DETERMINATION OF Z0 RESONANCE PARAMETERS AND COUPLINGS FROM ITS HADRONIC AND LEPTONIC DECAYS

NUCLEAR PHYSICS B 367:3 (1991) 511-574

Authors:

P ABREU, W ADAM, F ADAMI, T ADYE, T AKESSON, GD ALEKSEEV, P ALLEN, S ALMEHED, F ALTED, SJ ALVSVAAG, U AMALDI, E ANASSONTZIS, P ANTILOGUS, WD APEL, RJ APSIMON, B ASMAN, P ASTIER, JE AUGUSTIN, A AUGUSTINUS, P BAILLON, P BAMBADE, F BARAO, G BARBIELLINI, DY BARDIN, A BARONCELLI, O BARRING, W BARTL, M BATTAGLIA, MJ BATES, M BAUBILLIER, KH BECKS, CJ BEESTON, M BEGALLI, P BEILLIERE, Y BELOKOPYTOV, P BELTRAN, D BENEDIC, JM BENLLOCH, M BERGGREN, D BERTRAND, S BIAGI, F BIANCHI, JH BIBBY, MS BILENKY, P BILLOIR, J BJARNE, D BLOCH, S BLYTH, PN BOGOLUBOV, T BOLOGNESE, M BONAPART, M BONESINI, W BONIVENTO, PSL BOOTH, M BORATAV, P BORGEAUD, G BORISOV, H BORNER, C BOSIO, O BOTNER, B BOUQUET, M BOZZO, S BRAIBANT, P BRANCHINI, KD BRAND, RA BRENNER, C BRICMAN, RCA BROWN, N BRUMMER, JM BRUNET, L BUGGE, T BURAN, H BURMEISTER, JAMA BUYTAERT, M CACCIA, M CALVI, AJC ROZAS, JE CAMPAGNE, A CAMPION, T CAMPORESI, V CANALE, F CAO, L CARROLL, C CASO, E CASTELLI, MVC GIMENEZ, A CATTAI, FR CAVALLO, L CERRITO, M CHAPKIN, P CHARPENTIER, P CHECCHIA, GA CHELKOV, L CHEVALIER, P CHLIAPNIKOV, V CHOROWICZ, R CIRIO, MP CLARA, P COLLINS, JL CONTRERAS, R CONTRI, G COSME, F COUCHOT, HB CRAWLEY, D CRENNELL, G CROSETTI, N CROSLAND, M CROZON, JC MAESTRO, S CZELLAR, S DAGORET, E DAHLJENSEN, B DALMAGNE, M DAM, G DAMGAARD, G DARBO, E DAUBIE, PD DAUNCEY, M DAVENPORT, P DAVID, A DEANGELIS, M DEBEER, H DEBOECK, W DEBOER, C DECLERCQ, MDMD LASO, N DEGROOT, C DELAVAISSIERE, B DELOTTO, A DEMIN, C DEFOIX, D DELIKARIS, S DELORME, P DELPIERRE, N DEMARIA, J DERKAOUI, L DICIACCIO, H DIJKSTRA, F DJAMA, J DOLBEAU, M DONSZELMANN, K DOROBA, M DRACOS, J DREES, M DRIS, Y DUFOUR, W DULINSKI, R DZHELYADIN, LO EEK, PAM EEROLA, T EKELOF, G EKSPONG, AE PEISERT, JP ENGEL, D FASSOULIOTIS, MF ALONSO, A FERRER, TA FILIPPAS, A FIRESTONE, H FOETH, E FOKITIS, P FOLEGATI, F FONTANELLI, H FORSBACH, B FRANEK, P FRENKIEL, DC FRIES, AG FRODESEN, R