A measurement of R-b using a lifetime-mass tag

Barate, R.; Buskulic, D.; Decamp, D.; Ghez, P.; Goy, C.; Lees, J.; Lucotte, A.; Minard, M.; Nief, J.; Pietrzyk, B.; Casado, M.; Chmeissani, M.; Comas, P.; Crespo, J.; Delfino, M.; Fernandez, E.; Fernandezbosman, M.; Garrido, L.; Juste, A.; Martinez, M.; Miquel, R.; Mir, L.; Orteu, S.; Padilla, C.; Park, I.; Pascual, A.; Perlas, J.; Riu, I.; Sanchez, F.; Teubert, F.; Colaleo, A.; Creanza, D.; Depalma, M.; Gelao, G.; Iaselli, G.; Maggi, G.; Maggi, M.; Marinelli, N.; Nuzzo, S.; Ranieri, A.; Raso, G.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Tricomi, A.; Zito, G.; Huang, X.; Lin, J.; Ouyang, Q.; Wang, T.; Xie, Y.; Xu, R.; Xue, S.; Zhang, J.; Zhang, L.; Zhao, W.; Abbaneo, D.; Alemany, R.; Becker, U.; Bazarko, A.; Brightthomas, P.; Cattaneo, M.; Cerutti, F.; Drevermann, H.; Forty, R.; Frank, M.; Hagelberg, R.; Harvey, J.; Janot, P.; Jost, B.; Kneringer, E.; Knobloch, J.; Lehraus, I.; Lutters, G.; Mato, P.; Minten, A.; Moneta, L.; Pacheco, A.; Pusztaszeri, J.; Ranjard, F.; Rensing, P.; Rizzo, G.; Rolandi, L.; Schlatter, D.; Schmitt, M.; Schneider, O.; Tejessy, W.; Tomalin, I.; Wachsmuth, H.; Wagner, A.; Ajaltouni, Z.; Barres, A.; Boyer, C.; Falvard, A.; Ferdi, C.; Gay, P.; Guicheney, C.; Henrard, P.; Jousset, J.; Michel, B.; Monteil, S.; Montret, J.; Pallin, D.; Perret, P.; Podlyski, F.; Proriol, J.; Rosnet, P.; Rossignol, J.; Fearnley, T.; Hansen, J.; Hansen, J.; Hansen, J.; Hansen, P.; Nilsson, B.; Rensch, B.; Waananen, A.; Daskalakis, G.; Kyriakis, A.; Markou, C.; Simopoulou, E.; Siotis, I.; Vayaki, A.; Blondel, A.; Bonneaud, G.; Brient, J.; Bourdon, P.; Rouge, A.; Rumpf, M.; Valassi, A.; Verderi, M.; Videau, H.; Candlin, D.; Parsons, M.; Focardi, E.; Parrini, G.; Zachariadou, K.; Corden, M.; Georgiopoulos, C.; Jaffe, D.; Antonelli, A.; Bencivenni, G.; Bologna, G.; Bossi, F.; Campana, P.; Capon, G.; Casper, D.; Chiarella, V.; Felici, G.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G.; Passalacqua, L.; Pepealtarelli, M.; Curtis, L.; Dorris, S.; Halley, A.; Knowles, I.; Lynch, J.; Oshea, V.; Raine, C.; Scarr, J.; Smith, K.; Teixeiradias, P.; Thompson, A.; Thomson, E.; Thomson, F.; Turnbull, R.; Geweniger, C.; Graefe, G.; Hanke, P.; Hansper, G.; Hepp, V.; Kluge, E.; Putzer, A.; Schmidt, M.; Sommer, J.; Tittel, K.; Werner, S.; Wunsch, M.; Beuselinck, R.; Binnie, D.; Cameron, W.; Dornan, P.; Girone, M.; Goodsir, S.; Martin, E.; Moutoussi, A.; Nash, J.; Sedgbeer, J.; Stacey, A.; Williams, M.; Dissertori, G.; Ghete, V.; Girtler, P.; Kuhn, D.; Rudolph, G.; Betteridge, A.; Bowdery, C.; Colrain, P.; Crawford, G.; Finch, A.; Foster, F.; Hughes, G.; Sloan, T.; Williams, M.; Galla, A.; Giehl, I.; Greene, A.; Hoffmann, C.; Jakobs, K.; Kleinknecht, K.; Quast, G.; Renk, B.; Rohne, E.; Sander, H.; Vangemmeren, P.; Zeitnitz, C.; Aubert, J.; Benchouk, C.; Bonissent, A.; Bujosa, G.; Calvet, D.; Carr, J.; Coyle, P.; Diaconu, C.; Etienne, F.; Konstantinidis, N.; Leroy, O.; Motsch, F.; Payre, P.; Rousseau, D.; Talby, M.; Sadouki, A.; Thulasidas, M.; Trabelsi, K.; Aleppo, M.R.A.; Ragusa, F.; Berlich, R.; Blum, W.; Brown, D.; Buscher, V.; Dietl, H.; Dydak, F.; Ganis, G.; Gotzhein, C.; Kroha, H.; Lutjens, G.; Lutz, G.; Manner, W.; Moser, H.; Richter, R.; Rosadoschlosser, A.; Schael, S.; Settles, R.; Seywerd, H.; Stdenis, R.; Stenzel, H.; Wiedenmann, W.; Wolf, G.; Boucrot, J.; Callot, O.; Chen, S.; Choi, Y.; Cordier, A.; Davier, M.; Duflot, L.; Grivaz, J.; Heusse, P.; Hocker, A.; Jacholkowska, J.; Jacquet, M.; Kim, D.; Lediberder, F.; Lefrancois, J.; Lutz, A.; Nikolic, I.; Schune, M.; Simion, S.; Tournefier, E.; Veillet, J.; Videau, I.; Zerwas, D.; Azzurri, P.; Bagliesi, G.; Batignani, G.; Bettarini, S.; Bozzi, C.; Calderini, G.; Carpinelli, M.; Ciocci, M.; Ciulli, V.; Dellorso, R.; Fantechi, R.; Ferrante, I.; Foa, L.; Forti, F.; Giassi, A.; Giorgi, M.; Gregorio, A.; Ligabue, F.; Lusiani, A.; Marrocchesi, P.; Messineo, A.; Palla, F.; Sanguinetti, G.; Sciaba, A.; Spagnolo, P.; Steinberger, J.; Tenchini, R.; Tonelli, G.; Vannini, C.; Venturi, A.; Verdini, P.; Blair, G.; Bryant, L.; Chambers, J.; Gao, Y.; Green, M.; Medcalf, T.; Perrodo, P.; Strong, J.; Vonwimmerspergtoeller, J.; Botterill, D.; Clifft, R.; Edgecock, T.; Haywood, S.; Maley, P.; Norton, P.; Thompson, J.; Wright, A.; Blochdevaux, B.; Colas, P.; Emery, S.; Kozanecki, W.; Lancon, E.; Lemaire, M.; Locci, E.; Perez, P.; Rander, J.; Renardy, J.; Roussarie, A.; Schuller, J.; Schwindling, J.; Trabelsi, A.; Vallage, B.; Black, S.; Dann, J.; Johnson, R.; Kim, H.; Litke, A.; Mcneil, M.; Taylor, G.; Booth, C.; Boswell, R.; Brew, C.; Cartwright, S.; Combley, F.; Kelly, M.; Lehto, M.; Newton, W.; Reeve, J.; Thompson, L.; Bohrer, A.; Brandt, S.; Cowan, G.; Grupen, C.; Saraiva, P.; Smolik, L.; Stephan, F.; Apollonio, M.; Bosisio, L.; Dellamarina, R.; Giannini, G.; Gobbo, B.; Musolino, G.; Rothberg, J.; Wasserbaech, S.; Armstrong, S.; Charles, E.; Elmer, P.; Ferguson, D.; Gao, Y.; Gonzalez, S.; Greening, T.; Hayes, O.; Hu, H.; Jin, S.; Mcnamara, P.; Nachtman, J.; Nielsen, J.; Orejudos, W.; Pan, Y.; Saadi, Y.; Scott, I.; Walsh, J.; Wu, S.; Wu, X.; Yamartino, J.; Zobernig, G.

doi:10.1016/S0370-2693(97)00406-1

ALEPH's published measurement of R-b = Gamma(Z --> b (b) over bar)/Gamma(Z --> hadrons) using a lifetime tag is updated using the full LEP 1 data sample. Considerable effort has been devoted to understanding systematic effects. Charm background is better controlled by combining the lifetime tag with a tag based on the b/c hadron mass difference. Furthermore, the algorithm used to reconstruct the event primary vertex is designed so as to reduce correlations between the two hemispheres of an event. The value of R-b is measured to be 0.2167 +/- 0.0011(stat) +/- 0.0013(syst).

