Precise values of theZ resonance cross sections and lepton pair forward-backward asymmetries are measured from a sample of 1.3 millionZ decays into hadrons and charged leptons taken with the ALEPH detector at LEP. A silicon-tungsten luminosity calorimeter was installed in ALEPH in 1992, permitting the determination of the absolute luminosity to a systematic precision of 0.15% (experimental) and 0.25% (theoretical). This is combined with a better understanding of the hadronic event selection and an improved tau pair selection. Including the ALEPH results of the past three years one obtains sgr h 0 =(41.60±0.16) nb, andR l =20.69±0.09. The corresponding number of light neutrino species isN v =2.983±0.034. The lepton pair forward-backward asymmetry is used to derive the ratio of vector to axial-vector couplings of leptons:g V 2 (M Z 2 )/g A 2 (M Z 2 )=0.0058 ±0.0011. An application of these results to constrain one model with extraZ bosons is presented.
Z production cross sections and lepton pair forward-backward asymmetries / D. Buskulic;D. Casper;I. Bonis;D. Decamp;P. Chez;C. Goy;J. -P. Lees;M. -N. Minard;P. Odier;B. Pietrzyk;F. Ariztizabal;P. Comas;J. M. Crespo;I. Efthymiopoulos;E. Fernandez;M. Fernandez-Bosman;V. Gaitan;Ll. Garrido;M. Martinez;T. Mattison;S. Orten;A. Pacheco;C. Padilla;A. Pascual;D. Creanza;M. Palma;A. Farilla;G. Iaselli;G. Maggi;N. Marinelli;S. Natali;S. Nuzzo;A. Ranieri;G. Raso;F. Romano;F. Ruggieri;G. Selvaggi;L. Silvestris;P. Tempesta;G. Zito;Y. Chai;D. Huang;X. Huang;J. Lin;T. Wang;Y. Xie;D. Xu;R. Xu;J. Zhang;L. Zhang;W. Zhao;E. Blucher;G. Bonvicini;J. Boudreau;H. Drevermann;R. W. Forty;G. Ganis;C. Gay;M. Girone;R. Hagelberg;J. Harvey;J. Hilgart;R. Jacobsen;B. Jost;J. Knobloch;I. Lehraus;M. Maggi;C. Markou;P. Mato;H. Meinhard;A. Minten;R. Miquel;K. Moffeit;P. Palazzi;J. R. Pater;J. A. Perlas;P. Perrodo;J. -F. Pusztaszeri;F. Ranjard;L. Rolandi;J. Rothberg;T. Ruan;M. Saich;D. Schlatter;M. Schmelling;F. Sefkow;W. Tejessy;I. R. Tomalin;R. Veenhof;H. Wachsmuth;S. Wasserbaech;W. Wiedenmann;T. Wildish;W. Witzeling;J. Wotschack;Z. Ajaltouni;M. Bardadin-Otwinowska;A. Barres;C. Boyer;A. Falvard;P. Gay;C. Guicheney;P. Henrard;J. Jousset;B. Michel;J. -C. Montret;D. Pallin;P. Perret;F. Podlyski;J. Proriol;F. Saadi;T. Fearnley;J. B. Hansen;J. D. Hansen;J. R. Hansen;P. H. Hansen;S. D. Johnson;R. Møllerud;B. S. Nilsson;A. Kyriakis;E. Simopoulou;I. Siotis;A. Vayaki;K. Zachariadou;J. Badier;A. Blondel;G. Bonneaud;J. C. Brient;P. Bourdon;G. Fouque;L. Passalacqua;A. Rougé;M. Rumpf;R. Tanaka;M. Verderi;H. Videau;D. J. Candlin;M. I. Parsons;E. Veitch;E. Focardi;L. Moneta;G. Parrini;M. Corden;M. Delfino;C. Georgiopoulos;D. E. Jaffe;D. Levinthal;A. Antonelli;G. Bencivenni;G. Bologna;F. Bossi;P. Campana;G. Capon;F. Cerutti;V. Chiarella;G. Felici;P. Laurelli;G. Mannocchi;F. Murtas;G. P. Murtas;M. Pepe-Altarelli;S. Salomone;P. Colrain;I. Have;I. G. Knowles;J. G. Lynch;W. Maitland;W. T. Morton;C. Raine;P. Reeves;J. M. Scarr;K. Smith;M. G. Smith;A. S. Thompson;S. Thorn;R. M. Turnbull;U. Becker;O. Braun;C. Geweniger;P. Hanke;V. Hepp;E. E. Kluge;A. Putzer;B. Rensch;M. Schmidt;H. Stenzel;K. Tittel;M. Wunsch;R. Beuselinck;D. M. Binnie;W. Cameron;M. Cattaneo;D. J. Colling;P. J. Dornan;J. F. Hassard;N. Konstantinidis;A. Moutoussi;J. Nash;D. G. Payne;G. San