FRUHWIRTH, F FULDAQUENZER, K FURNIVAL, H FURSTENAU, J FUSTER, JM GAGO, G GALEAZZI, D GAMBA, C GARCIA, J GARCIA, U GASPARINI, P GAVILLET, EN GAZIS, JP GERBER, P GIACOMELLI, KW GLITZA, R GOKIELI, VM GOLOVATYUK, JJGY CADENAS, A GOOBAR, G GOPAL, M GORSKI, V GRACCO, A GRANT, F GRARD, E GRAZIANI, MH GROS, G GROSDIDIER, B GROSSETETE, S GUMENYUK, J GUY, F HAHN, M HAHN, S HAIDER, Z HAJDUK, A HAKANSSON, A HALLGREN, K HAMACHER, GH DEMONCHENAULT, FJ HARRIS, BW HECK, I HERBST, JJ HERNANDEZ, P HERQUET, H HERR, I HIETANEN, E HIGON, HJ HILKE, SD HODGSON, T HOFMOKL, R HOLMES, SO HOLMGREN, D HOLTHUIZEN, PF HONORE, JE HOOPER, M HOULDEN, J HRUBEC, PO HULTH, K HULTQVIST, D HUSSON, BD HYAMS, P IOANNOU, D ISENHOWER, PS IVERSEN, JN JACKSON, P JALOCHA, G JARLSKOG, P JARRY, B JEANMARIE, EK JOHANSSON, D JOHNSON, M JONKER, L JONSSON, P JUILLOT, G KALKANIS, G KALMUS, G KANTARDJIAN, F KAPUSTA, S KATSANEVAS, EC KATSOUFIS, R KERANEN, J KESTEMAN, BA KHOMENKO, NN KHOVANSKI, B KING, NJ KJAER, H KLEIN, W KLEMPT, A KLOVNING, P KLUIT, JH KOEHNE, B KOENE, P KOKKINIAS, M KOPF, M KORATZINOS, K KORCYL, AV KORYTOV, B KORZEN, V KOSTUKHIN, C KOURKOUMELIS, T KREUZBERGER, J KROLIKOWSKI, U KRUENERMARQUIS, W KRUPINSKI, W KUCEWICZ, K KULKA, K KURVINEN, C LACASTA, C LAMBROPOULOS, JW LAMSA, L LANCERI, V LAPIN, JP LAUGIER, R LAUHAKANGAS, G LEDER, F LEDROIT, J LEMONNE, G LENZEN, V LEPELTIER, A LETESSIERSELVON, D LIKO, E LIEB, E LILLETHUN, J LINDGREN, A LIPNIACKA, I LIPPI, R LLOSA, B LOERSTAD, M LOKAJICEK, JG LOKEN, MAL AGUERA, A LOPEZFERNANDEZ, M LOS, D LOUKAS, A LOUNIS, JJ LOZANO, R LUCOCK, P LUTZ, L LYONS, G MAEHLUM, J MAILLARD, A MALTEZOS, S MALTEZOS, F MANDL, J MARCO, M MARGONI, JC MARIN, A MARKOU, S MARTI, L MATHIS, F MATORRAS, C MATTEUZZI, G MATTHIAE, M MAZZUCATO, M MCCUBBIN, R MCKAY, R MCNULTY, E MENICHETTI, G MEOLA, C MERONI, WT MEYER, M MICHELOTTO, WA MITAROFF, GV MITSELMAKHER, U MJOERNMARK, T MOA, R MOELLER, K MOENIG, MR MONGE, P MORETTINI, H MUELLER, H MULLER, WJ MURRAY, G MUYATT, F NARAGHI, U NAUKORZEN, FL NAVARRIA, P NEGRI, BS NIELSEN, B NIJJHAR, V