A measurement of R-b using a lifetime-mass tag / R. Barate, D. Buskulic, D. Decamp, P. Ghez, C. Goy, J. Lees, A. Lucotte, M. Minard, J. Nief, B. Pietrzyk, M. Casado, M. Chmeissani, P. Comas, J. Crespo, M. Delfino, E. Fernandez, M. FernandezBosman, L. Garrido, A. Juste, M. Martinez, R. Miquel, L. Mir, S. Orteu, C. Padilla, I. Park, A. Pascual, J. Perlas, I. Riu, F. Sanchez, F. Teubert, A. Colaleo, D. Creanza, M. dePalma, G. Gelao, G. Iaselli, G. Maggi, M. Maggi, N. Marinelli, S. Nuzzo, A. Ranieri, G. Raso, F. Ruggieri, G. Selvaggi, L. Silvestris, P. Tempesta, A. Tricomi, G. Zito, X. Huang, J. Lin, Q. Ouyang, T. Wang, Y. Xie, R. Xu, S. Xue, J. Zhang, L. Zhang, W. Zhao, D. Abbaneo, R. Alemany, U. Becker, A. Bazarko, P. BrightThomas, M. Cattaneo, F. Cerutti, H. Drevermann, R. Forty, M. Frank, R. Hagelberg, J. Harvey, P. Janot, B. Jost, E. Kneringer, J. Knobloch, I. Lehraus, G. Lutters, P. Mato, A. Minten, L. Moneta, A. Pacheco, J. Pusztaszeri, F. Ranjard, P. Rensing, G. Rizzo, L. Rolandi, D. Schlatter, M. Schmitt, O. Schneider, W. Tejessy, I. Tomalin, H. Wachsmuth, A. Wagner, Z. Ajaltouni, A. Barres, C. Boyer, A. Falvard, C. Ferdi, P. Gay, C. Guicheney, P. Henrard, J. Jousset, B. Michel, S. Monteil, J. Montret, D. Pallin, P. Perret, F. Podlyski, J. Proriol, P. Rosnet, J. Rossignol, T. Fearnley, J. Hansen, J. Hansen, J. Hansen, P. Hansen, B. Nilsson, B. Rensch, A. Waananen, G. Daskalakis, A. Kyriakis, C. Markou, E. Simopoulou, I. Siotis, A. Vayaki, A. Blondel, G. Bonneaud, J. Brient, P. Bourdon, A. Rouge, M. Rumpf, A. Valassi, M. Verderi, H. Videau, D. Candlin, M. Parsons, E. Focardi, G. Parrini, K. Zachariadou, M. Corden, C. Georgiopoulos, D. Jaffe, A. Antonelli, G. Bencivenni, G. Bologna, F. Bossi, P. Campana, G. Capon, D. Casper, V. Chiarella, G. Felici, P. Laurelli, G. Mannocchi, F. Murtas, G. Murtas, L. Passalacqua, M. PepeAltarelli, L. Curtis, S. Dorris, A. Halley, I. Knowles, J. Lynch, V. OShea, C. Raine, J. Scarr, K. Smith, P. TeixeiraDias, A. Thompson, E. Thomson, F. Thomson, R. Turnbull, C. Geweniger, G. Graefe, P. Hanke, G. Hansper, V. Hepp, E. Kluge, A. Putzer, M. Schmidt, J. Sommer, K. Tittel, S. Werner, M. Wunsch, R. Beuselinck, D. Binnie, W. Cameron, P. Dornan, M. Girone, S. Goodsir, E. Martin, A. Moutoussi, J. Nash, J. Sedgbeer, A. Stacey, M. Williams, G. Dissertori, V. Ghete, P. Girtler, D. Kuhn, G. Rudolph, A. Betteridge, C. Bowdery, P. Colrain, G. Crawford, A. Finch, F. Foster, G. Hughes, T. Sloan, M. Williams, A. Galla, I. Giehl, A. Greene, C. Hoffmann, K. Jakobs, K. Kleinknecht, G. Quast, B. Renk, E. Rohne, H. Sander, P. vanGemmeren, C. Zeitnitz, J. Aubert, C. Benchouk, A. Bonissent, G. Bujosa, D. Calvet, J. Carr, P. Coyle, C. Diaconu, F. Etienne, N. Konstantinidis, O. Leroy, F. Motsch, P. Payre, D. Rousseau, M. Talby, A. Sadouki, M. Thulasidas, K. Trabelsi, M.R.A. Aleppo, F. Ragusa, R. Berlich, W. Blum, D. Brown, V. Buscher, H. Dietl, F. Dydak, G. Ganis, C. Gotzhein, H. Kroha, G. Lutjens, G. Lutz, W. Manner, H. Moser, R. Richter, A. RosadoSchlosser, S. Schael, R. Settles, H. Seywerd, R. StDenis, H. Stenzel, W. Wiedenmann, G. Wolf, J. Boucrot, O. Callot, S. Chen, Y. Choi, A. Cordier, M. Davier, L. Duflot, J. Grivaz, P. Heusse, A. Hocker, J. Jacholkowska, M. Jacquet, D. Kim, F. LeDiberder, J. Lefrancois, A. Lutz, I. Nikolic, M. Schune, S. Simion, E. Tournefier, J. Veillet, I. Videau, D. Zerwas, P. Azzurri, G. Bagliesi, G. Batignani, S. Bettarini, C. Bozzi, G. Calderini, M. Carpinelli, M. Ciocci, V. Ciulli, R. DellOrso, R. Fantechi, I. Ferrante, L. Foa, F. Forti, A. Giassi, M. Giorgi, A. Gregorio, F. Ligabue, A. Lusiani, P. Marrocchesi, A. Messineo, F. Palla, G. Sanguinetti, A. Sciaba, P. Spagnolo, J. Steinberger, R. Tenchini, G. Tonelli, C. Vannini, A. Venturi, P. Verdini, G. Blair, L. Bryant, J. Chambers, Y. Gao, M. Green, T. Medcalf, P. Perrodo, J. Strong, J. vonWimmerspergToeller, D. Botterill, R. Clifft, T. Edgecock, S. Haywood, P. Maley, P. Norton, J. Thompson, A. Wright, B. BlochDevaux, P. Colas, S. Emery, W. Kozanecki, E. Lancon, M. Lemaire, E. Locci, P. Perez, J. Rander, J. Renardy, A. Roussarie, J. Schuller, J. Schwindling, A. Trabelsi, B. Vallage, S. Black, J. Dann, R. Johnson, H. Kim, A. Litke, M. McNeil, G. Taylor, C. Booth, R. Boswell, C. Brew, S. Cartwright, F. Combley, M. Kelly, M. Lehto, W. Newton, J. Reeve, L. Thompson, A. Bohrer, S. Brandt, G. Cowan, C. Grupen, P. Saraiva, L. Smolik, F. Stephan, M. Apollonio, L. Bosisio, R. DellaMarina, G. Giannini, B. Gobbo, G. Musolino, J. Rothberg, S. Wasserbaech, S. Armstrong, E. Charles, P. Elmer, D. Ferguson, Y. Gao, S. Gonzalez, T. Greening, O. Hayes, H. Hu, S. Jin, P. McNamara, J. Nachtman, J. Nielsen, W. Orejudos, Y. Pan, Y. Saadi, I. Scott, J. Walsh, S. Wu, X. Wu, J. Yamartino, G. Zobernig. - In: PHYSICS LETTERS. SECTION B. - ISSN 0370-2693. - 401:1/2(1997), pp. 150-162.

