相关论文: Exotic Fermions
We investigate the mixing of an extra ${Z^0}^\prime$ with the standard $Z^0$ and mixings of exotic fermions with their standard counterparts through some precisely measured electroweak observables. These observables are geared to search for…
The constraints on the mixing angles of the standard fermions with new heavy particles that can appear in many extensions of the electroweak theory are reviewed. Some emphasis is put in distinguishing the effects of a mixing with new states…
In this talk I summarize the status of exotic mesons, including both theoretical expectations and experimental candidates. The current experimental candidates are ``spin-parity exotics''; since these are most often considered possible…
We employ data from precision electroweak tests and collider searches to derive constraints on the possibility that weak-singlet fermions mix with the ordinary Standard Model fermions. Our findings are presented within the context of a…
The extension of the Standard Model with exotic quark singlets and doublets introduces large flavor changing neutral couplings between ordinary fermions. We derive inequalities which translate the precise determination of the diagonal Z…
This invited contribution summarizes some of the more important aspects of exotics. We review theoretical expectations for exotic and nonexotic hybrid mesons, and briefly discuss the leading experimental candidate for an exotic, the…
Exotic interactions between fermions mediated by new bosons beyond the Standard Model may hold the key to several fundamental conundrums on the frontier of physics.However, laboratory searching for exotic interactions on small length scales…
The spectral properties of hybrid meson interpolating fields are investigated. The quantum numbers of the meson are carried by smeared-source fermion operators and highly-improved chromo-electric and -magnetic field operators composed with…
We show that, contrary to common expectations, the observed charged leptons can have a substantial mixing with new heavier fermions, at the level of 20$\%$. This can happen, in the language of effective theories, when the effect of mixing…
We study the effects induced by new neutral fermions below their mass threshold, due to their possible mixing with the standard neutrinos. We use as experimental constraints the recent results on lepton universality, together with the…
The new contributions to the electron (muon) anomalous magnetic moment arising in mirror fermion theories have been calculated. Imposing the experimental constraint lowers the current upper bound on the ordinary - mirror lepton mixing…
With the strong experimental evidence for standard neutrino mass and mixings, there exists now a possibility of the lepton flavor violating process e\sup + mu \sup - \arrow W \sup + W \sup -, which would occur via t-channel neutrino…
We investigate the consequences of introducing a set of exotic doublet leptons which couple to the standard model leptons in a minimal way. Through these additional gauge invariant and renormalizable coupling terms, new sources of…
Exotic spin-dependent interactions between fermions have recently attracted attention in relation to theories beyond the Standard Model. The exotic interactions can be mediated by hypothetical fundamental bosons which may explain several…
A topological interpretation of the electron--electron interaction under FQHE conditions gives rise to the existence of some kind of composite fermions. The interaction term is similar to the Coulomb interaction and produces punctures in…
The possibility of additional quarks and leptons beyond the three generations already established is discussed. The make-up of this Report is (I) Introduction: the motivations for believing that the present litany of elementary fermions is…
Preliminary results of measurements of fermion-pair production at LEP2 are used to derive limits on new physics phenomena. Combinations of the cross sections and asymmetrie of the 4 LEP collaborations are interpreted in terms four-fermion…
We investigate the status of models containing exotic fermions or extra Z-like neutral gauge bosons in the light of the recent data on anomalous magnetic moment of muon. We find that it is possible to extract interesting bounds on the…
A system of exclusive fermions occurs when two fermions of opposite spin are prohibited from occupying the same quantum level. We derive the distribution of exclusive fermions via the employment of the grand canonical ensemble. Salient…
We investigate the experimentally allowed parameter space of an extension of the standard model (SM3) by one additional family of fermions. Therefore we extend our previous study of the CKM like mixing constraints of a fourth generation of…