Abstract: The production cross sections of top-quark pairs in association with massive vector bosons have been measured using data from pp collisions at √s = 8 TeV. The dataset corresponds to an integrated luminosity of 20.3 fb−1 collected by the ATLAS detector in 2012 at the LHC. Final states with two, three or four leptons are considered. A fit to the data considering the tt¯W and tt¯Z processes simultaneously yields a significance of 5.0σ (4.2σ) over the background-only hypothesis for tt¯W (tt¯Z) production. The measured cross sections are (Formula presented.) fb and (Formula presented.) fb. The background-only hypothesis with neither tt¯W nor tt¯Z production is excluded at 7.1σ. All measurements are consistent with next-to-leading-order calculations for the tt¯W and tt¯Z processes.[Figure not available: see fulltext.] copyright 2015, The Author(s).
Measurement of the tt¯W and tt¯Z production cross sections in pp collisions at √s = 8 TeV with the ATLAS detector / Aad, G., Aloisio, A., Alviggi, M., Canale, V., DELLA PIETRA, M., DELLA VOLPE, D., Merola, L., Conventi, F., Perrella, S., Rossi, E., SANCHEZ PINEDA, A.R., Carlino, G., DE ASMUNDIS, R., DI DONATO, C., Doria, A., Iengo, P., Izzo, V., Sekhniaidze, G., Cirotto, F., Et, A.l.. - In: JOURNAL OF HIGH ENERGY PHYSICS. - ISSN 1029-8479. - 2015:11(2015), pp. 1-48. [10.1007/JHEP11(2015)172]
Measurement of the tt¯W and tt¯Z production cross sections in pp collisions at √s = 8 TeV with the ATLAS detector
ALOISIO, ALBERTO;ALVIGGI, MARIAGRAZIA;CANALE, VINCENZO;DELLA PIETRA, MASSIMO;DELLA VOLPE, DOMENICO;MEROLA, LEONARDO;CONVENTI, FRANCESCO;PERRELLA, SABRINA;ROSSI, ELVIRA;SANCHEZ PINEDA, ARTURO RODOLFO;CARLINO, GIANPAOLO;DE ASMUNDIS, Riccardo;DI DONATO, CAMILLA;IENGO, PAOLO;IZZO, VINCENZO;CIROTTO, FRANCESCO;
2015
Abstract
Abstract: The production cross sections of top-quark pairs in association with massive vector bosons have been measured using data from pp collisions at √s = 8 TeV. The dataset corresponds to an integrated luminosity of 20.3 fb−1 collected by the ATLAS detector in 2012 at the LHC. Final states with two, three or four leptons are considered. A fit to the data considering the tt¯W and tt¯Z processes simultaneously yields a significance of 5.0σ (4.2σ) over the background-only hypothesis for tt¯W (tt¯Z) production. The measured cross sections are (Formula presented.) fb and (Formula presented.) fb. The background-only hypothesis with neither tt¯W nor tt¯Z production is excluded at 7.1σ. All measurements are consistent with next-to-leading-order calculations for the tt¯W and tt¯Z processes.[Figure not available: see fulltext.] copyright 2015, The Author(s).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.


