokott, T. Saeki, Claudia Ciocca, K. Roscoe, Jean-Arcady Meyer, Klaus Kurt Desch, M. Gruwé, Shoji Asai, Alessandra Fanfani, R. Davis, E. Torrence, E. Clay, Achim Stahl, R. G. Kellogg, Daniel Lellouch, T. Behnke, Stefano Marcellini, A. W. Lloyd, Kiyotomo Kawagoe, G. W. Wilson, Takehiko Mori, D. E. Plane, P. Mättig, M. Hauschild, C. Markopoulos, G. M. Dallavalle, K. R. Hossain, James Pinfold, R. Perez-Ochoa, R. Seuster, J. Gascon, V. Zacek, M. A. Thomson, J. W. Gary, L. Brigliadori, Ekg Sarkisyan, E. K. U. Gross, Marcello Mannelli, M. Sproston, S. W. O'Neale, K. J. Anderson, Raimund Ströhmer, J. Letts, P. Poffenberger, German Martinez, Beatrix Dienes, J. M. Roney, C. Y. Chang, P. Taras, D. Lanske, Koichi Nagai, J. Schieck, W. Mohr, M. Fierro, S. R. Lautenschlager, K. Sachs, O. Runolfsson, Shlomo Dado, Claudio Grandi, J. S. White, Giora Mikenberg, S. F. Ashby, A. D. Schaile, Gabriella Pasztor, P. Vannerem, G. A. Snow, C. P. Ward, S. Söldner-Rembold, G. Gaycken, and P. G. Bright-Thomas

Subjects
Physics, Quantum chromodynamics, Particle physics, Annihilation, Physics and Astronomy (miscellaneous), Hadron, Monte Carlo method, Fizikai tudományok, Multiplicity (mathematics), Bose–Einstein correlations, law.invention, Nuclear physics, Természettudományok, law, Intermittency, High Energy Physics::Experiment, Engineering (miscellaneous), Cumulant, Particle Physics - Experiment
Abstract

A multidimensional study of local multiplicity fluctuations and multiparticle correlations of hadrons produced in Z decays is performed. The study is based on the data sample of more than 4 million events recorded with the OPAL detector at LEP. The fluctuations and correlations are analysed in terms of the normalized scaled factorial moments and cumulants up to the fifth order. The moments are observed to have intermittency-like behaviour, which is found to be more pronounced with increasing dimension. The large data sample allows for the first time a study of the factorial cumulants in e+e- annihilation. The analysis of the cumulants shows the existence of genuine multiparticle correlations with a strong intermittency rise up to higher orders. These correlations are found to be stronger in higher dimensions. The decomposition of the factorial moments into lower-order correlations that the dynamical fluctuations have important contributions from genuine many-particle correlations. The Monte Carlo models JETSET 7.4 and HERWIG 5.9 are found to reproduce the trend of the measured moments and cumulants but they underestimate the magnitudes. The results are found to be consistent with QCD jet formation dynamics, although additional contributions from other mechanisms in the hadronization process cannot be excluded. A multidimensional study of local multiplicity fluctuations and multiparticle correlations of hadrons produced in Z decays is performed. The study is based on the data sample of more than 4 million events recorded with the OPAL detector at LEP. The fluctuations and correlations are analysed in terms of the normalized scaled factorial moments and cumulants up to the fifth order. The moments are observed to have intermittency-like behaviour, which is found to be more pronounced with increasing dimension. The large data sample allows for the first time a study of the factorial cumulants in e+e- annihilation. The analysis of the cumulants shows the existence of genuine multiparticle correlations with a strong intermittency rise up to higher orders. These correlations are found to be stronger in higher dimensions. The decomposition of the factorial moments into lower-order correlations shows that the dynamical fluctuations have important contributions from genuine many-particle correlations. The Monte Carlo models JETSET 7.4 and HERWIG 5.9 are found to reproduce the trend of the measured moments and cumulants but they underestimate the magnitudes. The results are found to be consistent with QCD jet formation dynamics, although additional contributions from other mechanisms in the hadronization process cannot be excluded.

Published
1999

30. A measurement of the product branching ratio $f ({\rm b} \to \Lambda_{\rm b}) \cdot{\rm BR} (\Lambda_{\rm b} \to \Lambda {\rm X})$ in ${\rm Z}^0$ decays

Author

Raimund Ströhmer, A. Harel, Ikuo Ueda, D. M. Strom, P. G. Estabrooks, R. K. Keeler, P. Poffenberger, Dave Charlton, N. K. Watson, Michael Hildreth, Sachio Komamiya, Alain Bellerive, A. T. Watson, Claire Shepherd-Themistocleous, N. L. Rodning, P. Dervan, Otmar Biebel, F. Scharf, German Martinez, W. M. Sang, Beatrix Dienes, P. M. Watkins, S. Yamashita, A. Macpherson, R. D. Heuer, T. P. Kokott, S. M. Gascon-Shotkin, P. Igo-Kemenes, M. Hoch, K. Ishii, H. Jeremie, T. J. McMahon, C. Couyoumtzelis, T. Saeki, Gideon Bella, Achim Stahl, R. Howard, T. R. Junk, J. Dubbert, P. S. Wells, R. Davis, Terry Richard Wyatt, A. M. Rossi, R. K. Carnegie, H. J. Burckhart, Jacqueline Batley, P. I. Kayal, M. Herndon, A. A. Faust, O. Schaile, R. L. Coxe, D. R. Rust, J. A. Wilson, J. Böhme, J. Lauber, C. Sbarra, Norbert Wermes, F. R. Jacob, J. Grunhaus, Sherry Towers, T. Kawamoto, S. Robertson, L. Brigliadori, M. A. Thomson, M. Boutemeur, F. S. Merritt, H. Mes, A. Hocker, E. K. U. Gross, D. Lazic, I. P. Duerdoth, S. Braibant, C. R. Jones, S. Orito, Sven Menke, O. C. Cooke, A. M. Lee, John Allison, E. von Törne, M. Sproston, D. Chrisman, G. D. Long, Volker Blobel, P. Pfeifenschneider, Kiyotomo Kawagoe, Claudia Ciocca, A. W. Lloyd, Juergen Thomas, G. W. Wilson, S. R. Lautenschlager, G. Yekutieli, J. Patt, André Schöning, P. Hüntemeyer, M. Przybycień, Stephen Lloyd, T. Kress, R. G. Kellogg, O. Sahr, J. Bechtluft, M. Fanti, A. A. Carter, S. W. O'Neale, J. A. McKenna, Ron Folman, M. Hauschild, C. Markopoulos, K. J. Anderson, Stefano Marcellini, R. Mir, R. Hawkings, O. Runolfsson, J. M. Roney, S. D. Talbot, Ehud Duchovni, C. Y. Chang, Robert McPherson, G. Gaycken, P. G. Bright-Thomas, Paul Kyberd, Giovanni Abbiendi, F. K. Loebinger, Peter R Hobson, M. Jimack, H. Landsman, Koichi Nagai, Paolo Giacomelli, Claudio Grandi, D. Zer-Zion, R. Bartoldus, M. Hansroul, J. Schieck, H. O. Ogren, M. Schumacher, Fabrizio Fabbri, P. Taras, W. Mohr, J. Steuerer, Ivor Fleck, A. Michelini, A. Macchiolo, J. S. White, Ekg Sarkisyan, K. Stephens, Joleen Pater, J. Letts, A. Klier, Christoph Geich-Gimbel, F. Odorici, S. Baumann, Daniele Bonacorsi, R. Van Kooten, E. A. Mckigney, C. Hartmann, D. E. Plane, C. Littlewood, D. Eatough, Satoshi Tanaka, H. A. Neal, T. Kobayashi, R. J. Homer, T. Behnke, V. Gibson, K. R. Hossain, Vakhtang Kartvelishvili, F. G. Oakham, J. von Krogh, T. Kuhl, B. Schmitt, K. Hoffman, E. L. Barberio, G. M. Dallavalle, F. Wäckerle, D. M. Gingrich, J. E. Conboy, A. Fürtjes, Stefan Schmitt, M. Gruwé, I. Trigger, D. R. Ward, Richard Nisius, D. Lanske, B. List, D. C. Imrie, Gregor Herten, N. Altekamp, H. Voss, R. Kowalewski, Satoshi Mihara, S. Arcelli, R. J. Barlow, D. J. Miller, K. Roscoe, J. E. Pilcher, Marco Cuffiani, P. Gagnon, Gideon Alexander, S. Spagnolo, Klaus Kurt Desch, D. I. Futyan, Paolo Capiluppi, G. P. Siroli, M. Fierro, R. J. Hemingway, E. Torrence, E. Clay, K. Sachs, Christoph Schwick, Christopher Hawkes, B. W. Kennedy, P. Jovanovic, Austin Ball, Peter Krieger, Alessandro Montanari, C. Darling, W. R. Gibson, K. Harder, W. J. McDonald, B. C. Shen, A. Sittler, Zoltan Laszlo Trocsanyi, Shlomo Dado, Dong Hee Kim, R. M. Brown, Lorne Levinson, Siegfried Bethke, D. Liu, A. K. Honma, W. G. Scott, I. Nakamura, S. D. Bird, D. Axen, A. Jawahery, Peter Sherwood, Alexander Wagner, J. Ludwig, D. Glenzinski, Shoji Asai, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, Giora Mikenberg, S. F. Ashby, K. Runge, P. Bock, I. J. Bloodworth, A. D. Schaile, Gabriella Pasztor, P. Vannerem, Georges Azuelos, E. Tsur, S. A. Robins, G. A. Snow, C. P. Ward, S. Söldner-Rembold, M. Verzocchi, Yoram Rozen, K. W. Bell, R. Liebisch, K. Ackerstaff, J. Pálinkás, J. C. Hill, J. Polok, D. Karlen, Daniel Lellouch, Erez Etzion, Takehiko Mori, Stefan Kluth, P. Mättig, Shlomit Tarem, B. Surrow, J. Goldberg, B. Nellen, I. Cohen, Christoph Rembser, Matthias Schröder, M. Thiergen, K. Graham, Tara Shears, A. J. Martin, W. Mader, C. K. Hargrove, A. Biguzzi, J. G. Layter, S. Betts, M. Hapke, P. E.L. Clarke, J. P. Martin, M. J. Oreglia, S. De Jong, H. Rick, G. G. Hanson, J. R. Carter, G. Giacomelli, I. Lawson, James Pinfold, R. Perez-Ochoa, R. Seuster, J. Gascon, G. N. Patrick, A. De Roeck, M. Kobel, V. Zacek, J. W. Gary, M. S. Dixit, Frans Meijers, D. S. Koetke, Marcello Mannelli, K. Stoll, Andris Skuja, S. Petzold, Randall Sobie, G. D. Lafferty, Tetsuro Mashimo, M. F. Turner-Watson, Guenter Duckeck, Richard Teuscher, A. S. Turcot, F. Fiedler, W. Gorn, M. Kolrep, S. B. Anderson, P. Scharff-Hansen, Stan Bentvelsen, and A. M. Smith

Subjects
Physics, Physics and Astronomy (miscellaneous), Branching fraction, High Energy Physics::Phenomenology, High Energy Physics::Experiment, B meson, Atomic physics, Lambda, Engineering (miscellaneous)
Abstract

The product branching ratio, \(f ({\rm b} \to \Lambda_{\rm b}) \cdot{\rm BR} (\Lambda_{\rm b} \to \Lambda{\rm X})\), where \(\Lambda_{\rm b}\) denotes any weakly-decaying b–baryon, has been measured using the OPAL detector at LEP. \(\Lambda_{\rm b}\)'s are selected by the presence of energetic \(\Lambda\) particles in bottom events tagged by the presence of displaced secondary vertices. A fit to the momenta of the \(\Lambda\) particles separates signal from B meson and fragmentation backgrounds. The measured product branching ratio is \(\) Combined with a previous OPAL measurement, one obtains \(\)

Published
1999

31. Search for scalar top and scalar bottom quarks at = 189 GeV at LEP

Author

G Abbiendi, K Ackerstaff, G Alexander, J Allison, N Altekamp, K.J Anderson, S Anderson, S Arcelli, S Asai, S.F Ashby, D Axen, G Azuelos, A.H Ball, E Barberio, R.J Barlow, J.R Batley, S Baumann, J Bechtluft, T Behnke, K.W Bell, G Bella, A Bellerive, S Bentvelsen, S Bethke, S Betts, O Biebel, A Biguzzi, V Blobel, I.J Bloodworth, P Bock, J Böhme, D Bonacorsi, M Boutemeur, S Braibant, P Bright-Thomas, L Brigliadori, R.M Brown, H.J Burckhart, P Capiluppi, R.K Carnegie, A.A Carter, J.R Carter, C.Y Chang, D.G Charlton, D Chrisman, C Ciocca, P.E.L Clarke, E Clay, I Cohen, J.E Conboy, O.C Cooke, C Couyoumtzelis, R.L Coxe, M Cuffiani, S Dado, G.M Dallavalle, R Davis, S De Jong, A de Roeck, P Dervan, K Desch, B Dienes, M.S Dixit, J Dubbert, E Duchovni, G Duckeck, I.P Duerdoth, P.G Estabrooks, E Etzion, F Fabbri, A Fanfani, M Fanti, A.A Faust, F Fiedler, M Fierro, I Fleck, R Folman, A Frey, A Fürtjes, D.I Futyan, P Gagnon, J.W Gary, J Gascon, S.M Gascon-Shotkin, G Gaycken, C Geich-Gimbel, G Giacomelli, P Giacomelli, V Gibson, W.R Gibson, D.M Gingrich, D Glenzinski, J Goldberg, W Gorn, C Grandi, K Graham, E Gross, J Grunhaus, M Gruwé, G.G Hanson, M Hansroul, M Hapke, K Harder, A Harel, C.K Hargrove, M Hauschild, C.M Hawkes, R Hawkings, R.J Hemingway, M Herndon, G Herten, R.D Heuer, M.D Hildreth, J.C Hill, P.R Hobson, M Hoch, A Hocker, K Hoffman, R.J Homer, A.K Honma, D Horváth, K.R Hossain, R Howard, P Hüntemeyer, P Igo-Kemenes, D.C Imrie, K Ishii, F.R Jacob, A Jawahery, H Jeremie, M Jimack, C.R Jones, P Jovanovic, T.R Junk, J Kanzaki, D Karlen, V Kartvelishvili, K Kawagoe, T Kawamoto, P.I Kayal, R.K Keeler, R.G Kellogg, B.W Kennedy, D.H Kim, A Klier, T Kobayashi, M Kobel, T.P Kokott, M Kolrep, S Komamiya, R.V Kowalewski, T Kress, P Krieger, J von Krogh, T Kuhl, P Kyberd, G.D Lafferty, H Landsman, D Lanske, J Lauber, S.R Lautenschlager, I Lawson, J.G Layter, A.M Lee, D Lellouch, J Letts, L Levinson, R Liebisch, B List, C Littlewood, A.W Lloyd, S.L Lloyd, F.K Loebinger, G.D Long, M.J Losty, J Lu, J Ludwig, D Liu, A Macchiolo, A Macpherson, W Mader, M Mannelli, S Marcellini, C Markopoulos, A.J Martin, J.P Martin, G Martinez, T Mashimo, P Mättig, W.J McDonald, J McKenna, E.A Mckigney, T.J McMahon, R.A McPherson, F Meijers, S Menke, F.S Merritt, H Mes, J Meyer, A Michelini, S Mihara, G Mikenberg, D.J Miller, R Mir, W Mohr, A Montanari, T Mori, K Nagai, I Nakamura, H.A Neal, R Nisius, S.W O'Neale, F.G Oakham, F Odorici, H.O Ogren, M.J Oreglia, S Orito, J Pálinkás, G Pásztor, J.R Pater, G.N Patrick, J Patt, R Perez-Ochoa, S Petzold, P Pfeifenschneider, J.E Pilcher, J Pinfold, D.E Plane, P Poffenberger, B Poli, J Polok, M Przybycień, C Rembser, H Rick, S Robertson, S.A Robins, N Rodning, J.M Roney, S Rosati, K Roscoe, A.M Rossi, Y Rozen, K Runge, O Runolfsson, D.R Rust, K Sachs, T Saeki, O Sahr, W.M Sang, E.K.G Sarkisyan, C Sbarra, A.D Schaile, O Schaile, P Scharff-Hansen, J Schieck, S Schmitt, A Schöning, M Schröder, M Schumacher, C Schwick, W.G Scott, R Seuster, T.G Shears, B.C Shen, C.H Shepherd-Themistocleous, P Sherwood, G.P Siroli, A Sittler, A Skuja, A.M Smith, G.A Snow, R Sobie, S Söldner-Rembold, S Spagnolo, M Sproston, A Stahl, K Stephens, J Steuerer, K Stoll, D Strom, R Ströhmer, B Surrow, S.D Talbot, P Taras, S Tarem, R Teuscher, M Thiergen, J Thomas, M.A Thomson, E Torrence, S Towers, I Trigger, Z Trócsányi, E Tsur, A.S Turcot, M.F Turner-Watson, I Ueda, R Van Kooten, P Vannerem, M Verzocchi, H Voss, F Wäckerle, A Wagner, C.P Ward, D.R Ward, P.M Watkins, A.T Watson, N.K Watson, P.S Wells, N Wermes, J.S White, G.W Wilson, J.A Wilson, T.R Wyatt, S Yamashita, G Yekutieli, V Zacek, and D Zer-Zion

Subjects
Quark, Nuclear and High Energy Physics, Top quark, Particle physics, High Energy Physics::Lattice, Nuclear Theory, FOS: Physical sciences, Fizikai tudományok, 7. Clean energy, 01 natural sciences, Bottom quark, High Energy Physics - Experiment, Charm quark, High Energy Physics - Experiment (hep-ex), Természettudományok, 0103 physical sciences, 010306 general physics, Physics, 010308 nuclear & particles physics, High Energy Physics::Phenomenology, Scalar (physics), Neutralino, High Energy Physics::Experiment, Neutrino, Particle Physics - Experiment, Lepton
Abstract

Searches for a scalar top quark and a scalar bottom quark have been performed using a data sample of 182 pb-1 at a centre-of-mass energy of 189 GeV collected with the OPAL detector at LEP. No evidence for a signal was found. The 95% confidence level lower limit on the scalar top quark mass is 90.3 GeV if the mixing angle between the supersymmetric partners of the left- and right-handed states of the top quark is zero. In the worst case, when the scalar top quark decouples from the Z boson, the lower limit is 87.2 GeV. These limits were obtained assuming that the scalar top quark decays into a charm quark and the lightest neutralino, and that the mass difference between the scalar top quark and the lightest neutralino is larger than 10 GeV. The complementary decay mode of the scalar top quark decaying into a bottom quark, a charged lepton and a scalar neutrino has also been studied. From a search for the scalar bottom quark, a mass limit of 88.6 GeV was obtained if the mass difference between the scalar bottom quark and the lightest neutralino is larger than 7 GeV. These limits significantly improve the previous OPAL limits., 18 pages, LaTeX, including 4 eps figures, submitted to Physics Letters B