A measurement of R-b using a lifetime-mass tag

R. Barate;D. Buskulic;D. Decamp;P. Ghez;C. Goy;J. Lees;A. Lucotte;M. Minard;J. Nief;B. Pietrzyk;M. Casado;M. Chmeissani;P. Comas;J. Crespo;M. Delfino;E. Fernandez;M. FernandezBosman;L. Garrido;A. Juste;M. Martinez;R. Miquel;L. Mir;S. Orteu;C. Padilla;I. Park;A. Pascual;J. Perlas;I. Riu;F. Sanchez;F. Teubert;A. Colaleo;D. Creanza;M. dePalma;G. Gelao;G. Iaselli;G. Maggi;M. Maggi;N. Marinelli;S. Nuzzo;A. Ranieri;G. Raso;F. Ruggieri;G. Selvaggi;L. Silvestris;P. Tempesta;A. Tricomi;G. Zito;X. Huang;J. Lin;Q. Ouyang;T. Wang;Y. Xie;R. Xu;S. Xue;J. Zhang;L. Zhang;W. Zhao;D. Abbaneo;R. Alemany;U. Becker;A. Bazarko;P. BrightThomas;M. Cattaneo;F. Cerutti;H. Drevermann;R. Forty;M. Frank;R. Hagelberg;J. Harvey;P. Janot;B. Jost;E. Kneringer;J. Knobloch;I. Lehraus;G. Lutters;P. Mato;A. Minten;L. Moneta;A. Pacheco;J. Pusztaszeri;F. Ranjard;P. Rensing;G. Rizzo;L. Rolandi;D. Schlatter;M. Schmitt;O. Schneider;W. Tejessy;I. Tomalin;H. Wachsmuth;A. Wagner;Z. Ajaltouni;A. Barres;C. Boyer;A. Falvard;C. Ferdi;P. Gay;C. Guicheney;P. Henrard;J. Jousset;B. Michel;S. Monteil;J. Montret;D. Pallin;P. Perret;F. Podlyski;J. Proriol;P. Rosnet;J. Rossignol;T. Fearnley;J. Hansen;J. Hansen;J. Hansen;P. Hansen;B. Nilsson;B. Rensch;A. Waananen;G. Daskalakis;A. Kyriakis;C. Markou;E. Simopoulou;I. Siotis;A. Vayaki;A. Blondel;G. Bonneaud;J. Brient;P. Bourdon;A. Rouge;M. Rumpf;A. Valassi;M. Verderi;H. Videau;D. Candlin;M. Parsons;E. Focardi;G. Parrini;K. Zachariadou;M. Corden;C. Georgiopoulos;D. Jaffe;A. Antonelli;G. Bencivenni;G. Bologna;F. Bossi;P. Campana;G. Capon;D. Casper;V. Chiarella;G. Felici;P. Laurelli;G. Mannocchi;F. Murtas;G. Murtas;L. Passalacqua;M. PepeAltarelli;L. Curtis;S. Dorris;A. Halley;I. Knowles;J. Lynch;V. OShea;C. Raine;J. Scarr;K. Smith;P. TeixeiraDias;A. Thompson;E. Thomson;F. Thomson;R. Turnbull;C. Geweniger;G. Graefe;P. Hanke;G. Hansper;V. Hepp;E. Kluge;A. Putzer;M. Schmidt;J. Sommer;K. Tittel;S. Werner;M. Wunsch;R. Beuselinck;D. Binnie;W. Cameron;P. Dornan;M. Girone;S. Goodsir;E. Martin;A. Moutoussi;J. Nash;J. Sedgbeer;A. Stacey;M. Williams;G. Dissertori;V. Ghete;P. Girtler;D. Kuhn;G. Rudolph;A. Betteridge;C. Bowdery;P. Colrain;G. Crawford;A. Finch;F. Foster;G. Hughes;T. Sloan;M. Williams;A. Galla;I. Giehl;A. Greene;C. Hoffmann;K. Jakobs;K. Kleinknecht;G. Quast;B. Renk;E. Rohne;H. Sander;P. vanGemmeren;C. Zeitnitz;J. Aubert;C. Benchouk;A. Bonissent;G. Bujosa;D. Calvet;J. Carr;P. Coyle;C. Diaconu;F. Etienne;N. Konstantinidis;O. Leroy;F. Motsch;P. Payre;D. Rousseau;M. Talby;A. Sadouki;M. Thulasidas;K. Trabelsi;M.R.A. Aleppo;F. Ragusa;R. Berlich;W. Blum;D. Brown;V. Buscher;H. Dietl;F. Dydak;G. Ganis;C. Gotzhein;H. Kroha;G. Lutjens;G. Lutz;W. Manner;H. Moser;R. Richter;A. RosadoSchlosser