Strong dynamics in a classically scale invariant extension of the standard model with a flat potential
Strong dynamics in a classically scale invariant extension of the standard model with a flat potential
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具有平坦势的标准模型的经典尺度不变扩展中的强动态
DOI：
10.1103/physrevd.95.115016
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发表时间：
2017
影响因子：
5
通讯作者：
Yamada Toshifumi
中科院分区：
文献类型：
--
作者：
Haba Naoyuki;Yamada Toshifumi
我们研究了标准模型通过经典尺度不变性进行扩展的场景，这种不变性被手性对称破缺和类似于 QCD 的新强耦合规范理论中的限制所打破。标准模型希格斯场是新强动力学中的标量介子与无质量基本标量场混合的结果。在新规范理论中动态生成的标量介子的质量和标量衰变常数产生了希格斯场质量项，并通过玻色子跷跷板机制自动拥有正确的负号。类比QCD，我们评估了新规范理论的动力学尺度，并进一步对新规范理论中与轴对称沿手性对称破缺相关的轻赝南部-戈德斯通玻色子进行了定量预测。这种情况的一个突出结果是，应该存在一个质量低于 220 GeV 的标准模型规范单线态准南部-戈德斯通玻色子，它通过韦斯-祖米诺-维滕项与两个电弱规范玻色子耦合，其强度因此由新规范理论的动力学尺度决定。其他在电弱规范组下带电的伪南部-戈德斯通玻色子也出现了。在理论方面，结果表明，标量四次耦合可以在普朗克尺度上消失，顶夸克极质量高达 172.5 GeV，实现平地场景，而不会与当前的实验数据产生紧张。
We investigate the scenario where the standard model is extended with classical scale invariance, which is broken by chiral symmetry breaking and confinement in a new strongly coupled gauge theory that resembles QCD. The standard model Higgs field emerges as a result of the mixing of a scalar meson in the new strong dynamics and a massless elementary scalar field. The mass and scalar decay constant of that scalar meson, which are generated dynamically in the new gauge theory, give rise to the Higgs field mass term, automatically possessing the correct negative sign by the bosonic seesaw mechanism. Using analogy with QCD, we evaluate the dynamical scale of the new gauge theory and further make quantitative predictions for light pseudo-Nambu-Goldstone bosons associated with the spontaneous breaking of axial symmetry along chiral symmetry breaking in the new gauge theory. A prominent consequence of the scenario is that there should be a standard model gauge singlet pseudo-Nambu-Goldstone boson with mass below 220 GeV, which couples to two electroweak gauge bosons through the Wess-Zumino-Witten term, whose strength is thus determined by the dynamical scale of the new gauge theory. Other pseudo-Nambu-Goldstone bosons, charged under the electroweak gauge groups, also appear. Concerning the theoretical aspects, it is shown that the scalar quartic coupling can vanish at the Planck scale with the top quark pole mass as large as 172.5 GeV, realizing the flatland scenario without being in tension with the current experimental data.