Published
1999

32. Colour reconnection studies in e+e−→W+W− at GeV

Author

G. Abbiendi, K. Ackerstaff, G. Alexander, J. Allison, N. Altekamp, K.J. Anderson, S. Anderson, S. Arcelli, S. Asai, S.F. Ashby, D. Axen, G. Azuelos, A.H. Ball, E. Barberio, R.J. Barlow, R. Bartoldus, J.R. Batley, S. Baumann, J. Bechtluft, T. Behnke, K.W. Bell, G. Bella, A. Bellerive, S. Bentvelsen, S. Bethke, S. Betts, O. Biebel, A. Biguzzi, S.D. Bird, V. Blobel, I.J. Bloodworth, P. Bock, J. Böhme, D. Bonacorsi, M. Boutemeur, S. Braibant, P. Bright-Thomas, L. Brigliadori, R.M. Brown, H.J. Burckhart, P. Capiluppi, R.K. Carnegie, A.A. Carter, J.R. Carter, C.Y. Chang, D.G. Charlton, D. Chrisman, C. Ciocca, P.E.L. Clarke, E. Clay, I. Cohen, J.E. Conboy, O.C. Cooke, C. Couyoumtzelis, R.L. Coxe, M. Cuffiani, S. Dado, G.M. Dallavalle, R. Davis, S. De Jong, A. de Roeck, P. Dervan, K. Desch, B. Dienes, M.S. Dixit, J. Dubbert, E. Duchovni, G. Duckeck, I.P. Duerdoth, D. Eatough, P.G. Estabrooks, E. Etzion, F. Fabbri, M. Fanti, A.A. Faust, F. Fiedler, M. Fierro, I. Fleck, R. Folman, A. Fürtjes, D.I. Futyan, P. Gagnon, J.W. Gary, J. Gascon, S.M. Gascon-Shotkin, G. Gaycken, C. Geich-Gimbel, G. Giacomelli, P. Giacomelli, V. Gibson, W.R. Gibson, D.M. Gingrich, D. Glenzinski, J. Goldberg, W. Gorn, C. Grandi, K. Graham, E. Gross, J. Grunhaus, M. Gruwé, G.G. Hanson, M. Hansroul, M. Hapke, K. Harder, A. Harel, C.K. Hargrove, C. Hartmann, M. Hauschild, C.M. Hawkes, R. Hawkings, R.J. Hemingway, M. Herndon, G. Herten, R.D. Heuer, M.D. Hildreth, J.C. Hill, P.R. Hobson, M. Hoch, A. Hocker, K. Hoffman, R.J. Homer, A.K. Honma, D. Horváth, K.R. Hossain, R. Howard, P. Hüntemeyer, P. Igo-Kemenes, D.C. Imrie, K. Ishii, F.R. Jacob, A. Jawahery, H. Jeremie, M. Jimack, C.R. Jones, P. Jovanovic, T.R. Junk, D. Karlen, V. Kartvelishvili, K. Kawagoe, T. Kawamoto, P.I. Kayal, R.K. Keeler, R.G. Kellogg, B.W. Kennedy, D.H. Kim, A. Klier, S. Kluth, T. Kobayashi, M. Kobel, D.S. Koetke, T.P. Kokott, M. Kolrep, S. Komamiya, R.V. Kowalewski, T. Kress, P. Krieger, J. von Krogh, T. Kuhl, P. Kyberd, G.D. Lafferty, H. Landsman, D. Lanske, J. Lauber, S.R. Lautenschlager, I. Lawson, J.G. Layter, D. Lazic, A.M. Lee, D. Lellouch, J. Letts, L. Levinson, R. Liebisch, B. List, C. Littlewood, A.W. Lloyd, S.L. Lloyd, F.K. Loebinger, G.D. Long, M.J. Losty, J. Ludwig, D. Liu, A. Macchiolo, A. Macpherson, W. Mader, M. Mannelli, S. Marcellini, C. Markopoulos, A.J. Martin, J.P. Martin, G. Martinez, T. Mashimo, P. Mättig, W.J. McDonald, J. McKenna, E.A. Mckigney, T.J. McMahon, R.A. McPherson, F. Meijers, S. Menke, F.S. Merritt, H. Mes, J. Meyer, A. Michelini, S. Mihara, G. Mikenberg, D.J. Miller, R. Mir, W. Mohr, A. Montanari, T. Mori, K. Nagai, I. Nakamura, H.A. Neal, B. Nellen, R. Nisius, S.W. O'Neale, F.G. Oakham, F. Odorici, H.O. Ogren, M.J. Oreglia, S. Orito, J. Pálinkás, G. Pásztor, J.R. Pater, G.N. Patrick, J. Patt, R. Perez-Ochoa, S. Petzold, P. Pfeifenschneider, J.E. Pilcher, J. Pinfold, D.E. Plane, P. Poffenberger, J. Polok, M. Przybycień, C. Rembser, H. Rick, S. Robertson, S.A. Robins, N. Rodning, J.M. Roney, K. Roscoe, A.M. Rossi, Y. Rozen, K. Runge, O. Runolfsson, D.R. Rust, K. Sachs, T. Saeki, O. Sahr, W.M. Sang, E.K.G. Sarkisyan, C. Sbarra, A.D. Schaile, O. Schaile, F. Scharf, P. Scharff-Hansen, J. Schieck, B. Schmitt, S. Schmitt, A. Schöning, M. Schröder, M. Schumacher, C. Schwick, W.G. Scott, R. Seuster, T.G. Shears, B.C. Shen, C.H. Shepherd-Themistocleous, P. Sherwood, G.P. Siroli, A. Sittler, A. Skuja, A.M. Smith, G.A. Snow, R. Sobie, S. Söldner-Rembold, S. Spagnolo, M. Sproston, A. Stahl, K. Stephens, J. Steuerer, K. Stoll, D. Strom, R. Ströhmer, B. Surrow, S.D. Talbot, P. Taras, S. Tarem, R. Teuscher, M. Thiergen, J. Thomas, M.A. Thomson, E. von Törne, E. Torrence, S. Towers, I. Trigger, Z. Trócsányi, E. Tsur, A.S. Turcot, M.F. Turner-Watson, I. Ueda, R. Van Kooten, P. Vannerem, M. Verzocchi, H. Voss, F. Wäckerle, A. Wagner, C.P. Ward, D.R. Ward, P.M. Watkins, A.T. Watson, N.K. Watson, P.S. Wells, N. Wermes, J.S. White, G.W. Wilson, J.A. Wilson, T.R. Wyatt, S. Yamashita, G. Yekutieli, V. Zacek, and D. Zer-Zion

Subjects
Quantum chromodynamics, Physics, Nuclear and High Energy Physics, Particle physics, 010308 nuclear & particles physics, Hadron, Observable, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Charged particle, 0103 physical sciences, Statistical precision, High Energy Physics::Experiment, Rapidity, Multiplicity (chemistry), 010306 general physics, Boson
Abstract

The predicted effects of final state interactions such as colour reconnection are investigated by measuring properties of hadronic decays of W bosons, recorded at a centre-of-mass energy of sqrt(s)=182.7 GeV in the OPAL detector at LEP. Dependence on the modelling of hadronic W decays is avoided by comparing W+W- -> qqqq events with the non-leptonic component of W+W- -> qqlnu events. The scaled momentum distribution, its mean value, x_p, and that of the charged particle multiplicity, n_ch, are measured and found to be consistent in the two channels. The measured differences are: Diff(x_p) = +0.7 +- 0.8 +- 0.6 and Diff(n_ch) = (-0.09 +- 0.09 +-0.05)*10**-2. In addition, measurements of rapidity and thrust are performed for W+W- -> qqqq events. The data are described well by standard QCD models and disfavour one model of colour reconnection within the ARIADNE program. The current implementation of the ELLIS-GEIGER model of colour reconnection is excluded. At the current level of statistical precision no evidence for colour reconnection effects was found in the observables studied. The predicted effect of colour reconnection on OPAL measurements of M_W is also quantified in the context of models studied.

Published
1999

33. Search for anomalous photonic events with missing energy in ${\rm e}^+{\rm e}^-$ collisions at $\sqrt{s}$ = 130, 136 and 183 GeV

Author

Sachio Komamiya, A. T. Watson, M. Boutemeur, F. S. Merritt, F. Scharf, T. P. Kokott, J. Letts, T. Saeki, Satoshi Mihara, German Martinez, J. Bechtluft, J. A. McKenna, G. G. Hanson, P. Scharff-Hansen, R. Davis, Randall Sobie, G. D. Lafferty, K. Sachs, S. Betts, M. Hapke, M. Fanti, G. Giacomelli, M. J. Oreglia, I. Lawson, Shlomo Dado, J. R. Carter, G. N. Patrick, A. M. Smith, Dave Charlton, R. Bartoldus, A. De Roeck, W. R. Gibson, H. O. Ogren, Christoph Geich-Gimbel, N. Altekamp, H. Voss, Guenter Duckeck, J. M. Roney, Robert McPherson, J. Grunhaus, S. R. Lautenschlager, K. Stoll, Andris Skuja, D. M. Strom, Gregor Herten, K. Harder, R. J. Barlow, G. Gaycken, P. G. Bright-Thomas, R. D. Heuer, D. J. Miller, Fabrizio Fabbri, D. C. Imrie, Claire Shepherd-Themistocleous, M. Schumacher, S. Petzold, R. Bürgin, O. Runolfsson, R. M. Brown, Lorne Levinson, M. S. Dixit, Frans Meijers, Giora Mikenberg, S. F. Ashby, Koichi Nagai, J. Schieck, Tetsuro Mashimo, Achim Stahl, Vakhtang Kartvelishvili, Paul Kyberd, J. E. Conboy, A. Fürtjes, C. Y. Chang, Ehud Duchovni, W. Mohr, M. Jimack, G. P. Siroli, J. E. Pilcher, F. Odorici, R. Van Kooten, T. R. Junk, A. Biguzzi, A. A. Faust, W. Gorn, P. Taras, F. K. Loebinger, P. S. Wells, Claudio Grandi, J. S. White, Christoph Schwick, A. Michelini, J. Steuerer, J. G. Layter, A. W. Lloyd, Ekg Sarkisyan, R. J. Hemingway, C. Hartmann, S. B. Anderson, D. E. Plane, Terry Richard Wyatt, Gideon Bella, K. Stephens, Stephen Hillier, H. A. Neal, G. M. Dallavalle, Ivor Fleck, G. W. Wilson, Satoshi Tanaka, Joleen Pater, A. D. Schaile, Gabriella Pasztor, M. Hauschild, C. Markopoulos, P. Vannerem, M. A. Thomson, A. Macpherson, H. J. Burckhart, Jacqueline Batley, F. Wäckerle, C. Littlewood, B. W. Kennedy, James Pinfold, R. Perez-Ochoa, R. Seuster, P. Jovanovic, A. Klier, Austin Ball, D. M. Gingrich, T. Kobayashi, E. K. U. Gross, L. Brigliadori, V. Gibson, H. Mes, S. M. Gascon-Shotkin, Peter Krieger, J. Gascon, R. Howard, Stan Bentvelsen, M. Sproston, K. Roscoe, G. A. Snow, C. P. Ward, Alessandro Montanari, D. Lanske, M. F. Turner-Watson, I. Trigger, I. P. Duerdoth, S. Braibant, A. Macchiolo, Peter R Hobson, D. R. Rust, P. E.L. Clarke, Klaus Kurt Desch, E. Torrence, M. Kobel, S. Söldner-Rembold, D. R. Ward, T. Kress, C. M. Hawkes, R. Mir, J. P. Martin, E. Clay, Otmar Biebel, R. Kowalewski, V. Zacek, R. Hawkings, S. W. O'Neale, K. J. Anderson, D. Zer-Zion, O. C. Cooke, P. Hüntemeyer, S. Arcelli, A. M. Lee, P. I. Kayal, Georges Azuelos, P. Pfeifenschneider, T. Kuhl, John Allison, J. W. Gary, Raimund Ströhmer, Norbert Wermes, E. von Törne, Sherry Towers, T. Kawamoto, S. De Jong, E. Tsur, D. S. Koetke, Marcello Mannelli, Richard Teuscher, A. S. Turcot, C. R. Jones, S. Orito, J. Patt, Richard Nisius, A. M. Rossi, André Schöning, P. Poffenberger, M. Fierro, M. Verzocchi, K. W. Bell, H. Rick, O. Sahr, F. G. Oakham, B. List, Marco Cuffiani, F. Fiedler, J. Pálinkás, Kiyotomo Kawagoe, B. Schmitt, E. L. Barberio, Gideon Alexander, Paolo Giacomelli, M. Hansroul, Paolo Capiluppi, J. C. Hill, Beatrix Dienes, C. Burgard, R. J. Homer, R. G. Kellogg, R. L. Coxe, W. J. McDonald, B. C. Shen, A. Hocker, M. Kolrep, Siegfried Bethke, D. Liu, A. K. Honma, D. Chrisman, G. D. Long, K. R. Hossain, Stefano Marcellini, Volker Blobel, W. G. Scott, I. Nakamura, Stephen Lloyd, W. M. Sang, Claudia Ciocca, D. Glenzinski, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, Michael Hildreth, Alain Bellerive, N. L. Rodning, C. Sbarra, F. R. Jacob, Daniele Bonacorsi, J. Lauber, J. von Krogh, S. D. Talbot, M. Gruwé, L. A. del Pozo, T. J. McMahon, C. Couyoumtzelis, J. Dubbert, R. K. Carnegie, M. Herndon, D. Eatough, T. Behnke, M. Bobinski, J. A. Wilson, J. Böhme, D. Lazic, P. Gagnon, G. Yekutieli, M. Przybycień, A. A. Carter, Ron Folman, A. Sittler, Zoltan Laszlo Trocsanyi, Giovanni Abbiendi, S. D. Bird, D. Axen, A. Jawahery, Peter Sherwood, Stefan Schmitt, Alexander Wagner, J. Ludwig, K. Runge, P. Bock, Shoji Asai, P. G. Estabrooks, R. K. Keeler, Daniel Lellouch, N. K. Watson, Takehiko Mori, P. Mättig, P. M. Watkins, I. J. Bloodworth, S. Baumann, Yoram Rozen, E. A. Mckigney, J. Polok, D. Karlen, D. I. Futyan, J. Goldberg, B. Nellen, H. G. Evans, I. Cohen, Christoph Rembser, Erez Etzion, Stefan Kluth, Shlomit Tarem, B. Surrow, S. A. Robins, R. Liebisch, K. Ackerstaff, A. J. Martin, S. Yamashita, P. Igo-Kemenes, K. Ishii, H. Jeremie, W. Mader, O. Schaile, C. K. Hargrove, S. Robertson, Matthias Schröder, Sven Menke, M. Thiergen, and Tara Shears

Subjects
Physics, Particle physics, Missing energy, Physics and Astronomy (miscellaneous), Physics beyond the Standard Model, Standard Model, Nuclear physics, Pair production, Neutralino, High Energy Physics::Experiment, Gravitino, Production (computer science), Engineering (miscellaneous), Energy (signal processing)
Abstract

Photonic events with large missing energy have been observed in $\mathrm e^+e^-$ collisions at centre-of-mass energies of 130, 136 and 183 GeV collected in 1997 using the OPAL detector at LEP. Results are presented for event topologies with a single photon and missing transverse energy or with an acoplanar photon pair. Cross-section measurements are performed within the kinematic acceptance of each selection. These results are compared with the expectations from the Standard Model process ${\rm e}^+{\rm e}^-\to\nu\overline{\nu}$ + photon(s). No evidence is observed for new physics contributions to these final states. Using the data at $\sqrt{s}$ = 183 GeV, upper limits on ${\sigma({\rm e^+e^-}\to{\rm XY})\cdot{\rm BR}(\rm X \to Y \gamma)}$ and ${\sigma({\rm e^+e^-}\to{\rm XX})\cdot{\rm BR}^2(\rm X \to Y \gamma)}$ are derived for the case of stable and invisible Y. These limits apply to single and pair production of excited neutrinos ( $\rm X = \nu^*, Y = \nu$ ), to neutralino production ( $\rm X={{\tilde{\chi}}^{0}}_{2}, Y={{\tilde{\chi}}^{0}}_{1}$ ) and to supersymmetric models in which $\rm X = {{\tilde{\chi}}^{0}}_{1}$ and $\rm Y=\tilde{\mathrm{G}}$ is a light gravitino.

Published
1999

34. Measurements of flavour-dependent fragmentation functions in ${\bf Z^{0} \rightarrow{\rm q}\bar{\rm q}}$ events

Author

J. von Krogh, R. Bartoldus, G. Yekutieli, M. Przybycień, A. A. Carter, Ron Folman, J. Letts, M. Gruwé, L. A. del Pozo, P. G. Bright-Thomas, K. Stephens, M. Fanti, T. J. McMahon, C. Couyoumtzelis, J. Dubbert, R. K. Carnegie, M. Herndon, Daniel Lellouch, M. Bobinski, C. Y. Chang, J. A. Wilson, J. Böhme, H. O. Ogren, K. Roscoe, M. Schumacher, E. Lefebvre, D. Lazic, Takehiko Mori, P. Mättig, F. Odorici, Randall Sobie, T. Schorner, S. D. Bird, John Allison, Reda Tafirout, Klaus Kurt Desch, G. D. Lafferty, Christoph Geich-Gimbel, S. M. Gascon-Shotkin, Achim Stahl, James Pinfold, R. Perez-Ochoa, R. Seuster, C. Littlewood, V. Gibson, E. Torrence, F. Scharf, K. Sachs, Shlomo Dado, Georges Azuelos, E. Tsur, German Martinez, J. Gascon, T. R. Junk, D. Axen, P. E.L. Clarke, A. Jawahery, Robert McPherson, M. Verzocchi, H. A. Neal, I. Trigger, E. Clay, K. W. Bell, R. G. Kellogg, J. Pálinkás, D. R. Ward, T. Kress, J. C. Hill, J. P. Martin, Dave Charlton, P. G. Estabrooks, Vakhtang Kartvelishvili, Mathieu Doucet, V. Zacek, T. Behnke, W. J. McDonald, Peter Sherwood, R. K. Keeler, B. C. Shen, Stefano Marcellini, M. F. Turner-Watson, J. W. Gary, R. D. Heuer, D. S. Koetke, W. R. Gibson, Stefan Schmitt, Siegfried Bethke, J. E. Conboy, R. Kowalewski, S. De Jong, Marcello Mannelli, Fabrizio Fabbri, M. A. Thomson, A. K. Honma, W. G. Scott, Guenter Duckeck, A. Fürtjes, N. K. Watson, W. M. Sang, Kiyotomo Kawagoe, Peter R Hobson, R. Bürgin, Alexander Wagner, I. Nakamura, E. K. U. Gross, H. Mes, P. Scharff-Hansen, A. M. Rossi, K. Nagai, I. P. Duerdoth, S. Braibant, J. Ludwig, D. Zer-Zion, K. Runge, P. Bock, P. M. Watkins, M. Sproston, A. Macchiolo, O. C. Cooke, Gregor Herten, P. Pfeifenschneider, H. Rick, Shoji Asai, Giora Mikenberg, A. Joly, R. M. Brown, Lorne Levinson, A. M. Smith, S. F. Ashby, K. R. Hossain, D. R. Rust, C. M. Hawkes, D. Glenzinski, J. Patt, André Schöning, K. Stoll, Andris Skuja, M. Boutemeur, F. S. Merritt, I. J. Bloodworth, P. Hüntemeyer, S. B. Anderson, P. Gagnon, S. Petzold, C. Sbarra, Satoshi Mihara, Gideon Alexander, Dezso Horvath, M. J. Losty, F. R. Jacob, Jean-Arcady Meyer, Tetsuro Mashimo, O. Sahr, Paolo Capiluppi, J. Grunhaus, C. Hartmann, D. E. Plane, A. M. Lee, Gideon Bella, A. D. Schaile, W. Gorn, Paul Kyberd, F. K. Loebinger, A. Sittler, Stephen Hillier, E. von Törne, Gabriella Pasztor, J. M. Roney, R. L. Coxe, Zoltan Laszlo Trocsanyi, Richard Nisius, Stan Bentvelsen, M. Fierro, G. M. Dallavalle, Yoram Rozen, H. J. Burckhart, Jacqueline Batley, P. Vannerem, Michael Hildreth, J. Steuerer, Ivor Fleck, Silvia Arcelli, J. Bechtluft, B. List, J. A. McKenna, D. Lui, A. Hocker, Paolo Giacomelli, Joleen Pater, Marco Cuffiani, Richard Teuscher, G. A. Snow, A. Klier, A. S. Turcot, F. Fiedler, D. Chrisman, G. D. Long, M. Hansroul, Ekg Sarkisyan, C. P. Ward, Sachio Komamiya, N. L. Rodning, R. Van Kooten, Theodoros Geralis, J. Lauber, J. Schieck, Volker Blobel, A. T. Watson, W. Mohr, G. G. Hanson, C. Burgard, S. Söldner-Rembold, B. Poli, R. J. Homer, T. P. Kokott, Stephen Lloyd, T. Saeki, G. Giacomelli, I. Lawson, F. Wäckerle, S. D. Talbot, J. E. Pilcher, D. M. Gingrich, Alessandra Fanfani, R. Davis, Claire Shepherd-Themistocleous, Ehud Duchovni, S. Baumann, J. Polok, A. De Roeck, M. Kobel, D. Karlen, M. Kolrep, D. Eatough, M. Jimack, C. R. Jones, G. W. Wilson, A. Michelini, H. M. Fischer, E. A. Mckigney, M. S. Dixit, D. C. Imrie, P. Vikas, A. A. Faust, Frans Meijers, Satoshi Tanaka, T. Kobayashi, D. Lanske, S. Betts, M. Hapke, G. P. Siroli, S. R. Lautenschlager, A. Biguzzi, J. G. Layter, Christoph Schwick, Claudia Ciocca, O. Runolfsson, D. I. Futyan, Claudio Grandi, M. J. Oreglia, A. W. Lloyd, S. Yamashita, P. Igo-Kemenes, S. A. Robins, K. Ishii, H. Jeremie, M. Hauschild, C. Markopoulos, R. Liebisch, K. Ackerstaff, J. R. Carter, G. N. Patrick, O. Schaile, Otmar Biebel, S. Robertson, P. Taras, Raimund Ströhmer, P. Poffenberger, Beatrix Dienes, Sven Menke, S. W. O'Neale, K. J. Anderson, P. I. Kayal, Erez Etzion, Stefan Kluth, Shlomit Tarem, Norbert Wermes, Sherry Towers, T. Kawamoto, S. Orito, J. Goldberg, B. Nellen, H. G. Evans, I. Cohen, Christoph Rembser, P. S. Wells, Terry Richard Wyatt, A. Macpherson, A. J. Martin, C. K. Hargrove, Tara Shears, R. Howard, R. Mir, R. Hawkings, J. S. White, Matthias Schröder, M. Thiergen, D. M. Strom, F. G. Oakham, B. Schmitt, E. L. Barberio, N. Altekamp, H. Voss, R. J. Barlow, D. J. Miller, R. J. Hemingway, B. W. Kennedy, P. Jovanovic, Austin Ball, Peter Krieger, and Alessandro Montanari

Subjects
Quark, Physics, Particle physics, Physics and Astronomy (miscellaneous), Meson, 010308 nuclear & particles physics, High Energy Physics::Lattice, Electron–positron annihilation, High Energy Physics::Phenomenology, Flavour, 01 natural sciences, Bottom quark, Charged particle, Nuclear physics, 0103 physical sciences, High Energy Physics::Experiment, Charm (quantum number), 010306 general physics, Maxima, Engineering (miscellaneous)
Abstract

Fragmentation functions for charged particles in \({\rm Z}^0 \rightarrow {\rm q}\bar{\rm q}\) events have been measured for bottom (b), charm (c) and light (uds) quarks as well as for all flavours together. The results are based on data recorded between 1990 and 1995 using the OPAL detector at LEP. Event samples with different flavour compositions were formed using reconstructed \({\rm D}^{*\pm}\) mesons and secondary vertices. The \(\xi_{\rm p} =\ln(1/x_{\rm p})\) distributions and the position of their maxima \(\xi_0\) are also presented separately for uds, c and b quark events. The fragmentation function for b quarks is significantly softer than for uds quarks.

Published
1999

35. Search for baryon and lepton number violating Z0 decays

Author

G. Abbiendi, K. Ackerstaff, G. Alexander, J. Allison, N. Altekamp, K.J. Anderson, S. Anderson, S. Arcelli, S. Asai, S.F. Ashby, D. Axen, G. Azuelos, A.H. Ball, E. Barberio, R.J. Barlow, R. Bartoldus, J.R. Batley, S. Baumann, J. Bechtluft, T. Behnke, K.W. Bell, G. Bella, A. Bellerive, S. Bentvelsen, S. Bethke, S. Betts, O. Biebel, A. Biguzzi, S.D. Bird, V. Blobel, I.J. Bloodworth, P. Bock, J. Böhme, D. Bonacorsi, M. Boutemeur, S. Braibant, P. Bright-Thomas, L. Brigliadori, R.M. Brown, H.J. Burckhart, P. Capiluppi, R.K. Carnegie, A.A. Carter, J.R. Carter, C.Y. Chang, D.G. Charlton, D. Chrisman, C. Ciocca, P.E.L. Clarke, E. Clay, I. Cohen, J.E. Conboy, O.C. Cooke, C. Couyoumtzelis, R.L. Coxe, M. Cuffiani, S. Dado, G.M. Dallavalle, R. Davis, S. De Jong, A. de Roeck, P. Dervan, K. Desch, B. Dienes, M.S. Dixit, J. Dubbert, E. Duchovni, G. Duckeck, I.P. Duerdoth, D. Eatough, P.G. Estabrooks, E. Etzion, F. Fabbri, M. Fanti, A.A. Faust, F. Fiedler, M. Fierro, I. Fleck, R. Folman, A. Fürtjes, D.I. Futyan, P. Gagnon, J.W. Gary, J. Gascon, S.M. Gascon-Shotkin, G. Gaycken, C. Geich-Gimbel, G. Giacomelli, P. Giacomelli, V. Gibson, W.R. Gibson, D.M. Gingrich, D. Glenzinski, J. Goldberg, W. Gorn, C. Grandi, K. Graham, E. Gross, J. Grunhaus, M. Gruwé, G.G. Hanson, M. Hansroul, M. Hapke, K. Harder, A. Harel, C.K. Hargrove, C. Hartmann, M. Hauschild, C.M. Hawkes, R. Hawkings, R.J. Hemingway, M. Herndon, G. Herten, R.D. Heuer, M.D. Hildreth, J.C. Hill, P.R. Hobson, M. Hoch, A. Hocker, K. Hoffman, R.J. Homer, A.K. Honma, D. Horváth, K.R. Hossain, R. Howard, P. Hüntemeyer, P. Igo-Kemenes, D.C. Imrie, K. Ishii, F.R. Jacob, A. Jawahery, H. Jeremie, M. Jimack, C.R. Jones, P. Jovanovic, T.R. Junk, D. Karlen, V. Kartvelishvili, K. Kawagoe, T. Kawamoto, P.I. Kayal, R.K. Keeler, R.G. Kellogg, B.W. Kennedy, D.H. Kim, A. Klier, S. Kluth, T. Kobayashi, M. Kobel, D.S. Koetke, T.P. Kokott, M. Kolrep, S. Komamiya, R.V. Kowalewski, T. Kress, P. Krieger, J. von Krogh, T. Kuhl, P. Kyberd, G.D. Lafferty, H. Landsman, D. Lanske, J. Lauber, S.R. Lautenschlager, I. Lawson, J.G. Layter, D. Lazic, A.M. Lee, D. Lellouch, J. Letts, L. Levinson, R. Liebisch, B. List, C. Littlewood, A.W. Lloyd, S.L. Lloyd, F.K. Loebinger, G.D. Long, M.J. Losty, J. Ludwig, D. Liu, A. Macchiolo, A. Macpherson, W. Mader, M. Mannelli, S. Marcellini, C. Markopoulos, A.J. Martin, J.P. Martin, G. Martinez, T. Mashimo, P. Mättig, W.J. McDonald, J. McKenna, E.A. Mckigney, T.J. McMahon, R.A. McPherson, F. Meijers, S. Menke, F.S. Merritt, H. Mes, J. Meyer, A. Michelini, S. Mihara, G. Mikenberg, D.J. Miller, R. Mir, W. Mohr, A. Montanari, T. Mori, K. Nagai, I. Nakamura, H.A. Neal, B. Nellen, R. Nisius, S.W. O'Neale, F.G. Oakham, F. Odorici, H.O. Ogren, M.J. Oreglia, S. Orito, J. Pálinkás, G. Pásztor, J.R. Pater, G.N. Patrick, J. Patt, R. Perez-Ochoa, S. Petzold, P. Pfeifenschneider, J.E. Pilcher, J. Pinfold, D.E. Plane, P. Poffenberger, J. Polok, M. Przybycień, C. Rembser, H. Rick, S. Robertson, S.A. Robins, N. Rodning, J.M. Roney, K. Roscoe, A.M. Rossi, Y. Rozen, K. Runge, O. Runolfsson, D.R. Rust, K. Sachs, T. Saeki, O. Sahr, W.M. Sang, E.K.G. Sarkisyan, C. Sbarra, A.D. Schaile, O. Schaile, F. Scharf, P. Scharff-Hansen, J. Schieck, B. Schmitt, S. Schmitt, A. Schöning, M. Schröder, M. Schumacher, C. Schwick, W.G. Scott, R. Seuster, T.G. Shears, B.C. Shen, C.H. Shepherd-Themistocleous, P. Sherwood, G.P. Siroli, A. Sittler, A. Skuja, A.M. Smith, G.A. Snow, R. Sobie, S. Söldner-Rembold, S. Spagnolo, M. Sproston, A. Stahl, K. Stephens, J. Steuerer, K. Stoll, D. Strom, R. Ströhmer, B. Surrow, S.D. Talbot, S. Tanaka, P. Taras, S. Tarem, R. Teuscher, M. Thiergen, J. Thomas, M.A. Thomson, E. von Törne, E. Torrence, S. Towers, I. Trigger, Z. Trócsányi, E. Tsur, A.S. Turcot, M.F. Turner-Watson, I. Ueda, R. Van Kooten, P. Vannerem, M. Verzocchi, H. Voss, F. Wäckerle, A. Wagner, C.P. Ward, D.R. Ward, P.M. Watkins, A.T. Watson, N.K. Watson, P.S. Wells, N. Wermes, J.S. White, G.W. Wilson, J.A. Wilson, T.R. Wyatt, S. Yamashita, G. Yekutieli, V. Zacek, and D. Zer-Zion

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, 010308 nuclear & particles physics, High Energy Physics::Phenomenology, Detector, FOS: Physical sciences, Fizikai tudományok, Charge (physics), 01 natural sciences, Lepton number, High Energy Physics - Experiment, Baryon, High Energy Physics - Experiment (hep-ex), Természettudományok, 0103 physical sciences, High Energy Physics::Experiment, 010306 general physics, Particle Physics - Experiment, Conjugate
Abstract

Using data collected with the OPAL detector at LEP, we have searched for the processes e+e- -> Z0 -> p e-, p mu- and the charge conjugate final-states. These would violate the conservation of the baryon-number B, lepton-number L and the fermion-number n = (B+L). No evidence for such decays has been found, and the 95% confidence level upper limits on the partial widths Z0 -> p e and Z0 -> p mu are found to be 4.6 and 4.4 keV respectively., 16 pages, LaTeX, 2 ps figs included, submitted to Physics Letters B

Published
1999

36. A measurement of the τ→ν branching ratio

Author

S. M. Gascon-Shotkin, P. Poffenberger, A. D. Schaile, Gabriella Pasztor, John Allison, G. Gaycken, P. G. Bright-Thomas, J. Lauber, Erez Etzion, G. Yekutieli, A. J. Martin, M. Przybycień, Stefan Kluth, Shlomit Tarem, Beatrix Dienes, M. Schumacher, P. Gagnon, P. Vannerem, S. D. Talbot, A. Sittler, Zoltan Laszlo Trocsanyi, Dong Hee Kim, T. Kress, Daniel Lellouch, R. G. Kellogg, A. M. Rossi, A. A. Carter, Ron Folman, D. Eatough, Takehiko Mori, F. Odorici, B. Surrow, G. A. Snow, C. P. Ward, T. Behnke, W. Mader, Stefano Marcellini, S. D. Bird, P. Mättig, C. K. Hargrove, S. Söldner-Rembold, H. A. Neal, D. Axen, A. Jawahery, M. Fanti, C. Y. Chang, S. A. Robins, P. G. Estabrooks, R. K. Keeler, D. C. Imrie, Dave Charlton, Claire Shepherd-Themistocleous, Peter Sherwood, Alexander Wagner, Giovanni Abbiendi, J. Ludwig, K. Runge, P. Bock, N. K. Watson, Matthias Schröder, P. Taras, Paul Kyberd, F. K. Loebinger, K. Hoffman, R. Liebisch, K. Ackerstaff, J. Steuerer, T. R. Junk, G. P. Siroli, E. Tsur, Ivor Fleck, M. Thiergen, S. R. Lautenschlager, Stefan Schmitt, P. S. Wells, P. M. Watkins, T. J. McMahon, M. Verzocchi, K. W. Bell, Joleen Pater, C. Couyoumtzelis, A. Klier, Christoph Schwick, R. J. Hemingway, J. Pálinkás, S. B. Anderson, M. Boutemeur, F. S. Merritt, A. A. Faust, R. D. Heuer, J. Dubbert, R. K. Carnegie, K. Sachs, M. Herndon, James Pinfold, R. Perez-Ochoa, R. Seuster, Terry Richard Wyatt, J. C. Hill, Robert McPherson, Christopher Hawkes, J. A. Wilson, J. Böhme, Shoji Asai, W. M. Sang, Shlomo Dado, L. Brigliadori, O. Runolfsson, Claudia Ciocca, B. W. Kennedy, P. Jovanovic, Gideon Bella, I. J. Bloodworth, Gregor Herten, W. J. McDonald, B. C. Shen, J. Gascon, S. Baumann, D. Lazic, K. Graham, H. J. Burckhart, Jacqueline Batley, A. Macpherson, Tara Shears, Daniele Bonacorsi, Fabrizio Fabbri, Giora Mikenberg, J. Goldberg, Siegfried Bethke, D. Liu, A. K. Honma, E. A. Mckigney, Austin Ball, Yoram Rozen, J. Bechtluft, J. A. McKenna, Peter Krieger, V. Zacek, Claudio Grandi, W. G. Scott, Michael Hildreth, B. Nellen, Stan Bentvelsen, C. Sbarra, G. Azuelos, F. R. Jacob, S. F. Ashby, I. Nakamura, J. S. White, Ekg Sarkisyan, R. Van Kooten, Kiyotomo Kawagoe, J. E. Pilcher, J. W. Gary, N. L. Rodning, D. S. Koetke, A. Macchiolo, J. von Krogh, S. W. O'Neale, J. Letts, Marcello Mannelli, R. Bartoldus, P. Dervan, J. Polok, D. Karlen, Alessandro Montanari, D. Glenzinski, H. Mes, I. P. Duerdoth, A. W. Lloyd, H. O. Ogren, K. J. Anderson, C. R. Jones, K. Stoll, Andris Skuja, S. Petzold, Dezso Horvath, M. J. Losty, M. Gruwé, D. I. Futyan, Christoph Geich-Gimbel, R. Howard, Jean-Arcady Meyer, G. W. Wilson, Tetsuro Mashimo, T. Kuhl, Richard Nisius, M. F. Turner-Watson, M. Hauschild, C. Markopoulos, F. Wäckerle, S. Braibant, A. Bellerive, B. List, Vakhtang Kartvelishvili, R. Mir, D. M. Gingrich, Randall Sobie, G. D. Lafferty, Marco Cuffiani, J. E. Conboy, A. Fürtjes, K. R. Hossain, W. Gorn, I. Cohen, R. Hawkings, Christoph Rembser, D. Lanske, A. Harel, P. Hüntemeyer, Ikuo Ueda, D. M. Strom, P. Scharff-Hansen, H. Landsman, D. R. Rust, A. M. Smith, Guenter Duckeck, M. Fierro, A. M. Lee, Richard Teuscher, A. S. Turcot, E. von Törne, F. Fiedler, M. Kolrep, F. G. Oakham, B. Schmitt, E. L. Barberio, N. Altekamp, H. Voss, R. J. Barlow, D. J. Miller, S. Spagnolo, S. Yamashita, P. Igo-Kemenes, M. Hoch, K. Ishii, H. Jeremie, O. Schaile, S. Robertson, Sven Menke, Ehud Duchovni, M. Jimack, A. Michelini, Satoshi Tanaka, T. Kobayashi, Peter R Hobson, J. M. Roney, R. L. Coxe, D. Zer-Zion, Sachio Komamiya, A. T. Watson, A. Hocker, Koichi Nagai, J. Schieck, D. Chrisman, G. D. Long, T. P. Kokott, W. Mohr, Volker Blobel, Achim Stahl, T. Saeki, R. Davis, Stephen Lloyd, J. Grunhaus, R. Kowalewski, S. Arcelli, F. Scharf, German Martinez, Juergen Thomas, A. Biguzzi, J. G. Layter, Gideon Alexander, M. A. Thomson, Paolo Capiluppi, P. E.L. Clarke, J. P. Martin, E. K. U. Gross, S. De Jong, H. Rick, M. Sproston, G. G. Hanson, G. Giacomelli, I. Lawson, K. Stephens, A. De Roeck, M. Kobel, C. Littlewood, M. S. Dixit, Frans Meijers, O. C. Cooke, P. Pfeifenschneider, V. Gibson, I. Trigger, D. R. Ward, J. Patt, André Schöning, O. Sahr, Satoshi Mihara, Otmar Biebel, Paolo Giacomelli, M. Hansroul, R. J. Homer, P. I. Kayal, Norbert Wermes, Sherry Towers, T. Kawamoto, W. R. Gibson, S. Orito, K. Harder, S. Betts, M. Hapke, M. J. Oreglia, J. R. Carter, G. N. Patrick, R. M. Brown, Lorne Levinson, C. Hartmann, D. E. Plane, G. M. Dallavalle, K. Roscoe, Klaus Kurt Desch, E. Torrence, E. Clay, and Raimund Ströhmer

Subjects
Nuclear physics, Physics, Nuclear and High Energy Physics, Electron energy spectrum, 010308 nuclear & particles physics, Branching fraction, Electron–positron annihilation, 0103 physical sciences, Strong coupling, Analytical chemistry, Mass scale, 010306 general physics, 01 natural sciences
Abstract

The branching ratio for the decay τ − → e − ν e ν τ has been measured using Z 0 decay data collected by the OPAL experiment at LEP. In total 33 073 τ − → e − ν e ν τ candidates were identified from a sample of 186 197 selected τ decays, giving a branching ratio of B (τ − → e − ν e ν τ )=(17.81±0.09 (stat) ±0.06 (syst) )% . This result is combined with other measurements to test e - μ and μ - τ universality in charged-current weak interactions. Additionally, the strong coupling constant α s ( m τ 2 ) has been extracted from B (τ − → e − ν e ν τ ) and evolved to the Z 0 mass scale, giving α s ( m Z 2 )=0.1204±0.0011 (exp)±0.0019 (theory).

