Lothar At Bauerdick

Particle physics has an ambitious and broad experimental programme for the coming decades. This programme requires large investments in detector hardware, either to build new facilities and experiments, or to upgrade existing ones. Similarly, it requires commensurate investment in the R&D of software to acquire, manage, process, and analyse the shear amounts of data to be recorded. In planning for the HL-LHC in particular, it is critical that all of the collaborating stakeholders agree on the software goals and priorities, and that the efforts complement each other. In this spirit, this white paper describes the R&D activities required to prepare for this software upgrade.

In order to extend the tracking acceptance, to improve the primary and secondary vertex reconstruction and thus enhancing the tagging capabilities for short lived particles, the ZEUS experiment at the HERA Collider at DESY installed a silicon strip vertex detector. The barrel part of the detector is a 63 cm long cylinder with silicon sensors arranged around an elliptical beampipe. The forward part consists of four circular shaped disks. In total just over 200k channels are read out using 2.9m2 of silicon. In this report a detailed overview of the design and construction of the detector is given and the performance of the completed system is reviewed.

While the LHC data movement systems have demonstrated the ability to move data at the necessary throughput, we have identified two weaknesses: the latency for physicists to access data and the complexity of the tools involved. To address these, both ATLAS and CMS have begun to federate regional storage systems using Xrootd. Xrootd, referring to a protocol and implementation, allows us to provide data access to all disk-resident data from a single virtual endpoint. This "redirector" discovers the actual location of the data and redirects the client to the appropriate site. The approach is particularly advantageous since typically the redirection requires much less than 500 milliseconds and the Xrootd client is conveniently built into LHC physicists' analysis tools. Currently, there are three regional storage federations - a US ATLAS region, a European CMS region, and a US CMS region. The US ATLAS and US CMS regions include their respective Tier 1, Tier 2 and some Tier 3 facilities; a large percentage of experimental data is available via the federation. Additionally, US ATLAS has begun studying low-latency regional federations of close-by sites. From the base idea of federating storage behind an endpoint, the implementations and use cases diverge. The CMS software framework is capable of efficiently processing data over high-latency links, so using the remote site directly is comparable to accessing local data. The ATLAS processing model allows a broad spectrum of user applications with varying degrees of performance with regard to latency; a particular focus has been optimizing n-tuple analysis. Both VOs use GSI security. ATLAS has developed a mapping of VOMS roles to specific file system authorizations, while CMS has developed callouts to the site's mapping service. Each federation presents a global namespace to users. For ATLAS, the global-to-local mapping is based on a heuristic-based lookup from the site's local file catalog, while CMS does the mapping based on translations given in a configuration file. We will also cover the latest usage statistics and interesting use cases that have developed over the previous 18 months.

The Grid2003 Project has deployed a multivirtual organization, application-driven grid laboratory (Grid3) that has sustained for several months the production-level services required by physics experiments of the Large Hadron Collider at CERN (ATLAS and CMS), the Sloan Digital Sky Survey project, the gravitational wave search experiment LIGO, the BTeV experiment at Fermilab, as well as applications in molecular structure analysis and genome analysis, and computer science research projects in such areas as job and data scheduling. The deployed infrastructure has been operating since November 2003 with 27 sites, a peak of 2800 processors, work loads from 10 different applications exceeding 1300 simultaneous jobs, and data transfers among sites of greater than 2 TB/day. We describe the principles that have guided the development of this unique infrastructure and the practical experiences that have resulted from its creation and use. We discuss application requirements for grid services deployment and configuration, monitoring infrastructure, application performance, metrics, and operational experiences. We also summarize lessons learned.

Following the success of the XRootd-based US CMS data federation, the AAA project investigated extensions of the federation architecture by developing two sample implementations of an XRootd, disk-based, caching proxy. The first one simply starts fetching a whole file as soon as a file open request is received and is suitable when completely random file access is expected or it is already known that a whole file be read. The second implementation supports on-demand downloading of partial files. Extensions to the Hadoop Distributed File System have been developed to allow for an immediate fallback to network access when local HDFS storage fails to provide the requested block. Both cache implementations are in pre-production testing at UCSD.

The Grid2003 Project has deployed a multivirtual organization, application-driven grid laboratory ("Grid3") that has sustained for several months the production-level services required by physics experiments of the Large Hadron Collider at CERN (ATLAS and CMS), the Sloan Digital Sky Survey project, the gravitational wave search experiment LIGO, the BTeV experiment at Fermilab, as well as applications in molecular structure analysis and genome analysis, and computer science research projects in such areas as job and data scheduling. The deployed infrastructure has been operating since November 2003 with 27 sites, a peak of 2800 processors, work loads from 10 different applications exceeding 1300 simultaneous jobs, and data transfers among sites of greater than 2 TB/day. We describe the principles that have guided the development of this unique infrastructure and the practical experiences that have resulted from its creation and use. We discuss application requirements for grid services deployment and configuration, monitoring infrastructure, application performance, metrics, and operational experiences. We also summarize lessons learned.

From a sample of 150 000 hadronic Z decays collected with the ALEPH detector at LEP, events containing prompt leptons are used to measure the forward-backward asymmetries for the channels Z→bb and Z→cc, giving the results AFBb=0.126±0.028±0.012 and AFBc=0.064±0.039±0.030. These asymmetries correspond to the value of effective electroweak mixing angle at the Z mass sin2θW(mZ2) = 0.2262±0.0053.

Historically, high energy physics computing has been performed on large purpose-built computing systems. These began as single-site compute facilities, but have evolved into the distributed computing grids used today. Recently, there has been an exponential increase in the capacity and capability of commercial clouds. Cloud resources are highly virtualized and intended to be able to be flexibly deployed for a variety of computing tasks. There is a growing nterest among the cloud providers to demonstrate the capability to perform large-scale scientific computing. In this paper, we discuss results from the CMS experiment using the Fermilab HEPCloud facility, which utilized both local Fermilab resources and virtual machines in the Amazon Web Services Elastic Compute Cloud. We discuss the planning, technical challenges, and lessons learned involved in performing physics workflows on a large-scale set of virtualized resources. In addition, we will discuss the economics and operational efficiencies when executing workflows both in the cloud and on dedicated resources.

The lifetimes of the B0 and B− mesons have been measured with the ALEPH detector at LEP. Semileptonic decays of B0 and B− mesons were partially reconstructed by identifying events containing a lepton with an associated D∗+orD0 meson. The proper time of the B meson was estimated from the measured decay length and the momentum and mass of the D-lepton system. A fit to the proper time of 77 D∗+ℓ− and 77 D0ℓ− candidates, combined with a constraint on the lifetime ratio (τ−τ0) arising from the relative rates of observed D∗+ℓ− and D0ℓ− events, yielded the following lifetimes: τ0=1.52−0.18+0.20(stat.)−0.13+0.07(syst.)ps, τ−= 1.47−0.19+0.22(stat.)−0.14+0.15(syst.)ps,τ−τ0= 0.96−0.15+0.19(stat.)−0.12+0.18(syst.).

Using a missing energy tag, evidence is presented for the decay b → τ−ντX, and its branching ratio is measured to be (4.08 ± 0.76 ± 0.62)%.

The HL-LHC run is anticipated to start at the end of this decade and will pose a significant challenge for the scale of the HEP software and computing infrastructure. The mission of the U.S. CMS Software & Computing Operations Program is to develop and operate the software and computing resources necessary to process CMS data expeditiously and to enable U.S. physicists to fully participate in the physics of CMS. We have developed a strategic plan to prioritize R&D efforts to reach this goal for the HL-LHC. This plan includes four grand challenges: modernizing physics software and improving algorithms, building infrastructure for exabyte-scale datasets, transforming the scientific data analysis process and transitioning from R&D to operations. We are involved in a variety of R&D projects that fall within these grand challenges. In this talk, we will introduce our four grand challenges and outline the R&D program of the U.S. CMS Software & Computing Operations Program.

In 450 000 hadronic Z decays recorded with the ALEPH detector at LEP, the yields of Ds−ℓ+ and Λc+ℓ− combinations have been measured. 16.0 ± 4.3 Ds−ℓ+ combinations were observed in the Ds− → ππ− channel and 17.0 ± 4.5 combinations were observed in the Ds−→K∗0K− channel. 21.0 ± 5.0 Λc+ℓ− combinations were observed, with the Λc+ reconstructed in the decay mode Λc+ → pK−π+. These events provide evidence for the decays Bs→Ds−Xℓ+νandΛb→ Λc+Xℓ−ν. Assuming that the Bs and Λb semileptonic decays are dominantly three-body, these observed yields, after background subtraction, translate into the following product branching ratios: Br(b→Bs)Br(Bs→Ds−Xℓ+ν) = 0.040±0.011−0.012+0.010, Br(b→ Λb)Br(Λb→ Λc+Xℓ−ν) = 0.030±0.007±0.009.

The production of high energy isolated photons in hadronic Z decays is measured with the ALEPH detector at LEP using a sample of 180 000 hadronic events. Such photons are mainly radiated by quarks, thus giving direct insights into the early parton showering mechanism. The observed rate is compared with a QCD calculation of final state radiation from quarks.

Results on B0−B0 mixing in e+e− annihilation at LEP are reported. A new method is used, where the charge of one b quark is tagged by a high-p, high-p⊥ electron or muon, and the charge of the other is extracted from the momentum-weighted average of the charges of jet fragments. Based on the analysis of 180 000 hadronic Z decays produced in the ALEPH detector, ⨍dχd+0.72⨍sχs=0.113±0.018(stat.)±0.027(syst.) is obtained. Combining this result with the ALEPH dipleton measurement yields χ=0.129±0.022.

Fireworks is a CMS event display which is specialized for the physics studies case. This specialization allows us to use a stylized rather than 3D-accurate representation when appropriate. Data handling is greatly simplified by using only reconstructed information and ideal geometry. Fireworks provides an easy-to-use interface which allows a physicist to concentrate only on the data in which he is interested. Data is presented via graphical and textual views. Fireworks is built using the Eve subsystem of the CERN ROOT project and CMS's FWLite project. The FWLite project was part of CMS's recent code redesign which separates data classes into libraries separate from algorithms producing the data and uses ROOT directly for C++ object storage, thereby allowing the data classes to be used directly in ROOT.

