Search for direct pair production of the top squark in all-hadronic final states in proton-proton collisions at √s = 8 TeV with the ATLAS detector

The results of a search for direct pair production of the scalar partner to the top quark using an integrated luminosity of 20.1 fb−1 of proton-proton collision data at √s = 8 TeV recorded with the ATLAS detector at the LHC are reported. The top squark is assumed to decay via <math xmlns="ht...

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Detalles Bibliográficos
Autores principales: Alconada Verzini, María Josefina, Alonso, Francisco, Anduaga, Xabier Sebastián, Dova, María Teresa, Monticelli, Fernando Gabriel, Wahlberg, Hernán Pablo, The ATLAS Collaboration
Formato: Articulo
Lenguaje:Inglés
Publicado: 2014
Materias:
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/79010
Aporte de:SEDICI (UNLP) de Universidad Nacional de La Plata Ver origen
id I19-R120-10915-79010
record_format dspace
institution Universidad Nacional de La Plata
institution_str I-19
repository_str R-120
collection SEDICI (UNLP)
language Inglés
topic Ciencias Exactas
Física
hadron-hadron scattering
supersymmetry
top squark
proton-proton scattering
spellingShingle Ciencias Exactas
Física
hadron-hadron scattering
supersymmetry
top squark
proton-proton scattering
Alconada Verzini, María Josefina
Alonso, Francisco
Anduaga, Xabier Sebastián
Dova, María Teresa
Monticelli, Fernando Gabriel
Wahlberg, Hernán Pablo
The ATLAS Collaboration
Search for direct pair production of the top squark in all-hadronic final states in proton-proton collisions at √s = 8 TeV with the ATLAS detector
topic_facet Ciencias Exactas
Física
hadron-hadron scattering
supersymmetry
top squark
proton-proton scattering
description The results of a search for direct pair production of the scalar partner to the top quark using an integrated luminosity of 20.1 fb−1 of proton-proton collision data at √s = 8 TeV recorded with the ATLAS detector at the LHC are reported. The top squark is assumed to decay via <math xmlns="http://www.w3.org/1998/Math/MathML"><mover><mi>t</mi><mo accent="false">¯<!-- ¯ --></mo></mover><mtext> </mtext><mo stretchy="false">→<!-- → --></mo><mi>t</mi><msubsup><mrow class="MJX-TeXAtom-ORD"><mover><mi>χ<!-- χ --></mi><mo accent="false">¯<!-- ¯ --></mo></mover></mrow><mn>1</mn><mn>0</mn></msubsup></math> or <math xmlns="http://www.w3.org/1998/Math/MathML"><mover><mi>t</mi><mo accent="false">¯<!-- ¯ --></mo></mover><mtext> </mtext><mo stretchy="false">→<!-- → --></mo><mi>b</mi><msubsup><mrow class="MJX-TeXAtom-ORD"><mover><mi>χ<!-- χ --></mi><mo accent="false">¯<!-- ¯ --></mo></mover></mrow><mn>1</mn><mrow class="MJX-TeXAtom-ORD"><mo>±<!-- ± --></mo></mrow></msubsup><mtext> </mtext><mo stretchy="false">→<!-- → --></mo><mi>b</mi><msup><mrow class="MJX-TeXAtom-ORD"><mi>W</mi></mrow><mrow class="MJX-TeXAtom-ORD"><mrow><mo>(</mo><mo>∗<!-- ∗ --></mo><mo>)</mo></mrow></mrow></msup><msubsup><mrow class="MJX-TeXAtom-ORD"><mover><mi>χ<!-- χ --></mi><mo accent="false">¯<!