;S. Schael;R. Settles;H. Seywerd;R. StDenis;H. Stenzel;W. Wiedenmann;G. Wolf;J. Boucrot;O. Callot;S. Chen;Y. Choi;A. Cordier;M. Davier;L. Duflot;J. Grivaz;P. Heusse;A. Hocker;J. Jacholkowska;M. Jacquet;D. Kim;F. LeDiberder;J. Lefrancois;A. Lutz;I. Nikolic;M. Schune;S. Simion;E. Tournefier;J. Veillet;I. Videau;D. Zerwas;P. Azzurri;G. Bagliesi;G. Batignani;S. Bettarini;C. Bozzi;G. Calderini;M. Carpinelli;M. Ciocci;V. Ciulli;R. DellOrso;R. Fantechi;I. Ferrante;L. Foa;F. Forti;A. Giassi;M. Giorgi;A. Gregorio;F. Ligabue;A. Lusiani;P. Marrocchesi;A. Messineo;F. Palla;G. Sanguinetti;A. Sciaba;P. Spagnolo;J. Steinberger;R. Tenchini;G. Tonelli;C. Vannini;A. Venturi;P. Verdini;G. Blair;L. Bryant;J. Chambers;Y. Gao;M. Green;T. Medcalf;P. Perrodo;J. Strong;J. vonWimmerspergToeller;D. Botterill;R. Clifft;T. Edgecock;S. Haywood;P. Maley;P. Norton;J. Thompson;A. Wright;B. BlochDevaux;P. Colas;S. Emery;W. Kozanecki;E. Lancon;M. Lemaire;E. Locci;P. Perez;J. Rander;J. Renardy;A. Roussarie;J. Schuller;J. Schwindling;A. Trabelsi;B. Vallage;S. Black;J. Dann;R. Johnson;H. Kim;A. Litke;M. McNeil;G. Taylor;C. Booth;R. Boswell;C. Brew;S. Cartwright;F. Combley;M. Kelly;M. Lehto;W. Newton;J. Reeve;L. Thompson;A. Bohrer;S. Brandt;G. Cowan;C. Grupen;P. Saraiva;L. Smolik;F. Stephan;M. Apollonio;L. Bosisio;R. DellaMarina;G. Giannini;B. Gobbo;G. Musolino;J. Rothberg;S. Wasserbaech;S. Armstrong;E. Charles;P. Elmer;D. Ferguson;Y. Gao;S. Gonzalez;T. Greening;O. Hayes;H. Hu;S. Jin;P. McNamara;J. Nachtman;J. Nielsen;W. Orejudos;Y. Pan;Y. Saadi;I. Scott;J. Walsh;S. Wu;X. Wu;J. Yamartino;G. Zobernig

1997

Abstract

ALEPH's published measurement of R-b = Gamma(Z --> b (b) over bar)/Gamma(Z --> hadrons) using a lifetime tag is updated using the full LEP 1 data sample. Considerable effort has been devoted to understanding systematic effects. Charm background is better controlled by combining the lifetime tag with a tag based on the b/c hadron mass difference. Furthermore, the algorithm used to reconstruct the event primary vertex is designed so as to reduce correlations between the two hemispheres of an event. The value of R-b is measured to be 0.2167 +/- 0.0011(stat) +/- 0.0013(syst).

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Scheda completa (DC)

	Settori scientifico-disciplinari dell'articolo
	
			Settore FIS/01 - Fisica Sperimentale
Settore FIS/04 - Fisica Nucleare e Subnucleare
		
	Data di pubblicazione
	
			1997
		
	Rivista in ANCE
	
			PHYSICS LETTERS. SECTION B
		
	DOI
	
			https://dx.doi.org/10.1016/S0370-2693(97)00406-1
		
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			Article (author)
		
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			01 - Articolo su periodico

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