The CMS experiment expects to manage several Pbytes of data each year during the LHC programme, distributing them over many computing sites around the world and enabling data access at those centers for analysis. CMS has identified the distributed sites as the primary location for physics analysis to support a wide community with thousands potential users. This represents an unprecedented experimental challenge in terms of the scale of distributed computing resources and number of user. An overview of the computing architecture, the software tools and the distributed infrastructure is reported. Summaries of the experience in establishing efficient and scalable operations to get prepared for CMS distributed analysis are presented, followed by the user experience in their current analysis activities.

Particle physics has an ambitious and broad experimental programme for the coming decades. This programme requires large investments in detector hardware, either to build new facilities and experiments, or to upgrade existing ones. Similarly, it requires commensurate investment in the R&D of software to acquire, manage, process, and analyse the shear amounts of data to be recorded. In planning for the HL-LHC in particular, it is critical that all of the collaborating stakeholders agree on the software goals and priorities, and that the efforts complement each other. In this spirit, this white paper describes the R&D activities required to prepare for this software upgrade.

Contact interactions are searched for using the differential cross sections for the reactionse + e −→e + e −,e + e −→µ + µ −,e + e −→τ + τ − ande + e −→γγ measured at 12 energies around theZ peak and corresponding to about 20 pb−1 of cumulated luminosity. Four-fermion contact term models assuming various chiralities of lepton currents are fitted to the lepton data and lower limits on the energy scale Λ of such terms are set at 95% c.l. The limits vary in the range 0.9–4.7 TeV, depending on the model and on the lepton flavour. Theeeγγ contact terms are searched for assuming various chiralities. Limits on the energy scale Λ between 79 and 130 GeV are extracted from the data. The results are compared and combined with those reported at lower energies.

Historically high energy physics computing has been performed on large purpose-built computing systems. In the beginning there were single site computing facilities, which evolved into the Worldwide LHC Computing Grid (WLCG) used today. The vast majority of the WLCG resources are used for LHC computing and the resources are scheduled to be continuously used throughout the year. In the last several years there has been an explosion in capacity and capability of commercial and academic computing clouds. Cloud resources are highly virtualized and intended to be able to be flexibly deployed for a variety of computing tasks. There is a growing interest amongst the cloud providers to demonstrate the capability to perform large scale scientific computing. In this presentation we will discuss results from the CMS experiment using the Fermilab HEPCloud Facility, which utilized both local Fermilab resources and Amazon Web Services (AWS). The goal was to work with AWS through a matching grant to demonstrate a sustained scale approximately equal to half of the worldwide processing resources available to CMS. We will discuss the planning and technical challenges involved in organizing the most IO intensive CMS workflows on a large-scale set of virtualized resource provisioned by the Fermilab HEPCloud. We will describe the data handling and data management challenges. Also, we will discuss the economic issues and cost and operational efficiency comparison to our dedicated resources. At the end we will consider the changes in the working model of HEP computing in a domain with the availability of large scale resources scheduled at peak times.

The CMS experiment is preparing for LHC data taking in several computing preparation activities. In distributed data transfer tests, in early 2007 a traffic load generator infrastructure was designed and deployed, to equip the WLCG Tiers which support the CMS Virtual Organization with a means for debugging, load-testing and commissioning data transfer routes among CMS Computing Centres. The LoadTest is based upon PhEDEx as a reliable, scalable dataset replication system. In addition, a Debugging Data Transfers (DDT) Task Force was created to coordinate the debugging of data transfer links in the preparation period and during the Computing Software and Analysis challenge in 2007 (CSA07). The task force aimed to commission most crucial transfer routes among CMS tiers by designing and enforcing a clear procedure to debug problematic links. Such procedure aimed to move a link from a debugging phase in a separate and independent environment to a production environment when a set of agreed conditions are achieved for that link. The goal was to deliver one by one working transfer routes to Data Operations. The experiences with the overall test transfers infrastructure within computing challenges - as in the WLCG Common-VO Computing Readiness Challenge (CCRC’08) - as well as in daily testing and debugging activities are reviewed and discussed, and plans for the future are presented.

During the last year the CMS experiment engaged in consolidation of its existing event display programs. The core of the new system is based on the Fireworks event display program which was by-design directly integrated with the CMS Event Data Model (EDM) and the light version of the software framework (FWLite). The Event Visualization Environment (EVE) of the ROOT framework is used to manage a consistent set of 3D and 2D views, selection, user-feedback and user-interaction with the graphics windows; several EVE components were developed by CMS in collaboration with the ROOT project. In event display operation simple plugins are registered into the system to perform conversion from EDM collections into their visual representations which are then managed by the application. Full event navigation and filtering as well as collection-level filtering is supported. The same data-extraction principle can also be applied when Fireworks will eventually operate as a service within the full software framework.

As it enters adolescence the Open Science Grid (OSG) is bringing a maturing fabric of Distributed High Throughput Computing (DHTC) services that supports an expanding HEP community to an increasingly diverse spectrum of domain scientists. Working closely with researchers on campuses throughout the US and in collaboration with national cyberinfrastructure initiatives, we transform their computing environment through new concepts, advanced tools and deep experience. We discuss examples of these including: the pilot-job overlay concepts and technologies now in use throughout OSG and delivering 1.4 Million CPU hours/day; the role of campus infrastructures- built out from concepts of sharing across multiple local faculty clusters (made good use of already by many of the HEP Tier-2 sites in the US); the work towards the use of clouds and access to high throughput parallel (multi-core and GPU) compute resources; and the progress we are making towards meeting the data management and access needs of non-HEP communities with general tools derived from the experience of the parochial tools in HEP (integration of Globus Online, prototyping with IRODS, investigations into Wide Area Lustre). We will also review our activities and experiences as HTC Service Provider to the recently awarded NSF XD XSEDE project, the evolution of the US NSF TeraGrid project, and how we are extending the reach of HTC through this activity to the increasingly broad national cyberinfrastructure. We believe that a coordinated view of the HPC and HTC resources in the US will further expand their impact on scientific discovery.

The discovery of the Higgs boson by the Large Hadron Collider (LHC) has garnered international attention. In addition to this singular result, the LHC may also uncover other fundamental particles, including dark matter. Much of this research is being done on data from one of the LHC experiments, the Compact Muon Solenoid (CMS). The CMS experiment was able to capture data at higher sampling frequencies than planned during the 2012 LHC operational period. The resulting data had been parked, waiting to be processed on CMS computers. While CMS has significant compute resources, by partnering with SDSC to incorporate Gordon into the CMS workflow, analysis of the parked data was completed months ahead of schedule. This allows scientists to review the results more quickly, and could guide future plans for the LHC.

The present understanding of the factors which limit the rφ measurement accuracy of the ALEPH time projection chamber is outlined. The resolution for high-momentum tracks is shown to be dominated by the E × B and angular affects.

During spring and summer of 2011, CMS deployed Xrootd-based access for all US T1 and T2 sites. This allows for remote access to all experiment data on disk in the US. It is used for user analysis, visualization, running of jobs at computing sites when data is not available at local sites, and as a fail-over mechanism for data access in jobs. Monitoring of this Xrootd infrastructure is implemented on three levels. Basic service and data availability checks are performed by Nagios probes. The second level uses Xrootd's "summary data" stream; this data is aggregated from all sites and fed into a MonALISA service providing visualization and storage. The third level uses Xrootd's "detailed monitoring" stream, which includes detailed information about users, opened files and individual data transfers. A custom application was developed to process this information. It currently provides a real-time view of the system usage and can store data into ROOT files for detailed analysis. Detailed monitoring allows us to determine dataset popularity and to detect abuses of the system, including sub-optimal usage of the Xrootd protocol and the ROOT prefetching mechanism.

The HL-LHC run is anticipated to start at the end of this decade and will pose a significant challenge for the scale of the HEP software and computing infrastructure. The mission of the U.S. CMS Software & Computing Operations Program is to develop and operate the software and computing resources necessary to process CMS data expeditiously and to enable U.S. physicists to fully participate in the physics of CMS. We have developed a strategic plan to prioritize R&D efforts to reach this goal for the HL-LHC. This plan includes four grand challenges: modernizing physics software and improving algorithms, building infrastructure for exabyte-scale datasets, transforming the scientific data analysis process and transitioning from R&D to operations. We are involved in a variety of R&D projects that fall within these grand challenges. In this talk, we will introduce our four grand challenges and outline the R&D program of the U.S. CMS Software & Computing Operations Program.

The reactions e+e− → hZ∗ande+e− → hA have been used to search for the neutral Higgs bosons h and A of the MSSM in the case where the CP-odd A is lighter than 2mμ, taking into account the large h → AA decay branching ratio. No signal was found in the data sample collected until the end of 1991 by the ALEPH experiment at LEP. For tan β ⩾, mA < 2mμ is excluded at 95% CL for any mh.

At the heart of experimental high energy physics (HEP) is the development of facilities and instrumentation that provide sensitivity to new phenomena. Our understanding of nature at its most fundamental level is advanced through the analysis and interpretation of data from sophisticated detectors in HEP experiments. The goal of data analysis systems is to realize the maximum possible scientific potential of the data within the constraints of computing and human resources in the least time. To achieve this goal, future analysis systems should empower physicists to access the data with a high level of interactivity, reproducibility and throughput capability. As part of the HEP Software Foundation Community White Paper process, a working group on Data Analysis and Interpretation was formed to assess the challenges and opportunities in HEP data analysis and develop a roadmap for activities in this area over the next decade. In this report, the key findings and recommendations of the Data Analysis and Interpretation Working Group are presented.