NIKOLAENKO, V OBRAZTSOV, AG OLSHEVSKI, R ORAVA, A OSTANKOV, A OURAOU, R PAIN, H PALKA, T PAPADOPOULOU, L PAPE, A PASSERI, M PEGORARO, V PEREVOZCHIKOV, M PERNICKA, A PERROTTA, F PIERRE, M PIMENTA, O PINGOT, A PINSENT, ME POL, G POLOK, P POROPAT, P PRIVITERA, A PULLIA, J PYYHTIA, D RADOJICIC, S RAGAZZI, WH RANGE, PN RATOFF, AL READ, NG REDAELLI, M REGLER, D REID, PB RENTON, LK RESVANIS, F RICHARD, M RICHARDSON, J RIDKY, G RINAUDO, I RODITI, A ROMERO, I RONCAGLIOLO, P RONCHESE, C RONNQVIST, EI ROSENBERG, U ROSSI, E ROSSO, P ROUDEAU, T ROVELLI, W RUCKSTUHL, V RUHLMANN, A RUIZ, K RYBICKI, H SAARIKKO, Y SACQUIN, J SALT, E SANCHEZ, J SANCHEZ, M SANNINO, M SCHAEFFER, S SCHAEL, H SCHNEIDER, F SCURI, AM SEGAR, R SEKULIN, M SESSA, G SETTE, R SEUFERT, RC SHELLARD, P SIEGRIST, S SIMONETTI, F SIMONETTO, AN SISSAKIAN, TB SKAALI, G SKJEVLING, G SMADJA, GR SMITH, N SMIRNOV, R SOSNOWSKI, TS SPASSOFF, E SPIRITI, S SQUARCIA, H STAECK, C STANESCU, G STAVROPOULOS, F STICHELBAUT, A STOCCHI, J STRAUSS, R STRUB, CJ STUBENRAUCH, M SZCZEKOWSKI, M SZEPTYCKA, P SZYMANSKI, T TABARELLI, S TAVERNIER, O TCHIKILEV, GE THEODOSIOU, A TILQUIN, J TIMMERMANS, VG TIMOFEEV, LG TKATCHEV, T TODOROV, DZ TOET, L TORTORA, MT TRAINOR, D TREILLE, U TREVISAN, W TRISCHUK, G TRISTRAM, C TRONCON, A TSIROU, EN TSYGANOV, M TURALA, R TURCHETTA, ML TURLUER, T TUUVA, IA TYAPKIN, M TYNDEL, S TZAMARIAS, B UEBERSCHAER, S UEBERSCHAER, O ULLALAND, VA UVAROV, G VALENTI, E VALLAZZA, JAV FERRER, GW VANAPELDOORN, P VANDAM, WK VANDONINCK, N VANEIJNDHOVEN, C VANDERVELDE, J VARELA, P VAZ, G VEGNI, J VELASCO, L VENTURA, W VENUS, F VERBEURE, LS VERTOGRADOV, L VIBERT, D VILANOVA, EV VLASOV, AS VODOPYANOV, M VOLLMER, S VOLPONI, G VOULGARIS, M VOUTILAINEN, V VRBA, H WAHLEN, C WALCK, F WALDNER, M WAYNE, P WEILHAMMER, J WERNER, AM WETHERELL, JH WICKENS, J WIKNE, GR WILKINSON, WSC WILLIAMS, M WINTER, D WORMALD, G WORMSER, K WOSCHNAGG, N YAMDAGNI, P YEPES, A ZAITSEV, A ZALEWSKA, P ZALEWSKI, E ZEVGOLATAKOS, G ZHANG, NI ZIMIN, M ZITO, R ZITOUN, RZ FUNCHAL, G ZUMERLE, J ZUNIGA

