Publication
Combined search for the quarks of a sequential fourth generation
| dc.contributor.author | CMS collaboration (2202 authors) | |
| dc.contributor.author | Hollar, Jonathan | |
| dc.contributor.author | Nayak, Aruna | |
| dc.contributor.author | Almeida, Nuno | |
| dc.contributor.author | Bargassa, Pedrame | |
| dc.contributor.author | David Tinoco Mendes, Andre | |
| dc.contributor.author | Faccioli, Pietro | |
| dc.contributor.author | Ferreira Parracho, Pedro Guilherme | |
| dc.contributor.author | Gallinaro, Michele | |
| dc.contributor.author | Seixas, Joao | |
| dc.contributor.author | Varela, Joao | |
| dc.contributor.author | Vischia, Pietro | |
| dc.contributor.author | Lloret Iglesias, Lara | |
| dc.contributor.author | Musella, Pasquale | |
| dc.contributor.author | Rodrigues Antunes, Joao | |
| dc.contributor.author | Silva, Pedro | |
| dc.contributor.author | Pela, Joao | |
| dc.contributor.author | Leonardo, Nuno | |
| dc.date.accessioned | 2019-02-03T21:00:10Z | |
| dc.date.available | 2019-02-03T21:00:10Z | |
| dc.date.issued | 2012-09 | |
| dc.date.updated | 2019-02-03T21:00:10Z | |
| dc.description.abstract | 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 5 inverse femtobarns 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 685 GeV is excluded at 95% confidence level for minimal off-diagonal mixing between the third- and the fourth-generation quarks. With a mass difference of 25 GeV between the quark masses, the obtained limit on the masses of the fourth-generation quarks shifts by about +/- 20 GeV. These results significantly reduce the allowed parameter space for a fourth generation of fermions. | |
| dc.description.version | Peer Reviewed | |
| dc.identifier | Phys.Rev. D86 (2012) 112003; DOI 10.1103/PhysRevD.86.112003 | |
| dc.identifier.uri | http://dx.doi.org/10.1103/PhysRevD.86.112003 | |
| dc.identifier.uri | http://hdl.handle.net/10400.26/26261 | |
| dc.language.iso | eng | |
| dc.title | Combined search for the quarks of a sequential fourth generation | |
| dc.type | journal article | |
| dspace.entity.type | Publication | |
| rcaap.rights | openAccess | pt |
| rcaap.type | article |