Neutrino Mass and Singlet in BSM
- PDF / 595,879 Bytes
- 6 Pages / 612 x 792 pts (letter) Page_size
- 39 Downloads / 219 Views
eutrino Mass and Singlet in BSM C. R. Dasa, *, Timo J. Kärkkäinenb, **, and Katri Huituc, *** a Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, International Intergovernmental Organization, Dubna, Moscow oblast, 141980 Russia b Institute for Theoretical Physics, ELTE Eotvos Lorand University, Budapest, 1117 Hungary c Department of Physics and Helsinki Institute of Physics, P. O. Box 64, University of Helsinki, Helsinki, FI-00014 Finland *e-mail: [email protected] **e-mail: [email protected] ***e-mail: [email protected]
Received December 20, 2019; revised January 16, 2020; accepted January 29, 2020
Abstract—We perform a phenomenological analysis of the observable consequences on the extended scalar sector of the SMASH (Standard Model–Axion–Seesaw–Higgs portal inflation) framework. We solve the vacuum metastability problem in a suitable region of SMASH scalar parameter spaces and discuss the oneloop correction to triple Higgs coupling λ HHH . We also find that the correct neutrino masses and mass squared differences and baryonic asymmetry of the universe can arise from this model and consider running of the Yukawa couplings of the model. In fact, we perform a full two-loop renormalization group analysis of the SMASH model. DOI: 10.1134/S106377962004022X
THE TRI-LINEAR HIGGS COUPLING IN SMASH FRAMEWORK SMASH (Standard Model–Axion–Seesaw–Higgs portal inflation) framework [1–3] expands the scalar sector of the SM by introducing a complex singlet field iA v (1) σ = 1 ( v σ + ρ) e σ , 2 where ρ and A (the axion) are real scalar fields, and vσ @ v is the VEV of the complex singlet. The scalar potential of SMASH is then 2
2
2 ⎛ 2 v2 ⎞ ⎛ † ⎞ V (H , σ) = λ H ⎜ H H − v ⎟ + λ σ ⎜ σ − σ ⎟ 2⎠ 2⎠ ⎝ ⎝ (2) 2 2 ⎛ † ⎞ ⎛ 2 vσ ⎞ v + 2λ H σ ⎜ H H − ⎟ ⎜ σ − ⎟ . 2 ⎠⎝ 2⎠ ⎝ Defining ϕ1 = H and ϕ2 = σ, the scalar mass matrix of this potential is
(M ij ) = 1 ∂ V 2 ∂ϕi ∂ϕ j H =v 2
σ= vσ
2, 2
=
2 ⎛ ⎜ 2λ H v ⎜ ⎜ 2λ H σv σ ⎝
2λH σvvσ ⎞⎟ ⎟, 2λσvσ2 ⎟⎠
(3)
mechanism, through complex singlet σ. It arises from Yukawa term:
Y4 vσ (4) . 2 We will show later that Y4 = 2(1) is forbidden by vacuum stability requirement. The hypercharge of 4 is chosen to be q = − 1 3, even though also q = 2 3 is possible. Our analysis is almost independent of the hypercharge assignment. Consider an energy scale below mσ < ΛIS, where the heavy scalar σ is integrated out. The low-energy Higgs potential should match the SM Higgs potential:
+Y4 = Y44σ4 ⇒ m4 ≈
2 2
⎛ † v ⎞. (5) V (H ) = λSM H ⎜H H − 2 ⎟⎠ ⎝ It turns out that the quartic coupling we measure has an additional term: λ2H σ (6) . λσ Since the SM Higgs quartic coupling will be approximately λ H (M Pl ) ≈ −0.02, the threshold correction λH = λH − SM
which has eigenvalues mH2 ≈ 2 ⎛⎜⎝ λ H v 2 + λ H σvσ2 ⎞⎟⎠ and
mσ2 ≈ 2 ⎛⎜⎝ λσvσ2 + λ H σv 2 ⎞⎟⎠ . The SMASH framework also includes a new quark-like field 4, which has colour but is an electroweak singlet. It gains its mass via Higgs
δ≡
λ 2H σ λσ
(7)
should have a minimum value close to λ H (M Pl ) or slightl
Data Loading...