Memorial Volume for Jack Steinberger, pp. 161-180 (2022) No AccessImproved measurements of electroweak parameters from Z decays into fermion pairsALEPH Collaboration, D. Decamp, B. Deschizeaux, C. Goy, J.-P. Lees, M.-N. Minard, R. Alemany, J.M. Crespo, M. Delfino, E. Fernandez, V. Gaitan, LI. Garrido, Ll.M. Mir, A. Pacheco, M.G. Catanesi, D. Creanza, M. de Palma, A. Farilla, G. Iaselli, G. Maggi, M. Maggi, S. Natali, S. Nuzzo, M. Quattromini, A. Ranieri, G. Raso, F. Romano, F. Ruggieri, G. Selvaggi, L. Silvestris, P. Tempesta, G. Zito, Y. Gao, H. Hu, D. Huang, X. Huang, J. Lin, J. Lou, C. Qiao, T. Ruan, T. Wang, Y. Xie, D. Xu, R. Xu, J. Zhang, W. Zhao, W.B. Atwood, L.A.T. Bauerdick, F. Bird, E. Blucher, G. Bonvicini, F. Bossi, J. Boudreau, D. Brown, T.H. Burnett, H. Drevermann, R.W. Forty, C. Grab, R. Hagelberg, S. Haywood, J. Hilgart, B. Jost, M. Kasemann, J. Knobloch, A. Lacourt, E. Lançon, I. Lehraus, T. Lohse, A. Lusiani, A. Marchioro, M. Martinez, P. Mato, S. Menary, A. Minten, A. Miotto, R. Miquel, H.-G. Moser, J. Nash, P. Palazzi, F. Ranjard, G. Redlinger, A. Roth, J. Rothberg, H. Rotscheidt, M. Saich, R.St. Denis, D. Schlatter, M. Takashima, M. Talby, W. Tejessy, H. Wachsmuth, S. Wasserbaech, S. Wheeler, W. Wiedenmann, W. Witzeling, J. Wotschack, Z. Ajaltouni, M. Bardadin-Otwinowska, R. El Fellous, A. Falvard, P. Gay, J. Harvey, P. Henrard, J. Jousset, B. Michel, J.-C. Montret, D. Pallin, P. Perret, J. Proriol, F. Prulhière, G. Stimpfl, J.D. Hansen, J.R. Hansen, P.H. Hansen, R. Møllerud, B.S. Nilsson, I. Efthymiopoulos, E. Simopoulou, A. Vayaki, J. Badier, A. Blondel, G. Bonneaud, J. Bourotte, F. Braems, J.C. Brient, G. Fouque, A. Gamess, R. Guirlet, S. Orteu, A. Rosowsky, A. Rougé, M. Rumpf, R. Tanaka, H. Videau, D.J. Candlin, E. Veitch, G. Parrini, M. Corden, C. Georgiopoulos, M. Ikeda, J. Lannutti, D. Levinthal, M. Mermikides, L. Sawyer, A. Antonelli, R. Baldini, G. Bencivenni, G. Bologna, P. Campana, G. Capon, F. Cerutti, V. Chiarella, B. D’Ettorre-Piazzoli, G. Felici, P. Laurelli, G. Mannocchi, F. Murtas, G.P. Murtas, G. Nicoletti, L. Passalacqua, M. Pepe-Altarelli, P. Picchi, P. Zografou, B. Altoon, O. Boyle, A.W. Halley, I. ten Have, J.L. Hearns, J.G. Lynch, W.T. Morton, C. Raine, J.M. Scarr, K. Smith, A.S. Thompson, R.M. Turnbull, B. Brandl, O. Braun, R. Geiges, C. Geweniger, P. Hanke, V. Hepp, E.E. Kluge, Y. Maumary, A. Putzer, B. Rensch, A. Stahl, K. Tittel, M. Wunsch, A.T. Belk, R. Beuselinck, D.M. Binnie, W. Cameron, M. Cattaneo, P.J. Dornan, S. Dugeay, A.M. Greene, J.F. Hassard, N.M. Lieske, S.J. Patton, D.G. Payne, M.J. Phillips, J.K. Sedgbeer, G. Taylor, I.R. Tomalin, A. G. Wright, P. Girtler, D. Kuhn, G. Rudolph, C.K. Bowdery, T.J. Brodbeck, A.J. Finch, F. Foster, G. Hughes, N.R. Keemer, M. Nuttall, A. Patel, B.S. Rowlingson, T. Sloan, S.W. Snow, E.P. Whelan, T. Barczewski, K. Kleinknecht, J. Raab, B. Renk, S. Roehn, H.-G. Sander, M. Schmelling, H. Schmidt, F. Steeg, S.M. Walther, B. Wolf, J-P. Albanese, J-J. Aubert, C. Benchouk, V. Bernard, A. Bonissent, D. Courvoisier, F. Etienne, S. Papalexiou, P. Payre, B. Pietrzyk, Z. Qian, H. Becker, W. Blum, P. Cattaneo, G. Cowan, B. Dehning, H. Dietl, F. Dydak, M. Fernandez-Bosman, T. Hansl-Kozanecka, A. Jahn, W. Kozanecki, E. Lange, J. Lauber, G. Lütjens, G. Lutz, W. Männer, Y. Pan, R. Richter, J. Schröder, A.S. Schwarz, R. Settles, U. Stierlin, J. Thomas, G. Wolf, V. Bertin, J. Boucrot, O. Callot, X. Chen, A. Cordier, M. Davier, G. Ganis, J.-F. Grivaz, Ph. Heusse, P. Janot, D.W. Kim, F. Le Diberder, J. Lefrançois, A.-M. Lutz, J.-J. Veillet, I. Videau, Z. Zhang, F. Zomer, D. Abbaneo, S.R. Amendolia, G. Bagliesi, G. Batignani, L. Bosisio, U. Bottigli, C. Bradaschia, M. Carpinelli, M.A. Ciocci, R. Dell’Orso, I. Ferrante, F. Fidecaro, L. Foà, E. Focardi, F. Forti, C. Gatto, A. Giassi, M.A. Giorgi, F. Ligabue, E.B. Mannelli, P.S. Marrocchesi, A. Messineo, L. Moneta, F. Palla, G. Sanguinetti, J. Steinberger, R. Tenchini, G. Tonelli, G. Triggiani, C. Vannini, A. Venturi, P.G. Verdini, J. Walsh, J.M. Carter, M.G. Green, P.V. March, T. Medcalf, I.S. Quazi, J.A. Strong, R.M. Thomas, L.R. West, T. Wildish, D.R. Botterill, R.W. Clifft, T.R. Edgecock, M. Edwards, S.M. Fisher, T.J. Jones, P.R. Norton, D.P. Salmon, J.C. Thompson, B. Bloch-Devaux, P. Colas, C. Klopfenstein, E. Locci, S. Loucatos, E. Monnier, P. Perez, J.A. Perlas, F. Perrier, J. Rander, J.-F. Renardy, A. Roussarie, J.-P. Schuller, J. Schwindling, B. Vallage, J.G. Ashman, C.N. Booth, C. Buttar, R. Carney, S. Cartwright, F. Combley, M. Dinsdale, M. Dogru, F. Hatfield, J. Martin, D. Parker, P. Reeves, L.F. Thompson, E. Barberio, S. Brandt, H. Burkhardt, C. Grupen, H. Meinhard, L. Mirabito, U. Schäfer, H. Seywerd, G. Apollinari, G. Giannini, B. Gobbo, F. Liello, F. Ragusa, L. Rolandi, U. Stiegler, L. Bellantoni, X. Chen, D. Cinabro, J.S. Conway, D.F. Cowen, Z. Feng, D.P.S. Ferguson, Y.S. Gao, J. Grahl, J.L. Harton, J.E. Jacobsen, R.C. Jared, R.P. Johnson, B.W. Le Claire, Y.B. Pan, J.R. Pater, Y. Saadi, V. Sharma, Z.H. Shi, Y.H. Tang, A.M. Walsh, J.A. Wear, F.V. Weber, M.H. Whitney, Sau Lan Wu and G. ZobernigALEPH Collaboration, D. DecampLaboratoire de Physique des Particules (LAPP), IN2P3-CNRS, F-74019 Annecy-le-Vieux Cedex, France, B. DeschizeauxLaboratoire de Physique des Particules (LAPP), IN2P3-CNRS, F-74019 Annecy-le-Vieux Cedex, France, C. GoyLaboratoire de Physique des Particules (LAPP), IN2P3-CNRS, F-74019 Annecy-le-Vieux Cedex, France, J.-P. LeesLaboratoire de Physique des Particules (LAPP), IN2P3-CNRS, F-74019 Annecy-le-Vieux Cedex, France, M.-N. MinardLaboratoire de Physique des Particules (LAPP), IN2P3-CNRS, F-74019 Annecy-le-Vieux Cedex, France, R. AlemanyLaboratorio de Fisica de Altas Energías, Universidad Autonoma de Barcelona, E-08193 Bellaterra (Barcelona), Spain, J.M. CrespoLaboratorio de Fisica de Altas Energías, Universidad Autonoma de Barcelona, E-08193 Bellaterra (Barcelona), Spain, M. DelfinoLaboratorio de Fisica de Altas Energías, Universidad Autonoma de Barcelona, E-08193 Bellaterra (Barcelona), Spain, E. FernandezLaboratorio de Fisica de Altas Energías, Universidad Autonoma de Barcelona, E-08193 Bellaterra (Barcelona), Spain, V. GaitanLaboratorio de Fisica de Altas Energías, Universidad Autonoma de Barcelona, E-08193 Bellaterra (Barcelona), Spain, LI. GarridoLaboratorio de Fisica de Altas Energías, Universidad Autonoma de Barcelona, E-08193 Bellaterra (Barcelona), Spain, Ll.M. MirLaboratorio de Fisica de Altas Energías, Universidad Autonoma de Barcelona, E-08193 Bellaterra (Barcelona), Spain, A. PachecoLaboratorio de Fisica de Altas Energías, Universidad Autonoma de Barcelona, E-08193 Bellaterra (Barcelona), Spain, M.G. CatanesiINFN Sezione di Bari e Dipartimento di Fisica dell’ Università, 1-70126 Bari, Italy, D. CreanzaINFN Sezione di Bari e Dipartimento di Fisica dell’ Università, 1-70126 Bari, Italy, M. de PalmaINFN Sezione di Bari e Dipartimento di Fisica dell’ Università, 1-70126 Bari, Italy, A. FarillaINFN Sezione di Bari e Dipartimento di Fisica dell’ Università, 1-70126 Bari, Italy, G. IaselliINFN Sezione di Bari e Dipartimento di Fisica dell’ Università, 1-70126 Bari, Italy, G. MaggiINFN Sezione di Bari e Dipartimento di Fisica dell’ Università, 1-70126 Bari, Italy, M. MaggiINFN Sezione di Bari e Dipartimento di Fisica dell’ Università, 1-70126 Bari, Italy, S. NataliINFN Sezione di Bari e Dipartimento di Fisica dell’ Università, 1-70126 Bari, Italy, S. NuzzoINFN Sezione di Bari e Dipartimento di Fisica dell’ Università, 1-70126 Bari, Italy, M. QuattrominiINFN Sezione di Bari e Dipartimento di Fisica dell’ Università, 1-70126 Bari, Italy, A. RanieriINFN Sezione di Bari e Dipartimento di Fisica dell’ Università, 1-70126 Bari, Italy, G. RasoINFN Sezione di Bari e Dipartimento di Fisica dell’ Università, 1-70126 Bari, Italy, F. RomanoINFN Sezione di Bari e Dipartimento di Fisica dell’ Università, 1-70126 Bari, Italy, F. RuggieriINFN Sezione di Bari e Dipartimento di Fisica dell’ Università, 1-70126 Bari, Italy, G. SelvaggiINFN Sezione di Bari e Dipartimento di Fisica dell’ Università, 1-70126 Bari, Italy, L. SilvestrisINFN Sezione di Bari e Dipartimento di Fisica dell’ Università, 1-70126 Bari, Italy, P. TempestaINFN Sezione di Bari e Dipartimento di Fisica dell’ Università, 1-70126 Bari, Italy, G. ZitoINFN Sezione di Bari e Dipartimento di Fisica dell’ Università, 1-70126 Bari, Italy, Y. GaoInstitute of High-Energy Physics, Academia Sinica. Beijing, People’s Republic of China, H. HuInstitute of High-Energy Physics, Academia Sinica. Beijing, People’s Republic of China, D. HuangInstitute of High-Energy Physics, Academia Sinica. Beijing, People’s Republic of China, X. HuangInstitute of High-Energy Physics, Academia Sinica. Beijing, People’s Republic of China, J. LinInstitute of High-Energy Physics, Academia Sinica. Beijing, People’s Republic of China, J. LouInstitute of High-Energy Physics, Academia Sinica. Beijing, People’s Republic of China, C. QiaoInstitute of High-Energy Physics, Academia Sinica. Beijing, People’s Republic of China, T. RuanInstitute of High-Energy Physics, Academia Sinica. Beijing, People’s Republic of China, T. WangInstitute of High-Energy Physics, Academia Sinica. Beijing, People’s Republic of China, Y. XieInstitute of High-Energy Physics, Academia Sinica. Beijing, People’s Republic of China, D. XuInstitute of High-Energy Physics, Academia Sinica. Beijing, People’s Republic of China, R. XuInstitute of High-Energy Physics, Academia Sinica. Beijing, People’s Republic of China, J. ZhangInstitute of High-Energy Physics, Academia Sinica. Beijing, People’s Republic of China, W. ZhaoInstitute of High-Energy Physics, Academia Sinica. Beijing, People’s Republic of China, W.B. AtwoodEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, L.A.T. BauerdickEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, F. BirdEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, E. BlucherEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, G. BonviciniEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, F. BossiEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, J. BoudreauEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, D. BrownEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, T.H. BurnettEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, H. DrevermannEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, R.W. FortyEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, C. GrabEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, R. HagelbergEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, S. HaywoodEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, J. HilgartEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, B. JostEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, M. KasemannEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, J. KnoblochEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, A. LacourtEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, E. LançonEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, I. LehrausEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, T. LohseEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, A. LusianiEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, A. MarchioroEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, M. MartinezEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, P. MatoEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, S. MenaryEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, A. MintenEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, A. MiottoEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, R. MiquelEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, H.-G. MoserEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, J. NashEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, P. PalazziEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, F. RanjardEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, G. RedlingerEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, A. RothEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, J. RothbergEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, H. RotscheidtEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, M. SaichEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, R.St. DenisEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, D. SchlatterEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, M. TakashimaEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, M. TalbyEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, W. TejessyEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, H. WachsmuthEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, S. WasserbaechEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, S. WheelerEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, W. WiedenmannEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, W. WitzelingEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, J. WotschackEuropean Laboratory for Particle Physics (CERN), CH-1211 Geneva 23, Switzerland, Z. AjaltouniLaboratoire de Physique Corpusculaire, Université Blaise Pascal, IN2P3-CNRS, Clermont-Ferrand, F-63177 Aubière, France, M. Bardadin-OtwinowskaLaboratoire de Physique Corpusculaire, Université Blaise Pascal, IN2P3-CNRS, Clermont-Ferrand, F-63177 Aubière, France, R. El FellousLaboratoire de Physique Corpusculaire, Université Blaise Pascal, IN2P3-CNRS, Clermont-Ferrand, F-63177 Aubière, France, A. FalvardLaboratoire de Physique Corpusculaire, Université Blaise Pascal, IN2P3-CNRS, Clermont-Ferrand, F-63177 Aubière, France, P. GayLaboratoire de Physique Corpusculaire, Université Blaise Pascal, IN2P3-CNRS, Clermont-Ferrand, F-63177 Aubière, France, J. HarveyLaboratoire de Physique Corpusculaire, Université Blaise Pascal, IN2P3-CNRS, Clermont-Ferrand, F-63177 Aubière, France, P. HenrardLaboratoire de Physique Corpusculaire, Université Blaise Pascal, IN2P3-CNRS, Clermont-Ferrand, F-63177 Aubière, France, J. JoussetLaboratoire de Physique Corpusculaire, Université Blaise Pascal, IN2P3-CNRS, Clermont-Ferrand, F-63177 Aubière, France, B. MichelLaboratoire de Physique Corpusculaire, Université Blaise Pascal, IN2P3-CNRS, Clermont-Ferrand, F-63177 Aubière, France, J.