Published
1999

37. Search for scalar top and scalar bottom quarks at $\sqrt{s}$ = 183 GeV at LEP

Author

S. Petzold, W. J. McDonald, B. C. Shen, Tetsuro Mashimo, Matthias Schröder, K. Nagai, K. Stephens, R. Bartoldus, Siegfried Bethke, A. K. Honma, W. G. Scott, M. Thiergen, I. Nakamura, H. O. Ogren, W. Gorn, Christoph Geich-Gimbel, D. R. Rust, D. Glenzinski, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, V. Gibson, A. M. Lee, E. von Törne, S. Yamashita, P. Igo-Kemenes, K. Ishii, H. Jeremie, Vakhtang Kartvelishvili, T. R. Junk, J. E. Conboy, A. Fürtjes, I. Trigger, D. R. Ward, T. Kress, R. W. Springer, R. Van Kooten, M. Boutemeur, F. S. Merritt, S. Braibant, Georges Azuelos, E. Tsur, A. D. Schaile, Gabriella Pasztor, J. Bechtluft, J. A. McKenna, O. Schaile, M. Verzocchi, K. W. Bell, S. B. Anderson, P. Szymanski, J. Pálinkás, M. Schumacher, F. Wäckerle, E. Lefebvre, G. Yekutieli, E. do Couto e Silva, S. Robertson, Gregor Herten, J. C. Hill, U. Jost, R. Mir, R. Hawkings, B. Wilkens, D. M. Gingrich, Sven Menke, J. Lauber, S. D. Talbot, D. Eatough, A. A. Carter, Ron Folman, F. Odorici, G. A. Snow, C. P. Ward, C. Hartmann, D. E. Plane, J. E. Pilcher, R. Lahmann, Stephen Hillier, Stan Bentvelsen, G. M. Dallavalle, S. Söldner-Rembold, L. Brigliadori, U. Müller, A. J. Martin, D. C. Imrie, P. Utzat, U. Ruppel, N. J. Oldershaw, John Allison, G. P. Siroli, P. G. Estabrooks, R. K. Keeler, M. R. Ingram, Christoph Schwick, H. M. Fischer, N. K. Watson, P. M. Watkins, W. R. Gibson, J. M. Roney, C. K. Hargrove, M. Fanti, B. T. Bouwens, Daniele Bonacorsi, R. G. Kellogg, James Pinfold, R. Perez-Ochoa, D. G. Fong, J. Gascon, J. Letts, Gideon Alexander, Paolo Capiluppi, Kiyotomo Kawagoe, Claire Shepherd-Themistocleous, R. M. Brown, Lorne Levinson, Csaba Hajdu, Robert McPherson, G. W. Wilson, P. S. Wells, V. Zacek, Richard Teuscher, Stefano Marcellini, A. Skillman, A. S. Turcot, M. Hauschild, K. Sachs, Mathieu Doucet, Tara Shears, R. D. Heuer, Fabrizio Fabbri, F. Fiedler, J. von Krogh, C. Markus, A. A. Faust, H. Mes, I. P. Duerdoth, Terry Richard Wyatt, Shlomo Dado, J. W. Gary, P. A. Hart, J. Schieck, D. S. Koetke, Stefan Kluth, Marcello Mannelli, Otmar Biebel, Silvia Arcelli, J. E. Bloomer, G. T. Jones, E. H. Vokurka, K. R. Hossain, T. Behnke, Satoshi Mihara, L. A. del Pozo, P. Scharff-Hansen, W. Mohr, Shlomit Tarem, S. Baumann, P. Hüntemeyer, Reda Tafirout, Klaus Kurt Desch, T. J. McMahon, M. J. Pearce, F. G. Oakham, Giora Mikenberg, B. Schmitt, M. Kolrep, B. Stockhausen, Paul Kyberd, E. A. Mckigney, A. Macchiolo, E. L. Barberio, R. K. Carnegie, A. Posthaus, D. Chrisman, G. D. Long, F. K. Loebinger, Hans-Christian Schultz-Coulon, M. Herndon, Volker Blobel, Randall Sobie, M. Gruwé, M. Bobinski, P. I. Kayal, G. D. Lafferty, C. M. Hawkes, W. P. Lai, J. A. Wilson, A. M. Smith, C. Dallapiccola, J. Steuerer, Ivor Fleck, Richard Nisius, S. W. O'Neale, Guenter Duckeck, D. M. Strom, K. J. Anderson, Marco Cuffiani, Joleen Pater, Norbert Wermes, Sherry Towers, T. Kawamoto, D. Lazic, M. A. Thomson, A. Klier, E. K. U. Gross, N. Altekamp, H. Voss, Stephen Lloyd, R. Rylko, R. Giacomelli, S. Orito, O. C. Cooke, P. Pfeifenschneider, M. Sproston, D. I. Futyan, R. J. Barlow, D. J. Miller, J. Goldberg, M. Hapke, B. Nellen, A. Oh, A. Macpherson, N. I. Geddes, Michael Hildreth, J. Patt, P. Poffenberger, D. E. Hutchcroft, André Schöning, Ehud Duchovni, N. L. Rodning, M. J. Oreglia, H. G. Evans, B. Poli, M. J. Goodrick, R. Howard, J. S. White, I. Cohen, S. A. Robins, D. L. Rees, J. R. Carter, G. N. Patrick, M. Jimack, Paolo Giacomelli, M. Hansroul, Gunter Wolf, K. Ackerstaff, D. Rigby, R. J. Hemingway, A. Joly, F. Scharf, German Martinez, Beatrix Dienes, S. M. Gascon-Shotkin, C. Burgard, C. Sbarra, R. J. Homer, A. Michelini, Matthew Evans, A. M. Rossi, C. Y. Chang, P. Taras, Michael Kobel, Allen Mincer, Satoshi Tanaka, T. Kobayashi, B. W. Kennedy, Julie Kirk, Ekg Sarkisyan, P. Jovanovic, P. W. Jeffreys, Austin Ball, Peter Krieger, P. Vikas, Alessandro Montanari, D. Lanske, M. Fierro, J. E.G. Edwards, S. R. Lautenschlager, H. A. Neal, O. Runolfsson, C. Beeston, Claudio Grandi, G. G. Hanson, G. Giacomelli, M. S. Dixit, Frans Meijers, A. Biguzzi, A. Rooke, J. G. Layter, P. E.L. Clarke, M. K. Jones, J. P. Martin, S. De Jong, A. N. Bell, P. Gagnon, A. Sittler, Peter Schleper, Zoltan Laszlo Trocsanyi, S. D. Bird, P. Schenk, D. Axen, A. Jawahery, Peter Sherwood, Alexander Wagner, J. Ludwig, K. Runge, P. Bock, Gideon Bella, H. J. Burckhart, Jacqueline Batley, Sachio Komamiya, Theodoros Geralis, E. Ros, A. T. Watson, I. J. Bloodworth, C. R. Jones, T. P. Kokott, Dave Charlton, R. Bürgin, T. Saeki, Yoram Rozen, R. Davis, M. Foucher, J. Grunhaus, D. Karlen, M. F. Turner-Watson, M. Morii, Peter R Hobson, Stefan Schmitt, D. Zer-Zion, P. Routenburg, P. Mättig, Shoji Asai, Daniel Lellouch, Takehiko Mori, K. Stoll, and Andris Skuja

Subjects
Physics, Stop squark, Top quark, Particle physics, Physics and Astronomy (miscellaneous), High Energy Physics::Lattice, High Energy Physics::Phenomenology, Top quark condensate, Bottom quark, Nuclear physics, Quark star, Neutralino, Up quark, High Energy Physics::Experiment, B meson, Nuclear Experiment, Engineering (miscellaneous), Particle Physics - Experiment
Abstract

Searches for a scalar top quark and a scalar bottom quark have been performed using a total data sample of 56.8 pb-1 at a centre-of-mass energy of 183 GeV collected with the OPAL detector at LEP. No candidate events were observed. Combining this result with those obtained at lower centre-of-mass energies, the 95% C.L. lower limit on the scalar top quark mass is 85.0 GeV if the mixing angle between the supersymmetric partners of the left- and right-handed states of the top quark is zero. The lower limit is 81.3 GeV, even if the scalar top quark decouples from the Z boson. These limits were obtained assuming that the scalar top quark decays into a charm quark and the lightest neutralino, and that the mass difference between the scalar top quark and the lightest neutralino is larger than 10 GeV. Assuming a relatively light scalar neutrino, The complementary decay mode of the scalar top quark in which it decays into a bottom quark, a charged lepton and a scalar neutrino was also studied. From a similar analysis, a mass limit on the light scalar bottom quark was set at 82.7 GeV for a mass difference between the scalar bottom quark and the lightest neutralino larger than 7 GeV, and at 84.0 GeV for the mass difference larger 10 GeV and the lightest neutralino heavier than 30 GeV. These limits were obtained assuming that the scalar bottom quark decays into a bottom quark and the lightest neutralino, and that a mixing angle between the supersymmetric partners of the left- and right-handed states of the bottom quark is zero. Searches for a scalar top quark and a scalar bottom quark have been performed using a total data sample of 56.8 pb-1 at a centre-of-mass energy of 183 GeV collected with the OPAL detector at LEP. No candidate events were observed. Combining this result with those obtained at lower centre-of-mass energies, the 95% C.L. lower limit on the scalar top quark mass is 85.0 GeV if the mixing angle between the supersymmetric partners of the left- and right-handed states of the top quark is zero. The lower limit is 81.3 GeV, even if the scalar top quark decouples from the Z boson. These limits were obtained assuming that the scalar top quark decays into a charm quark and the lightest neutralino, and that the mass difference between the scalar top quark and the lightest neutralino is larger than 10 GeV. Assuming a relatively light scalar neutrino, The complementary decay mode of the scalar top quark in which it decays into a bottom quark, a charged lepton and a scalar neutrino was also studied. From a similar analysis, a mass limit on the light scalar bottom quark was set at 82.7 GeV for a mass difference between the scalar bottom quark and the lightest neutralino larger than 7 GeV, and at 84.0 GeV for the mass difference larger 10 GeV and the lightest neutralino heavier than 30 GeV. These limits were obtained assuming that the scalar bottom quark decays into a bottom quark and the lightest neutralino, and that a mixing angle between the supersymmetric partners of the left- and right-handed states of the bottom quark is zero.

Published
1999

39. Multi-photon production in e+e− collisions at =183 GeV

Author

K. Ackerstaff, G. Alexander, J. Allison, N. Altekamp, K.J. Anderson, S. Anderson, S. Arcelli, S. Asai, S.F. Ashby, D. Axen, G. Azuelos, A.H. Ball, E. Barberio, R.J. Barlow, R. Bartoldus, J.R. Batley, S. Baumann, J. Bechtluft, T. Behnke, K.W. Bell, G. Bella, S. Bentvelsen, S. Bethke, S. Betts, O. Biebel, A. Biguzzi, S.D. Bird, V. Blobel, I.J. Bloodworth, M. Bobinski, P. Bock, J. Böhme, M. Boutemeur, S. Braibant, P. Bright-Thomas, R.M. Brown, H.J. Burckhart, C. Burgard, R. Bürgin, P. Capiluppi, R.K. Carnegie, A.A. Carter, J.R. Carter, C.Y. Chang, D.G. Charlton, D. Chrisman, C. Ciocca, P.E.L. Clarke, E. Clay, I. Cohen, J.E. Conboy, O.C. Cooke, C. Couyoumtzelis, R.L. Coxe, M. Cuffiani, S. Dado, G.M. Dallavalle, R. Davis, S. De Jong, L.A. del Pozo, A. de Roeck, K. Desch, B. Dienes, M.S. Dixit, M. Doucet, J. Dubbert, E. Duchovni, G. Duckeck, I.P. Duerdoth, D. Eatough, P.G. Estabrooks, E. Etzion, H.G. Evans, F. Fabbri, A. Fanfani, M. Fanti, A.A. Faust, F. Fiedler, M. Fierro, H.M. Fischer, I. Fleck, R. Folman, A. Fürtjes, D.I. Futyan, P. Gagnon, J.W. Gary, J. Gascon, S.M. Gascon-Shotkin, C. Geich-Gimbel, T. Geralis, G. Giacomelli, P. Giacomelli, V. Gibson, W.R. Gibson, D.M. Gingrich, D. Glenzinski, J. Goldberg, W. Gorn, C. Grandi, E. Gross, J. Grunhaus, M. Gruwé, G.G. Hanson, M. Hansroul, M. Hapke, C.K. Hargrove, C. Hartmann, M. Hauschild, C.M. Hawkes, R. Hawkings, R.J. Hemingway, M. Herndon, G. Herten, R.D. Heuer, M.D. Hildreth, J.C. Hill, S.J. Hillier, P.R. Hobson, A. Hocker, R.J. Homer, A.K. Honma, D. Horváth, K.R. Hossain, R. Howard, P. Hüntemeyer, P. Igo-Kemenes, D.C. Imrie, K. Ishii, F.R. Jacob, A. Jawahery, H. Jeremie, M. Jimack, A. Joly, C.R. Jones, P. Jovanovic, T.R. Junk, D. Karlen, V. Kartvelishvili, K. Kawagoe, T. Kawamoto, P.I. Kayal, R.K. Keeler, R.G. Kellogg, B.W. Kennedy, A. Klier, S. Kluth, T. Kobayashi, M. Kobel, D.S. Koetke, T.P. Kokott, M. Kolrep, S. Komamiya, R.V. Kowalewski, T. Kress, P. Krieger, J. von Krogh, P. Kyberd, G.D. Lafferty, D. Lanske, J. Lauber, S.R. Lautenschlager, I. Lawson, J.G. Layter, D. Lazic, A.M. Lee, E. Lefebvre, D. Lellouch, J. Letts, L. Levinson, R. Liebisch, B. List, C. Littlewood, A.W. Lloyd, S.L. Lloyd, F.K. Loebinger, G.D. Long, M.J. Losty, J. Ludwig, D. Liu, A. Macchiolo, A. Macpherson, M. Mannelli, S. Marcellini, C. Markopoulos, A.J. Martin, J.P. Martin, G. Martinez, T. Mashimo, P. Mättig, W.J. McDonald, J. McKenna, E.A. Mckigney, T.J. McMahon, R.A. McPherson, F. Meijers, S. Menke, F.S. Merritt, H. Mes, J. Meyer, A. Michelini, S. Mihara, G. Mikenberg, D.J. Miller, R. Mir, W. Mohr, A. Montanari, T. Mori, K. Nagai, I. Nakamura, H.A. Neal, B. Nellen, R. Nisius, S.W. O'Neale, F.G. Oakham, F. Odorici, H.O. Ogren, M.J. Oreglia, S. Orito, J. Pálinkás, G. Pásztor, J.R. Pater, G.N. Patrick, J. Patt, R. Perez-Ochoa, S. Petzold, P. Pfeifenschneider, J.E. Pilcher, J. Pinfold, D.E. Plane, P. Poffenberger, B. Poli, J. Polok, M. Przybycień, C. Rembser, H. Rick, S. Robertson, S.A. Robins, N. Rodning, J.M. Roney, K. Roscoe, A.M. Rossi, Y. Rozen, K. Runge, O. Runolfsson, D.R. Rust, K. Sachs, T. Saeki, O. Sahr, W.M. Sang, E.K.G. Sarkisyan, C. Sbarra, A.D. Schaile, O. Schaile, F. Scharf, P. Scharff-Hansen, J. Schieck, B. Schmitt, S. Schmitt, A. Schöning, T. Schorner, M. Schröder, M. Schumacher, C. Schwick, W.G. Scott, R. Seuster, T.G. Shears, B.C. Shen, C.H. Shepherd-Themistocleous, P. Sherwood, G.P. Siroli, A. Sittler, A. Skuja, A.M. Smith, G.A. Snow, R. Sobie, S. Söldner-Rembold, M. Sproston, A. Stahl, K. Stephens, J. Steuerer, K. Stoll, D. Strom, R. Ströhmer, R. Tafirout, S.D. Talbot, S. Tanaka, P. Taras, S. Tarem, R. Teuscher, M. Thiergen, M.A. Thomson, E. von Törne, E. Torrence, S. Towers, I. Trigger, Z. Trócsányi, E. Tsur, A.S. Turcot, M.F. Turner-Watson, R. Van Kooten, P. Vannerem, M. Verzocchi, P. Vikas, H. Voss, F. Wäckerle, A. Wagner, C.P. Ward, D.R. Ward, P.M. Watkins, A.T. Watson, N.K. Watson, P.S. Wells, N. Wermes, J.S. White, G.W. Wilson, J.A. Wilson, T.R. Wyatt, S. Yamashita, G. Yekutieli, V. Zacek, and D. Zer-Zion

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Luminosity (scattering theory), Photon, 010308 nuclear & particles physics, Branching fraction, Astrophysics::High Energy Astrophysical Phenomena, Resonance, Lambda, 01 natural sciences, 7. Clean energy, Excited state, 0103 physical sciences, High Energy Physics::Experiment, Invariant mass, 010306 general physics, Energy (signal processing)
Abstract

The process e+e- to gamma gamma (gamma) is studied using data recorded with the OPAL detector at LEP. The data sample corresponds to a total integrated luminosity of 56.2 pb-1 taken at a centre-of-mass energy of 183 GeV. The measured cross-section agrees well with the expectation from QED. A fit to the angular distribution is used to obtain improved limits at 95% CL on the QED cut-off parameters: Lambda+ > 233 GeV and Lambda- > 265 GeV as well as a mass limit for an excited electron, M(e*) > 227 GeV assuming equal e*egamma and eegamma couplings. No evidence for resonance production is found in the invariant mass spectrum of photon pairs. Limits are obtained for the cross-section times branching ratio for a resonance decaying into two photons.

Published
1998

40. Investigation of CP violation in $\mathrm{B^0} \rightarrow \mathrm{J}/\psi \mathrm{K^0_S}$ decays at LEP

Author

G. W. Wilson, Richard Teuscher, A. S. Turcot, M. Hauschild, C. Markopoulos, F. Fiedler, A. Biguzzi, A. Rooke, R. Bartoldus, A. Macpherson, C. Markus, I. J. Bloodworth, J. G. Layter, H. O. Ogren, R. Kowalewski, Christoph Geich-Gimbel, Yoram Rozen, M. Foucher, R. Davis, E. H. Vokurka, M. Kolrep, K. Stephens, H. M. Fischer, R. Howard, J. S. White, Gideon Alexander, Junichi Kanzaki, D. Karlen, M. Schumacher, E. Lefebvre, Paolo Capiluppi, P. G. Estabrooks, R. K. Keeler, A. Michelini, Vakhtang Kartvelishvili, P. Gagnon, F. Odorici, M. Fierro, V. Gibson, Randall Sobie, N. K. Watson, P. M. Watkins, Daniel Lellouch, J. E. Conboy, A. Fürtjes, J. Letts, S. R. Lautenschlager, G. D. Lafferty, Stefan Schmitt, L. Brigliadori, Shoji Asai, Takehiko Mori, R. W. Springer, P. Mättig, V. Zacek, A. Sittler, T. R. Junk, H. A. Neal, Lutz Feld, G. G. Hanson, Peter Schleper, I. Trigger, O. Runolfsson, K. Sachs, Zoltan Laszlo Trocsanyi, R. L. Coxe, D. R. Ward, T. Kress, John Allison, Shlomo Dado, N. J. Oldershaw, C. Dallapiccola, J. Goldberg, Silvia Arcelli, G. Giacomelli, I. Lawson, U. Ruppel, A. Hocker, D. Chrisman, G. D. Long, Volker Blobel, M. Boutemeur, F. S. Merritt, Matthias Schröder, B. Nellen, S. Yamashita, P. Igo-Kemenes, Guenter Duckeck, A. De Roeck, K. Ishii, H. Jeremie, P. Scharff-Hansen, Claudio Grandi, P. S. Wells, M. F. Turner-Watson, Peter R Hobson, S. W. O'Neale, M. S. Dixit, Frans Meijers, Georges Azuelos, E. Tsur, Stephen Lloyd, M. Thiergen, Giora Mikenberg, Terry Richard Wyatt, S. F. Ashby, K. J. Anderson, M. Verzocchi, K. W. Bell, Ekg Sarkisyan, S. D. Bird, J. Pálinkás, S. B. Anderson, S. M. Gascon-Shotkin, P. Szymanski, R. G. Kellogg, D. Zer-Zion, S. Baumann, E. A. Mckigney, Raimund Ströhmer, P. Routenburg, P. W. Jeffreys, J. Bechtluft, J. A. McKenna, Ehud Duchovni, J. C. Hill, O. Schaile, M. Jimack, P. E.L. Clarke, M. K. Jones, J. P. Martin, W. P. Lai, H. G. Evans, A. M. Smith, Csaba Hajdu, M. J. Goodrick, I. Cohen, S. Robertson, P. Poffenberger, J. M. Roney, S. De Jong, D. I. Futyan, W. J. McDonald, Stefano Marcellini, Gregor Herten, B. C. Shen, A. D. Schaile, Gabriella Pasztor, P. Vannerem, D. Lui, Anna Macchiolo, Stan Bentvelsen, Christoph Rembser, Satoshi Mihara, J. Grunhaus, D. Axen, Ikuo Ueda, D. M. Strom, Sven Menke, A. Jawahery, N. Altekamp, H. Voss, P. Vikas, T. Kobayashi, Siegfried Bethke, A. K. Honma, K. Stoll, Matthew Evans, A. M. Rossi, G. A. Snow, C. P. Ward, D. Lanske, W. M. Sang, W. G. Scott, J. E. Pilcher, I. Nakamura, S. Söldner-Rembold, A. J. Martin, Andris Skuja, Beatrix Dienes, R. J. Barlow, S. Petzold, Sachio Komamiya, R VanKooten, Theodoros Geralis, Peter Sherwood, Erez Etzion, C. Y. Chang, C. K. Hargrove, D. Glenzinski, A. T. Watson, Tara Shears, Tetsuro Mashimo, P. Taras, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, P. A. Hart, Michael Kobel, D. J. Miller, T. P. Kokott, A. Joly, Stefan Kluth, Shlomit Tarem, Allen Mincer, Marcello Fanti, T. Saeki, Alexander Wagner, J. Ludwig, Julie Kirk, K. Runge, P. Bock, Alessandra Fanfani, N. I. Geddes, Michael Hildreth, C. Sbarra, J. Lauber, N. L. Rodning, B. Poli, W. Gorn, B. Stockhausen, Paul Kyberd, F. K. Loebinger, U. Jost, S. A. Robins, R. Mir, J. Steuerer, Ivor Fleck, R. Hawkings, Joleen Pater, A. Klier, S. D. Talbot, R. Giacomelli, A. Oh, K. Ackerstaff, D. Eatough, James Pinfold, R. Perez-Ochoa, D. G. Fong, F. G. Oakham, B. Schmitt, J. Gascon, E. L. Barberio, Paolo Giacomelli, M. Hansroul, R. J. Hemingway, B. W. Kennedy, C. Burgard, P. Jovanovic, Austin Ball, Peter Krieger, Alessandro Montanari, R. J. Homer, J. W. Gary, D. S. Koetke, O. C. Cooke, P. Pfeifenschneider, Marcello Mannelli, J. Patt, André Schöning, O. Sahr, M. A. Thomson, H. Mes, I. P. Duerdoth, S. Braibant, P. Hüntemeyer, E. K. U. Gross, M. Sproston, C. Hartmann, D. E. Plane, Stephen Hillier, G. M. Dallavalle, Reda Tafirout, Klaus Kurt Desch, E. Torrence, W. R. Gibson, T. J. McMahon, C. Couyoumtzelis, R. M. Brown, Lorne Levinson, A. Skillman, R. K. Carnegie, M. Herndon, M. Bobinski, J. A. Wilson, F. Scharf, T. Behnke, C. M. Hawkes, German Martinez, Richard Nisius, B. List, D. Lazic, Marco Cuffiani, Dave Charlton, Daniele Bonacorsi, Claire Shepherd-Themistocleous, F. Wäckerle, D. M. Gingrich, J. von Krogh, R. Bürgin, A. A. Faust, M. Gruwé, L. A. del Pozo, G. Yekutieli, Robert McPherson, Mathieu Doucet, R. D. Heuer, A. A. Carter, Ron Folman, Fabrizio Fabbri, K. Nagai, P. Utzat, D. R. Rust, Gideon Bella, J. Schieck, A. M. Lee, E. von Törne, H. J. Burckhart, Jacqueline Batley, W. Mohr, A. Posthaus, C. R. Jones, R. Lahmann, D. C. Imrie, G. P. Siroli, Otmar Biebel, Christoph Schwick, P. I. Kayal, Kiyotomo Kawagoe, Norbert Wermes, Sherry Towers, T. Kawamoto, S. Orito, K. R. Hossain, S. Betts, M. Hapke, D. E. Hutchcroft, M. J. Oreglia, J. R. Carter, and G. N. Patrick

Subjects
Physics, Nuclear physics, Particle physics, Physics and Astronomy (miscellaneous), media_common.quotation_subject, Electron–positron annihilation, Hadron, Detector, CP violation, Engineering (miscellaneous), Asymmetry, media_common, Standard Model
Abstract

An investigation of CP violation was performed using a total of 24 candidates for B0→J/ψK0SB0→J/ψKS0 decay, with a purity of about 60%. These events were selected from 4.4 million hadronic Z0Z0 decays recorded by the OPAL detector at LEP. An analysis procedure, involving techniques to reconstruct the proper decay times and tag the produced b-flavours, B0B0 or B¯0B¯0 , has been developed to allow a first direct study of the time dependent CP asymmetry that, in the Standard Model, is sin2βsin⁡2β . The result is where the first error is statistical and the second systematic. This result is used to determine probabilities for different values of sin2βsin⁡2β in the physical region from −1−1 to +1.