THE REACTION E+E--] GAMMA-GAMMA(GAMMA) AT Z0 ENERGIES

PHYSICS LETTERS B 268:2 (1991) 296-304

Authors:

P ABREU, W ADAM, F ADAMI, T ADYE, T AKESSON, GD ALEKSEEV, P ALLEN, S ALMEHED, F ALTED, SJ ALVSVAAG, U AMALDI, E ANASSONTZIS, P ANTILOGUS, WD APEL, RJ APSIMON, B ASMAN, P ASTIER, JE AUGUSTIN, A AUGUSTINUS, P BAILLON, P BAMBADE, F BARAO, G BARBIELLINI, DY BARDIN, A BARONCELLI, O BARRING, W BARTL, M BATTAGLIA, MJ BATES, M BAUBILLIER, KH BECKS, CJ BEESTON, M BEGALLI, P BEILLIERE, Y BELOKOPYTOV, P BELTRAN, D BENEDIC, JM BENLLOCH, M BERGGREN, D BERTRAND, S BIAGI, F BIANCHI, JH BIBBY, MS BILENKY, P BILLOIR, J BJARNE, D BLOCH, S BLYTH, PN BOGOLUBOV, T BOLOGNESE, M BONAPART, M BONESINI, W BONIVENTO, PSL BOOTH, M BORATAV, P BORGEAUD, G BORISOV, H BORNER, C BOSIO, O BOTNER, B BOUQUET, M BOZZO, S BRAIBANT, P BRANCHINI, KD BRAND, RA BRENNER, C BRICMAN, RCA BROWN, N BRUMMER, JM BRUNET, L BUGGE, T BURAN, H BURMEISTER, JAMA BUYTAERT, M CACCIA, M CALVI, AJC ROZAS, JE CAMPAGNE, A CAMPION, T CAMPORESI, V CANALE, F CAO, L CARROLL, C CASO, E CASTELLI, MVC GIMENEZ, A CATTAI, FR CAVALLO, L CERRITO, P CHARPENTIER, P CHECCHIA, GA CHELKOV, L CHEVALIER, P CHLIAPNIKOV, V CHOROWICZ, R CIRIO, MP CLARA, P COLLINS, JL CONTRERAS, R CONTRI, G COSME, F COUCHOT, HB CRAWLEY, D CRENNELL, G CROSETTI, N CROSLAND, M CROZON, JC MAESTRO, S CZELLAR, S DAGORET, E DAHLJENSEN, B DALMAGNE, M DAM, G DAMGAARD, G DARBO, E DAUBIE, PD DAUNCEY, M DAVENPORT, P DAVID, A DEANGELIS, M DEBEER, H DEBOECK, W DEBOER, C DECLERCQ, MDMD LASO, N DEGROOT, C DELAVAISSIERE, B DELOTTO, A DEMIN, C DEFOIX, D DELIKARIS, S DELORME, P DELPIERRE, N DEMARIA, J DERKAOUI, L DICIACCIO, H DIJKSTRA, F DJAMA, J DOLBEAU, M DONSZELMANN, K DOROBA, M DRACOS, J DREES, M DRIS, Y DUFOUR, W DULINSKI, R DZHELYADIN, LO EEK, PAM EEROLA, T EKELOF, G EKSPONG, AE PEISERT, JP ENGEL, D FASSOULIOTIS, A FENYUK, MF ALONSO, A FERRER, TA FILIPPAS, A FIRESTONE, H FOETH, E FOKITIS, P FOLEGATI, F FONTANELLI, H FORSBACH, B FRANEK, P FRENKIEL, DC FRIES, AG FRODESEN, R FRUHWIRTH, F FULDAQUENZER, K FURNIVAL, H FURSTENAU, J FUSTER, JM GAGO, G GALEAZZI, D GAMBA, C GARCIA, J GARCIA, U GASPARINI, P GAVILLET, EN GAZIS, JP GERBER, P GIACOMELLI, KW GLITZA, R GOKIELI, VM GOLOVATYUK, JJGY CADENAS, A GOOBAR, G GOPAL, M GORSKI, V GRACCO, A GRANT, F GRARD, E GRAZIANI, MH GROS, G GROSDIDIER, B GROSSETETE, S GUMENYUK, J GUY, F HAHN, M HAHN, S HAIDER, Z HAJDUK, A HAKANSSON, A HALLGREN, K HAMACHER, GH DEMONCHENAULT, FJ HARRIS, BW HECK, I HERBST, JJ HERNANDEZ, P HERQUET, H HERR, I HIETANEN, E HIGON, HJ HILKE, SD HODGSON, T HOFMOKL, R HOLMES, SO HOLMGREN, D HOLTHUIZEN, PF HONORE, JE HOOPER, M HOULDEN, J HRUBEC, PO HULTH, K HULTQVIST, D HUSSON, BD HYAMS, P IOANNOU, D ISENHOWER, PS IVERSEN, JN JACKSON, P JALOCHA, G JARLSKOG, P JARRY, B JEANMARIE, EK JOHANSSON, D JOHNSON, M JONKER, L JONSSON, P JUILLOT, G KALKANIS, G KALMUS, G KANTARDJIAN, F KAPUSTA, A KATARGIN, S KATSANEVAS, EC KATSOUFIS, R KERANEN, J KESTEMAN, BA KHOMENKO, NN KHOVANSKI, B KING, NJ KJAER, H KLEIN, W KLEMPT, A KLOVNING, P KLUIT, JH