-C. MontretLaboratoire de Physique Corpusculaire, Université Blaise Pascal, IN2P3-CNRS, Clermont-Ferrand, F-63177 Aubière, France, D. PallinLaboratoire de Physique Corpusculaire, Université Blaise Pascal, IN2P3-CNRS, Clermont-Ferrand, F-63177 Aubière, France, P. PerretLaboratoire de Physique Corpusculaire, Université Blaise Pascal, IN2P3-CNRS, Clermont-Ferrand, F-63177 Aubière, France, J. ProriolLaboratoire de Physique Corpusculaire, Université Blaise Pascal, IN2P3-CNRS, Clermont-Ferrand, F-63177 Aubière, France, F. PrulhièreLaboratoire de Physique Corpusculaire, Université Blaise Pascal, IN2P3-CNRS, Clermont-Ferrand, F-63177 Aubière, France, G. StimpflLaboratoire de Physique Corpusculaire, Université Blaise Pascal, IN2P3-CNRS, Clermont-Ferrand, F-63177 Aubière, France, J.D. HansenNiels Bohr Institute, DK-2100 Copenhagen, Denmark, J.R. HansenNiels Bohr Institute, DK-2100 Copenhagen, Denmark, P.H. HansenNiels Bohr Institute, DK-2100 Copenhagen, Denmark, R. MøllerudNiels Bohr Institute, DK-2100 Copenhagen, Denmark, B.S. NilssonNiels Bohr Institute, DK-2100 Copenhagen, Denmark, I. EfthymiopoulosNuclear Research Center Demokritos (NRCD), Athens, Greece, E. SimopoulouNuclear Research Center Demokritos (NRCD), Athens, Greece, A. VayakiNuclear Research Center Demokritos (NRCD), Athens, Greece, J. BadierLaboratoire de Physique Nucléaire et des Hautes Energies, Ecole Polytechnique, IN2P3-CNRS, F-91128 Palaiseau Cedex, France, A. BlondelLaboratoire de Physique Nucléaire et des Hautes Energies, Ecole Polytechnique, IN2P3-CNRS, F-91128 Palaiseau Cedex, France, G. BonneaudLaboratoire de Physique Nucléaire et des Hautes Energies, Ecole Polytechnique, IN2P3-CNRS, F-91128 Palaiseau Cedex, France, J. BourotteLaboratoire de Physique Nucléaire et des Hautes Energies, Ecole Polytechnique, IN2P3-CNRS, F-91128 Palaiseau Cedex, France, F. BraemsLaboratoire de Physique Nucléaire et des Hautes Energies, Ecole Polytechnique, IN2P3-CNRS, F-91128 Palaiseau Cedex, France, J.C. BrientLaboratoire de Physique Nucléaire et des Hautes Energies, Ecole Polytechnique, IN2P3-CNRS, F-91128 Palaiseau Cedex, France, G. FouqueLaboratoire de Physique Nucléaire et des Hautes Energies, Ecole Polytechnique, IN2P3-CNRS, F-91128 Palaiseau Cedex, France, A. GamessLaboratoire de Physique Nucléaire et des Hautes Energies, Ecole Polytechnique, IN2P3-CNRS, F-91128 Palaiseau Cedex, France, R. GuirletLaboratoire de Physique Nucléaire et des Hautes Energies, Ecole Polytechnique, IN2P3-CNRS, F-91128 Palaiseau Cedex, France, S. OrteuLaboratoire de Physique Nucléaire et des Hautes Energies, Ecole Polytechnique, IN2P3-CNRS, F-91128 Palaiseau Cedex, France, A. RosowskyLaboratoire de Physique Nucléaire et des Hautes Energies, Ecole Polytechnique, IN2P3-CNRS, F-91128 Palaiseau Cedex, France, A. RougéLaboratoire de Physique Nucléaire et des Hautes Energies, Ecole Polytechnique, IN2P3-CNRS, F-91128 Palaiseau Cedex, France, M. RumpfLaboratoire de Physique Nucléaire et des Hautes Energies, Ecole Polytechnique, IN2P3-CNRS, F-91128 Palaiseau Cedex, France, R. TanakaLaboratoire de Physique Nucléaire et des Hautes Energies, Ecole Polytechnique, IN2P3-CNRS, F-91128 Palaiseau Cedex, France, H. VideauLaboratoire de Physique Nucléaire et des Hautes Energies, Ecole Polytechnique, IN2P3-CNRS, F-91128 Palaiseau Cedex, France, D.J. CandlinDepartment of Physics, University of Edinburgh, Edinburgh EH93JZ, UK, E. VeitchDepartment of Physics, University of Edinburgh, Edinburgh EH93JZ, UK, G. ParriniDipartimento di Fisica, Università di Firenze, INFN Sezione di Firenze, 1-50125 Firenze, Italy, M. CordenSupercomputer Computations Research Institute and Department of Physics, Florida State University, Tallahassee, FL 32306, USA, C. GeorgiopoulosSupercomputer Computations Research Institute and Department of Physics, Florida State University, Tallahassee, FL 32306, USA, M. IkedaSupercomputer Computations Research Institute and Department of Physics, Florida State University, Tallahassee, FL 32306, USA, J. LannuttiSupercomputer Computations Research Institute and Department of Physics, Florida State University, Tallahassee, FL 32306, USA, D. LevinthalSupercomputer Computations Research Institute and Department of Physics, Florida State University, Tallahassee, FL 32306, USA, M. MermikidesSupercomputer Computations Research Institute and Department of Physics, Florida State University, Tallahassee, FL 32306, USA, L. SawyerSupercomputer Computations Research Institute and Department of Physics, Florida State University, Tallahassee, FL 32306, USA, A. AntonelliLaboratori Nazionali dell’INFN (LNF-INFN), 1-00044 Frascati, Italy, R. BaldiniLaboratori Nazionali dell’INFN (LNF-INFN), 1-00044 Frascati, Italy, G. BencivenniLaboratori Nazionali dell’INFN (LNF-INFN), 1-00044 Frascati, Italy, G. BolognaLaboratori Nazionali dell’INFN (LNF-INFN), 1-00044 Frascati, Italy, P. CampanaLaboratori Nazionali dell’INFN (LNF-INFN), 1-00044 Frascati, Italy, G. CaponLaboratori Nazionali dell’INFN (LNF-INFN), 1-00044 Frascati, Italy, F. CeruttiLaboratori Nazionali dell’INFN (LNF-INFN), 1-00044 Frascati, Italy, V. ChiarellaLaboratori Nazionali dell’INFN (LNF-INFN), 1-00044 Frascati, Italy, B. D’Ettorre-PiazzoliLaboratori Nazionali dell’INFN (LNF-INFN), 1-00044 Frascati, Italy, G. FeliciLaboratori Nazionali dell’INFN (LNF-INFN), 1-00044 Frascati, Italy, P. LaurelliLaboratori Nazionali dell’INFN (LNF-INFN), 1-00044 Frascati, Italy, G. MannocchiLaboratori Nazionali dell’INFN (LNF-INFN), 1-00044 Frascati, Italy, F. MurtasLaboratori Nazionali dell’INFN (LNF-INFN), 1-00044 Frascati, Italy, G.P. MurtasLaboratori Nazionali dell’INFN (LNF-INFN), 1-00044 Frascati, Italy, G. NicolettiLaboratori Nazionali dell’INFN (LNF-INFN), 1-00044 Frascati, Italy, L. PassalacquaLaboratori Nazionali dell’INFN (LNF-INFN), 1-00044 Frascati, Italy, M. Pepe-AltarelliLaboratori Nazionali dell’INFN (LNF-INFN), 1-00044 Frascati, Italy, P. PicchiLaboratori Nazionali dell’INFN (LNF-INFN), 1-00044 Frascati, Italy, P. ZografouLaboratori Nazionali dell’INFN (LNF-INFN), 1-00044 Frascati, Italy, B. AltoonDepartment of Physics and Astronomy, University of Glasgow, Glasgow G128QQ, UK, O. BoyleDepartment of Physics and Astronomy, University of Glasgow, Glasgow G128QQ, UK, A.W. HalleyDepartment of Physics and Astronomy, University of Glasgow, Glasgow G128QQ, UK, I. ten HaveDepartment of Physics and Astronomy, University of Glasgow, Glasgow G128QQ, UK, J.L. HearnsDepartment of Physics and Astronomy, University of Glasgow, Glasgow G128QQ, UK, J.G. LynchDepartment of Physics and Astronomy, University of Glasgow, Glasgow G128QQ, UK, W.T. MortonDepartment of Physics and Astronomy, University of Glasgow, Glasgow G128QQ, UK, C. RaineDepartment of Physics and Astronomy, University of Glasgow, Glasgow G128QQ, UK, J.M. ScarrDepartment of Physics and Astronomy, University of Glasgow, Glasgow G128QQ, UK, K. SmithDepartment of Physics and Astronomy, University of Glasgow, Glasgow G128QQ, UK, A.S. ThompsonDepartment of Physics and Astronomy, University of Glasgow, Glasgow G128QQ, UK, R.M. TurnbullDepartment of Physics and Astronomy, University of Glasgow, Glasgow G128QQ, UK, B. BrandlInstitut für Hochenergiephysik, Universität Heidelberg, W-6900 Heidelberg, Federal Republic of Germany, O. BraunInstitut für Hochenergiephysik, Universität Heidelberg, W-6900 Heidelberg, Federal Republic of Germany, R. GeigesInstitut für Hochenergiephysik, Universität Heidelberg, W-6900 Heidelberg, Federal Republic of Germany, C. GewenigerInstitut für Hochenergiephysik, Universität Heidelberg, W-6900 Heidelberg, Federal Republic of Germany, P. HankeInstitut für Hochenergiephysik, Universität Heidelberg, W-6900 Heidelberg, Federal Republic of Germany, V. HeppInstitut für Hochenergiephysik, Universität Heidelberg, W-6900 Heidelberg, Federal Republic of Germany, E.E. KlugeInstitut für Hochenergiephysik, Universität Heidelberg, W-6900 Heidelberg, Federal Republic of Germany, Y. MaumaryInstitut für Hochenergiephysik, Universität Heidelberg, W-6900 Heidelberg, Federal Republic of Germany, A. PutzerInstitut für Hochenergiephysik, Universität Heidelberg, W-6900 Heidelberg, Federal Republic of Germany, B. RenschInstitut für Hochenergiephysik, Universität Heidelberg, W-6900 Heidelberg, Federal Republic of Germany, A. StahlInstitut für Hochenergiephysik, Universität Heidelberg, W-6900 Heidelberg, Federal Republic of Germany, K. TittelInstitut für Hochenergiephysik, Universität Heidelberg, W-6900 Heidelberg, Federal Republic of Germany, M. WunschInstitut für Hochenergiephysik, Universität Heidelberg, W-6900 Heidelberg, Federal Republic of Germany, A.T. BelkDepartment of Physics, Imperial College, London SW72BZ, UK, R. BeuselinckDepartment of Physics, Imperial College, London SW72BZ, UK, D.M. BinnieDepartment of Physics, Imperial College, London SW72BZ, UK, W. CameronDepartment of Physics, Imperial College, London SW72BZ, UK, M. CattaneoDepartment of Physics, Imperial College, London SW72BZ, UK, P.J. DornanDepartment of Physics, Imperial College, London SW72BZ, UK, S. DugeayDepartment of Physics, Imperial College, London SW72BZ, UK, A.M. GreeneDepartment of Physics, Imperial College, London SW72BZ, UK, J.F. HassardDepartment of Physics, Imperial College, London SW72BZ, UK, N.M. LieskeDepartment of Physics, Imperial College, London SW72BZ, UK, S.J. PattonDepartment of Physics, Imperial College, London SW72BZ, UK, D.G. PayneDepartment of Physics, Imperial College, London SW72BZ, UK, M.J. PhillipsDepartment of Physics, Imperial College, London SW72BZ, UK, J.K. SedgbeerDepartment of Physics, Imperial College, London SW72BZ, UK, G. TaylorDepartment of Physics, Imperial College, London SW72BZ, UK, I.R. TomalinDepartment of Physics, Imperial College, London SW72BZ, UK, A. G. WrightDepartment of Physics, Imperial College, London SW72BZ, UK, P. GirtlerInstitut für Experimentalphysik, Universität Innsbruck, A-6020 Innbruck, Austria, D. KuhnInstitut für Experimentalphysik, Universität Innsbruck, A-6020 Innbruck, Austria, G. RudolphInstitut für Experimentalphysik, Universität Innsbruck, A-6020 Innbruck, Austria, C.K. BowderyDepartment of Physics, University of Lancaster, Lancaster LA14YB, UK, T.J. BrodbeckDepartment of Physics, University of Lancaster, Lancaster LA14YB, UK, A.J. FinchDepartment of Physics, University of Lancaster, Lancaster LA14YB, UK, F. FosterDepartment of Physics, University of Lancaster, Lancaster LA14YB, UK, G. HughesDepartment of Physics, University of Lancaster, Lancaster LA14YB, UK, N.R. KeemerDepartment of Physics, University of Lancaster, Lancaster LA14YB, UK, M. NuttallDepartment of Physics, University of Lancaster, Lancaster LA14YB, UK, A. PatelDepartment of Physics, University of Lancaster, Lancaster LA14YB, UK, B.S. RowlingsonDepartment of Physics, University of Lancaster, Lancaster LA14YB, UK, T. SloanDepartment of Physics, University of Lancaster, Lancaster LA14YB, UK, S.W. SnowDepartment of Physics, University of Lancaster, Lancaster LA14YB, UK, E.P. WhelanDepartment of Physics, University of Lancaster, Lancaster LA14YB, UK, T. BarczewskiInstitut für Physik, Universität Mainz, W-6500 Mainz, Federal Republic of Germany, K. KleinknechtInstitut für Physik, Universität Mainz, W-6500 Mainz, Federal Republic of Germany, J. RaabInstitut für Physik, Universität Mainz, W-6500 Mainz, Federal Republic of Germany, B. RenkInstitut für Physik, Universität Mainz, W-6500 Mainz, Federal Republic of Germany, S. RoehnInstitut für Physik, Universität Mainz, W-6500 Mainz, Federal Republic of Germany, H.-G. SanderInstitut für Physik, Universität Mainz, W-6500 Mainz, Federal Republic of Germany, M. SchmellingInstitut für Physik, Universität Mainz, W-6500 Mainz, Federal Republic of Germany, H. SchmidtInstitut für Physik, Universität Mainz, W-6500 Mainz, Federal Republic of Germany, F. SteegInstitut für Physik, Universität Mainz, W-6500 Mainz, Federal Republic of Germany, S.M. WaltherInstitut für Physik, Universität Mainz, W-6500 Mainz, Federal Republic of Germany, B. WolfInstitut für Physik, Universität Mainz, W-6500 Mainz, Federal Republic of Germany, J-P. AlbaneseCentre de Physique des Particules, Faculté des Sciences de Luminy, IN2P3-CNRS, F-13288 Marseille, France, J-J. AubertCentre de Physique des Particules, Faculté des Sciences de Luminy, IN2P3-CNRS, F-13288 Marseille, France, C. BenchoukCentre de Physique des Particules, Faculté des Sciences de Luminy, IN2P3-CNRS, F-13288 Marseille, France, V. BernardCentre de Physique des Particules, Faculté des Sciences de Luminy, IN2P3-CNRS, F-13288 Marseille, France, A. BonissentCentre de Physique des Particules, Faculté des Sciences de Luminy, IN2P3-CNRS, F-13288 Marseille, France, D. CourvoisierCentre de Physique des Particules, Faculté des Sciences de Luminy, IN2P3-CNRS, F-13288 Marseille, France, F. EtienneCentre de Physique des Particules, Faculté des Sciences de Luminy, IN2P3-CNRS, F-13288 Marseille, France, S. PapalexiouCentre de Physique des Particules, Faculté des Sciences de Luminy, IN2P3-CNRS, F-13288 Marseille, France, P. PayreCentre de Physique des Particules, Faculté des Sciences de Luminy, IN2P3-CNRS, F-13288 Marseille, France, B. PietrzykCentre de Physique des Particules, Faculté des Sciences de Luminy, IN2P3-CNRS, F-13288 Marseille, France, Z. QianCentre de Physique des Particules, Faculté des Sciences de Luminy, IN2P3-CNRS, F-13288 Marseille, France, H. BeckerMax-Planck-Institut für Physik und Astrophysik, Werner-Heisenberg-Institut für Physik, W-8000 München, Federal Republic of Germany, W. BlumMax-Planck-Institut für Physik und Astrophysik, Werner-Heisenberg-Institut für Physik, W-8000 München, Federal Republic of Germany, P. CattaneoMax-Planck-Institut für Physik und Astrophysik, Werner-Heisenberg-Institut für Physik, W-8000 München, Federal Republic of Germany, G. CowanMax-Planck-Institut für Physik und Astrophysik, Werner-Heisenberg-Institut für Physik, W-8000 München, Federal Republic of Germany, B. DehningMax-Planck-Institut für Physik und Astrophysik, Werner-Heisenberg-Institut für Physik, W-8000 München, Federal Republic of Germany, H. DietlMax-Planck-Institut für Physik und Astrophysik, Werner-Heisenberg-Institut für Physik, W-8000 München, Federal Republic of Germany, F. DydakMax-Planck-Institut für Physik und Astrophysik, Werner-Heisenberg-Institut für Physik, W-8000 München, Federal Republic of Germany, M. Fernandez-BosmanMax-Planck-Institut für Physik und Astrophysik, Werner-Heisenberg-Institut für Physik, W-8000 München, Federal Republic of Germany, T. Hansl-KozaneckaMax-Planck-Institut für Physik und Astrophysik, Werner-Heisenberg-Institut für Physik, W-8000 München, Federal Republic of Germany, A. JahnMax-Planck-Institut für Physik und Astrophysik, Werner-Heisenberg-Institut für Physik, W-8000 München, Federal Republic of Germany, W. KozaneckiMax-Planck-Institut für Physik und Astrophysik, Werner-Heisenberg-Institut für Physik, W-8000 München, Federal Republic of Germany, E. LangeMax-Planck-Institut für Physik und Astrophysik, Werner-Heisenberg-Institut für Physik, W-8000 München, Federal Republic of Germany, J. LauberMax-Planck-Institut für Physik und Astrophysik, Werner-Heisenberg-Institut für Physik, W-8000 München, Federal Republic of Germany, G. LütjensMax-Planck-Institut für Physik und Astrophysik, Werner-Heisenberg-Institut für Physik, W-8000 München, Federal Republic of Germany, G. LutzMax-Planck-Institut für Physik und Astrophysik, Werner-Heisenberg-Institut für Physik, W-8000 München, Federal Republic of Germany, W. MännerMax-Planck-Institut für Physik und Astrophysik, Werner-Heisenberg-Institut für Physik, W-8000 München, Federal Republic of Germany, Y. PanMax-Planck-Institut für Physik und Astrophysik, Werner-Heisenberg-Institut für Physik, W-8000 München, Federal Republic of Germany, R. RichterMax-Planck-Institut für Physik und Astrophysik, Werner-Heisenberg-Institut für Physik, W-8000 München, Federal Republic of Germany, J. SchröderMax-Planck-Institut für Physik und Astrophysik, Werner-Heisenberg-Institut für Physik, W-8000 München, Federal Republic of Germany, A.S. SchwarzMax-Planck-Institut für Physik und Astrophysik, Werner-Heisenberg-Institut für Physik, W-8000 München, Federal Republic of Germany, R. SettlesMax-Planck-Institut für Physik und Astrophysik, Werner-Heisenberg-Institut für Physik, W-8000 München, Federal Republic of Germany, U. StierlinMax-Planck-Institut für Physik und Astrophysik, Werner-Heisenberg-Institut für Physik, W-8000 München, Federal Republic of Germany, J. ThomasMax-Planck-Institut für Physik und Astrophysik, Werner-Heisenberg-Institut für Physik, W-8000 München, Federal Republic of Germany, G. WolfMax-Planck-Institut für Physik und Astrophysik, Werner-Heisenberg-Institut für Physik, W-8000 München, Federal Republic of Germany, V. BertinLaboratoire de l’Accélérateur Linéaire, Université de Paris-Sud, INP-CNRS, F-91405 Orsay Cedex, France, J. BoucrotLaboratoire de l’Accélérateur Linéaire, Université de Paris-Sud, INP-CNRS, F-91405 Orsay Cedex, France, O. CallotLaboratoire de l’Accélérateur Linéaire, Université de Paris-Sud, INP-CNRS, F-91405 Orsay Cedex, France, X. ChenLaboratoire de l’Accélérateur Linéaire, Université de Paris-Sud, INP-CNRS, F-91405 Orsay Cedex, France, A. CordierLaboratoire de l’Accélérateur Linéaire, Université de Paris-Sud, INP-CNRS, F-91405 Orsay Cedex, France, M. DavierLaboratoire de l’Accélérateur Linéaire, Université de Paris-Sud, INP-CNRS, F-91405 Orsay Cedex, France, G. GanisLaboratoire de l’Accélérateur Linéaire, Université de Paris-Sud, INP-CNRS, F-91405 Orsay Cedex, France, J.