Martin;J. K. Sedgbeer;A. G. Wright;P. Girtler;D. Kuhn;G. Rudolph;R. Vogl;C. K. Bowdery;T. J. Brodbeck;A. J. Finch;F. Foster;G. Hughes;D. Jackson;N. R. Keemer;M. Nuttall;A. Patel;T. Sloan;S. W. Snow;E. P. Whelan;A. Galla;A. M. Greene;K. Kleinknecht;J. Raab;B. Renk;H. -G. Sander;H. Schmidt;S. M. Walther;R. Wanke;B. Wolf;A. M. Bencheikh;C. Benchouk;A. Bonissent;D. Calvet;J. Carr;P. Coyle;C. Diaconu;F. Etienne;D. Nicod;P. Payre;L. Roos;D. Rousseau;P. Schwemling;M. Talby;S. Adlung;R. Assmann;C. Bauer;W. Blum;D. Brown;P. Cattaneo;B. Dehning;H. Dietl;F. Dydak;M. Frank;A. W. Halley;K. Jakobs;J. Lauber;G. Lütjens;G. Lutz;W. Männer;H. -G. Moser;R. Richter;J. Schröder;A. S. Schwarz;R. Settles;H. Seywerd;U. Stierlin;U. Stiegler;R. St. Denis;G. Wolf;R. Alemany;J. Boucrot;O. Callot;A. Cordier;M. Davier;L. Duflot;J. -F. Grivaz;Ph. Heusse;P. Janot;D. W. Kim;F. Diberder;J. Lefrançois;A. -M. Lutz;G. Musolino;M. -H. Schune;J. -J. Veillet;I. Videau;D. Abbaneo;G. Bagliesi;G. Batignani;U. Bottigli;C. Bozzi;G. Calderini;M. Carpinelli;M. A. Ciocci;V. Ciulli;R. Dell'Orso;I. Ferrante;F. Fidecaro;L. Foa;F. Forti;A. Giassi;M. A. Giorgi;A. Gregorio;F. Ligabue;A. Lusiani;P. S. Marrocchesi;E. B. Martin;A. Messineo;F. Palla;G. Rizzo;G. Sanguinetti;P. Spagnolo;J. Steinberger;R. Tenchini;G. Tonelli;G. Triggiani;A. Valassi;C. Vannini;A. Venturi;P. G. Verdini;J. Walsh;A. P. Betteridge;M. G. Green;D. L. Johnson;P. V. March;T. Medcalf;Ll. M. Mir;I. S. Quazi;J. A. Strong;V. Bertin;D. R. Botterill;R. W. Clifft;T. R. Edgecock;S. Haywood;M. Edwards;P. R. Norton;J. C. Thompson;B. Bloch-Devaux;P. Colas;H. Duarte;S. Emery;W. Kozanecki;E. Lançon;M. C. Lemaire;E. Locci;B. Marx;P. Perez;J. Rander;J. -F. Renardy;A. Rosowsky;A. Roussarie;J. -P. Schuller;J. Schwindling;D. Mohand;B. Vallage;R. P. Johnson;A. M. Litke;G. Taylor;J. Wear;W. Babbage;E. Beddall;C. N. Booth;S. Cartwright;F. Combley;I. Dawson;C. Rankin;L. F. Thompson;A. Böhrer;S. Brandt;G. Cowan;E. Feigl;C. Grupen;G. Lutters;J. Minguet-Rodriguez;F. Rivera;P. Saraiva;U. Schäfer;L. Smolik;L. Bosisio;R. Della Marina;G. Giannini;B. Gobbo;L. Pitis;F. Ragusa;L. Bellantoni;W. Chen;J. S. Conway;Z. Feng;D. P. S. Ferguson;Y. S. Gao;J. Grahl;J. L. Harton;O. J. Hayes;H. Hu;J. M. Nachtman;Y. B. Pan;Y. Saadi;M. Schmitt;I. Scott;V. Sharma;J. D. Turk;A. M. Walsh;F. V. Weber;Sau Lan Wu;X. Wu;M. Zheng;J. M. Yamartino;G. Zobernig. - In: ZEITSCHRIFT FÜR PHYSIK. C, PARTICLES AND FIELDS. - ISSN 0170-9739. - ELETTRONICO. - 62:(1994), pp. 539-550. [10.1007/BF01574159]
Z production cross sections and lepton pair forward-backward asymmetries
FOCARDI, ETTORE;CIULLI, VITALIANO;
1994
Abstract
Precise values of theZ resonance cross sections and lepton pair forward-backward asymmetries are measured from a sample of 1.3 millionZ decays into hadrons and charged leptons taken with the ALEPH detector at LEP. A silicon-tungsten luminosity calorimeter was installed in ALEPH in 1992, permitting the determination of the absolute luminosity to a systematic precision of 0.15% (experimental) and 0.25% (theoretical). This is combined with a better understanding of the hadronic event selection and an improved tau pair selection. Including the ALEPH results of the past three years one obtains sgr h 0 =(41.60±0.16) nb, andR l =20.69±0.09. The corresponding number of light neutrino species isN v =2.983±0.034. The lepton pair forward-backward asymmetry is used to derive the ratio of vector to axial-vector couplings of leptons:g V 2 (M Z 2 )/g A 2 (M Z 2 )=0.0058 ±0.0011. An application of these results to constrain one model with extraZ bosons is presented.I documenti in FLORE sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.