-- ¯ --></mo></mover></mrow><mn>1</mn><mn>0</mn></msubsup></math>, where <math xmlns="http://www.w3.org/1998/Math/MathML"><msubsup><mrow class="MJX-TeXAtom-ORD"><mover><mi>χ<!-- χ --></mi><mo accent="false">¯<!-- ¯ --></mo></mover></mrow><mn>1</mn><mn>0</mn></msubsup><mtext> </mtext><mrow><mo>(</mo><msubsup><mrow class="MJX-TeXAtom-ORD"><mover><mi>χ<!-- χ --></mi><mo accent="false">¯<!-- ¯ --></mo></mover></mrow><mn>1</mn><mrow class="MJX-TeXAtom-ORD"><mo>±<!-- ± --></mo></mrow></msubsup><mo>)</mo></mrow></math> denotes the lightest neutralino (chargino) in supersymmetric models. The search targets a fullyhadronic final state in events with four or more jets and large missing transverse momentum. No significant excess over the Standard Model background prediction is observed, and exclusion limits are reported in terms of the top squark and neutralino masses and as a function of the branching fraction of <math xmlns="http://www.w3.org/1998/Math/MathML"><mover><mi>t</mi><mo accent="false">¯<!-- ¯ --></mo></mover><mtext> </mtext><mo stretchy="false">→<!-- → --></mo><mi>t</mi><msubsup><mrow class="MJX-TeXAtom-ORD"><mover><mi>χ<!-- χ --></mi><mo accent="false">¯<!-- ¯ --></mo></mover></mrow><mn>1</mn><mn>0</mn></msubsup></math>. For a branching fraction of 100%, top squark masses in the range 270–645 GeV are excluded for <math xmlns="http://www.w3.org/1998/Math/MathML"><msubsup><mrow class="MJX-TeXAtom-ORD"><mover><mi>χ<!-- χ --></mi><mo accent="false">¯<!-- ¯ --></mo></mover></mrow><mn>1</mn><mn>0</mn></msubsup></math> masses below 30 GeV. For a branching fraction of 50% to either <math xmlns="http://www.w3.org/1998/Math/MathML"><mover><mi>t</mi><mo accent="false">¯<!-- ¯ --></mo></mover><mtext> </mtext><mo stretchy="false">→<!-- → --></mo><mi>t</mi><msubsup><mrow class="MJX-TeXAtom-ORD"><mover><mi>χ<!-- χ --></mi><mo accent="false">¯<!-- ¯ --></mo></mover></mrow><mn>1</mn><mn>0</mn></msubsup></math> or <math xmlns="http://www.w3.org/1998/Math/MathML"><mover><mi>t</mi><mo accent="false">¯<!-- ¯ --></mo></mover><mtext> </mtext><mo stretchy="false">→<!-- → --></mo><mi>b</mi><msubsup><mrow class="MJX-TeXAtom-ORD"><mover><mi>χ<!-- χ --></mi><mo accent="false">¯<!-- ¯ --></mo></mover></mrow><mn>1</mn><mrow class="MJX-TeXAtom-ORD"><mo>±<!-- ± --></mo></mrow></msubsup></math>, and assuming the <math xmlns="http://www.w3.org/1998/Math/MathML"><msubsup><mrow class="MJX-TeXAtom-ORD"><mover><mi>&#x03C7;<!-- χ --></mi><mo accent="false">&#x00AF;<!-- ¯ --></mo></mover></mrow><mn>1</mn><mrow class="MJX-TeXAtom-ORD"><mo>&#x00B1;<!-- ± --></mo></mrow></msubsup></math> mass to be twice the <math xmlns="http://www.w3.org/1998/Math/MathML"><msubsup><mrow class="MJX-TeXAtom-ORD"><mover><mi>χ<!-- χ --></mi><mo accent="false">¯<!-- ¯ --></mo></mover></mrow><mn>1</mn><mn>0</mn></msubsup></math> mass, top squark masses in the range 250–550 GeV are excluded for<math xmlns="http://www.w3.org/1998/Math/MathML"><msubsup><mrow class="MJX-TeXAtom-ORD"><mover><mi>χ<!-- χ --></mi><mo accent="false">¯<!-- ¯ --></mo></mover></mrow><mn>1</mn><mn>0</mn></msubsup></math> masses below 60 GeV.
