How much space is left for a new family of fermions?

Autor:	Juergen Rohrwild, Alexander Lenz, Johann Riedl, Markus Bobrowski
Rok vydání:	2009
Předmět:	Quantum chromodynamics Quark Physics Nuclear and High Energy Physics Particle physics Particle decay Neutral current Unitarity Cabibbo–Kobayashi–Maskawa matrix High Energy Physics::Phenomenology High Energy Physics::Experiment Fermion Mixing (physics)
Zdroj:	Physical Review D. 79
ISSN:	1550-2368 1550-7998
DOI:	10.1103/physrevd.79.113006
Popis:	We perform an exploratory study of the allowed parameter range for the CKM-like mixing of hypothetical quarks of a fourth generation. As experimental constraints we use the tree-level determinations of the 3x3 Cabibbo-Kobayashi-Maskawa (CKM) elements and flavor-changing neutral current (FCNC) processes (K, D, B{sub d}, B{sub s} mixing and the decay b{yields}s{gamma}) under the assumption that the 4x4 CKM matrix is unitary. For the FCNCs we use some simplifying assumptions concerning the QCD corrections. Typically small mixing with the fourth family is favored; contrary to expectation, however, we find that also a quite large mixing with the fourth family is not yet excluded.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::b15adf1a9e381dd821914ff1a648b81b https://doi.org/10.1103/physrevd.79.113006 Zobrazit plný text záznamu