In the pp→tt process the angular distributions of top and anti-top quarks are expected to present a subtle difference, which could be enhanced by processes not included in the Standard Model. This Letter presents a measurement of the charge asymmetry in events where the top-quark pair is produced with a large invariant mass. The analysis is performed on 20.3 fb-1 of pp collision data at √s=8TeV collected by the ATLAS experiment at the LHC, using reconstruction techniques specifically designed for the decay topology of highly boosted top quarks. The charge asymmetry in a fiducial region with large invariant mass of the top-quark pair (mtt>0.75 TeV) and an absolute rapidity difference of the top and anti-top quark candidates within -2<|yt|-|yt|<2 is measured to be 4.2±3.2%, in agreement with the Standard Model prediction at next-to-leading order. A differential measurement in three tt- mass bins is also presented.

Aad, G., Abbott, B., Abdallah, J., Abdinov, O., Aben, R., Abolins, M., et al. (2016). Measurement of the charge asymmetry in highly boosted top-quark pair production in √s=8 TeV pp collision data collected by the ATLAS experiment. PHYSICS LETTERS. SECTION B, 756, 52-71 [10.1016/j.physletb.2016.02.055].

Measurement of the charge asymmetry in highly boosted top-quark pair production in √s=8 TeV pp collision data collected by the ATLAS experiment

BELLAGAMBA, LORENZO;BIONDI, SILVIA;BOSCHERINI, DAVIDE;BRUNI, ALESSIA;BRUNI, GRAZIANO;DE CASTRO, STEFANO;FABBRI, LAURA;FRANCHINI, MATTEO;GABRIELLI, ALESSANDRO;GIACOBBE, BENEDETTO;LASAGNI MANGHI, FEDERICO;MASSA, LORENZO;MENGARELLI, ALBERTO;POLINI, ALESSANDRO;RINALDI, LORENZO;ROMANO, MARINO;SBARRA, CARLA;SEMPRINI CESARI, NICOLA;SIOLI, MAXIMILIANO;SPIGHI, ROBERTO;UCCHIELLI, GIULIA;VALENTINETTI, SARA;VILLA, MAURO;ZOCCOLI, ANTONIO;
2016

Abstract

In the pp→tt process the angular distributions of top and anti-top quarks are expected to present a subtle difference, which could be enhanced by processes not included in the Standard Model. This Letter presents a measurement of the charge asymmetry in events where the top-quark pair is produced with a large invariant mass. The analysis is performed on 20.3 fb-1 of pp collision data at √s=8TeV collected by the ATLAS experiment at the LHC, using reconstruction techniques specifically designed for the decay topology of highly boosted top quarks. The charge asymmetry in a fiducial region with large invariant mass of the top-quark pair (mtt>0.75 TeV) and an absolute rapidity difference of the top and anti-top quark candidates within -2<|yt|-|yt|<2 is measured to be 4.2±3.2%, in agreement with the Standard Model prediction at next-to-leading order. A differential measurement in three tt- mass bins is also presented.
2016
Aad, G., Abbott, B., Abdallah, J., Abdinov, O., Aben, R., Abolins, M., et al. (2016). Measurement of the charge asymmetry in highly boosted top-quark pair production in √s=8 TeV pp collision data collected by the ATLAS experiment. PHYSICS LETTERS. SECTION B, 756, 52-71 [10.1016/j.physletb.2016.02.055].
Aad, G.; Abbott, B.; Abdallah, J.; Abdinov, O.; Aben, R.; Abolins, M.; Abouzeid, O.S.; Abramowicz, H.; Abreu, H.; Abreu, R.; Abulaiti, Y.; Acharya, B....espandi
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11585/589049
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