Constraints on Left-Right Symmetric and $E_6$ Superstring Models from the Number of Light Neutrino Species
| dc.creator | Gutierrez-Rodriguez, A. | |
| dc.creator | Hernandez-Ruiz, M. A. | |
| dc.creator | Perez, M. A. | |
| dc.creator | Perez-Vargas, F. | |
| dc.date | 2008-06-12 | |
| dc.date.accessioned | 2026-07-07T12:39:06Z | |
| dc.date.available | 2026-07-07T12:39:06Z | |
| dc.description | Using the experimental value for the rate $R^{LEP} _{exp}=Γ_{inv}/Γ_{l\bar l}=5.942\pm 0.016$, we derive constraints on the number of light neutrino species with the invisible width method in the framework of a left-right symmetric model (LRSM) and a $E_6$ superstring model as a function of their respective mixing angles for the neutral vector gauge bosons. Using the above LEP result we get the constraints $-1.6\times 10^{-3}\leqϕ\leq 1.1\times 10^{-3}$ and $-1.3\times 10^{-2}\leqϕ_{E_6} \leq 0.4\times 10^{-2}$, which are stronger than those obtained in previous studies of these models. | |
| dc.description | 9 pages, 4 figures, Submit to Modern Physics Letter A | |
| dc.identifier | https://arxiv.org/abs/0806.2163 | |
| dc.identifier | http://arxiv.org/abs/0806.2163 | |
| dc.identifier | Mod.Phys.Lett.A24:135-141,2009 | |
| dc.identifier | doi:10.1142/S0217732309027431 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/218991 | |
| dc.subject | High Energy Physics - Phenomenology | |
| dc.title | Constraints on Left-Right Symmetric and $E_6$ Superstring Models from the Number of Light Neutrino Species | |
| dc.type | text |