A search for Higgs boson production in association with a pair of top quarks (tt¯ H) is performed, where the Higgs boson decays to bb¯, and both top quarks decay hadronically. The data used correspond to an integrated luminosity of 20.3 fb−1 of pp collisions at √s = 8 TeV collected with the ATLAS detector at the Large Hadron Collider. The search selects events with at least six energetic jets and uses a boosted decision tree algorithm to discriminate between signal and Standard Model background. The dominant multijet background is estimated using a dedicated data-driven technique. For a Higgs boson mass of 125 GeV, an upper limit of 6.4 (5.4) times the Standard Model cross section is observed (expected) at 95% confidence level. The best-fit value for the signal strength is μ = 1.6 ± 2.6 times the Standard Model expectation for mH = 125 GeV. Combining all tt¯ H searches carried out by ATLAS at √s = 8 and 7 TeV, an observed (expected) upper limit of 3.1 (1.4) times the Standard Model expectation is obtained at 95% confidence level, with a signal strength μ = 1.7 ± 0.8. © 2016, The Author(s).
Search for the Standard Model Higgs boson decaying into bb¯ produced in association with top quarks decaying hadronically in pp collisions at √s = 8 TeV with the ATLAS detector / Aad, G., Aloisio, A., Alviggi, M., Canale, V., DELLA VOLPE, D., Merola, L., Conventi, F., DELLA PIETRA, M., Giordano, R., Perrella, S., Rossi, E., Cirotto, F., SANCHEZ PINEDA, A.R., Carlino, G., DE ASMUNDIS, R., DI DONATO, C., Doria, A., Iengo, P., Izzo, V., Sekhniaidze, G., et al.. - In: JOURNAL OF HIGH ENERGY PHYSICS. - ISSN 1029-8479. - 2016:5(2016). [10.1007/JHEP05(2016)160]
Search for the Standard Model Higgs boson decaying into bb¯ produced in association with top quarks decaying hadronically in pp collisions at √s = 8 TeV with the ATLAS detector
ALOISIO, ALBERTO;ALVIGGI, MARIAGRAZIA;CANALE, VINCENZO;DELLA VOLPE, DOMENICO;MEROLA, LEONARDO;CONVENTI, FRANCESCO;DELLA PIETRA, MASSIMO;GIORDANO, RAFFAELE;PERRELLA, SABRINA;ROSSI, ELVIRA;CIROTTO, FRANCESCO;SANCHEZ PINEDA, ARTURO RODOLFO;CARLINO, GIANPAOLO;DE ASMUNDIS, Riccardo;DI DONATO, CAMILLA;IENGO, PAOLO;IZZO, VINCENZO;
2016
Abstract
A search for Higgs boson production in association with a pair of top quarks (tt¯ H) is performed, where the Higgs boson decays to bb¯, and both top quarks decay hadronically. The data used correspond to an integrated luminosity of 20.3 fb−1 of pp collisions at √s = 8 TeV collected with the ATLAS detector at the Large Hadron Collider. The search selects events with at least six energetic jets and uses a boosted decision tree algorithm to discriminate between signal and Standard Model background. The dominant multijet background is estimated using a dedicated data-driven technique. For a Higgs boson mass of 125 GeV, an upper limit of 6.4 (5.4) times the Standard Model cross section is observed (expected) at 95% confidence level. The best-fit value for the signal strength is μ = 1.6 ± 2.6 times the Standard Model expectation for mH = 125 GeV. Combining all tt¯ H searches carried out by ATLAS at √s = 8 and 7 TeV, an observed (expected) upper limit of 3.1 (1.4) times the Standard Model expectation is obtained at 95% confidence level, with a signal strength μ = 1.7 ± 0.8. © 2016, The Author(s).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