KOEHNE, B KOENE, P KOKKINIAS, M KOPF, M KORATZINOS, K KORCYL, AV KORYTOV, B KORZEN, V KOSTUKHIN, C KOURKOUMELIS, T KREUZBERGER, J KROLIKOWSKI, U KRUENERMARQUIS, W KRUPINSKI, W KUCEWICZ, K KURVINEN, C LACASTA, C LAMBROPOULOS, JW LAMSA, L LANCERI, V LAPIN, JP LAUGIER, R LAUHAKANGAS, G LEDER, F LEDROIT, J LEMONNE, G LENZEN, V LEPELTIER, A LETESSIERSELVON, D LIKO, E LIEB, E LILLETHUN, J LINDGREN, A LIPNIACKA, I LIPPI, R LLOSA, B LOERSTAD, M LOKAJICEK, JG LOKEN, MAL AGUERA, A LOPEZFERNANDEZ, M LOS, D LOUKAS, A LOUNIS, JJ LOZANO, R LUCOCK, P LUTZ, L LYONS, G MAEHLUM, J MAILLARD, A MALTEZOS, S MALTEZOS, F MANDL, J MARCO, M MARGONI, JC MARIN, A MARKOU, S MARTI, L MATHIS, F MATORRAS, C MATTEUZZI, G MATTHIAE, M MAZZUCATO, M MCCUBBIN, R MCKAY, R MCNULTY, E MENICHETTI, C MERONI, WT MEYER, M MICHELOTTO, WA MITAROFF, GV MITSELMAKHER, U MJOERNMARK, T MOA, R MOELLER, K MOENIG, MR MONGE, P MORETTINI, H MUELLER, H MULLER, WJ MURRAY, G MYATT, F NARAGHI, U NAUKORZEN, FL NAVARRIA, P NEGRI, BS NIELSEN, B NIJJHAR, V NIKOLAENKO, V OBRAZTSOV, AG OLSHEVSKI, R ORAVA, A OSTANKOV, A OURAOU, R PAIN, H PALKA, T PAPADOPOULOU, L PAPE, A PASSERI, M PEGORARO, V PEREVOZCHIKOV, M PERNICKA, A PERROTTA, F PIERRE, M PIMENTA, O PINGOT, A PINSENT, ME POL, G POLOK, P POROPAT, P PRIVITERA, A PULLIA, J PYYHTIA, D RADOJICIC, S RAGAZZI, WH RANGE, PN RATOFF, AL READ, NG REDAELLI, M REGLER, D REID, PB RENTON, LK RESVANIS, F RICHARD, M RICHARDSON, J RIDKY, G RINAUDO, I RODITI, A ROMERO, I RONCAGLIOLO, P RONCHESE, C RONNQVIST, EI ROSENBERG, U ROSSI, E ROSSO, P ROUDEAU, T ROVELLI, W RUCKSTUHL, V RUHLMANN, A RUIZ, K RYBICKI, H SAARIKKO, Y SACQUIN, J SALT, E SANCHEZ, J SANCHEZ, M SANNINO, M SCHAEFFER, S SCHAEL, H SCHNEIDER, F SCURI, AM SEGAR, R SEKULIN, M SESSA, G SETTE, R SEUFERT, RC SHELLARD, P SIEGRIST, S SIMONETTI, F SIMONETTO, AN SISSAKIAN, TB SKAALI, G SKJEVLING, G SMADJA, GR SMITH, R SOSNOWSKI, TS SPASSOFF, E SPIRITI, S SQUARCIA, H STAECK, C STANESCU, G STAVROPOULOS, F STICHELBAUT, A STOCCHI, J STRAUSS, R STRUB, CJ STUBENRAUCH, M SZCZEKOWSKI, M SZEPTYCKA, P SZYMANSKI, T TABARELLI, S TAVERNIER, GE THEODOSIOU, A TILQUIN, J TIMMERMANS, VG TIMOFEEV, LG TKATCHEV, T TODOROV, DZ TOET, L TORTORA, MT TRAINOR, D TREILLE, U TREVISAN, W TRISCHUK, G TRISTRAM, C TRONCON, A TSIROU, EN TSYGANOV, M TURALA, R TURCHETTA, ML TURLUER, T TUUVA, IA TYAPKIN, M TYNDEL, S TZAMARIAS, B UEBERSCHAER, S UEBERSCHAER, O ULLALAND, VA UVAROV, G VALENTI, E VALLAZZA, JAV FERRER, GW VANAPELDOORN, P VANDAM, WK VANDONINCK, N VANEIJNDHOVEN, C VANDERVELDE, J VARELA, P VAZ, G VEGNI, J VELASCO, L VENTURA, W VENUS, F VERBEURE, LS VERTOGRADOV, L VIBERT, D VILANOVA, EV VLASOV, AS VODOPYANOV, M VOLLMER, S VOLPONI, G VOULGARIS, M VOUTILAINEN, V VRBA, H WAHLEN, C WALCK, F WALDNER, M WAYNE, P WEILHAMMER, J WERNER, AM WETHERELL, JH WICKENS, J WIKNE, GR WILKINSON, WSC WILLIAMS, M WINTER, D WORMALD, G WORMSER, K WOSCHNAGG, N YAMDAGNI, P YEPES, A ZAITSEV, A ZALEWSKA, P ZALEWSKI, E ZEVGOLATAKOS, G ZHANG, NI ZIMIN, M ZITO, R ZITOUN, RZ FUNCHAL, G ZUMERLE, J ZUNIGA

