Classically conformal U(1)′ extended standard model and Higgs vacuum stability

被引:78
作者
Oda, Satsuki [1 ,2 ]
Okada, Nobuchika [3 ]
Takahashi, Dai-suke [1 ,2 ]
机构
[1] Okinawa Inst Sci & Technol, Grad Sch OIST, Onna, Okinawa 9040495, Japan
[2] Meio Univ, Res Inst, Nago City, Okinawa 9058585, Japan
[3] Univ Alabama, Dept Phys & Astron, Tuscaloosa, AL 35487 USA
关键词
GAUGE BOSONS; SYMMETRY; MASS;
D O I
10.1103/PhysRevD.92.015026
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We consider the minimal U(1)' extension of the standard model (SM) with conformal invariance at the classical level, where in addition to the SM particle contents, three generations of right-handed neutrinos and a U(1)' Higgs field are introduced. In the presence of the three right-handed neutrinos, which are responsible for the seesaw mechanism, this model is free from all the gauge and gravitational anomalies. The U(1)' gauge symmetry is radiatively broken via the Coleman-Weinberg mechanism, by which the U(1)' gauge boson (Z' boson) mass as well as the Majorana mass for the right-handed neutrinos are generated. The radiative U(1)' symmetry breaking also induces a negative mass squared for the SM Higgs doublet to trigger the electroweak symmetry breaking. In this context, we investigate a possibility to solve the SM Higgs vacuum instability problem. The model includes only three free parameters (U(1)' charge of the SM Higgs doublet, U(1)' gauge coupling and Z' boson mass), for which we perform parameter scan, and identify a parameter region resolving the SM Higgs vacuum instability. We also examine naturalness of the model. The heavy states associated with the U(1)' symmetry breaking contribute to the SM Higgs self-energy. We find an upper bound on Z' boson mass, m(Z') less than or similar to 0.6 TeV, in order to avoid a fine-tuning severer than 10% level. The Z' boson in this mass range can be discovered at the LHC Run-2 in the near future.
引用
收藏
页数:11
相关论文
共 45 条
[41]   Neutrinos, axions and conformal symmetry [J].
Meissner, Krzysztof A. ;
Nicolai, Hermann .
EUROPEAN PHYSICAL JOURNAL C, 2008, 57 (03) :493-498
[42]   MU-]EGAMMA AT A RATE OF ONE OUT OF 109 MUON DECAYS [J].
MINKOWSKI, P .
PHYSICS LETTERS B, 1977, 67 (04) :421-428
[43]   NEUTRINO MASS AND SPONTANEOUS PARITY NON-CONSERVATION [J].
MOHAPATRA, RN ;
SENJANOVIC, G .
PHYSICAL REVIEW LETTERS, 1980, 44 (14) :912-915
[44]  
OKADA N, IN PRESS
[45]  
Yanagida T., 1979, Conf. Proc, P95