-F. GrivazLaboratoire de l’Accélérateur Linéaire, Université de Paris-Sud, INP-CNRS, F-91405 Orsay Cedex, France, Ph. HeusseLaboratoire de l’Accélérateur Linéaire, Université de Paris-Sud, INP-CNRS, F-91405 Orsay Cedex, France, P. JanotLaboratoire de l’Accélérateur Linéaire, Université de Paris-Sud, INP-CNRS, F-91405 Orsay Cedex, France, D.W. KimLaboratoire de l’Accélérateur Linéaire, Université de Paris-Sud, INP-CNRS, F-91405 Orsay Cedex, France, F. Le DiberderLaboratoire de l’Accélérateur Linéaire, Université de Paris-Sud, INP-CNRS, F-91405 Orsay Cedex, France, J. LefrançoisLaboratoire de l’Accélérateur Linéaire, Université de Paris-Sud, INP-CNRS, F-91405 Orsay Cedex, France, A.-M. LutzLaboratoire de l’Accélérateur Linéaire, Université de Paris-Sud, INP-CNRS, F-91405 Orsay Cedex, France, J.-J. VeilletLaboratoire de l’Accélérateur Linéaire, Université de Paris-Sud, INP-CNRS, F-91405 Orsay Cedex, France, I. VideauLaboratoire de l’Accélérateur Linéaire, Université de Paris-Sud, INP-CNRS, F-91405 Orsay Cedex, France, Z. ZhangLaboratoire de l’Accélérateur Linéaire, Université de Paris-Sud, INP-CNRS, F-91405 Orsay Cedex, France, F. ZomerLaboratoire de l’Accélérateur Linéaire, Université de Paris-Sud, INP-CNRS, F-91405 Orsay Cedex, France, D. AbbaneoDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, S.R. AmendoliaDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, G. BagliesiDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, G. BatignaniDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, L. BosisioDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, U. BottigliDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, C. BradaschiaDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, M. CarpinelliDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, M.A. CiocciDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, R. Dell’OrsoDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, I. FerranteDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, F. FidecaroDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, L. FoàDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, E. FocardiDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, F. FortiDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, C. GattoDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, A. GiassiDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, M.A. GiorgiDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, F. LigabueDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, E.B. MannelliDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, P.S. MarrocchesiDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, A. MessineoDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, L. MonetaDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, F. PallaDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, G. SanguinettiDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, J. SteinbergerDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, R. TenchiniDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, G. TonelliDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, G. TriggianiDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, C. VanniniDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, A. VenturiDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, P.G. VerdiniDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, J. WalshDipartimento di Fisica dell’Università, INFN Sezione di Pisa, e Scuola Normale Superiore, 1-56010 Pisa, Italy, J.M. CarterDepartment of Physics, Royal Holloway and Bedford New College, University of London, Surrey TW20OEX, UK, M.G. GreenDepartment of Physics, Royal Holloway and Bedford New College, University of London, Surrey TW20OEX, UK, P.V. MarchDepartment of Physics, Royal Holloway and Bedford New College, University of London, Surrey TW20OEX, UK, T. MedcalfDepartment of Physics, Royal Holloway and Bedford New College, University of London, Surrey TW20OEX, UK, I.S. QuaziDepartment of Physics, Royal Holloway and Bedford New College, University of London, Surrey TW20OEX, UK, J.A. StrongDepartment of Physics, Royal Holloway and Bedford New College, University of London, Surrey TW20OEX, UK, R.M. ThomasDepartment of Physics, Royal Holloway and Bedford New College, University of London, Surrey TW20OEX, UK, L.R. WestDepartment of Physics, Royal Holloway and Bedford New College, University of London, Surrey TW20OEX, UK, T. WildishDepartment of Physics, Royal Holloway and Bedford New College, University of London, Surrey TW20OEX, UK, D.R. BotterillParticle Physics Department, Rutherford Appleton Laboratory, Chilton, Didcot, OXON 0X11 OQX, UK, R.W. ClifftParticle Physics Department, Rutherford Appleton Laboratory, Chilton, Didcot, OXON 0X11 OQX, UK, T.R. EdgecockParticle Physics Department, Rutherford Appleton Laboratory, Chilton, Didcot, OXON 0X11 OQX, UK, M. EdwardsParticle Physics Department, Rutherford Appleton Laboratory, Chilton, Didcot, OXON 0X11 OQX, UK, S.M. FisherParticle Physics Department, Rutherford Appleton Laboratory, Chilton, Didcot, OXON 0X11 OQX, UK, T.J. JonesParticle Physics Department, Rutherford Appleton Laboratory, Chilton, Didcot, OXON 0X11 OQX, UK, P.R. NortonParticle Physics Department, Rutherford Appleton Laboratory, Chilton, Didcot, OXON 0X11 OQX, UK, D.P. SalmonParticle Physics Department, Rutherford Appleton Laboratory, Chilton, Didcot, OXON 0X11 OQX, UK, J.C. ThompsonParticle Physics Department, Rutherford Appleton Laboratory, Chilton, Didcot, OXON 0X11 OQX, UK, B. Bloch-DevauxDépartement de Physique des Particules Elémentaires, CEN-Saclay, F-91191 Gif-sur-Yvette Cedex, France, P. ColasDépartement de Physique des Particules Elémentaires, CEN-Saclay, F-91191 Gif-sur-Yvette Cedex, France, C. KlopfensteinDépartement de Physique des Particules Elémentaires, CEN-Saclay, F-91191 Gif-sur-Yvette Cedex, France, E. LocciDépartement de Physique des Particules Elémentaires, CEN-Saclay, F-91191 Gif-sur-Yvette Cedex, France, S. LoucatosDépartement de Physique des Particules Elémentaires, CEN-Saclay, F-91191 Gif-sur-Yvette Cedex, France, E. MonnierDépartement de Physique des Particules Elémentaires, CEN-Saclay, F-91191 Gif-sur-Yvette Cedex, France, P. PerezDépartement de Physique des Particules Elémentaires, CEN-Saclay, F-91191 Gif-sur-Yvette Cedex, France, J.A. PerlasDépartement de Physique des Particules Elémentaires, CEN-Saclay, F-91191 Gif-sur-Yvette Cedex, France, F. PerrierDépartement de Physique des Particules Elémentaires, CEN-Saclay, F-91191 Gif-sur-Yvette Cedex, France, J. RanderDépartement de Physique des Particules Elémentaires, CEN-Saclay, F-91191 Gif-sur-Yvette Cedex, France, J.-F. RenardyDépartement de Physique des Particules Elémentaires, CEN-Saclay, F-91191 Gif-sur-Yvette Cedex, France, A. RoussarieDépartement de Physique des Particules Elémentaires, CEN-Saclay, F-91191 Gif-sur-Yvette Cedex, France, J.-P. SchullerDépartement de Physique des Particules Elémentaires, CEN-Saclay, F-91191 Gif-sur-Yvette Cedex, France, J. SchwindlingDépartement de Physique des Particules Elémentaires, CEN-Saclay, F-91191 Gif-sur-Yvette Cedex, France, B. VallageDépartement de Physique des Particules Elémentaires, CEN-Saclay, F-91191 Gif-sur-Yvette Cedex, France, J.G. AshmanDepartment of Physics, University of Sheffield, Sheffield S37RH, UK, C.N. BoothDepartment of Physics, University of Sheffield, Sheffield S37RH, UK, C. ButtarDepartment of Physics, University of Sheffield, Sheffield S37RH, UK, R. CarneyDepartment of Physics, University of Sheffield, Sheffield S37RH, UK, S. CartwrightDepartment of Physics, University of Sheffield, Sheffield S37RH, UK, F. CombleyDepartment of Physics, University of Sheffield, Sheffield S37RH, UK, M. DinsdaleDepartment of Physics, University of Sheffield, Sheffield S37RH, UK, M. DogruDepartment of Physics, University of Sheffield, Sheffield S37RH, UK, F. HatfieldDepartment of Physics, University of Sheffield, Sheffield S37RH, UK, J. MartinDepartment of Physics, University of Sheffield, Sheffield S37RH, UK, D. ParkerDepartment of Physics, University of Sheffield, Sheffield S37RH, UK, P. ReevesDepartment of Physics, University of Sheffield, Sheffield S37RH, UK, L.F. ThompsonDepartment of Physics, University of Sheffield, Sheffield S37RH, UK, E. BarberioFachbereich Physik, Universität Siegen, W-5900 Siegen, Federal Republic of Germany, S. BrandtFachbereich Physik, Universität Siegen, W-5900 Siegen, Federal Republic of Germany, H. BurkhardtFachbereich Physik, Universität Siegen, W-5900 Siegen, Federal Republic of Germany, C. GrupenFachbereich Physik, Universität Siegen, W-5900 Siegen, Federal Republic of Germany, H. MeinhardFachbereich Physik, Universität Siegen, W-5900 Siegen, Federal Republic of Germany, L. MirabitoFachbereich Physik, Universität Siegen, W-5900 Siegen, Federal Republic of Germany, U. SchäferFachbereich Physik, Universität Siegen, W-5900 Siegen, Federal Republic of Germany, H. SeywerdFachbereich Physik, Universität Siegen, W-5900 Siegen, Federal Republic of Germany, G. ApollinariDipartimento di Fisica, Université di Trieste e INFN Sezione di Trieste, 1-34127 Trieste, Italy, G. GianniniDipartimento di Fisica, Université di Trieste e INFN Sezione di Trieste, 1-34127 Trieste, Italy, B. GobboDipartimento di Fisica, Université di Trieste e INFN Sezione di Trieste, 1-34127 Trieste, Italy, F. LielloDipartimento di Fisica, Université di Trieste e INFN Sezione di Trieste, 1-34127 Trieste, Italy, F. RagusaDipartimento di Fisica, Université di Trieste e INFN Sezione di Trieste, 1-34127 Trieste, Italy, L. RolandiDipartimento di Fisica, Université di Trieste e INFN Sezione di Trieste, 1-34127 Trieste, Italy, U. StieglerDipartimento di Fisica, Université di Trieste e INFN Sezione di Trieste, 1-34127 Trieste, Italy, L. BellantoniDepartment of Physics, University of Wisconsin, Madison, WI53706, USA, X. ChenDepartment of Physics, University of Wisconsin, Madison, WI53706, USA, D. CinabroDepartment of Physics, University of Wisconsin, Madison, WI53706, USA, J.S. ConwayDepartment of Physics, University of Wisconsin, Madison, WI53706, USA, D.F. CowenDepartment of Physics, University of Wisconsin, Madison, WI53706, USA, Z. FengDepartment of Physics, University of Wisconsin, Madison, WI53706, USA, D.P.S. FergusonDepartment of Physics, University of Wisconsin, Madison, WI53706, USA, Y.S. GaoDepartment of Physics, University of Wisconsin, Madison, WI53706, USA, J. GrahlDepartment of Physics, University of Wisconsin, Madison, WI53706, USA, J.L. HartonDepartment of Physics, University of Wisconsin, Madison, WI53706, USA, J.E. JacobsenDepartment of Physics, University of Wisconsin, Madison, WI53706, USA, R.C. JaredDepartment of Physics, University of Wisconsin, Madison, WI53706, USA, R.P. JohnsonDepartment of Physics, University of Wisconsin, Madison, WI53706, USA, B.W. Le ClaireDepartment of Physics, University of Wisconsin, Madison, WI53706, USA, Y.B. PanDepartment of Physics, University of Wisconsin, Madison, WI53706, USA, J.R. PaterDepartment of Physics, University of Wisconsin, Madison, WI53706, USA, Y. SaadiDepartment of Physics, University of Wisconsin, Madison, WI53706, USA, V. SharmaDepartment of Physics, University of Wisconsin, Madison, WI53706, USA, Z.H. ShiDepartment of Physics, University of Wisconsin, Madison, WI53706, USA, Y.H. TangDepartment of Physics, University of Wisconsin, Madison, WI53706, USA, A.M. WalshDepartment of Physics, University of Wisconsin, Madison, WI53706, USA, J.A. WearDepartment of Physics, University of Wisconsin, Madison, WI53706, USA, F.V. WeberDepartment of Physics, University of Wisconsin, Madison, WI53706, USA, M.H. WhitneyDepartment of Physics, University of Wisconsin, Madison, WI53706, USA, Sau Lan WuDepartment of Physics, University of Wisconsin, Madison, WI53706, USA and G. ZobernigDepartment of Physics, University of Wisconsin, Madison, WI53706, USAhttps://doi.org/10.1142/9789811264436_0023Cited by:0 PreviousNext AboutSectionsPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack CitationsRecommend to Library ShareShare onFacebookTwitterLinked InRedditEmail Abstract: The properties of the Z resonance are measured on the basis of 190000 Z decays into fermion pairs collected with the ALEPH detector at LEP. Assuming lepton universality, Mz = (91.182 ± 0.009exp ± 0.020L: P) GeV, Γz=(2484 ± 17) MeV, σhad 0=(41.44±0.36) nb, and Γhad/Γℓℓ=21.00±0.20. The corresponding number of light neutrino species is 2.97 ±0.07. The forward-backward asymmetry in leptonic decays is used to determine the ratio of vector to axial-vector coupling constants of leptons: gV2(MZ2)/gA2(MZ2)=0.0072±0.0027. Combining these results with ALEPH results on quark charge and b b¯ asymmetries, and τ polarization, sin2θW(MZ2) =0.2312±0.0018. In the context of the Minimal Standard Model, limits are placed on the top-quark mass. Reprinted by permission from Springer Nature: ALEPH Collaboration (D. Decamp et al.), Z. Phys. C 53, 1–20 (1992). ©1992. FiguresReferencesRelatedDetails Memorial Volume for Jack SteinbergerMetrics History PDF download