Energy-energy correlations in hadronic final states from Z0 decays

Physics Letters B 252:1 (1990) 149-158

Authors:

P Abreu, W Adam, F Adami, T Ayde, GD Alekseev, P Allen, S Almehed, F Alted, SJ Alvsvaag, U Amaldi, E Anassontzis, WD Apel, B Asman, P Astier, JE Augustinus, A Augustinus, P Baillon, P Bambade, F Barao, G Barbiellini, DY Bardin, A Baroncelli, O Barring, W Bartl, MJ Bates, M Baubillier, KH Becks, CJ Beeston, P Beilliere, I Belokopytov, P Beltran, D Benedic, JM Benlloch, M Berggren, D Bertrand, S Biagi, F Bianchi, JH Bibby, MS Bilenky, P Billoir, J Biarne, D Bloch, PN Bogolubov, D Bollini, T Bolognese, M Bonapart, M Bonesini, PSL Booth, M Boratav, P Borgeaud, H Borner, C Bosio, O Botner, B Bouquet, M Bozzo, S Braibant, P Branchini, KD Brand, RA Brenner, C Bricman, RCA Brown, N Brummer, JM Brunet, L Bugge, T Buran, H Burmeister, JAMA Buytaert, M Caccia, M Calvi, AJ Camacho Rozas, JE Campagne, A Campion, T Camporesi, V Canale, F Cao, L Carroll, C Caso, E Castelli, MV Castillo Gimenez, A Cattai, FR Cavallo, L Cerrito, P Charpentier, P Checchia, GA Chelkov, L Chevalier, P Chliapnikov, V Chorowicz, R Cirio, MP Clara, JL Contreras, R Contri, G Cosme, F Couchot, HB Crawley, D Crennell, M Cresti, G Crosetti, N Crosland, M Crozon