Published
1998

41. Determination of the production rate of D*0 mesons and of the ratio V/(V+P) in $$Z^0 \to c\bar c$$ decays

Author

K. Ackerstaff, G. Alexander, J. Allison, N. Altekamp, K. J. Anderson, S. Anderson, S. Arcelli, S. Asai, S. F. Ashby, D. Axen, G. Azuelos, A. H. Ball, E. Barberio, R. J. Barlow, R. Bartoldus, J. R. Batley, S. Baumann, J. Bechtluft, T. Behnke, K. W. Bell, G. Bella, S. Bentvelsen, S. Bethke, S. Betts, O. Biebel, A. Biguzzi, S. D. Bird, V. Blobel, I. J. Bloodworth, M. Bobinski, P. Bock, D. Bonacorsi, M. Boutemeur, S. Braibant, L. Brigliadori, R. M. Brown, H. J. Burckhart, C. Burgard, R. Bürgin, P. Capiluppi, R. K. Carnegie, A. A. Carter, J. R.Carter, C. Y. Chang, D. G. Charlton, D. Chrisman, P. E. L. Clarke, I. Cohen, J. E. Conboy, O. C. Cooke, C. Couyoumtzelis, R. L. Coxe, M. Cuffiani, S. Dado, C. Dallapiccola, G. M. Dallavalle, R. Davis, S. De Jong, L. A. del Pozo, A. de Roeck, K. Desch, B. Dienes, M. S. Dixit, M. Doucet, E. Duchovni, G. Duckeck, I. P. Duerdoth, D. Eatough, P. G. Estabrooks, E. Etzion, H. G. Evans, M. Evans, F. Fabbri, A. Fanfani, M. Fanti, A. A. Faust, L. Feld, F. Fiedler, M. Fierro, H. M. Fischer, I. Fleck, R. Folman, D. G. Fong, M. Foucher, A. Fürtjes, D. I. Futyan, P. Gagnon, J. W. Gary, J. Gascon, S. M. Gascon-Shotkin, N. I. Geddes, C. Geich-Gimbel, T. Geralis, G. Giacomelli, P. Giacomelli, R. Giacomelli, V. Gibson, W. R. Gibson, D. M. Gingrich, D. Glenzinski, J. Goldberg, M. J. Goodrick, W. Gorn, C. Grandi, E. Gross, J. Grunhaus, M. Gruwé, C. Hajdu, G. G. Hanson, M. Hansroul, M. Hapke, C. K. Hargrove, P. A. Hart, C. Hartmann, M. Hauschild, C. M. Hawkes, R. Hawkings, R. J. Hemingway, M. Herndon, G. Herten, R. D. Heuer, M. D. Hildreth, J. C. Hill, S. J. Hillier, P. R. Hobson, A. Hocker, R. J. Homer, A. K. Honma, D. Horvath, K. R. Hossain, R. Howard, P. Hüntemeyer, D. E. Hutchcroft, P. Igo-Kemenes, D. C. Imrie, K. Ishii, A. Jawahery, P. W. Jeffreys, H. Jeremie, M. Jimack, A. Joly, C. R. Jones, M. Jones, U. Jost, P. Jovanovic, T. R. Junk, J. Kanzaki, D. Karlen, V. Kartvelishvili, K. Kawagoe, T. Kawamoto, P. I. Kayal, R. K. Keeler, R. G. Kellogg, B. W. Kennedy, J. Kirk, A. Klier, S. Kluth, T. Kobayashi, M. Kobel, D. S. Koetke, T. P. Kokott, M. Kolrep, S. Komamiya, R. V. Kowalewski, T. Kress, P. Krieger, J. von Krogh, P. Kyberd, G. D. Lafferty, R. Lahmann, W. P. Lai, D. Lanske, J. Lauber, S. R. Lautenschlager, I. Lawson, J. G. Layter, D. Lazic, A. M. Lee, E. Lefebvre, D. Lellouch, J. Letts, L. Levinson, B. List, S. L. Lloyd, F. K. Loebinger, G. D. Long, M. J. Losty, J. Ludwig, D. Lui, A. Macchiolo, A. Macpherson, M. Mannelli, S. Marcellini, C. Markopoulos, C. Markus, A. J. Martin, J. P. Martin, G. Martinez, T. Mashimo, P. Mättig, W. J. McDonald, J. McKenna, E. A. Mckigney, T. J. McMahon, R. A. McPherson, F. Meijers, S. Menke, F. S. Merritt, H. Mes, J. Meyer, A. Michelini, S. Mihara, G. Mikenberg, D. J. Miller, A. Mincer, R. Mir, W. Mohr, A. Montanari, T. Mori, K. Nagai, I. Nakamura, H. A. Neal, B. Nellen, R. Nisius, S. W. O’Neale, F. G. Oakham, F. Odorici, H. O. Ogren, A. Oh, N. J. Oldershaw, M. J. Oreglia, S. Orito, J. Pálinkás, G. Pásztor, J. R. Pater, G. N. Patrick, J. Patt, R. Perez-Ochoa, S. Petzold, P. Pfeifenschneider, J. E. Pilcher, J. Pinfold, D. E. Plane, P. Poffenberger, B. Poli, A. Posthaus, C. Rembser, S. Robertson, S. A. Robins, N. Rodning, J. M. Roney, A. Rooke, A. M. Rossi, P. Routenburg, Y. Rozen, K. Runge, O. Runolfsson, U. Ruppel, D. R. Rust, K. Sachs, T. Saeki, O. Sahr, W. M. Sang, E. K. G. Sarkisyan, C. Sbarra, A. D. Schaile, O. Schaile, F. Scharf, P. Scharff-Hansen, J. Schieck, P. Schleper, B. Schmitt, S. Schmitt, A. Schöming, M. Schröder, M. Schumacher, C. Schwick, W. G. Scott, T. G. Shears, B. C. Shen, C. H. Shepherd-Themistocleous, P. Sherwood, G. P. Siroli, A. Sittler, A. Skillman, A. Skuja, A. M. Smith, G. A. Snow, R. Sobie, S. Söldner-Rembold, R. W. Springer, M. Sproston, K. Stephens, J. Steuerer, B. Stockhausen, K. Stoll, D. Strom, R. Ströhmer, P. Szymanski, R. Tafirout, S. D. Talbot, P. Taras, S. Tarem, R. Teuscher, M. Thiergen, M. A. Thomson, E. von Törne, E. Torrence, S. Towers, I. Trigger, Z. Trócsányi, E. Tsur, A. S. Turcot, M. F. Turner-Watson, I. Ueda, P. Utzat, R. Van Kooten, P. Vannerem, M. Verzocchi, P. Vikas, E. H. Vokurka, H. Voss, F. Wäckerle, A. Wagner, C. P. Ward, D. R. Ward, P. M. Watkins, A. T. Watson, N. K. Watson, P. S. Wells, N. Wermes, J. S. White, G. W. Wilson, J. A. Wilson, T. R. Wyatt, S. Yamashita, G. Yekutieli, V. Zacek, and D. Zer-Zion

Subjects
Systematic error, Physics, Particle physics, Annihilation, Physics and Astronomy (miscellaneous), Meson, Electron–positron annihilation, High Energy Physics::Phenomenology, Hadron, Nuclear physics, Pseudoscalar, Excited state, High Energy Physics::Experiment, Nuclear Experiment, Engineering (miscellaneous), Production rate
Abstract

In e+e2212 collisions at centre-of-mass energies around 91 GeV, D*0 mesons have been reconstructed using data collected with the OPAL detector at LEP. The hadronisation fraction has been measured to be f(c→D*0)=0.218±0.054±0.045±0.007, where the errors correspond to the statistical and systematic errors specific to this analysis, and to systematic uncertainties from externally measured branching fractions, respectively. Together with previous OPAL measurements of the hadronisation fractions of other charmed mesons, this value is used to investigate the relative production of observed vector and pseudoscalar charmed mesons in \(Z^0 \to c\bar c\) decays. The production ratio is determined to be PeffV = V/(V+P)=0.57±0.05. The relative primary production of vector and pseudoscalar mesons, Pvrim, is studied in the context of the production and decay of orbitally excited charmed resonances. The first measurement of the inclusive Ds*+ production rate in hadronic Z0 decays is presented.

Published
1998

42. An upper limit for the $\tau$ –neutrino mass from $\tau\rightarrow 5\pi^{\pm}\nu_{\tau}$ decays

Author

R. Bartoldus, H. M. Fischer, H. O. Ogren, Christoph Geich-Gimbel, P. G. Bright-Thomas, N. Altekamp, H. Voss, Gideon Bella, M. Schumacher, E. Lefebvre, S. B. Anderson, D. J. Miller, Vakhtang Kartvelishvili, S. L. Lloyd, F. Odorici, Otmar Biebel, P. I. Kayal, A. J. Martin, Norbert Wermes, Sherry Towers, T. Kawamoto, J. E. Conboy, A. Fürtjes, S. Orito, H. A. Neal, B. C. Shen, S. W. O'Neale, H. J. Burckhart, Jacqueline Batley, Stan Bentvelsen, J. A. McKenna, Daniel Lellouch, Takehiko Mori, J. Grunhaus, P. Gagnon, J. Allison, Siegfried Bethke, A. K. Honma, W. G. Scott, I. Nakamura, Silvia Arcelli, R. J. Hemingway, B. W. Kennedy, P. Jovanovic, P. Mättig, R. Kowalewski, Austin Ball, Peter Krieger, C. K. Hargrove, Claudia Ciocca, M. Boutemeur, F. S. Merritt, Alessandro Montanari, S. A. Robins, H. Mes, I. P. Duerdoth, A. Sittler, R. Mir, Zoltan Laszlo Trocsanyi, Matthias Schröder, J. W. Gary, K. J. Anderson, R. Hawkings, Raimund Ströhmer, J. R. Carter, P. Igo-Kemenes, T. Schorner, M. Thiergen, S. Braibant, Gideon Alexander, Paolo Capiluppi, S. Baumann, K. Ishii, H. Jeremie, S. Betts, M. Hapke, Stefan Schmitt, J. Bechtluft, R. Liebisch, K. Ackerstaff, E. A. Mckigney, James Pinfold, R. Perez-Ochoa, R. Seuster, M. J. Oreglia, G. Duckeck, C. R. Jones, F. G. Oakham, D. Glenzinski, B. Schmitt, E. L. Barberio, G. N. Patrick, G. Mikenberg, P. Hüntemeyer, J. Gascon, V. Gibson, O. Schaile, Dezso Horvath, M. J. Losty, Ehud Duchovni, R. J. Barlow, Jean-Arcady Meyer, A. D. Schaile, Gabriella Pasztor, V. Zacek, K. Roscoe, W.J. McDonald, J. Lauber, S. Robertson, M. F. Turner-Watson, F. Scharf, M. Fierro, M. Jimack, Ekg Sarkisyan, R. G. Kellogg, T. Kobayashi, P. Vannerem, German Martinez, N. K. Watson, Tara Shears, D. Lui, S. M. Gascon-Shotkin, Shoji Asai, A. Michelini, Beatrix Dienes, Peter R Hobson, D. S. Koetke, Reda Tafirout, Klaus Kurt Desch, G. D. Lafferty, D. I. Futyan, Sven Menke, Marcello Mannelli, I. J. Bloodworth, E. Torrence, Richard Teuscher, A. S. Turcot, Dave Charlton, D. Zer-Zion, K. Stoll, G. A. Snow, Andris Skuja, J. Goldberg, Claire Shepherd-Themistocleous, Stefano Marcellini, F. Fiedler, B. Nellen, C. P. Ward, S. D. Talbot, S. Petzold, C. Y. Chang, E. Clay, Sachio Komamiya, R. L. Coxe, M. Przybzien, M. A. Thomson, Theodoros Geralis, G. W. Wilson, P. G. Estabrooks, R. K. Keeler, W. M. Sang, S. Söldner-Rembold, Tetsuro Mashimo, Yoram Rozen, P. Taras, A. Hocker, R. Bürgin, P. Vikas, E. K. U. Gross, D. Eatough, D. Chrisman, G. D. Long, D. Lanske, J. Letts, A. A. Faust, W. R. Gibson, Volker Blobel, S. R. Lautenschlager, M. Sproston, T. P. Kokott, P. M. Watkins, H. G. Evans, M. Kolrep, W. Gorn, T. Saeki, S. D. Bird, I. Cohen, Georges Azuelos, T. Behnke, E. Tsur, J. Polok, A. Joly, D. Karlen, O. Runolfsson, Christoph Rembser, Alessandra Fanfani, D. Axen, R. Davis, Satoru Yamashita, M. Verzocchi, K. W. Bell, A. M. Rossi, K. Sachs, Shlomo Dado, A. Jawahery, A. Macchiolo, Claudio Grandi, P. Scharff-Hansen, J. Pálinkás, R. M. Brown, C. M. Hawkes, C. Sbarra, Lorne Levinson, Stefan Kluth, Peter Sherwood, Alexander Wagner, Shlomit Tarem, J. M. Roney, J. C. Hill, F. R. Jacob, J. Ludwig, K. Runge, Richard Nisius, A. M. Smith, P. Bock, B. List, Marco Cuffiani, S. F. Ashby, J. Schieck, W. Mohr, C. Hartmann, D. E. Plane, Stephen Hillier, Paul Kyberd, F. K. Loebinger, G. M. Dallavalle, Michael Hildreth, J. Steuerer, Ivor Fleck, N. L. Rodning, B. Poli, Joleen Pater, A. Klier, P. Poffenberger, Satoshi Mihara, K. Stephens, C. Littlewood, G. Yekutieli, T. R. Junk, I. Trigger, D. R. Ward, T. Kress, A. A. Carter, Ron Folman, T. J. McMahon, C. Couyoumtzelis, J. Dubbert, R. K. Carnegie, M. Herndon, M. Bobinski, J. A. Wilson, J. Böhme, P. E.L. Clarke, J. P. Martin, D. Lazic, S. De Jong, H. Rick, J. von Krogh, M. Gruwé, L. A. del Pozo, G. G. Hanson, G. Giacomelli, I. Lawson, A. De Roeck, M. Kobel, M. S. Dixit, Frans Meijers, O. C. Cooke, P. Pfeifenschneider, J. Patt, André Schöning, O. Sahr, A. Biguzzi, J. G. Layter, Paolo Giacomelli, M. Hansroul, C. Burgard, R. J. Homer, Achim Stahl, Kiyotomo Kawagoe, R. Van Kooten, K. R. Hossain, D. C. Imrie, G. P. Siroli, Christoph Schwick, F. Wäckerle, D. M. Gingrich, D. M. Strom, M. Fanti, Robert McPherson, Mathieu Doucet, R. D. Heuer, Fabrizio Fabbri, K. Nagai, Shigenori Tanaka, D. R. Rust, A. M. Lee, E. von Törne, P. S. Wells, Terry Richard Wyatt, A. T. Watson, A. Macpherson, R. J. Sobie, R. Howard, J. S. White, Gregor Herten, J. E. Pilcher, A. W. Lloyd, M. Hauschild, and C. Markopoulos

Subjects
Physics, Particle physics, Energy distribution, Physics and Astronomy (miscellaneous), High Energy Physics::Phenomenology, Particle identification, Nuclear physics, Tau neutrino, Pi, High Energy Physics::Experiment, Invariant mass, Limit (mathematics), Engineering (miscellaneous), ALEPH experiment
Abstract

An upper limit for the \(\tau\)–neutrino mass has been determined from the decay \(\tau\rightarrow 5\pi^{\pm}\nu_{\tau}\) using data collected with the OPAL detector from 1991 to 1995 in \(\rm e^{+}e^{-}\) collisions at \(\sqrt{s}\approx M_\mathrm{Z}\). A limit of 43.2 MeV at 95% CL is obtained using a two–dimensional method in the \(5\pi\) invariant mass and energy distribution from 22 selected events. Combining this result with OPAL's previously published measurement using \(\rm \tau^{+}\tau^{-}\rightarrow 3h^{\pm}\bar{\nu}_{\tau}+3h^{\mp}\nu_{\tau}\) decays, a new combined limit of \(m_{\nu_{\tau}}