Fireworks, the event-display program of CMS, was extended with an advanced geometry visualization package. ROOT's TGeo geometry is used as internal representation, shared among several geometry views. Each view is represented by a GUI list-tree widget, implemented as a flat vector to allow for fast searching, selection, and filtering by material type, node name, and shape type. Display of logical and physical volumes is supported. Color, transparency, and visibility flags can be modified for each node or for a selection of nodes. Further operations, like opening of a new view or changing of the root node, can be performed via a context menu. Node selection and graphical properties determined by the list-tree view can be visualized in any 3D graphics view of Fireworks. As each 3D view can display any number of geometry views, a user is free to combine different geometry-view selections within the same 3D view. Node-selection by proximity to a given point is possible. A visual clipping box can be set for each geometry view to limit geometry drawing into a specified region. Visualization of geometric overlaps, as detected by TGeo, is also supported. The geometry visualization package is used for detailed inspection and display of simulation geometry with or without the event data. It also serves as a tool for geometry debugging and inspection, facilitating development of geometries for CMS detector upgrades and for SLHC.

The CMS Data Analysis School is an official event organized by the CMS Collaboration to teach students and post-docs how to perform a physics analysis. The school is coordinated by the CMS schools committee and was first implemented at the LHC Physics Center at Fermilab in 2010. As part of the training, there are a number of "short" exercises on physics object reconstruction and identification, Monte Carlo simulation, and statistical analysis, which are followed by "long" exercises based on physics analyses. Some of the long exercises go beyond the current state of the art of the corresponding CMS analyses.