Abstract:

We have studied the energy-energy angular correlations in hadronic final states from Z0 decay using the DELPHI detector at LEP. From a comparison with Monte Carlo calculations based on the exact second order QCD matrix element and string fragmentation we find that Λ (5) MS=104+25-20(stat.)+25-20(syst.) +3000)theor.). MeV, which corresponds to αs(91 GeV)=0.106±0.003(stat.)±0.003(syst.)+0.003 -0.000(theor). The theoretical error stems from different choices for the renormalization scale of αs. In the Monte Carlo simulation the scale of αs as well as the fragmentation parameters have been optimized to described reasonably well all aspects of multihadron production. © 1990.

Measurement of the partial width of the decay of the Z0 into charm quark pairs

Physics Letters B 252:1 (1990) 140-148

Authors:

P Abreu, W Adam, F Adami, T Adye, GD Alekseev, P Allen, S Almehed, F Alted, SJ Alvsvaag, U Amaldi, E Anassontzis, WD Apel, B Asman, P Astier, JE Augustin, A Augustinus, P Baillon, P Bambade, F Barao, G Barbiellini, DY Bardin, A Baroncelli, O Barring, W Bartl, MJ Bates, M Baubillier, KH Becks, CJ Beeston, P Beilliere, I Belokopytov, P Beltran, D Benedic, JM Benlloch, M Berggren, D Bertrand, S Biagi, F Bianchi, JH Bibby, MS Bilenky, P Billoir, J Bjarne, D Bloch, PN Bogolubov, D Bollini, T Bolognese, M Bonapart, M Bonesini, PSL Booth, M Boratay, P Borgeaud, H Borner, C Bosio, O Botner, B Bouquet, M Bozzo, S Braibant, P Branchini, KD Brand, RA Brenner, C Bricman, RCA Brown, N Brummer, JM Brunet, L Bugge, T Buran, H Burmeister, JAMA Buytaert, M Caccia, M Calvi, AJ Camacho Rozas, JE Campagne, A Campion, T Camporesi, V Canale, F Cao, L Carroll, C Caso, E Castelli, MV Castillo Gimenez, A Cattai, FR Cavallo, L Cerrito, P Charpentier, P Checchia, GA Chelkov, L Chevalier, P Chliapnikov, V Chorowicz, R Cirio, MP Clara, JL Contreras, R Contri, G Cosme, F Couchot, HB Crawley, D Crennell, M Cresti, G Crosetti, N Crosland, M Crozon

Abstract:

A determination of the partial width Γc c ̄ of the Z0 boson into charm quark pairs is presented, based on a total sample of 36 900 Z0 hadronic decays measured with the DELPHI detector at the LEP collider. The production rate of cc̄ events is derived from the inclusive analysis of charged pions coming from the decay of charmed meson D*+→D0π+ and D*-→ D ̄0 π- where the π± is constrained by kinematics to have a low pT with respect to the axis. The probability to produce these π± from D*± decay in cc̄ events is taken to be 0.31 ±_0.05 as measured at √s=10.55 GeV. The measured relative partial width Γc c ̄ Γh = 0.162± 0.030 (stat.) ±0.050 (syst.) is in good agreement with the standard moel value of 0.171. Together with our previous measurement of the total hadronic width Γh this implies Γc c ̄ = 282±53 (stat.)±88(syst.) MeV. © 1990.

LEPTOQUARK PRODUCTION AT THE LHC/LEP E-P COLLIDER

90 (1990) 1022-1032