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Title: Vacuum stability and naturalness in type-II seesaw

Abstract

Here, we study the vacuum stability and perturbativity conditions in the minimal type-II seesaw model. These conditions give characteristic constraints to the model parameters. In the model, there is a SU(2) L triplet scalar field, which could cause a large Higgs mass correction. From the naturalness point of view, heavy Higgs masses should be lower than 350GeV, which may be testable by the LHC Run-II results. Due to the effects of the triplet scalar field, the branching ratios of the Higgs decay (h → γγ,Zγ) deviate from the standard model, and a large parameter region is excluded by the recent ATLAS and CMS combined analysis of h → γγ. Our result of the signal strength for h → γγ is R γγ ≲ 1.1, but its deviation is too small to observe at the LHC experiment.

Authors:
 [1];  [1];  [2]; ORCiD logo [3]
  1. Shimane Univ., Matsue (Japan)
  2. Univ. of Alabama, Tuscaloosa, AL (United States)
  3. Shimane Univ., Matsue (Japan); Hokkaido Univ., Sapporo (Japan)
Publication Date:
Research Org.:
Univ. of Alabama, Tuscaloosa, AL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
OSTI Identifier:
1257502
Grant/Contract Number:
SC0013680
Resource Type:
Journal Article: Published Article
Journal Name:
European Physical Journal. C, Particles and Fields
Additional Journal Information:
Journal Volume: 76; Journal Issue: 6; Journal ID: ISSN 1434-6044
Publisher:
Springer
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS

Citation Formats

Haba, Naoyuki, Ishida, Hiroyuki, Okada, Nobuchika, and Yamaguchi, Yuya. Vacuum stability and naturalness in type-II seesaw. United States: N. p., 2016. Web. doi:10.1140/epjc/s10052-016-4180-z.
Haba, Naoyuki, Ishida, Hiroyuki, Okada, Nobuchika, & Yamaguchi, Yuya. Vacuum stability and naturalness in type-II seesaw. United States. doi:10.1140/epjc/s10052-016-4180-z.
Haba, Naoyuki, Ishida, Hiroyuki, Okada, Nobuchika, and Yamaguchi, Yuya. 2016. "Vacuum stability and naturalness in type-II seesaw". United States. doi:10.1140/epjc/s10052-016-4180-z.
@article{osti_1257502,
title = {Vacuum stability and naturalness in type-II seesaw},
author = {Haba, Naoyuki and Ishida, Hiroyuki and Okada, Nobuchika and Yamaguchi, Yuya},
abstractNote = {Here, we study the vacuum stability and perturbativity conditions in the minimal type-II seesaw model. These conditions give characteristic constraints to the model parameters. In the model, there is a SU(2)L triplet scalar field, which could cause a large Higgs mass correction. From the naturalness point of view, heavy Higgs masses should be lower than 350GeV, which may be testable by the LHC Run-II results. Due to the effects of the triplet scalar field, the branching ratios of the Higgs decay (h → γγ,Zγ) deviate from the standard model, and a large parameter region is excluded by the recent ATLAS and CMS combined analysis of h → γγ. Our result of the signal strength for h → γγ is Rγγ ≲ 1.1, but its deviation is too small to observe at the LHC experiment.},
doi = {10.1140/epjc/s10052-016-4180-z},
journal = {European Physical Journal. C, Particles and Fields},
number = 6,
volume = 76,
place = {United States},
year = 2016,
month = 6
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1140/epjc/s10052-016-4180-z

Citation Metrics:
Cited by: 7works
Citation information provided by
Web of Science

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  • Here, we study the vacuum stability and perturbativity conditions in the minimal type-II seesaw model. These conditions give characteristic constraints to the model parameters. In the model, there is a SU(2) L triplet scalar field, which could cause a large Higgs mass correction. From the naturalness point of view, heavy Higgs masses should be lower than 350GeV, which may be testable by the LHC Run-II results. Due to the effects of the triplet scalar field, the branching ratios of the Higgs decay (h → γγ,Zγ) deviate from the standard model, and a large parameter region is excluded by the recentmore » ATLAS and CMS combined analysis of h → γγ. Our result of the signal strength for h → γγ is R γγ ≲ 1.1, but its deviation is too small to observe at the LHC experiment.« less
  • We study the vacuum stability and perturbativity conditions in the minimal type-II seesaw model. These conditions give characteristic constraints to the model parameters. In the model, there is a SU(2)L triplet scalar field, which could cause a large Higgs mass correction. From the natural- ness point of view, heavy Higgs masses should be lower than 350 GeV, which may be testable by the LHC Run-II results. Due to the effects of the triplet scalar field, the branching ratios of the Higgs decay (h → γγ, Zγ) deviate from the standard model, and a large parameter region is excluded by themore » recent ATLAS and CMS combined analysis of h → γ γ . Our result of the signal strength for h → γγ is Rγγ < 1.1, but its deviation is too small to observe at the LHC experiment.« less
  • The seesaw mechanism is conceived on the basis that a mass scale, {xi}, and a dimensionless scale, s, can be fine-tuned in order to control the dynamics of active and sterile neutrinos through cosmon-type equations of motion: the seesaw cosmon equations. This allows for sterile neutrinos to be a dark matter candidate. In this scenario, the dynamical masses and energy densities of active and sterile neutrinos can be consistently embedded into the generalized Chaplygin gas (GCG), the unified dark sector model. In addition, dark matter adiabatically coupled to dark energy allows for a natural decoupling of the (active) mass varyingmore » neutrino component from the dark sector. Thus mass varying neutrinos turn into a secondary effect. Through the scale parameters, {xi} and s, the proposed scenario allows for a convergence among three distinct frameworks: the cosmon scenario, the seesaw mechanism for mass generation, and the GCG model. It is found that the equation of state of the perturbations is the very one of the GCG background cosmology so that all the results from this approach are maintained, being smoothly modified by active neutrinos. Constrained by the seesaw relations, it is shown that the mass varying mechanism is responsible for the stability against linear perturbations and is indirectly related to the late time cosmological acceleration.« less
  • We generalize the Randall Sundrum warped braneworld model in six and higher dimension and propose a resolution to the mass hierarchy among the standard model fermions. The fine tuning problem in connection with the scalar mass however is shown to reappear in a new guise in five dimensional warped model when the two form antisymmetric tensor fields, a massless string mode, propagates in the bulk. Finally the issue of modulus stabilization is re-examined in presence of a bulk scalar by considering it's back-reaction on the background geometry. The role of higher derivative term of the bulk scalar is shown tomore » be crucial to achieve modulus stabilization.« less
  • The stability of the ground state and the possibility of the appearance of a phase transition in the supernormalizable nonlocal Yukawa-type field theory are investigated. A variational estimation of the upper bound for the effective potential is obtained. It is shown that there exists a finite critical value for the boson-fermion coupling constant. The initial vacuum becomes unstable when this coupling constant exceeds the critical value. As a result, the system under consideration goes into the phase with nonvanishing expectation value of the field.