# An effective Higgsless theory: Satisfying electroweak constraints and a heavy top quark

## Abstract

The main challenge faced by Higgsless models of electroweak symmetry breaking is to reconcile the experimental constraints imposed by the precision electroweak data and the top quark phenomenology with the unitarity constraints imposed by longitudinal gauge boson scattering amplitudes. In this paper we expand on previous work, giving details of how delocalized fermions can be used to adjust the S parameter to zero, while keeping the T and U parameters naturally suppressed. We also show that it is possible to obtain the top quark mass, without affecting the delay of unitarity violation of the W{sup +}W{sup -}{yields}W{sup +}W{sup -} scattering amplitude, by separating the mass scales of the fermion sector (1/R{sub f}) from that of the gauge sector (1/R{sub g}). The fermion sector scale 1/R{sub f} is only weakly constrained by unitarity of the tt{yields}W{sup +}W{sup -} scattering amplitude; thus the ratio R{sub g}/R{sub f} can be quite large, and the top mass can be achieved easily. Anomalous right-handed couplings involving the third generation quarks also avoid constraints from experimental data if 1/R{sub f} is sufficiently large.

- Authors:

- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824 (United States)

- Publication Date:

- OSTI Identifier:
- 20782842

- Resource Type:
- Journal Article

- Resource Relation:
- Journal Name: Physical Review. D, Particles Fields; Journal Volume: 73; Journal Issue: 7; Other Information: DOI: 10.1103/PhysRevD.73.075011; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; COUPLING; REST MASS; SCATTERING AMPLITUDES; STANDARD MODEL; SYMMETRY BREAKING; T QUARKS; UNITARITY; W MINUS BOSONS; W PLUS BOSONS

### Citation Formats

```
Foadi, Roshan, and Schmidt, Carl.
```*An effective Higgsless theory: Satisfying electroweak constraints and a heavy top quark*. United States: N. p., 2006.
Web. doi:10.1103/PHYSREVD.73.075011.

```
Foadi, Roshan, & Schmidt, Carl.
```*An effective Higgsless theory: Satisfying electroweak constraints and a heavy top quark*. United States. doi:10.1103/PHYSREVD.73.075011.

```
Foadi, Roshan, and Schmidt, Carl. Sat .
"An effective Higgsless theory: Satisfying electroweak constraints and a heavy top quark". United States.
doi:10.1103/PHYSREVD.73.075011.
```

```
@article{osti_20782842,
```

title = {An effective Higgsless theory: Satisfying electroweak constraints and a heavy top quark},

author = {Foadi, Roshan and Schmidt, Carl},

abstractNote = {The main challenge faced by Higgsless models of electroweak symmetry breaking is to reconcile the experimental constraints imposed by the precision electroweak data and the top quark phenomenology with the unitarity constraints imposed by longitudinal gauge boson scattering amplitudes. In this paper we expand on previous work, giving details of how delocalized fermions can be used to adjust the S parameter to zero, while keeping the T and U parameters naturally suppressed. We also show that it is possible to obtain the top quark mass, without affecting the delay of unitarity violation of the W{sup +}W{sup -}{yields}W{sup +}W{sup -} scattering amplitude, by separating the mass scales of the fermion sector (1/R{sub f}) from that of the gauge sector (1/R{sub g}). The fermion sector scale 1/R{sub f} is only weakly constrained by unitarity of the tt{yields}W{sup +}W{sup -} scattering amplitude; thus the ratio R{sub g}/R{sub f} can be quite large, and the top mass can be achieved easily. Anomalous right-handed couplings involving the third generation quarks also avoid constraints from experimental data if 1/R{sub f} is sufficiently large.},

doi = {10.1103/PHYSREVD.73.075011},

journal = {Physical Review. D, Particles Fields},

number = 7,

volume = 73,

place = {United States},

year = {Sat Apr 01 00:00:00 EST 2006},

month = {Sat Apr 01 00:00:00 EST 2006}

}