The CMS 2004 Data Challenge (DC04) was devised to test several key aspects of the CMS Computing Model in three ways: by trying to sustain a 25 Hz reconstruction rate at the Tier-0; by distributing the reconstructed data to six Tier-1 Regional Centres (CNAF in Italy, FNAL in US, GridKA in Germany, IN2P3 in France, PIC in Spain, RAL in UK) and handling catalogue issues; by granting data accessibility at remote centres for analysis. Simulated events, up to the digitization step, were produced prior to the DC as input for the reconstruction in the Pre-Challenge Production (PCP04). In this paper, the model of the Tier-0 implementation used in DC04 is described, as well as the experience gained in using the newly developed data distribution management layer, which allowed CMS to successfully direct the distribution of data from Tier-0 to Tier-1 sites by loosely integrating a number of available Grid components. While developing and testing this system, CMS explored the overall functionality and limits of each component, in any of the different implementations that were deployed within DC04. The role of Tier-1's is presented and discussed, from the import of reconstructed data from Tier-0, to the archiving on to the local Mass Storage System (MSS) and the data distribution management to Tier-2's for analysis. Participating Tier-1's differed in available resources, setup and configuration. A critical evaluation of the results and performances achieved adopting different strategies in the organization and management of each Tier-1 centre to support CMS DC04 is presented.