Published
1998

43. Bose-Einstein correlations of three charged pions in hadronic Z $^{\bf 0}$ decays

Author

Erez Etzion, Stefan Kluth, Shlomit Tarem, S. A. Robins, T. Schorner, J. Grunhaus, Tara Shears, R. Liebisch, K. Ackerstaff, Sachio Komamiya, Theodoros Geralis, A. T. Watson, T. P. Kokott, T. Saeki, Alessandra Fanfani, G. Yekutieli, Otmar Biebel, G. G. Hanson, W. R. Gibson, H. M. Fischer, M. Przybycień, M. F. Turner-Watson, Peter R Hobson, J. Goldberg, D. Zer-Zion, M. Fierro, B. Nellen, S. R. Lautenschlager, A. A. Carter, Ron Folman, G. Giacomelli, I. Lawson, M. Boutemeur, F. S. Merritt, H. G. Evans, Gideon Bella, H. J. Burckhart, I. Cohen, Christoph Rembser, A. De Roeck, M. Kobel, O. Runolfsson, M. S. Dixit, Frans Meijers, J. Letts, R. M. Brown, Lorne Levinson, Matthias Schröder, A. W. Lloyd, P. I. Kayal, P. Gagnon, W. M. Sang, Jacqueline Batley, Claudio Grandi, M. Thiergen, J. Bechtluft, J. A. McKenna, Satoshi Mihara, Ekg Sarkisyan, P. E.L. Clarke, S. Yamashita, Kiyotomo Kawagoe, J. P. Martin, Ehud Duchovni, K. Sachs, K. Roscoe, J. von Krogh, M. Hauschild, C. Markopoulos, Norbert Wermes, Sherry Towers, S. De Jong, A. Sittler, Shlomo Dado, T. Kawamoto, Zoltan Laszlo Trocsanyi, P. Vikas, M. Jimack, Claire Shepherd-Themistocleous, P. Igo-Kemenes, P. G. Estabrooks, N. K. Watson, M. Gruwé, Reda Tafirout, Klaus Kurt Desch, A. J. Martin, H. Rick, R. Bartoldus, G. W. Wilson, A. Joly, D. Lanske, S. Orito, L. A. del Pozo, Claudia Ciocca, K. Ishii, H. Jeremie, A. Michelini, E. Torrence, Achim Stahl, E. Clay, H. O. Ogren, S. Betts, M. Hapke, Giora Mikenberg, Satoshi Tanaka, T. Kobayashi, P. M. Watkins, Georges Azuelos, K. Stephens, S. D. Bird, C. Sbarra, F. R. Jacob, E. Tsur, T. J. McMahon, C. Couyoumtzelis, J. Dubbert, R. K. Carnegie, M. Herndon, C. K. Hargrove, K. Nagai, Michael Hildreth, M. Bobinski, J. A. Wilson, S. F. Ashby, K. R. Hossain, N. L. Rodning, J. Böhme, A. D. Schaile, Gabriella Pasztor, C. Hartmann, Christoph Geich-Gimbel, P. S. Wells, Vakhtang Kartvelishvili, P. Vannerem, M. Verzocchi, K. W. Bell, J. Pálinkás, J. C. Hill, O. Schaile, B. Poli, D. Axen, A. Jawahery, Stefan Schmitt, C. Littlewood, A. Biguzzi, D. E. Plane, R. L. Coxe, Silvia Arcelli, M. J. Oreglia, Stephen Hillier, D. Lui, Paul Kyberd, F. K. Loebinger, J. G. Layter, J. E. Conboy, G. M. Dallavalle, A. Fürtjes, James Pinfold, R. Perez-Ochoa, R. Seuster, W. J. McDonald, B. C. Shen, V. Gibson, D. Lazic, G. A. Snow, C. P. Ward, A. Hocker, Terry Richard Wyatt, D. R. Rust, C. R. Jones, J. Steuerer, Ivor Fleck, J. R. Carter, G. N. Patrick, Siegfried Bethke, A. K. Honma, W. G. Scott, Randall Sobie, S. M. Gascon-Shotkin, S. Söldner-Rembold, S. Baumann, S. Robertson, Joleen Pater, D. Chrisman, G. D. Long, Peter Sherwood, G. D. Lafferty, Gregor Herten, T. R. Junk, S. W. O'Neale, I. Nakamura, A. Klier, E. A. Mckigney, Volker Blobel, Alexander Wagner, I. Trigger, K. J. Anderson, Sven Menke, A. M. Rossi, J. Ludwig, Raimund Ströhmer, D. R. Ward, N. Altekamp, H. Voss, K. Runge, T. Kress, P. Bock, D. Glenzinski, Dezso Horvath, M. J. Losty, J. M. Roney, J. Lauber, Stephen Lloyd, J. E. Pilcher, Jean-Arcady Meyer, Dave Charlton, D. I. Futyan, R. J. Barlow, A. M. Lee, D. J. Miller, J. Gascon, P. Poffenberger, D. C. Imrie, John Allison, D. M. Strom, E. von Törne, R. Bürgin, S. D. Talbot, Guenter Duckeck, Paolo Giacomelli, R. Kowalewski, D. Eatough, G. P. Siroli, Shoji Asai, M. Hansroul, Christoph Schwick, Beatrix Dienes, C. Burgard, R. G. Kellogg, M. Fanti, Gideon Alexander, R. J. Homer, Paolo Capiluppi, S. B. Anderson, Daniel Lellouch, R. Mir, C. Y. Chang, R. Hawkings, A. Macpherson, Stefano Marcellini, Richard Keeler, O. C. Cooke, J. W. Gary, Takehiko Mori, P. Taras, P. Pfeifenschneider, Robert McPherson, R. Howard, D. S. Koetke, J. S. White, Mathieu Doucet, J. Patt, André Schöning, P. Mättig, R. D. Heuer, Fabrizio Fabbri, Marcello Mannelli, O. Sahr, Stan Bentvelsen, R. Van Kooten, K. Stoll, V. Zacek, F. Wäckerle, Andris Skuja, D. M. Gingrich, S. Petzold, Tetsuro Mashimo, Richard Teuscher, A. S. Turcot, F. Fiedler, F. G. Oakham, W. Gorn, B. Schmitt, E. L. Barberio, M. Kolrep, I. J. Bloodworth, P. Scharff-Hansen, R. J. Hemingway, B. W. Kennedy, P. Jovanovic, Austin Ball, Yoram Rozen, Peter Krieger, Alessandro Montanari, A. M. Smith, J. Polok, D. Karlen, A. A. Faust, T. Behnke, A. Macchiolo, C. M. Hawkes, Richard Nisius, B. List, Marco Cuffiani, H. Mes, I. P. Duerdoth, S. Braibant, P. Hüntemeyer, R. Davis, P. G. Bright-Thomas, M. Schumacher, E. Lefebvre, F. Odorici, H. A. Neal, F. Scharf, German Martinez, M. A. Thomson, E. K. U. Gross, M. Sproston, J. Schieck, and W. Mohr

Subjects
Physics, Particle physics, Physics and Astronomy (miscellaneous), High Energy Physics::Phenomenology, Nuclear Theory, Hadron, Bose–Einstein correlations, Lambda, Nuclear physics, Near threshold, Pion, Coulomb, High Energy Physics::Experiment, Nuclear Experiment, Coulomb effect, Engineering (miscellaneous)
Abstract

Bose-Einstein Correlations (BEC) of three identical charged pions were studied in $4 \times 10^6$ hadronic ${\rm Z}^0$ decays recorded with the OPAL detector at LEP. The genuine three-pion correlations, corrected for the Coulomb effect, were separated from the known two-pion correlations by a new subtraction procedure. A significant genuine three-pion BEC enhancement near threshold was observed having an emitter source radius of $r_3 = 0.580 \pm 0.004 \mbox{ (stat.)} \pm 0.029 \mbox{ (syst.)} \mbox{ fm}$ and a strength of $\lambda_3 = 0.504 \pm 0.010 \mbox{ (stat.)}\pm 0.041 \mbox{ (syst.)}$ . The Coulomb correction was found to increase the $\lambda_3$ value by $\sim $ 9% and to reduce $r_3$ by $\sim $ 6%. The measured $\lambda_3$ corresponds to a value of $0.707 \pm 0.014 \mbox{ (stat.)} \pm 0.078 \mbox{ (syst.)}$ when one takes into account the three-pion sample purity. A relation between the two-pion and the three-pion source parameters is discussed.

Published
1998

44. An upper limit on the anomalous magnetic moment of the τ lepton

Author

K. Ackerstaff, G. Alexander, J. Allison, N. Altekamp, K.J. Anderson, S. Anderson, S. Arcelli, S. Asai, S.F. Ashby, D. Axen, G. Azuelos, A.H. Ball, E. Barberio, R.J. Barlow, R. Bartoldus, J.R. Batley, S. Baumann, J. Bechtluft, T. Behnke, K.W. Bell, G. Bella, S. Bentvelsen, S. Bethke, S. Betts, O. Biebel, A. Biguzzi, S.D. Bird, V. Blobel, I.J. Bloodworth, M. Bobinski, P. Bock, D. Bonacorsi, M. Boutemeur, S. Braibant, L. Brigliadori, R.M. Brown, H.J. Burckhart, C. Burgard, R. Bürgin, P. Capiluppi, R.K. Carnegie, A.A. Carter, J.R. Carter, C.Y. Chang, D.G. Charlton, D. Chrisman, P.E.L. Clarke, I. Cohen, J.E. Conboy, O.C. Cooke, C. Couyoumtzelis, R.L. Coxe, M. Cuffiani, S. Dado, C. Dallapiccola, G.M. Dallavalle, R. Davis, S. De Jong, L.A. del Pozo, A. de Roeck, K. Desch, B. Dienes, M.S. Dixit, M. Doucet, E. Duchovni, G. Duckeck, I.P. Duerdoth, D. Eatough, P.G. Estabrooks, E. Etzion, H.G. Evans, M. Evans, F. Fabbri, A. Fanfani, M. Fanti, A.A. Faust, L. Feld, F. Fiedler, M. Fierro, H.M. Fischer, I. Fleck, R. Folman, D.G. Fong, M. Foucher, A. Fürtjes, D.I. Futyan, P. Gagnon, J.W. Gary, J. Gascon, S.M. Gascon-Shotkin, N.I. Geddes, C. Geich-Gimbel, T. Geralis, G. Giacomelli, P. Giacomelli, R. Giacomelli, V. Gibson, W.R. Gibson, D.M. Gingrich, D. Glenzinski, J. Goldberg, M.J. Goodrick, W. Gorn, C. Grandi, E. Gross, J. Grunhaus, M. Gruwé, C. Hajdu, G.G. Hanson, M. Hansroul, M. Hapke, C.K. Hargrove, P.A. Hart, C. Hartmann, M. Hauschild, C.M. Hawkes, R. Hawkings, R.J. Hemingway, M. Herndon, G. Herten, R.D. Heuer, M.D. Hildreth, J.C. Hill, S.J. Hillier, P.R. Hobson, A. Hocker, R.J. Homer, A.K. Honma, D. Horváth, K.R. Hossain, R. Howard, P. Hüntemeyer, D.E. Hutchcroft, P. Igo-Kemenes, D.C. Imrie, K. Ishii, A. Jawahery, P.W. Jeffreys, H. Jeremie, M. Jimack, A. Joly, C.R. Jones, M. Jones, U. Jost, P. Jovanovic, T.R. Junk, J. Kanzaki, D. Karlen, V. Kartvelishvili, K. Kawagoe, T. Kawamoto, P.I. Kayal, R.K. Keeler, R.G. Kellogg, B.W. Kennedy, J. Kirk, A. Klier, S. Kluth, T. Kobayashi, M. Kobel, D.S. Koetke, T.P. Kokott, M. Kolrep, S. Komamiya, R.V. Kowalewski, T. Kress, P. Krieger, J. von Krogh, P. Kyberd, G.D. Lafferty, R. Lahmann, W.P. Lai, D. Lanske, J. Lauber, S.R. Lautenschlager, I. Lawson, J.G. Layter, D. Lazic, A.M. Lee, E. Lefebvre, D. Lellouch, J. Letts, L. Levinson, B. List, S.L. Lloyd, F.K. Loebinger, G.D. Long, M.J. Losty, J. Ludwig, D. Lui, A. Macchiolo, A. Macpherson, M. Mannelli, S. Marcellini, C. Markopoulos, C. Markus, A.J. Martin, J.P. Martin, G. Martinez, T. Mashimo, P. Mättig, W.J. McDonald, J. McKenna, E.A. Mckigney, T.J. McMahon, R.A. McPherson, F. Meijers, S. Menke, F.S. Merritt, H. Mes, J. Meyer, A. Michelini, S. Mihara, G. Mikenberg, D.J. Miller, A. Mincer, R. Mir, W. Mohr, A. Montanari, T. Mori, K. Nagai, I. Nakamura, H.A. Neal, B. Nellen, R. Nisius, S.W. O'Neale, F.G. Oakham, F. Odorici, H.O. Ogren, A. Oh, N.J. Oldershaw, M.J. Oreglia, S. Orito, J. Pálinkás, G. Pásztor, J.R. Pater, G.N. Patrick, J. Patt, R. Perez-Ochoa, S. Petzold, P. Pfeifenschneider, J.E. Pilcher, J. Pinfold, D.E. Plane, P. Poffenberger, B. Poli, A. Posthaus, C. Rembser, S. Robertson, S.A. Robins, N. Rodning, J.M. Roney, A. Rooke, A.M. Rossi, P. Routenburg, Y. Rozen, K. Runge, O. Runolfsson, U. Ruppel, D.R. Rust, K. Sachs, T. Saeki, O. Sahr, W.M. Sang, E.K.G. Sarkisyan, C. Sbarra, A.D. Schaile, O. Schaile, F. Scharf, P. Scharff-Hansen, J. Schieck, P. Schleper, B. Schmitt, S. Schmitt, A. Schöning, M. Schröder, M. Schumacher, C. Schwick, W.G. Scott, T.G. Shears, B.C. Shen, C.H. Shepherd-Themistocleous, P. Sherwood, R.P.B. Sieberg, G.P. Siroli, A. Sittler, A. Skillman, A. Skuja, A.M. Smith, G.A. Snow, R. Sobie, S. Söldner-Rembold, R.W. Springer, M. Sproston, K. Stephens, J. Steuerer, B. Stockhausen, K. Stoll, D. Strom, R. Ströhmer, P. Szymanski, R. Tafirout, S.D. Talbot, P. Taras, S. Tarem, R. Teuscher, M. Thiergen, M.A. Thomson, E. von Törne, E. Torrence, S. Towers, I. Trigger, Z. Trócsányi, E. Tsur, A.S. Turcot, M.F. Turner-Watson, I. Ueda, P. Utzat, R. Van Kooten, P. Vannerem, M. Verzocchi, P. Vikas, E.H. Vokurka, H. Voss, F. Wäckerle, A. Wagner, C.P. Ward, D.R. Ward, P.M. Watkins, A.T. Watson, N.K. Watson, P.S. Wells, N. Wermes, J.S. White, G.W. Wilson, J.A. Wilson, T.R. Wyatt, S. Yamashita, G. Yekutieli, V. Zacek, and D. Zer-Zion

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Anomalous magnetic dipole moment, 010308 nuclear & particles physics, Form factor (quantum field theory), 01 natural sciences, High Energy Physics - Experiment, Dipole, 0103 physical sciences, Magnetic form factor, Radiative transfer, Vertex (curve), High Energy Physics::Experiment, Production (computer science), 010306 general physics, Particle Physics - Experiment, Lepton
Abstract

Using radiative Z^0 -> \tau^+ \tau^- \gamma events collected with the OPAL detector at LEP at \sqrt{s}= M_Z during 1990-95, a direct study of the electromagnetic current at the \tau\gamma vertex has been performed in terms of the anomalous magnetic form factor F_2 of the \tau lepton. The analysis is based on a data sample of 1429 e^+ e^- -> \tau^+ \tau^- \gamma events which are examined for a deviation from the expectation with F_2 = 0. From the non-observation of anomalous \tau^+ \tau^- \gamma production a limit of -0.068 < F_2 < 0.065 is obtained. This can also be interpreted as a limit on the electric dipole form factor F_3 as -3.8 x 10^-16 e-cm < eF_3 < 3.6 x 10^-16 e-cm. The above ranges are valid at the 95% confidence level., Comment: 20 pages, LaTeX, uses a4p.sty, 4 eps figures included, submitted to Phys. Lett. B

Published
1998

45. Search for an excess in the production of four-jet events from e+e− collisions at =130–184 GeV

Author

K. Ackerstaff, G. Alexander, J. Allison, N. Altekamp, K.J. Anderson, S. Anderson, S. Arcelli, S. Asai, S.F. Ashby, D. Axen, G. Azuelos, A.H. Ball, E. Barberio, R.J. Barlow, R. Bartoldus, J.R. Batley, S. Baumann, J. Bechtluft, T. Behnke, K.W. Bell, G. Bella, S. Bentvelsen, S. Bethke, S. Betts, O. Biebel, A. Biguzzi, S.D. Bird, V. Blobel, I.J. Bloodworth, M. Bobinski, P. Bock, D. Bonacorsi, M. Boutemeur, S. Braibant, L. Brigliadori, R.M. Brown, H.J. Burckhart, C. Burgard, R. Bürgin, P. Capiluppi, R.K. Carnegie, A.A. Carter, J.R. Carter, C.Y. Chang, D.G. Charlton, D. Chrisman, P.E.L. Clarke, I. Cohen, J.E. Conboy, O.C. Cooke, C. Couyoumtzelis, R.L. Coxe, M. Cuffiani, S. Dado, C. Dallapiccola, G.M. Dallavalle, R. Davis, S. De Jong, L.A. del Pozo, A. de Roeck, K. Desch, B. Dienes, M.S. Dixit, M. Doucet, E. Duchovni, G. Duckeck, I.P. Duerdoth, D. Eatough, P.G. Estabrooks, E. Etzion, H.G. Evans, M. Evans, F. Fabbri, A. Fanfani, M. Fanti, A.A. Faust, L. Feld, F. Fiedler, M. Fierro, H.M. Fischer, I. Fleck, R. Folman, D.G. Fong, M. Foucher, A. Fürtjes, D.I. Futyan, P. Gagnon, J.W. Gary, J. Gascon, S.M. Gascon-Shotkin, N.I. Geddes, C. Geich-Gimbel, T. Geralis, G. Giacomelli, P. Giacomelli, R. Giacomelli, V. Gibson, W.R. Gibson, D.M. Gingrich, D. Glenzinski, J. Goldberg, M.J. Goodrick, W. Gorn, C. Grandi, E. Gross, J. Grunhaus, M. Gruwé, C. Hajdu, G.G. Hanson, M. Hansroul, M. Hapke, C.K. Hargrove, P.A. Hart, C. Hartmann, M. Hauschild, C.M. Hawkes, R. Hawkings, R.J. Hemingway, M. Herndon, G. Herten, R.D. Heuer, M.D. Hildreth, J.C. Hill, S.J. Hillier, P.R. Hobson, A. Hocker, R.J. Homer, A.K. Honma, D. Horváth, K.R. Hossain, R. Howard, P. Hüntemeyer, D.E. Hutchcroft, P. Igo-Kemenes, D.C. Imrie, K. Ishii, A. Jawahery, P.W. Jeffreys, H. Jeremie, M. Jimack, A. Joly, C.R. Jones, M. Jones, U. Jost, P. Jovanovic, T.R. Junk, J. Kanzaki, D. Karlen, V. Kartvelishvili, K. Kawagoe, T. Kawamoto, P.I. Kayal, R.K. Keeler, R.G. Kellogg, B.W. Kennedy, J. Kirk, A. Klier, S. Kluth, T. Kobayashi, M. Kobel, D.S. Koetke, T.P. Kokott, M. Kolrep, S. Komamiya, R.V. Kowalewski, T. Kress, P. Krieger, J. von Krogh, P. Kyberd, G.D. Lafferty, R. Lahmann, W.P. Lai, D. Lanske, J. Lauber, S.R. Lautenschlager, I. Lawson, J.G. Layter, D. Lazic, A.M. Lee, E. Lefebvre, D. Lellouch, J. Letts, L. Levinson, B. List, S.L. Lloyd, F.K. Loebinger, G.D. Long, M.J. Losty, J. Ludwig, D. Lui, A. Macchiolo, A. Macpherson, M. Mannelli, S. Marcellini, C. Markopoulos, C. Markus, A.J. Martin, J.P. Martin, G. Martinez, T. Mashimo, P. Mättig, W.J. McDonald, J. McKenna, E.A. Mckigney, T.J. McMahon, R.A. McPherson, F. Meijers, S. Menke, F.S. Merritt, H. Mes, J. Meyer, A. Michelini, S. Mihara, G. Mikenberg, D.J. Miller, A. Mincer, R. Mir, W. Mohr, A. Montanari, T. Mori, K. Nagai, I. Nakamura, H.A. Neal, B. Nellen, R. Nisius, S.W. O'Neale, F.G. Oakham, F. Odorici, H.O. Ogren, A. Oh, N.J. Oldershaw, M.J. Oreglia, S. Orito, J. Pálinkás, G. Pásztor, J.R. Pater, G.N. Patrick, J. Patt, R. Perez-Ochoa, S. Petzold, P. Pfeifenschneider, J.E. Pilcher, J. Pinfold, D.E. Plane, P. Poffenberger, B. Poli, A. Posthaus, C. Rembser, S. Robertson, S.A. Robins, N. Rodning, J.M. Roney, A. Rooke, A.M. Rossi, P. Routenburg, Y. Rozen, K. Runge, O. Runolfsson, U. Ruppel, D.R. Rust, K. Sachs, T. Saeki, O. Sahr, W.M. Sang, E.K.G. Sarkisyan, C. Sbarra, A.D. Schaile, O. Schaile, F. Scharf, P. Scharff-Hansen, J. Schieck, P. Schleper, B. Schmitt, S. Schmitt, A. Schöning, M. Schröder, M. Schumacher, C. Schwick, W.G. Scott, T.G. Shears, B.C. Shen, C.H. Shepherd-Themistocleous, P. Sherwood, G.P. Siroli, A. Sittler, A. Skillman, A. Skuja, A.M. Smith, G.A. Snow, R. Sobie, S. Söldner-Rembold, R.W. Springer, M. Sproston, K. Stephens, J. Steuerer, B. Stockhausen, K. Stoll, D. Strom, R. Ströhmer, P. Szymanski, R. Tafirout, S.D. Talbot, P. Taras, S. Tarem, R. Teuscher, M. Thiergen, M.A. Thomson, E. von Törne, E. Torrence, S. Towers, I. Trigger, Z. Trócsányi, E. Tsur, A.S. Turcot, M.F. Turner-Watson, I. Ueda, P. Utzat, R. Van Kooten, P. Vannerem, M. Verzocchi, P. Vikas, E.H. Vokurka, H. Voss, F. Wäckerle, A. Wagner, C.P. Ward, D.R. Ward, P.M. Watkins, A.T. Watson, N.K. Watson, P.S. Wells, N. Wermes, J.S. White, G.W. Wilson, J.A. Wilson, T.R. Wyatt, S. Yamashita, G. Yekutieli, V. Zacek, and D. Zer-Zion

