Less space for a new family of fermions

@article{Eberhardt2010LessSF,
  title={Less space for a new family of fermions},
  author={O. Eberhardt and A. Lenz and J. Rohrwild},
  journal={Physical Review D},
  year={2010},
  volume={82},
  pages={095006}
}
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 Cabibbo-Kobayashi-Maskawa (CKM)-like mixing constraints of a fourth generation of quarks. In addition to the bounds from tree-level determinations of the 3x3 CKM elements and flavor-changing neutral currents processes (K, D, B{sub d}, B{sub s} mixing and the decay b{yields}s{gamma}) we also investigate the… Expand

Figures and Tables from this paper

Patterns of flavour violation in the presence of a fourth generation of quarks and leptons
We calculate a number of observables related to particle-antiparticle mixing and the branching ratios for the most interesting rare and CP-violating K and B decays in the Standard Model (SM3)Expand
Higgs Properties in the Fourth Generation MSSM: Boosted Signals Over the 3G Plan
The generalization of the MSSM to the case of four chiral fermion generations (4GMSSM) can lead to significant changes in the phenomenology of the otherwise familiar Higgs sector. In most of theExpand
Closing in on a perturbative fourth generation
A bstractA perturbative new family of fermions is now severely constrained, though not excluded yet. We reconsider the current bounds (i.e., direct and from Higgs searches, Rb, oblique parameters) onExpand
An A5 model of four lepton generations
We study the lepton sector of a four generations model based on the discrete flavor group A5. The best features of the three family A4 model survive, including the tribimaximal pattern of threeExpand
Like-sign dimuon charge asymmetry in the Randall-Sundrum model
We confirm that in order to account for the recent D0 result of large like-sign dimuon charge asymmetry, a considerable large new physics effect in {Gamma}{sub 12}{sup s} is required in addition to aExpand
Updated status of the global electroweak fit and constraints on new physics
We present an update of the Standard Model fit to electroweak precision data. We include newest experimental results on the top-quark mass, the W mass and width, and the Higgs-boson mass bounds fromExpand
Muon g-2 and lepton flavor violation in a two Higgs doublets model for the fourth generation
Abstract In the minimal Standard Model (SM) with four generations (the so-called SM4) and in “standard” two Higgs doublets model (2HDM) setups, e.g., the type II 2HDM with four fermion generations,Expand
Z-mediated charge and CP asymmetries and FCNCs in Bd,s processes
We show model-independently that the negative like-sign charge asymmetry (−Asℓb) is less than 3.16 × 10−3 when the constraints from the $ {B_q} - {\bar{B}_q} $ mixings and the time-dependent CPExpand
Implications of large dimuon CP asymmetry in Bd,s decays on minimal flavor violation with low tan β
The D0 collaboration has recently announced evidence for a dimuon CP asymmetry in Bd,s decays of order one percent. If confirmed, this asymmetry requires new physics. We argue that for minimallyExpand
On new physics in ΔΓd
A bstractMotivated by the recent measurement of the dimuon asymmetry by the DØ collaboration, which could be interpreted as an enhanced decay rate difference in the neutral Bd-meson system, weExpand
...
1
2
3
4
5
...

References

SHOWING 1-10 OF 145 REFERENCES
How much space is left for a new family of fermions
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 determinationsExpand
Patterns of flavour violation in the presence of a fourth generation of quarks and leptons
We calculate a number of observables related to particle-antiparticle mixing and the branching ratios for the most interesting rare and CP-violating K and B decays in the Standard Model (SM3)Expand
Standard model with four generations: Selected implications for rare B and K decays
We extend our recent work and study implications of the standard model with four generations (SM4) for rare B and K decays. We again take seriously the several 2-3{sigma} anomalies seen in B, B{subExpand
Phenomenological Constraints on Extended Quark Sectors
We study the flavor physics in two extensions of the quark sector of the Standard Model (SM): a four generation model and a model with a single vector--like down--type quark (VDQ). In our analysis weExpand
NONSUPERSYMMETRIC SU(5) RESUSCITATED BY NEW QUARKS AND LEPTONS
The issue of gauge unification in the (nonsupersymmetric) standard model is reinvestigated. It is found that, with just an additional fourth generation of quarks and leptons, SU(3){circle_times}SU(2)Expand
Extra families, Higgs spectrum, and oblique corrections
The standard model accommodates, but does not explain, three families of leptons and quarks, while various extensions suggest extra matter families. The oblique corrections from extra chiral familiesExpand
Implications of D0- ¯D0 Mixing for New Physics
We provide a comprehensive, up-to-date analysis of possible New Physics contributions to the mass difference ∆MD in D 0-D 0 mixing. We consider the most general low energy effective Hamiltonian andExpand
Experimental constraints on fourth generation quark masses
The existing bounds from CDF on the masses of the fourth generation quarks, t{sup '} and b{sup '}, are reexamined. The bound of 256 GeV on the t{sup '} mass assumes that the primary decay of theExpand
Simultaneous extraction of the Fermi constant and PMNS matrix elements in the presence of a fourth generation
Several recent studies performed on constraints of a fourth generation of quarks and leptons suffer from the ad-hoc assumption that 3 × 3 unitarity holds for the first three generations in theExpand
The impact of a 4th generation on mixing and CP violation in the charm system
We study $$ {D^0} - {\overline D^0} $$ mixing in the presence of a fourth generation of quarks. In particular, we calculate the size of the allowed CP violation which is found at the observable levelExpand
...
1
2
3
4
5
...