format Articulo
Articulo
author Alconada Verzini, María Josefina
Alonso, Francisco
Anduaga, Xabier Sebastián
Dova, María Teresa
Monticelli, Fernando Gabriel
Wahlberg, Hernán Pablo
The ATLAS Collaboration
author_facet Alconada Verzini, María Josefina
Alonso, Francisco
Anduaga, Xabier Sebastián
Dova, María Teresa
Monticelli, Fernando Gabriel
Wahlberg, Hernán Pablo
The ATLAS Collaboration
author_sort Alconada Verzini, María Josefina
title Search for direct pair production of the top squark in all-hadronic final states in proton-proton collisions at √s = 8 TeV with the ATLAS detector
title_short Search for direct pair production of the top squark in all-hadronic final states in proton-proton collisions at √s = 8 TeV with the ATLAS detector
title_full Search for direct pair production of the top squark in all-hadronic final states in proton-proton collisions at √s = 8 TeV with the ATLAS detector
title_fullStr Search for direct pair production of the top squark in all-hadronic final states in proton-proton collisions at √s = 8 TeV with the ATLAS detector
title_full_unstemmed Search for direct pair production of the top squark in all-hadronic final states in proton-proton collisions at √s = 8 TeV with the ATLAS detector
title_sort search for direct pair production of the top squark in all-hadronic final states in proton-proton collisions at √s = 8 tev with the atlas detector
publishDate 2014
url http://sedici.unlp.edu.ar/handle/10915/79010
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AT alonsofrancisco searchfordirectpairproductionofthetopsquarkinallhadronicfinalstatesinprotonprotoncollisionsats8tevwiththeatlasdetector
AT anduagaxabiersebastian searchfordirectpairproductionofthetopsquarkinallhadronicfinalstatesinprotonprotoncollisionsats8tevwiththeatlasdetector
AT dovamariateresa searchfordirectpairproductionofthetopsquarkinallhadronicfinalstatesinprotonprotoncollisionsats8tevwiththeatlasdetector
AT monticellifernandogabriel searchfordirectpairproductionofthetopsquarkinallhadronicfinalstatesinprotonprotoncollisionsats8tevwiththeatlasdetector
AT wahlberghernanpablo searchfordirectpairproductionofthetopsquarkinallhadronicfinalstatesinprotonprotoncollisionsats8tevwiththeatlasdetector
AT theatlascollaboration searchfordirectpairproductionofthetopsquarkinallhadronicfinalstatesinprotonprotoncollisionsats8tevwiththeatlasdetector
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spelling I19-R120-10915-790102020-05-22T04:07:32Z http://sedici.unlp.edu.ar/handle/10915/79010 issn:1029-8479 Search for direct pair production of the top squark in all-hadronic final states in proton-proton collisions at √s = 8 TeV with the ATLAS detector Alconada Verzini, María Josefina Alonso, Francisco Anduaga, Xabier Sebastián Dova, María Teresa Monticelli, Fernando Gabriel Wahlberg, Hernán Pablo The ATLAS Collaboration 2014-09-01 2019-08-13T16:34:19Z en Ciencias Exactas Física hadron-hadron scattering supersymmetry top squark proton-proton scattering The results of a search for direct pair production of the scalar partner to the top quark using an integrated luminosity of 20.1 fb−1 of proton-proton collision data at √s = 8 TeV recorded with the ATLAS detector at the LHC are reported. The top squark is assumed to decay via <math xmlns="http://www.w3.org/1998/Math/MathML"><mover><mi>t</mi><mo accent="false">¯<!-- ¯ --></mo></mover><mtext> </mtext><mo stretchy="false">→<!-- → --></mo><mi>t</mi><msubsup><mrow class="MJX-TeXAtom-ORD"><mover><mi>χ<!-- χ --></mi><mo accent="false">¯<!-- ¯ --></mo></mover></mrow><mn>1</mn><mn>0</mn></msubsup></math> or <math xmlns="http://www.w3.org/1998/Math/MathML"><mover><mi>t</mi><mo accent="false">¯<!-- ¯ --></mo></mover><mtext> </mtext><mo stretchy="false">→<!