Proton stability and lightZ′inspired by string derived models
نویسندگان
چکیده
منابع مشابه
Proton stability in superstring derived models
I discuss the problem of proton decay, from dimension four, five and six operators, in superstring derived standard–like models. I classify the sectors that produce color triplet superfields which may generate proton decay from dimension five and six operators. I show that for two of these sectors there exist a unique superstring doublet–triplet splitting mechanism that projects out the color t...
متن کاملProton Stability in Leptoquark Models
We show that in generic leptoquark (LQ) extensions of the standard model lepton and baryon numbers are broken at the level of renormalizable operators. In particular, this may cause fast proton decay unless the leptoquarks are heavy enough. We derive stringent bounds for the 1st generation LQ masses and couplings from the proton stability constraints. Leptoquark models [1, 2] remain an attracti...
متن کاملLeft–Right Symmetric Heterotic–String Derived Models
Recently it was demonstrated that free fermionic heterotic–strings can produce models with solely the Minimal Supersymmetric Standard Model states in the low energy spectrum. This unprecedented result provides further strong evidence for the possibility that the true string vacuum shares some of the properties of the free fermionic models. Past free fermionic models have focused on several poss...
متن کاملAnomalous U (1)’s and Proton Stability in Brane Models
We consider the most general generation-independent U(1) gauge symmetry consistent with the presence of Yukawa couplings for all quarks and leptons in the SUSY version of the Standard Model. This U(1) has generically mixed anomalies with SM groups, which cannot be cancelled by the Green-Schwarz mechanism of heterotic D = 4 strings. We argue that these anomalies can in principle be cancelled by ...
متن کاملFlat Directions in Left–Right Symmetric String Derived Models
The only string models known to reproduce the Minimal Supersymmetric Standard Model in the low energy effective field theory are those constructed in the free fermionic formulation. We demonstrate the existence of quasi– realistic free fermionic heterotic–string models in which supersymmetric singlet flat directions do not exist. This raises the possibility that supersymmetry is broken perturba...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Physical Review D
سال: 2011
ISSN: 1550-7998,1550-2368
DOI: 10.1103/physrevd.84.086006