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Aleph, 010308 nuclear & particles physics, FOS: Physical sciences, Jet (particle physics), 01 natural sciences, High Energy Physics - Experiment, Standard Model, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, High Energy Physics::Experiment, Production (computer science), 010306 general physics, Particle Physics - Experiment
Abstract

Events with four distinct jets from e^+e^- collisions, collected by the OPAL detector at centre-of-mass energies between 130 and 184 GeV, are analysed for a peak in the sum of dijet masses. This search is motivated by the ALEPH Collaboration's observation of a clear excess of events with dijet mass sums close to 105 GeV in data taken at centre-of-mass energies of 130 and 136 GeV in 1995. We have observed no significant excess of four-jet events compared to the Standard Model expectation for any dijet mass sum at any energy. Our observation is inconsistent with the excess observed by ALEPH in 1995. Upper limits are determined on the production cross-section as a function of the dijet mass sum., Comment: 24 pages, LaTeX, uses a4p.sty, 5 eps figures included, submitted to Physics Letters B

Published
1998

46. Production of ${\rm f_0}(980)$ , ${\rm f}_2(1270)$ and $\phi(1020)$ in hadronic ${\rm Z}^0$ decay

Author

S. Betts, S. Yamashita, M. Hapke, J. Letts, P. Igo-Kemenes, D. E. Hutchcroft, K. Ishii, H. Jeremie, K. Sachs, A. Biguzzi, A. Rooke, J. G. Layter, Paolo Giacomelli, P. S. Wells, M. J. Oreglia, Shlomo Dado, O. Schaile, M. Hansroul, S. R. Lautenschlager, Terry Richard Wyatt, R. Lahmann, D. C. Imrie, L. Brigliadori, Sven Menke, Gideon Bella, T. Behnke, J. R. Carter, C. Burgard, G. N. Patrick, Stefan Schmitt, C. Hartmann, D. E. Plane, Stephen Hillier, G. M. Dallavalle, H. J. Burckhart, Jacqueline Batley, H. M. Fischer, R. J. Hemingway, Giora Mikenberg, S. F. Ashby, R. W. Springer, A. Macpherson, G. P. Siroli, Otmar Biebel, R. J. Homer, B. W. Kennedy, Christoph Schwick, A. Macchiolo, Tara Shears, P. Jovanovic, C. R. Jones, W. M. Sang, Austin Ball, O. Runolfsson, N. J. Oldershaw, J. Lauber, C. M. Hawkes, Peter Krieger, P. A. Hart, Kiyotomo Kawagoe, S. W. O'Neale, Georges Azuelos, Shoji Asai, G. G. Hanson, G. Yekutieli, E. Tsur, M. Boutemeur, F. S. Merritt, K. J. Anderson, M. Verzocchi, Richard Nisius, Alessandro Montanari, Richard Teuscher, A. D. Schaile, K. W. Bell, P. I. Kayal, J. Pálinkás, Gabriella Pasztor, H. A. Neal, R. Howard, M. F. Turner-Watson, J. S. White, A. S. Turcot, F. Fiedler, G. Giacomelli, J. C. Hill, B. List, I. Lawson, Daniel Lellouch, C. Y. Chang, W. J. McDonald, Dave Charlton, A. De Roeck, P. Vannerem, U. Ruppel, A. A. Carter, Marco Cuffiani, Norbert Wermes, B. C. Shen, Peter R Hobson, H. Mes, Ron Folman, P. Taras, G. W. Wilson, D. Zer-Zion, D. Lui, K. R. Hossain, R. Bürgin, Michael Kobel, Siegfried Bethke, A. K. Honma, M. Hauschild, C. Markopoulos, U. Jost, R. Mir, R. Hawkings, M. S. Dixit, I. P. Duerdoth, W. G. Scott, Sherry Towers, I. Nakamura, C. Markus, Frans Meijers, T. Kawamoto, Claudio Grandi, S. Braibant, P. Utzat, P. Routenburg, Matthias Schröder, E. H. Vokurka, P. E.L. Clarke, J. Grunhaus, Allen Mincer, M. K. Jones, Erez Etzion, Stefan Kluth, Shlomit Tarem, Takehiko Mori, P. Mättig, J. P. Martin, G. A. Snow, C. P. Ward, A. Joly, V. Zacek, D. Glenzinski, Dezso Horvath, M. J. Losty, S. Robertson, Julie Kirk, M. Thiergen, Gregor Herten, Jean-Arcady Meyer, Ikuo Ueda, D. M. Strom, S. Orito, J. Bechtluft, Raimund Ströhmer, Daniele Bonacorsi, R. L. Coxe, S. De Jong, P. G. Estabrooks, R. K. Keeler, N. K. Watson, P. M. Watkins, S. D. Talbot, F. G. Oakham, B. Schmitt, O. C. Cooke, Claire Shepherd-Themistocleous, P. Pfeifenschneider, M. Kolrep, E. L. Barberio, J. A. McKenna, J. E. Pilcher, S. Söldner-Rembold, P. Hüntemeyer, C. Sbarra, D. Eatough, Sachio Komamiya, C. Dallapiccola, P. Poffenberger, Theodoros Geralis, A. T. Watson, Randall Sobie, G. D. Lafferty, J. Patt, André Schöning, J. von Krogh, A. A. Faust, S. A. Robins, O. Sahr, N. Altekamp, H. Voss, T. P. Kokott, M. Gruwé, R. J. Barlow, T. Saeki, D. J. Miller, R. Bartoldus, A. J. Martin, R. Davis, L. A. del Pozo, B. Stockhausen, Paul Kyberd, F. K. Loebinger, Alessandra Fanfani, K. Ackerstaff, P. Scharff-Hansen, T. J. McMahon, Beatrix Dienes, I. J. Bloodworth, A. Hocker, H. O. Ogren, J. Steuerer, C. Couyoumtzelis, Ivor Fleck, Silvia Arcelli, M. Schumacher, E. Lefebvre, S. M. Gascon-Shotkin, R. K. Carnegie, Guenter Duckeck, Satoshi Mihara, Joleen Pater, M. Herndon, Christoph Geich-Gimbel, A. Klier, M. Bobinski, J. A. Wilson, C. K. Hargrove, R. Giacomelli, A. Oh, F. Odorici, M. Fierro, P. Gagnon, S. Baumann, Ekg Sarkisyan, Yoram Rozen, S. B. Anderson, M. Foucher, D. Chrisman, G. D. Long, D. Lazic, Matthew Evans, A. M. Rossi, John Allison, P. Szymanski, E. A. Mckigney, P. W. Jeffreys, W. P. Lai, Vakhtang Kartvelishvili, K. Stephens, Junichi Kanzaki, R. G. Kellogg, J. E. Conboy, A. Fürtjes, Csaba Hajdu, D. Karlen, A. Sittler, Stefano Marcellini, J. Goldberg, J. M. Roney, Stan Bentvelsen, Lutz Feld, N. I. Geddes, Peter Schleper, Michael Hildreth, V. Gibson, N. L. Rodning, Zoltan Laszlo Trocsanyi, B. Poli, D. I. Futyan, B. Nellen, Volker Blobel, T. R. Junk, P. Vikas, D. Lanske, I. Trigger, D. R. Ward, T. Kress, A. M. Smith, S. D. Bird, D. Axen, A. Jawahery, H. G. Evans, Peter Sherwood, M. J. Goodrick, I. Cohen, Christoph Rembser, Alexander Wagner, J. Ludwig, K. Runge, P. Bock, Stephen Lloyd, James Pinfold, R. Perez-Ochoa, D. G. Fong, J. Gascon, Ehud Duchovni, M. Jimack, J. W. Gary, D. S. Koetke, A. Michelini, Marcello Mannelli, K. Stoll, Andris Skuja, T. Kobayashi, S. Petzold, Tetsuro Mashimo, W. Gorn, R. Kowalewski, R. Van Kooten, Gideon Alexander, Paolo Capiluppi, F. Wäckerle, D. M. Gingrich, M. Fanti, W. R. Gibson, Robert McPherson, Mathieu Doucet, R. M. Brown, Lorne Levinson, A. Skillman, R. D. Heuer, Reda Tafirout, Klaus Kurt Desch, Fabrizio Fabbri, E. Torrence, K. Nagai, D. R. Rust, A. M. Lee, E. von Törne, F. Scharf, German Martinez, M. A. Thomson, E. K. U. Gross, M. Sproston, J. Schieck, W. Mohr, and A. Posthaus

Subjects
Physics, Particle physics, Physics and Astronomy (miscellaneous), Meson, Hadron, Fragmentation function, High Energy Physics::Experiment, Channel analysis, Scalar meson, Engineering (miscellaneous)
Abstract

Inclusive production of the \({\rm f_0}(980)\), \({\rm f}_2(1270)\) and \(\phi(1020)\) resonances has been studied in a sample of 4.3 million hadronic \({\rm Z}^0\) decays from the OPAL experiment at LEP. A coupled channel analysis has been used for the \({\rm f}_0\) in simultaneous fits to the resonances in inclusive \(\pi^+\pi^-\) and \({\rm K^+K^-}\) mass spectra. Fragmentation functions are reported for the three states. Total inclusive rates are measured to be \(0.141 \pm 0.007 \pm 0.011\)\({\rm f}_0\), \(0.155\pm0.011\pm0.018\)\({\rm f}_2\) and \(0.091\pm0.002\pm0.003\)\(\phi\) mesons per hadronic \({\rm Z}^0\) decay. The production properties of the \({\rm f}_0\), including those in three-jet events, are compared with those of the \({\rm f}_2\) and \(\phi\), and with the Lund string model of hadron production. All measurements are consistent with the hypothesis that the \({\rm f_0}(980)\) is a conventional \({\rm q\bar q}\) scalar meson.

Published
1998

47. Search for anomalous production of photonic events with missing energy in ${\rm e^+e^-}$ collisions at $\sqrt{s} = 130$ –172 GeV

Author

A. Klier, P. Routenburg, C. Dallapiccola, M. Hauschild, C. Markopoulos, C. Markus, G. T. Jones, E. H. Vokurka, N. Altekamp, H. Voss, S. Orito, W. Gorn, S. R. Lautenschlager, H. A. Neal, R. J. Barlow, D. J. Miller, Stefan Kluth, E. K.G. Sarkisyan, U. Ruppel, M. R. Ingram, J. Lauber, S. Betts, M. Hapke, W. J. McDonald, A. Sittler, P. G. Estabrooks, O. Runolfsson, G. W. Wilson, V. Zacek, D. E. Hutchcroft, N. J. Oldershaw, Gideon Bella, R. Howard, U. Jost, N. K. Watson, S. D. Talbot, G. Yekutieli, P. Scharff-Hansen, A. D. Schaile, H. J. Burckhart, Jacqueline Batley, C. Beeston, M. J. Oreglia, W. M. Sang, Gregor Herten, B. Wilkens, A. Biguzzi, Raimund Ströhmer, N. Rodning, P. M. Watkins, A. Rooke, J. E. Pilcher, Gabriella Pasztor, Claudio Grandi, J. Grunhaus, D. C. Imrie, P. R. Hobson, J. G. Layter, I. Nakamura, A. K. Honma, R. Van Kooten, F. G. Oakham, D. Eatough, B. Schmitt, E. L. Barberio, R. Bartoldus, D. Lui, B. Nellen, A. M. Smith, A. Oh, Paolo Capiluppi, J-P. Meyer, John Allison, Richard Keeler, R. J. Hemingway, H. O. Ogren, L. Levinson, G. D. Long, M. Schumacher, K. Stephens, G. A. Snow, C. P. Ward, E. Lefebvre, R. L. Coxe, Christoph Geich-Gimbel, J. R. Carter, Georges Azuelos, C. R. Jones, G. Mikenberg, T. Kawamoto, Stefan Schmitt, A. Macpherson, B. W. Kennedy, P. Jovanovic, R. Lahmann, Austin Ball, S. Söldner-Rembold, F. Odorici, A. Hocker, G. N. Patrick, Peter Krieger, R. G. Kellogg, P. E.L. Clarke, Alessandro Montanari, R. Davis, Silvia Arcelli, Hans-Christian Schultz-Coulon, Csaba Hajdu, D. Chrisman, R. Perez-Ochoa, G. D. Lafferty, M. Verzocchi, K. W. Bell, Otmar Biebel, H. G. Evans, M. J. Goodrick, P. Igo-Kemenes, N. I. Geddes, Michael Hildreth, P. Gagnon, M. K. Jones, J. P. Martin, J. Letts, Christoph Rembser, E. Tsur, S. Komamiya, V. Gibson, J. S. White, Stefano Marcellini, C. Hartmann, D. G. Fong, J. Gascon, D. E. Plane, S. Dado, J. Pinfold, J. C. Hill, D. Lazic, T. J. McMahon, C. Couyoumtzelis, P. Mättig, S. Asai, Vakhtang Kartvelishvili, G. P. Siroli, S. De Jong, Christoph Schwick, K. Ackerstaff, F. Fiedler, F. Wäckerle, L. Brigliadori, S. Baumann, H. Jeremie, Stephen Lloyd, Stephen Hillier, R. K. Carnegie, E. Gross, Dave Charlton, B. Poli, F. Scharf, German Martinez, I. J. Bloodworth, Peter Schleper, K. Kawagoe, J. E. Conboy, A. Fürtjes, K. Sachs, J. Goldberg, E. A. Mckigney, S. Tarem, B. C. Shen, G. M. Dallavalle, T. R. Junk, J. M. Roney, M. Fierro, J. E.G. Edwards, R. Bürgin, H. M. Fischer, A. N. Bell, D. M. Gingrich, M. Herndon, B. Dienes, I. Trigger, A. Joly, J. W. Gary, W. P. Lai, D. S. Koetke, Marcello Mannelli, Guenter Duckeck, Lutz Feld, R. Mir, M. Bobinski, Norbert Wermes, Sherry Towers, Paolo Giacomelli, J. A. Wilson, M. Hansroul, D. R. Ward, M. Jimack, Siegfried Bethke, T. Kress, W. G. Scott, A. Michelini, H. Mes, O. Schaile, P. W. Jeffreys, M. Foucher, I. P. Duerdoth, S. D. Bird, G. G. Hanson, A. M. Lee, G. Alexander, M. Boutemeur, F. S. Merritt, Richard Teuscher, S. Braibant, S. Yamashita, R. Rylko, B. Stockhausen, Paul Kyberd, F. K. Loebinger, D. I. Futyan, A. S. Turcot, C. Burgard, I. Cohen, Ivor Fleck, G. Giacomelli, S. W. O'Neale, A. Jawahery, Joleen Pater, M. F. Turner-Watson, R. W. Springer, R. J. Homer, D. Karlen, T. Saeki, P. I. Kayal, S. F. Ashby, R. Giacomelli, Sven Menke, Daniele Bonacorsi, Z. Trácsanyi, Peter Sherwood, S. Mihara, S. M. Gascon-Shotkin, M. A. Thomson, S. Robertson, D. Glenzinski, Dezso Horvath, M. J. Losty, R. Sobie, M. S. Dixit, Frans Meijers, P. S. Wells, J. Bechtluft, K. J. Anderson, M. Fanti, D. Zer-Zion, V. Blobel, J. A. McKenna, J. Ludwig, Reda Tafirout, Klaus Kurt Desch, S. A. Robins, R. Hawkings, K. Runge, P. Bock, E. Torrence, S. Petzold, Matthew Evans, A. M. Rossi, M. Kolrep, M. Sproston, Terry Richard Wyatt, C. Y. Chang, P. Vikas, D. Lanske, T. Mori, J. von Krogh, D. Lellouch, W. R. Gibson, J. E. Bloomer, D. Axen, K. R. Hossain, S. B. Anderson, J. Pálinkás, J. Kirk, P. Szymanski, P. Taras, Michael Kobel, R. M. Brown, E. von Tärne, Theodoros Geralis, A. Skillman, O. C. Cooke, P. Pfeifenschneider, A. T. Watson, L. A. del Pozo, Stan Bentvelsen, Allen Mincer, T. P. Kokott, T. Mashimo, Alessandra Fanfani, J. Patt, André Schöning, Robert McPherson, C. Sbarra, P. Huntemeyer, A. A. Carter, Ron Folman, T. Kobayashi, Mathieu Doucet, R. D. Heuer, P. Utzat, A. A. Faust, Fabrizio Fabbri, J. Schieck, D. M. Strom, E. Duchovni, W. Mohr, A. Posthaus, K. Nagai, D. R. Rust, J. Kanzaki, S. Tanaka, Tara Shears, P. A. Hart, P. Poffenberger, K. Ishii, Claire Shepherd-Themistocleous, A. Wagner, Matthias Schröder, T. Behnke, J. Steuerer, M. Thiergen, A. Macchiolo, M. Gruwé, C. M. Hawkes, Richard Nisius, Marco Cuffiani, U. Müller, A. J. Martin, C. K. Hargrove, K. Stoll, Andris Skuja, and Y. Rozen

Subjects
Physics, Particle physics, Missing energy, Physics and Astronomy (miscellaneous), Electron–positron annihilation, Physics beyond the Standard Model, Standard Model, Nuclear physics, Pair production, Neutralino, High Energy Physics::Experiment, Production (computer science), Engineering (miscellaneous), Energy (signal processing)
Abstract

Photonic events with large missing energy have been observed in \(\mathrm{e^+e^-}\) collisions at centre-of-mass energies of 130, 136, 161 and 172 GeV using the OPAL detector at LEP. Results are presented based on search topologies designed to select events with a single photon and missing transverse energy or events with a pair of acoplanar photons. In both search topologies, cross-section measurements are performed within the kinematic acceptance of the selection. These results are compared with the expectations from the Standard Model processes \({\rm e^+e^-}\to \nu\overline\nu \gamma (\gamma )\) (single-photon) and \({\rm e^+e^-}\to \nu\overline\nu \gamma \gamma (\gamma )\) (acoplanar-photons). No evidence is observed for new physics contributions to these final states. Upper limits on \(\sigma({\rm e^+e^- \to XY)\cdot BR(X\to Y\gamma })\) and \(\sigma({\rm e^+e^- \to XX)\cdot BR^2(X\to Y\gamma })\) are derived for the case of stable and invisible Y. These limits apply to single and pair production of excited neutrinos (\({\rm X}= \nu^*,{\rm Y}= \nu\)), to neutralino production (\({\rm X}=\tilde\chi^0_2, {\rm Y}=\tilde\chi^0_1\)), and to supersymmetric models in which \({\rm X}= \tilde\chi^0_1\) and \({\rm Y}=\tilde{\rm G}\) is a light gravitino. For the latter scenario, the results of the acoplanar-photons search are used to provide mode l-dependent lower limits on the mass of the lightest neutralino.