-- → --></mo><mi>b</mi><msubsup><mrow class="MJX-TeXAtom-ORD"><mover><mi>χ<!-- χ --></mi><mo accent="false">¯<!-- ¯ --></mo></mover></mrow><mn>1</mn><mrow class="MJX-TeXAtom-ORD"><mo>±<!-- ± --></mo></mrow></msubsup><mtext> </mtext><mo stretchy="false">→<!-- → --></mo><mi>b</mi><msup><mrow class="MJX-TeXAtom-ORD"><mi>W</mi></mrow><mrow class="MJX-TeXAtom-ORD"><mrow><mo>(</mo><mo>∗<!-- ∗ --></mo><mo>)</mo></mrow></mrow></msup><msubsup><mrow class="MJX-TeXAtom-ORD"><mover><mi>χ<!-- χ --></mi><mo accent="false">¯<!-- ¯ --></mo></mover></mrow><mn>1</mn><mn>0</mn></msubsup></math>, where <math xmlns="http://www.w3.org/1998/Math/MathML"><msubsup><mrow class="MJX-TeXAtom-ORD"><mover><mi>χ<!-- χ --></mi><mo accent="false">¯<!-- ¯ --></mo></mover></mrow><mn>1</mn><mn>0</mn></msubsup><mtext> </mtext><mrow><mo>(</mo><msubsup><mrow class="MJX-TeXAtom-ORD"><mover><mi>χ<!-- χ --></mi><mo accent="false">¯<!-- ¯ --></mo></mover></mrow><mn>1</mn><mrow class="MJX-TeXAtom-ORD"><mo>±<!-- ± --></mo></mrow></msubsup><mo>)</mo></mrow></math> denotes the lightest neutralino (chargino) in supersymmetric models. The search targets a fullyhadronic final state in events with four or more jets and large missing transverse momentum. No significant excess over the Standard Model background prediction is observed, and exclusion limits are reported in terms of the top squark and neutralino masses and as a function of the branching fraction of <math xmlns="http://www.w3.org/1998/Math/MathML"><mover><mi>t</mi><mo accent="false">¯<!-- ¯ --></mo></mover><mtext> </mtext><mo stretchy="false">→<!-- → --></mo><mi>t</mi><msubsup><mrow class="MJX-TeXAtom-ORD"><mover><mi>χ<!-- χ --></mi><mo accent="false">¯<!-- ¯ --></mo></mover></mrow><mn>1</mn><mn>0</mn></msubsup></math>. For a branching fraction of 100%, top squark masses in the range 270–645 GeV are excluded for <math xmlns="http://www.w3.org/1998/Math/MathML"><msubsup><mrow class="MJX-TeXAtom-ORD"><mover><mi>χ<!-- χ --></mi><mo accent="false">¯<!-- ¯ --></mo></mover></mrow><mn>1</mn><mn>0</mn></msubsup></math> masses below 30 GeV. For a branching fraction of 50% to either <math xmlns="http://www.w3.org/1998/Math/MathML"><mover><mi>t</mi><mo accent="false">¯<!-- ¯ --></mo></mover><mtext> </mtext><mo stretchy="false">→<!-- → --></mo><mi>t</mi><msubsup><mrow class="MJX-TeXAtom-ORD"><mover><mi>χ<!-- χ --></mi><mo accent="false">¯<!-- ¯ --></mo></mover></mrow><mn>1</mn><mn>0</mn></msubsup></math> or <math xmlns="http://www.w3.org/1998/Math/MathML"><mover><mi>t</mi><mo accent="false">¯<!-- ¯ --></mo></mover><mtext> </mtext><mo stretchy="false">→<!-- → --></mo><mi>b</mi><msubsup><mrow class="MJX-TeXAtom-ORD"><mover><mi>χ<!-- χ --></mi><mo accent="false">¯<!-- ¯ --></mo></mover></mrow><mn>1</mn><mrow class="MJX-TeXAtom-ORD"><mo>±<!-- ± --></mo></mrow></msubsup></math>, and assuming the <math xmlns="http://www.w3.org/1998/Math/MathML"><msubsup><mrow class="MJX-TeXAtom-ORD"><mover><mi>&#x03C7;<!-- χ --></mi><mo accent="false">&#x00AF;<!-- ¯ --></mo></mover></mrow><mn>1</mn><mrow class="MJX-TeXAtom-ORD"><mo>&#x00B1;<!-- ± --></mo></mrow></msubsup></math> mass to be twice the <math xmlns="http://www.w3.org/1998/Math/MathML"><msubsup><mrow class="MJX-TeXAtom-ORD"><mover><mi>χ<!-- χ --></mi><mo accent="false">¯<!-- ¯ --></mo></mover></mrow><mn>1</mn><mn>0</mn></msubsup></math> mass, top squark masses in the range 250–550 GeV are excluded for<math xmlns="http://www.w3.org/1998/Math/MathML"><msubsup><mrow class="MJX-TeXAtom-ORD"><mover><mi>χ<!-- χ --></mi><mo accent="false">¯<!-- ¯ --></mo></mover></mrow><mn>1</mn><mn>0</mn></msubsup></math> masses below 60 GeV. Facultad de Ciencias Exactas Articulo Articulo http://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International (CC BY 4.0) application/pdf