"TITLE","AUTHORS","SUBJECT","SUBJECT_RELATED","DESCRIPTION","PUBLISHER","AVAILABILITY","RESEARCH_ORG","SPONSORING_ORG","PUBLICATION_COUNTRY","PUBLICATION_DATE","CONTRIBUTING_ORGS","LANGUAGE","RESOURCE_TYPE","TYPE_QUALIFIER","JOURNAL_ISSUE","JOURNAL_VOLUME","RELATION","COVERAGE","FORMAT","IDENTIFIER","REPORT_NUMBER","DOE_CONTRACT_NUMBER","OTHER_IDENTIFIER","DOI","RIGHTS","ENTRY_DATE","OSTI_IDENTIFIER","PURL_URL" "Study of the inclusive production of {phi}{sup 0} mesons and measurement of the branching ratio of the Z{sup 0} bosons into strange quarks pairs with the DELPHI detector at LEP; Etude de la production inclusive de mesons {phi}{sup 0} et mesure du rapport d`embranchement du boson Z{sup 0} en paires de quarks etranges aupres de l`experience DELPHI au LEP","Pages, P","66 PHYSICS; 44 INSTRUMENTATION, INCLUDING NUCLEAR AND PARTICLE DETECTORS; BRANCHING RATIO; INCLUSIVE INTERACTIONS; LEP STORAGE RINGS; STRANGEONIUM; CHERENKOV COUNTERS; CLUSTER MODEL; DIFFERENTIAL CROSS SECTIONS; ELECTRON-POSITRON INTERACTIONS; FRAGMENTATION; GAMMA RADIATION; GAS TRACK DETECTORS; JET MODEL; KAONS; MASS DISTRIBUTION; MUON DETECTION; PAIR PRODUCTION; PARTICLE IDENTIFICATION; PARTICLE TRACKS; PARTONS; PHOTOELECTRON COUNTING; PHOTONS; QUANTUM CHROMODYNAMICS; SHOWER COUNTERS; STANDARD MODEL; SU-2 GROUPS; SU-3 GROUPS; TIME PROJECTION CHAMBERS; U-1 GROUPS; VIRTUAL PARTICLES; Z NEUTRAL BOSONS","","The thesis work is relative to an analysis of data collected by the DELPHI detector at LET in 1992 and 1993, in order to study the inclusive production production of {phi}{sup 0} mesons, reconstructed according to the decay mode {phi}{sup 0} {yields} K{sup +}K{sup -}. The kaon identification, indispensable to do this reconstruction, was made by the Barrel RICH detector of DELPHI. This study was first done to test the {phi}{sup 0} production in the Lund string model, which is one of the models used to describe the production of hadrons in the e{sup +}e{sup -}processes. The experimental distribution of the differential cross section of the inclusive {phi}{sup 0} production was compared to the one predicted by the model and indicates that the model well reproduces the experimental data. The mean number of produced {phi}{sup 0} per hadronic event was found to be: 0.091 {+-} 0.013, in good agreement with the expected value: 0.091. Next, high momentum {phi}{sup 0} mesons were used for a measurement of the branching ratio of the Z{sup 0} bosons into strange quark pairs: {Gamma}{sub ss}-bar/{Gamma}{sub had}. Three {phi}{sup 0} mesons samples were selected, for which the purity in Z{sup 0}{yields} ss-bar events was greater than 60, 70 and 80 %. For each of these 3 samples, the obtained experimental values are respectively: 0.16 {+-} 0.04, 0.13{+-}0.04 et 0.12{+-}0.05. These values show relatively large uncertainties and indicate an agreement of at the most 2.6 standard deviations to the expected value: 0.22. (author). 63 refs.","","INIS; OSTI as DE98601200","Strasbourg-1 Univ., 67 (France). Centre de Recherches Nucleaires; Strasbourg-1 Univ., 67 (France)","","France","1996-05-07","","French;English","Thesis/Dissertation","","","","Other Information: DN: 63 refs.; TH: These (D. es Sc.).; PBD: 7 May 1996","","Medium: ED; Size: 287 p.","ON: DE98601200","CRN-96-19","","Other: ON: DE98601200; TRN: FR9703509065530","https://doi.org/","","2018-04-24","529233","https://www.osti.gov/etdeweb/servlets/purl/529233"