The CMS Integration Grid Testbed (IGT) comprises USCMS Tier-1 and Tier-2 hardware at the following sites: the California Institute of Technology, Fermi National Accelerator Laboratory, the University of California at San Diego, and the University of Florida at Gainesville. The IGT runs jobs using the Globus Toolkit with a DAGMan and Condor-G front end. The virtual organization (VO) is managed using VO management scripts from the European Data Grid (EDG). Gridwide monitoring is accomplished using local tools such as Ganglia interfaced into the Globus Metadata Directory Service (MDS) and the agent based Mona Lisa. Domain specific software is packaged and installed using the Distrib ution After Release (DAR) tool of CMS, while middleware under the auspices of the Virtual Data Toolkit (VDT) is distributed using Pacman. During a continuo us two month span in Fall of 2002, over 1 million official CMS GEANT based Monte Carlo events were generated and returned to CERN for analysis while being demonstrated at SC2002. In this paper, we describe the process that led to one of the world's first continuously available, functioning grids.

Computing plays an essential role in all aspects of high energy physics. As computational technology evolves rapidly in new directions, and data throughput and volume continue to follow a steep trend-line, it is important for the HEP community to develop an effective response to a series of expected challenges. In order to help shape the desired response, the HEP Forum for Computational Excellence (HEP-FCE) initiated a roadmap planning activity with two key overlapping drivers -- 1) software effectiveness, and 2) infrastructure and expertise advancement. The HEP-FCE formed three working groups, 1) Applications Software, 2) Software Libraries and Tools, and 3) Systems (including systems software), to provide an overview of the current status of HEP computing and to present findings and opportunities for the desired HEP computational roadmap. The final versions of the reports are combined in this document, and are presented along with introductory material.

This paper describes a programme to study the computing model in CMS after the next long shutdown near the end of the decade.

Computing plays an essential role in all aspects of high energy physics. As computational technology evolves rapidly in new directions, and data throughput and volume continue to follow a steep trend-line, it is important for the HEP community to develop an effective response to a series of expected challenges. In order to help shape the desired response, the HEP Forum for Computational Excellence (HEP-FCE) initiated a roadmap planning activity with two key overlapping drivers -- 1) software effectiveness, and 2) infrastructure and expertise advancement. The HEP-FCE formed three working groups, 1) Applications Software, 2) Software Libraries and Tools, and 3) Systems (including systems software), to provide an overview of the current status of HEP computing and to present findings and opportunities for the desired HEP computational roadmap. The final versions of the reports are combined in this document, and are presented along with introductory material.

The operation of the CMS computing system requires a complex monitoring system to cover all its aspects: central services, databases, the distributed computing infrastructure, production and analysis workflows, the global overview of the CMS computing activities and the related historical information. Several tools are available to provide this information, developed both inside and outside of the collaboration and often used in common with other experiments. Despite the fact that the current monitoring allowed CMS to successfully perform its computing operations, an evolution of the system is clearly required, to adapt to the recent changes in the data and workload management tools and models and to address some shortcomings that make its usage less than optimal. Therefore, a recent and ongoing coordinated effort was started in CMS, aiming at improving the entire monitoring system by identifying its weaknesses and the new requirements from the stakeholders, rationalise and streamline existing components and drive future software development. This contribution gives a complete overview of the CMS monitoring system and a description of all the recent activities that have been started with the goal of providing a more integrated, modern and functional global monitoring system for computing operations.

At the heart of experimental high energy physics (HEP) is the development of facilities and instrumentation that provide sensitivity to new phenomena. Our understanding of nature at its most fundamental level is advanced through the analysis and interpretation of data from sophisticated detectors in HEP experiments. The goal of data analysis systems is to realize the maximum possible scientific potential of the data within the constraints of computing and human resources in the least time. To achieve this goal, future analysis systems should empower physicists to access the data with a high level of interactivity, reproducibility and throughput capability. As part of the HEP Software Foundation Community White Paper process, a working group on Data Analysis and Interpretation was formed to assess the challenges and opportunities in HEP data analysis and develop a roadmap for activities in this area over the next decade. In this report, the key findings and recommendations of the Data Analysis and Interpretation Working Group are presented.

The CMS Integration Grid Testbed (IGT) comprises USCMS Tier-2 and Tier-2 hardware at the following sites: the California Institute of Technology, Fermi National Accelerator Laboratory, the University of California at San Diego, and the University of Florida at Gainesville. The IGT runs jobs using the Globus Toolkit with a DAGMan and Condor-G front end. The virtual organization (VO) is managed using VO management scripts from the European Data Grid (EDG). Gridwide monitoring is accompolished using local tools such as Ganglia interfaced into the Globus Metadata Directory Service (MDS) and the agent based Mona Lisa. Domain specific software is packaged and installed using the Distribution After Release (DAR) tool of CMS, while middleware under the auspices of the Virtual Data Toolkit (VDT) is distributed using Pacman. During a continuous two month span in Fall of 2002, over 1 million official CMS GEANT based Monte Carlo events were generated and returned to CERN for analysis while being demonstrated at SC2002. In thie paper, we describe the process that led to one of the world's first continuously available functioning grids.

The tracking performance of the ALEPH time projection chamber (TPC) has been studied using the data taken during the LEP (Large Electron-Positron Collider) running periods in 1989 and 1990. After careful correction of residual distortions and optimization of coordinate reconstruction algorithms, a single coordinate resolution of 173 mu m in the azimuthal and 740 mu m in the longitudinal direction is achieved. This results in a momentum resolution for the TPC alone of Delta p/p/sup 2/=0.0012 (GeV/c)/sup -1/. In combination with the ALEPH inner tracking chamber (ITC), a total momentum resolution of Delta p/p/sup 2/=0.0008 (GeV/c)/sup -1/, close to the design specifications, is reached.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>