Measurement of the mass difference between top and anti-top quarks in pp collisions at √s = 7 TeV using the ATLAS detector
A measurement of the mass difference between top and anti-top quarks is presented. In a 4.7 fb−1 data sample of proton–proton collisions at √s = 7 TeV recorded with the ATLAS detector at the LHC, events consistent with tt ̄ production and decay into a single charged lepton final state are reconstruc...
| Authors: | , , , , , , |
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| Format: | article |
| Status: | Published version |
| Publication Date: | 2014 |
| Country: | Argentina |
| Institution: | Universidad Nacional de La Plata |
| Repository: | SEDICI (UNLP) |
| Language: | English |
| OAI Identifier: | oai:sedici.unlp.edu.ar:10915/77608 |
| Online Access: | http://sedici.unlp.edu.ar/handle/10915/77608 |
| Access Level: | Open access |
| Keyword: | Física top quarks anti-top quarks pp collisions ATLAS detector |
| Summary: | A measurement of the mass difference between top and anti-top quarks is presented. In a 4.7 fb−1 data sample of proton–proton collisions at √s = 7 TeV recorded with the ATLAS detector at the LHC, events consistent with tt ̄ production and decay into a single charged lepton final state are reconstructed. For each event, the mass difference between the top and anti-top quark candidate is calculated. A two b-tag requirement is used in order to reduce the background contribution. A maximum likelihood fit to these per-event mass differences yields <math><mi mathvariant="normal" is="true">Δ</mi><mi is="true">m</mi><mo is="true">≡</mo><msub is="true"><mrow is="true"><mi is="true">m</mi></mrow><mrow is="true"><mi is="true">t</mi></mrow></msub><mo is="true">−</mo><msub is="true"><mrow is="true"><mi is="true">m</mi></mrow><mrow is="true"><mover accent="true" is="true"><mrow is="true"><mi is="true">t</mi></mrow><mrow is="true"><mo is="true">¯</mo></mrow></mover></mrow></msub><mo is="true">=</mo><mn is="true">0.67</mn><mo is="true">±</mo><mn is="true">0.61</mn><mspace width="0.2em" is="true"></mspace><mo stretchy="false" is="true">(</mo><mtext is="true">stat</mtext><mo stretchy="false" is="true">)</mo><mo is="true">±</mo><mn is="true">0.41</mn><mspace width="0.2em" is="true"></mspace><mo stretchy="false" is="true">(</mo><mtext is="true">syst</mtext><mo stretchy="false" is="true">)</mo><mtext is="true"> GeV</mtext></math>, consistent with CPT invariance. |
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