Combined search for the quarks of a sequential fourth generation
Results are presented from a search for a fourth generation of quarks produced singly or in pairs in a data set corresponding to an integrated luminosity of 5fb-1 recorded by the CMS experiment at the LHC in 2011. A novel strategy has been developed for a combined search for quarks of the up and dow...
| Main Authors: | , , , , , , , , , , , , , , , , , , , , , , , , |
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| Format: | Journal article |
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2012
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| _version_ | 1826279009332232192 |
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| author | Chatrchyan, S Khachatryan, V Sirunyan, A Tumasyan, A Adam, W Aguilo, E Bergauer, T Dragicevic, M Eroe, J Fabjan, C Friedl, M Fruehwirth, R Ghete, V Hammer, J Hoermann, N Hrubec, J Jeitler, M Kiesenhofer, W Knuenz, V Krammer, M Kraetschmer, I Liko, D Mikulec, I Pernicka, M Rahbaran, B |
| author_facet | Chatrchyan, S Khachatryan, V Sirunyan, A Tumasyan, A Adam, W Aguilo, E Bergauer, T Dragicevic, M Eroe, J Fabjan, C Friedl, M Fruehwirth, R Ghete, V Hammer, J Hoermann, N Hrubec, J Jeitler, M Kiesenhofer, W Knuenz, V Krammer, M Kraetschmer, I Liko, D Mikulec, I Pernicka, M Rahbaran, B |
| author_sort | Chatrchyan, S |
| collection | OXFORD |
| description | Results are presented from a search for a fourth generation of quarks produced singly or in pairs in a data set corresponding to an integrated luminosity of 5fb-1 recorded by the CMS experiment at the LHC in 2011. A novel strategy has been developed for a combined search for quarks of the up and down type in decay channels with at least one isolated muon or electron. Limits on the mass of the fourth-generation quarks and the relevant Cabibbo-Kobayashi-Maskawa matrix elements are derived in the context of a simple extension of the standard model with a sequential fourth generation of fermions. The existence of mass-degenerate fourth-generation quarks with masses below 685GeV is excluded at 95% confidence level for minimal off-diagonal mixing between the third- and the fourth-generation quarks. With a mass difference of 25GeV between the quark masses, the obtained limit on the masses of the fourth-generation quarks shifts by about ±20GeV. These results significantly reduce the allowed parameter space for a fourth generation of fermions. © 2012 CERN. |
| first_indexed | 2024-03-06T23:52:26Z |
| format | Journal article |
| id | oxford-uuid:7310aef3-8b36-4a3d-821e-704f68df4828 |
| institution | University of Oxford |
| last_indexed | 2024-03-06T23:52:26Z |
| publishDate | 2012 |
| record_format | dspace |
| spelling | oxford-uuid:7310aef3-8b36-4a3d-821e-704f68df48282022-03-26T19:54:06ZCombined search for the quarks of a sequential fourth generationJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:7310aef3-8b36-4a3d-821e-704f68df4828Symplectic Elements at Oxford2012Chatrchyan, SKhachatryan, VSirunyan, ATumasyan, AAdam, WAguilo, EBergauer, TDragicevic, MEroe, JFabjan, CFriedl, MFruehwirth, RGhete, VHammer, JHoermann, NHrubec, JJeitler, MKiesenhofer, WKnuenz, VKrammer, MKraetschmer, ILiko, DMikulec, IPernicka, MRahbaran, BResults are presented from a search for a fourth generation of quarks produced singly or in pairs in a data set corresponding to an integrated luminosity of 5fb-1 recorded by the CMS experiment at the LHC in 2011. A novel strategy has been developed for a combined search for quarks of the up and down type in decay channels with at least one isolated muon or electron. Limits on the mass of the fourth-generation quarks and the relevant Cabibbo-Kobayashi-Maskawa matrix elements are derived in the context of a simple extension of the standard model with a sequential fourth generation of fermions. The existence of mass-degenerate fourth-generation quarks with masses below 685GeV is excluded at 95% confidence level for minimal off-diagonal mixing between the third- and the fourth-generation quarks. With a mass difference of 25GeV between the quark masses, the obtained limit on the masses of the fourth-generation quarks shifts by about ±20GeV. These results significantly reduce the allowed parameter space for a fourth generation of fermions. © 2012 CERN. |
| spellingShingle | Chatrchyan, S Khachatryan, V Sirunyan, A Tumasyan, A Adam, W Aguilo, E Bergauer, T Dragicevic, M Eroe, J Fabjan, C Friedl, M Fruehwirth, R Ghete, V Hammer, J Hoermann, N Hrubec, J Jeitler, M Kiesenhofer, W Knuenz, V Krammer, M Kraetschmer, I Liko, D Mikulec, I Pernicka, M Rahbaran, B Combined search for the quarks of a sequential fourth generation |
| title | Combined search for the quarks of a sequential fourth generation |
| title_full | Combined search for the quarks of a sequential fourth generation |
| title_fullStr | Combined search for the quarks of a sequential fourth generation |
| title_full_unstemmed | Combined search for the quarks of a sequential fourth generation |
| title_short | Combined search for the quarks of a sequential fourth generation |
| title_sort | combined search for the quarks of a sequential fourth generation |
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