skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Neutrinos in the simplest little Higgs scenario and TeV leptogenesis

Abstract

The little Higgs scenario may provide an interesting framework to accommodate TeV scale leptogenesis, because a TeV Majorana mass of the right-handed neutrino that we employ for the latter may find a natural place near the ultraviolet cutoff of the former. In this work we study how a light neutrino spectrum, generated radiatively, and TeV scale leptogenesis can be embedded in the simplest little Higgs framework. Alternatively, we highlight how the neutrino Yukawa textures of the latter are constrained.

Authors:
 [1];  [2];  [3]
  1. LPT, Universite de Paris-Sud XI, Batiment 210, 91405 Orsay Cedex (France)
  2. Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata 700064 (India)
  3. Centro de Investigaciones, Universidad Antonio Narino, Cll. 58A No. 37-94, Santa Fe de Bogota (Colombia)
Publication Date:
OSTI Identifier:
20776639
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 73; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevD.73.033006; (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; ENERGY SPECTRA; HIGGS BOSONS; HIGGS MODEL; NEUTRINOS; REST MASS; TEV RANGE; ULTRAVIOLET RADIATION

Citation Formats

Abada, Asmaa, Bhattacharyya, Gautam, and Losada, Marta. Neutrinos in the simplest little Higgs scenario and TeV leptogenesis. United States: N. p., 2006. Web. doi:10.1103/PhysRevD.73.033006.
Abada, Asmaa, Bhattacharyya, Gautam, & Losada, Marta. Neutrinos in the simplest little Higgs scenario and TeV leptogenesis. United States. doi:10.1103/PhysRevD.73.033006.
Abada, Asmaa, Bhattacharyya, Gautam, and Losada, Marta. Wed . "Neutrinos in the simplest little Higgs scenario and TeV leptogenesis". United States. doi:10.1103/PhysRevD.73.033006.
@article{osti_20776639,
title = {Neutrinos in the simplest little Higgs scenario and TeV leptogenesis},
author = {Abada, Asmaa and Bhattacharyya, Gautam and Losada, Marta},
abstractNote = {The little Higgs scenario may provide an interesting framework to accommodate TeV scale leptogenesis, because a TeV Majorana mass of the right-handed neutrino that we employ for the latter may find a natural place near the ultraviolet cutoff of the former. In this work we study how a light neutrino spectrum, generated radiatively, and TeV scale leptogenesis can be embedded in the simplest little Higgs framework. Alternatively, we highlight how the neutrino Yukawa textures of the latter are constrained.},
doi = {10.1103/PhysRevD.73.033006},
journal = {Physical Review. D, Particles Fields},
number = 3,
volume = 73,
place = {United States},
year = {Wed Feb 01 00:00:00 EST 2006},
month = {Wed Feb 01 00:00:00 EST 2006}
}
  • In the framework of the simplest little Higgs model, we perform a comprehensive study for the pair productions of the pseudoscalar boson {eta} and standard model-like Higgs boson h at LHC, namely gg(bb){yields}{eta}{eta}, gg(qq){yields}{eta}h, and gg(bb){yields}hh. These production processes provide a way to probe the couplings between Higgs bosons. We find that the cross section of gg{yields}{eta}{eta} always dominates over that of bb{yields}{eta}{eta}. When the Higgs boson h which mediates these two processes is on-shell, their cross sections can reach several thousand fb and several hundred fb, respectively. When the intermediate state h is off-shell, those two cross sections aremore » reduced by 2 orders of magnitude, respectively. The cross sections of gg{yields}{eta}h and qq{yields}{eta}h are about in the same order of magnitude, which can reach O(10{sup 2} fb) for a light {eta} boson. Besides, compared with the standard model prediction, the cross section of a pair of standard model-like Higgs bosons production at LHC can be enhanced sizably. Finally, we briefly discuss the observable signatures of {eta}{eta}, {eta}h, and hh at the LHC.« less
  • We present an ultraviolet extension of the 'simplest little Higgs' model. The model marries the simplest little Higgs at low energies to two copies of the 'littlest Higgs' at higher energies. The result is a weakly coupled theory below 100 TeV with a naturally light Higgs. The higher cutoff suppresses the contributions of strongly coupled dynamics to dangerous operators such as those which induce flavor changing neutral currents and CP violation. We briefly survey the distinctive phenomenology of the model.
  • The colored SU(2){sub L}-singlet heavy T-quark is one of the most crucial ingredients in little Higgs models, which is introduced to cancel the largest contribution of the standard model (SM) top quark to the Higgs boson mass at one-loop level. In two representative little Higgs models, the littlest Higgs model and the SU(3) simplest Higgs model, we comprehensively study the single heavy T-quark production at Large Hadron Collider (LHC). After presenting the possibility of relatively light ({approx}500 GeV) T-quark in the simplest little Higgs model, we consider all the relevant processes, the 2{yields}2 process of qb{yields}q{sup '}T, the 2{yields}3 processmore » of qg{yields}q{sup '}Tb, the s-channel process of qq{sup '}{yields}Tb, and the gluon-fusion process of gg{yields}Tt. We found that the 2{yields}3 process can be quite important, as its cross section is about 30% of the 2{yields}2 one and it is dominant in high p{sub T} distributions. The s-channel and the gluon-fusion processes also show distinctive features in spite of their suppressed cross sections. In the gluon-fusion process of the simplest little Higgs model, for example, the pseudoscalar contribution is rather dominant over the Higgs contribution for relatively light M{sub T}.« less
  • The SU(3) simplest little Higgs model in its original framework without the so-called {mu} term inevitably involves a massless pseudoscalar boson {eta}, which is problematic for b physics and the cosmological axion limit. With the {mu} term introduced by hand, the {eta} boson acquires mass m{sub {eta}}{approx}{mu}, which can be lighter than half the Higgs boson mass in a large portion of the parameter space. In addition, the introduced {mu} term generates sizable coupling of H-{eta}-{eta}. The Higgs boson can dominantly decay into a pair of {eta}'s especially when m{sub H} is below the WW threshold. Another new decay channelmore » of H{yields}Z{eta} can be dominant or compatible with H{yields}W{sup +}W{sup -} for m{sub H} above the Z{eta} threshold. We show that the LEP bound on the Higgs boson mass is loosened to some extent due to this new H{yields}{eta}{eta} decay channel as well as the reduced coupling of H-Z-Z. The Higgs boson mass bound falls to about 110 GeV for f=3-4 TeV. Since the {eta} boson decays mainly into a bb pair, H{yields}{eta}{eta}{yields}4b and H{yields}Z{eta}{yields}Zbb open up other interesting search channels in the pursuit of the Higgs boson in the future experiments. We discuss these issues.« less
  • We derive the leptonic neutral current in the simplest little Higgs model and compute the contribution of the model to the decay width Z{yields}e{sup +}e{sup -}. Using the precision electroweak data we obtain a strong lower bound f{>=}5.6 TeV at 95% C.L. on the characteristic energy scale of the model. It results in a lower bound for the new gauge bosons W{sup '{+-}} and Z{sup '} as being M{sub W{sup '{+-}}}{>=}2.6 TeV and M{sub Z{sup '}}{>=}3.1 TeV, respectively. We also present the allowed values of the k=f{sub 1}/f{sub 2} which is the parameter relating the two vacuum expectation values ofmore » the scalar triplets in the model, and the {mu} parameter of a quadratic term, involving the triplets, necessary to provide an acceptable mass range for the standard Higgs boson.« less