Published
1998

48. Measurements of the Bs0 and Λb0 lifetimes

Author

K Ackerstaff, G Alexander, J Allison, N Altekamp, K.J Anderson, S Anderson, S Arcelli, S Asai, S.F Ashby, D Axen, G Azuelos, A.H Ball, E Barberio, R.J Barlow, R Bartoldus, J.R Batley, S Baumann, J Bechtluft, C Beeston, T Behnke, A.N Bell, K.W Bell, G Bella, S Bentvelsen, S Bethke, S Betts, O Biebel, A Biguzzi, S.D Bird, V Blobel, I.J Bloodworth, J.E Bloomer, M Bobinski, P Bock, D Bonacorsi, M Boutemeur, S Braibant, L Brigliadori, R.M Brown, H.J Burckhart, C Burgard, R Bürgin, P Capiluppi, R.K Carnegie, A.A Carter, J.R Carter, C.Y Chang, D.G Charlton, D Chrisman, P.E.L Clarke, I Cohen, J.E Conboy, O.C Cooke, C Couyoumtzelis, R.L Coxe, M Cuffiani, S Dado, C Dallapiccola, G.M Dallavalle, R Davis, S De Jong, L.A del Pozo, K Desch, B Dienes, M.S Dixit, M Doucet, E Duchovni, G Duckeck, I.P Duerdoth, D Eatough, J.E.G Edwards, P.G Estabrooks, H.G Evans, M Evans, F Fabbri, A Fanfani, M Fanti, A.A Faust, L Feld, F Fiedler, M Fierro, H.M Fischer, I Fleck, R Folman, D.G Fong, M Foucher, A Fürtjes, D.I Futyan, P Gagnon, J.W Gary, J Gascon, S.M Gascon-Shotkin, N.I Geddes, C Geich-Gimbel, T Geralis, G Giacomelli, P Giacomelli, R Giacomelli, V Gibson, W.R Gibson, D.M Gingrich, D Glenzinski, J Goldberg, M.J Goodrick, W Gorn, C Grandi, E Gross, J Grunhaus, M Gruwé, C Hajdu, G.G Hanson, M Hansroul, M Hapke, C.K Hargrove, P.A Hart, C Hartmann, M Hauschild, C.M Hawkes, R Hawkings, R.J Hemingway, M Herndon, G Herten, R.D Heuer, M.D Hildreth, J.C Hill, S.J Hillier, P.R Hobson, A Hocker, R.J Homer, A.K Honma, D Horváth, K.R Hossain, R Howard, P Hüntemeyer, D.E Hutchcroft, P Igo-Kemenes, D.C Imrie, M.R Ingram, K Ishii, A Jawahery, P.W Jeffreys, H Jeremie, M Jimack, A Joly, C.R Jones, G Jones, M Jones, U Jost, P Jovanovic, T.R Junk, J Kanzaki, D Karlen, V Kartvelishvili, K Kawagoe, T Kawamoto, P.I Kayal, R.K Keeler, R.G Kellogg, B.W Kennedy, J Kirk, A Klier, S Kluth, T Kobayashi, M Kobel, D.S Koetke, T.P Kokott, M Kolrep, S Komamiya, T Kress, P Krieger, J von Krogh, P Kyberd, G.D Lafferty, R Lahmann, W.P Lai, D Lanske, J Lauber, S.R Lautenschlager, J.G Layter, D Lazic, A.M Lee, E Lefebvre, D Lellouch, J Letts, L Levinson, S.L Lloyd, F.K Loebinger, G.D Long, M.J Losty, J Ludwig, D Lui, A Macchiolo, A Macpherson, M Mannelli, S Marcellini, C Markopoulos, C Markus, A.J Martin, J.P Martin, G Martinez, T Mashimo, P Mättig, W.J McDonald, J McKenna, E.A Mckigney, T.J McMahon, R.A McPherson, F Meijers, S Menke, F.S Merritt, H Mes, J Meyer, A Michelini, G Mikenberg, D.J Miller, A Mincer, R Mir, W Mohr, A Montanari, T Mori, U Müller, S Mihara, K Nagai, I Nakamura, H.A Neal, B Nellen, R Nisius, S.W O'Neale, F.G Oakham, F Odorici, H.O Ogren, A Oh, N.J Oldershaw, M.J Oreglia, S Orito, J Pálinkás, G Pásztor, J.R Pater, G.N Patrick, J Patt, R Perez-Ochoa, S Petzold, P Pfeifenschneider, J.E Pilcher, J Pinfold, D.E Plane, P Poffenberger, B Poli, A Posthaus, C Rembser, S Robertson, S.A Robins, N Rodning, J.M Roney, A Rooke, A.M Rossi, P Routenburg, Y Rozen, K Runge, O Runolfsson, U Ruppel, D.R Rust, R Rylko, K Sachs, T Saeki, W.M Sang, E.K.G Sarkisyan, C Sbarra, A.D Schaile, O Schaile, F Scharf, P Scharff-Hansen, J Schieck, P Schleper, B Schmitt, S Schmitt, A Schöning, M Schröder, H.C Schultz-Coulon, M Schumacher, C Schwick, W.G Scott, T.G Shears, B.C Shen, C.H Shepherd-Themistocleous, P Sherwood, G.P Siroli, A Sittler, A Skillman, A Skuja, A.M Smith, G.A Snow, R Sobie, S Söldner-Rembold, R.W Springer, M Sproston, K Stephens, J Steuerer, B Stockhausen, K Stoll, D Strom, R Ströhmer, P Szymanski, R Tafirout, S.D Talbot, S Tanaka, P Taras, S Tarem, R Teuscher, M Thiergen, M.A Thomson, E von Törne, E Torrence, S Towers, I Trigger, Z Trócsányi, E Tsur, A.S Turcot, M.F Turner-Watson, P Utzat, R Van Kooten, M Verzocchi, P Vikas, E.H Vokurka, H Voss, F Wäckerle, A Wagner, C.P Ward, D.R Ward, P.M Watkins, A.T Watson, N.K Watson, P.S Wells, N Wermes, J.S White, B Wilkens, G.W Wilson, J.A Wilson, T.R Wyatt, S Yamashita, G Yekutieli, V Zacek, and D Zer-Zion

Subjects
Baryon, Physics, Nuclear and High Energy Physics, Particle physics, Meson, 010308 nuclear & particles physics, 0103 physical sciences, Hadron, High Energy Physics::Experiment, 010306 general physics, Lambda, 01 natural sciences, Bar (unit)
Abstract

This paper presents updated measurements of the lifetimes of the B^0_s meson and the \Lambda_b baryon using 4.4 million hadronic Z^0 decays recorded by the OPAL detector at LEP from 1990 to 1995. A sample of B^0_s decays is obtained using D_s^- \ell^+ combinations, where the D_s^- is fully reconstructed in the \phi \pi^-, K^*0 K^- and K^- K^0_S decay channels and partially reconstructed in the \phi \ell^- \nu(bar) X decay mode. A sample of \Lambda_b decays is obtained using \Lambda_c^+ \ell^- combinations, where the \Lambda_c^+ is fully reconstructed in its decay to a p K^- \pi^+ final state and partially reconstructed in the \Lambda \ell^+ \nu X decay channel. From 172 +/- 28 D_s^- \ell^+ combinations attributed to B^0_s decays, the measured lifetime is \tau(B^0_s) = 1.50 +0.16 -0.15 +/- 0.04 ps, where the errors are statistical and systematic, respectively. From the 129 +\- 25 \Lamda_c^+ \ell^- combinations attributed to \Lambda_b decays, the measured lifetime \tau(\Lambda_b) = 1.29 +0.24 -0.22 +/- 0.06 ps, where the errors are statistical and systematic, respectively.

Published
1998

49. Multi-photon final states in e+e− collisions at ∝s =130-172 GeV

Author

S. Petzold, G. D. Long, Tetsuro Mashimo, J. M. Roney, Anna Macchiolo, W. Gorn, Gabriella Pasztor, S. D. Bird, P. E. L. Clarke, W. Mohr, A. Posthaus, Matthias Schröder, G. A. Snow, S. R. Lautenschlager, H. A. Neal, M. Jimack, C. P. Ward, John Allison, B. Schmitt, K. Nagai, Eduardo Ros, N. K. Watson, S. M. Gascon-Shotkin, M. Thiergen, D. L. Rees, S. Söldner-Rembold, Kiyotomo Kawagoe, S. J. De Jong, Satoshi Mihara, Daniel Lellouch, Hildreth, P. Scharff-Hansen, C.J. Beeston, A. P. Wagner, Frank Fiedler, D. Axen, S. Komamiya, A. Jawahery, David G. Charlton, Gideon Bella, BT Bouwens, Rick J. Van Kooten, Eugene P. Gross, F. Wäckerle, Paolo Giacomelli, Takehiko Mori, H. J. Burckhart, Jacqueline Batley, M. Hansroul, Georges Azuelos, E. Tsur, C. M. Hawkes, S. H. Robertson, J. Goldberg, B. Nellen, N. J. Oldershaw, E. Lefebvre, J. Steuerer, A. M. Rossi, Isabel Marian Trigger, K. W. Bell, F. Scharf, German Martinez, Gideon Alexander, Otmar Biebel, Marco Verzocchi, R. Bartoldus, J. W. Gary, J. Palinkas, K. Sachs, F. Odorici, R. G. Kellogg, C. H. Shepherd-Themistocleous, R. J. Homer, D. S. Koetke, Csaba Hajdu, Stefano Marcellini, James Letts, A. D. Schaile, A. S. Turcot, P. Igo-Kemenes, Gy. Wolf, Shigenori Tanaka, Shlomo Dado, K. Ishii, K. R. Hossain, Paolo Capiluppi, P.A. Hart, H. Jeremie, H. O. Ogren, J. C. Hill, R. J. Teuscher, A. M. Smith, A. Michelini, V. Kartvelishvili, S. A. Robins, D. Rigby, R. J. Hemingway, Christoph Geich-Gimbel, D. R. Rust, J. Ludwig, B. C. Shen, K. Runge, P. Bock, J. R. Carter, P. I. Kayal, T. Behnke, Siegfried Bethke, G. Duckeck, W. G. Scott, P. G. Estabrooks, V. Gibson, H. G. Evans, P. Szymanski, M. J. Goodrick, Doug Gingrich, J. A. McKenna, I. Cohen, P. Jovanovic, I. J. Bloodworth, James Pinfold, I. Nakamura, R. Perez-Ochoa, E. do Couto e Silva, Ehud Duchovni, E. von Törne, C. R. Jones, Richard Nisius, U. Müller, T. Kress, Peter Krieger, D. G. Fong, Carla Sbarra, J. Gascon, P. Gagnon, Dezso Horvath, M. J. Losty, Sven Menke, Alessandro Montanari, A. J. Martin, K. Ackerstaff, P. M. Watkins, Takayuki Saeki, Jean-Arcady Meyer, Sherry Towers, T. Kawamoto, Marco Cuffiani, N. L. Rodning, A. Skillman, D. E. Hutchcroft, C. Dallapiccola, M. Kolrep, D. Karlen, Carsten Daniel Burgard, B. Poli, G. Mikenberg, O. Schaile, I. P. Duerdoth, Yoram Rozen, V. Zacek, A. Sittler, S. Orito, A. K. Honma, N. Altekamp, M. Foucher, Claudio Grandi, Peter Schleper, C. K. Hargrove, Zoltan Laszlo Trocsanyi, S. J. Hillier, Tara Shears, Robert McPherson, B. Stockhausen, P. Kyberd, P. Hüntemeyer, S. B. Anderson, F. K. Loebinger, D. J. Miller, A. H. Ball, Silvia Arcelli, M. F. Turner-Watson, Meirin Oan Evans, D. C. Imrie, Mathieu Doucet, M. Hapke, R. Bürgin, Marcello Mannelli, D. M. Strom, Matthew Herndon, Fabrizio Fabbri, M. Morii, Markus Schumacher, E.K.G. Sarkisian, H. Voss, G. W. Wilson, Peter R Hobson, Ivor Fleck, G. P. Siroli, S. Baumann, M. J. Pearce, U. Jost, R. Mir, Stan Bentvelsen, Christoph Schwick, J.A. Lauber, M. J. Oreglia, H. Mes, D Chrisman, E. A. Mckigney, S. Braibant, J. E. Conboy, S. D. Talbot, M. Sproston, Joleen Pater, Peter Sherwood, D. Zer-Zion, W. P. Lai, A. Fürtjes, Stefan Kluth, T. Geralis, R. D. Heuer, Shlomit Tarem, F. G. Oakham, Stefan Schmitt, Norbert Wermes, G. N. Patrick, E. L. Barberio, A. Klier, D. Eatough, R. Giacomelli, G. D. Lafferty, D. I. Futyan, Volker Blobel, P. Routenburg, T. R. Wyatt, Jochen Schieck, T. R. Junk, M. Gruwe, Hans-Christian Schultz-Coulon, Thomson, M. J. Kobel, P. Mättig, Shoji Asai, Stephen Lloyd, A. A. Faust, D. Glenzinski, Satoru Yamashita, Robert M Brown, Gregor Herten, R. Rylko, Robert Wayne Springer, M. Boutemeur, M. Fierro, J. E.G. Edwards, F. S. Merritt, T. P. Kokott, Dixit, P. W. Jeffreys, P. S. Wells, David E. Plane, B. Wilkens, J. E. Bloomer, T. Kobayashi, A. M. Lee, A. Macpherson, Richard Keeler, P. Vikas, R. J. Sobie, Robert Lahmann, R. Howard, J. S. White, Alexander Oh, J. E. Pilcher, D. Lanske, J. Bechtluft, M. Hauschild, C. Markus, G. T. Jones, E. H. Vokurka, P R Poffenberger, J. Grunhaus, C. Hartmann, H. Fischer, O. Runolfsson, Alan Watson, Matthew Jones, Reda Tafirout, Klaus Kurt Desch, W. R. Gibson, A. Joly, Lorne Levinson, B. W. Kennedy, N. I. Geddes, Roger Barlow, K. Stephens, W.John McDonald, D. Lazic, D. R. Ward, U. Ruppel, M. R. Ingram, C. Y. Chang, P. Taras, G. Yekutieli, Allen Mincer, Marcello Fanti, Julie Kirk, P. Pfeifenschneider, A. A. Carter, Ron Folman, J. Patt, André Schöning, G. G. Hanson, G.Marco Dallavalle, P. Utzat, Beatrix Dienes, L. Brigliadori, G. Giacomelli, Daniele Bonacorsi, O. C. Cooke, S. W. O'Neale, R. Davies, P. Schenk, K. J. Anderson, J. von Krogh, Frans Meijers, R. J. Hawkings, L. A. del Pozo, A. Biguzzi, A. Rooke, J. G. Layter, T. J. McMahon, R. K. Carnegie, M. Bobinski, J. A. Wilson, J.P. Martin, A. N. Bell, K. Stoll, and Andris Skuja

Subjects
Nuclear physics, Physics, Particle physics, Angular distribution, Physics and Astronomy (miscellaneous), Electron–positron annihilation, Engineering (miscellaneous)
Published
1998

50. Search for the Bc meson in hadronic Z0 decays

Author

K Ackerstaff, G Alexander, J Allison, N Altekamp, K.J Anderson, S Anderson, S Arcelli, S Asai, S.F Ashby, D Axen, G Azuelos, A.H Ball, E Barberio, R.J Barlow, R Bartoldus, J.R Batley, S Baumann, J Bechtluft, C Beeston, T Behnke, A.N Bell, K.W Bell, G Bella, S Bentvelsen, S Bethke, S Betts, O Biebel, A Biguzzi, S.D Bird, V Blobel, I.J Bloodworth, J.E Bloomer, M Bobinski, P Bock, D Bonacorsi, M Boutemeur, S Braibant, L Brigliadori, R.M Brown, H.J Burckhart, C Burgard, R Bürgin, P Capiluppi, R.K Carnegie, A.A Carter, J.R Carter, C.Y Chang, D.G Charlton, D Chrisman, P.E.L Clarke, I Cohen, J.E Conboy, O.C Cooke, C Couyoumtzelis, R.L Coxe, M Cuffiani, S Dado, C Dallapiccola, G.M Dallavalle, R Davis, S De Jong, L.A del Pozo, K Desch, B Dienes, M.S Dixit, M Doucet, E Duchovni, G Duckeck, I.P Duerdoth, D Eatough, J.E.G Edwards, P.G Estabrooks, H.G Evans, M Evans, F Fabbri, A Fanfani, M Fanti, A.A Faust, L Feld, F Fiedler, M Fierro, H.M Fischer, I Fleck, R Folman, D.G Fong, M Foucher, A Fürtjes, D.I Futyan, P Gagnon, J.W Gary, J Gascon, S.M Gascon-Shotkin, N.I Geddes, C Geich-Gimbel, T Geralis, G Giacomelli, P Giacomelli, R Giacomelli, V Gibson, W.R Gibson, D.M Gingrich, D Glenzinski, J Goldberg, M.J Goodrick, W Gorn, C Grandi, E Gross, J Grunhaus, M Gruwé, C Hajdu, G.G Hanson, M Hansroul, M Hapke, C.K Hargrove, P.A Hart, C Hartmann, M Hauschild, C.M Hawkes, R Hawkings, R.J Hemingway, M Herndon, G Herten, R.D Heuer, M.D Hildreth, J.C Hill, S.J Hillier, P.R Hobson, A Hocker, R.J Homer, A.K Honma, D Horváth, K.R Hossain, R Howard, P Hüntemeyer, D.E Hutchcroft, P Igo-Kemenes, D.C Imrie, M.R Ingram, K Ishii, A Jawahery, P.W Jeffreys, H Jeremie, M Jimack, A Joly, C.R Jones, G Jones, M Jones, U Jost, P Jovanovic, T.R Junk, J Kanzaki, D Karlen, V Kartvelishvili, K Kawagoe, T Kawamoto, P.I Kayal, R.K Keeler, R.G Kellogg, B.W Kennedy, J Kirk, A Klier, S Kluth, T Kobayashi, M Kobel, D.S Koetke, T.P Kokott, M Kolrep, S Komamiya, T Kress, P Krieger, J von Krogh, P Kyberd, G.D Lafferty, R Lahmann, W.P Lai, D Lanske, J Lauber, S.R Lautenschlager, J.G Layter, D Lazic, A.M Lee, E Lefebvre, D Lellouch, J Letts, L Levinson, S.L Lloyd, F.K Loebinger, G.D Long, M.J Losty, J Ludwig, D Lui, A Macchiolo, A Macpherson, M Mannelli, S Marcellini, C Markopoulos, C Markus, A.J Martin, J.P Martin, G Martinez, T Mashimo, P Mättig, W.J McDonald, J McKenna, E.A Mckigney, T.J McMahon, R.A McPherson, F Meijers, S Menke, F.S Merritt, H Mes, J Meyer, A Michelini, G Mikenberg, D.J Miller, A Mincer, R Mir, W Mohr, A Montanari, T Mori, U Müller, S Mihara, K Nagai, I Nakamura, H.A Neal, B Nellen, R Nisius, S.W O'Neale, F.G Oakham, F Odorici, H.O Ogren, A Oh, N.J Oldershaw, M.J Oreglia, S Orito, J Pálinkás, G Pásztor, J.R Pater, G.N Patrick, J Patt, R Perez-Ochoa, S Petzold, P Pfeifenschneider, J.E Pilcher, J Pinfold, D.E Plane, P Poffenberger, B Poli, A Posthaus, C Rembser, S Robertson, S.A Robins, N Rodning, J.M Roney, A Rooke, A.M Rossi, P Routenburg, Y Rozen, K Runge, O Runolfsson, U Ruppel, D.R Rust, R Rylko, K Sachs, T Saeki, W.M Sang, E.K.G Sarkisyan, C Sbarra, A.D Schaile, O Schaile, F Scharf, P Scharff-Hansen, J Schieck, P Schleper, B Schmitt, S Schmitt, A Schöning, M Schröder, H.C Schultz-Coulon, M Schumacher, C Schwick, W.G Scott, T.G Shears, B.C Shen, C.H Shepherd-Themistocleous, P Sherwood, G.P Siroli, A Sittler, A Skillman, A Skuja, A.M Smith, G.A Snow, R Sobie, S Söldner-Rembold, R.W Springer, M Sproston, K Stephens, J Steuerer, B Stockhausen, K Stoll, D Strom, R Ströhmer, P Szymanski, R Tafirout, S.D Talbot, S Tanaka, P Taras, S Tarem, R Teuscher, M Thiergen, M.A Thomson, E von Törne, E Torrence, S Towers, I Trigger, Z Trócsányi, E Tsur, A.S Turcot, M.F Turner-Watson, P Utzat, R Van Kooten, M Verzocchi, P Vikas, E.H Vokurka, H Voss, F Wäckerle, A Wagner, C.P Ward, D.R Ward, P.M Watkins, A.T Watson, N.K Watson, P.S Wells, N Wermes, J.S White, B Wilkens, G.W Wilson, J.A Wilson, T.R Wyatt, S Yamashita, G Yekutieli, V Zacek, and D Zer-Zion

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Muon, Meson, 010308 nuclear & particles physics, High Energy Physics::Phenomenology, Hadron, FOS: Physical sciences, Electron, 01 natural sciences, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, High Energy Physics::Experiment, 010306 general physics, Particle Physics - Experiment
Abstract

A search for decays of the B_c meson was performed using data collected from 1990-1995 with the OPAL detector on or near the Z peak at LEP. The decay channels B_c^+ -> J/psi pi^+, B_c^+ -> J/psi a_1^+ and B_c^+ -> J/psi ell^+ nu were investigated, where ell denotes an electron or a muon. Two candidates are observed in the mode B_c^+ -> J/psi pi^+, with an estimated background of (0.63 +/- 0.20) events. The weighted mean of the masses of the two candidates is (6.32 +/- 0.06) GeV/c^2, which is consistent with the predicted mass of the B_c meson. One candidate event is observed in the mode B_c^+ -> J/psi ell^+ nu with an estimated background of (0.82 +/- 0.19) events. No candidate events are observed in the B_c^+ -> J/psi a_1^+ decay mode, with an estimated background of (1.10 +/- 0.22) events. Upper bounds at the 90% confidence level are set on the production rates for these processes., 18 pages, LaTeX, uses a4p.sty, 6 eps figures included, submitted to Phys. Lett. B

Published
1998

Catalog

Books, media, physical & digital resources
See catalog results