分类： 天文学 >> 天文学 提交时间： 2023-02-19
摘要： One of the simplest ways to account for the observed W-boson mass shift is to introduce the $SU(2)_L$ triplet Higgs boson with zero hypercharge, whose vacuum expectation value is about 3 GeV. If the triplet is heavy enough at $\mathcal{O}(1)$ TeV, it essentially contributes only to $T$ parameter without any conflict to the observation. The presence of a complex triplet Higgs boson raises the $SU(2)_L$ gauge coupling constant to $\alpha_2(M_{\rm PL} )\simeq 1/44$ at the Planck scale. Thanks to this larger gauge coupling constant, we show that the electroweak axion vacuum energy explains the observed cosmological constant provided that the axion field is located near the hill top of the potential at present.
分类： 天文学 >> 天文学 提交时间： 2023-02-19
摘要： The electroweak axion is identified with the fuzzy dark matter of a mass $m\simeq 10^{-20}$--$10^{-19}\,{\rm eV}$. The model predicts two components of dark matter, one is ultralight and the other is WIMP-like. The Chern-Simons-type interaction between the fuzzy dark matter and photon and the $B+L$ breaking proton decays are predicted.
分类： 天文学 >> 天文学 提交时间： 2023-02-19
摘要： We revisit the constraint from the recently reported cosmic birefringence on axion-like particles with a general decay constant. A particular attention is paid to the naturalness of the model parameter space, which has been overlooked in the literature. We show that the observed cosmic birefringence is naturally explained by the electroweak axion with a string-theory inspired decay constant $F_A\simeq 10^{16}$ GeV.
分类： 天文学 >> 天文学 提交时间： 2023-02-19
摘要： The $U(1)_{B\textrm{--}L}$ symmetry, the essential component in the seesaw mechanism and leptogenesis, is naturally equipped with a massive gauge boson. If this gauge boson is the dark matter, the scenario consistent with the seesaw mechanism predicts the gauge coupling to be of the order of $\mathcal{O}(10^{-19})$ for masses $\lesssim1$ MeV, dominantly decaying into active neutrinos. We stress and explore the important role of astrophysical neutrinos of energies from $\mathcal{O}(1)$ keV to $\sim1$ MeV in testing the well-motivated $B$-$L$ symmetry extension to the Standard Model, which has been missed in the literature to date. Compared to other dark matter models, the neutrino flux in the sub-MeV energy range is a unique prediction in our setup and, once detected, would serve as a smoking gun for the existence of this $B$-$L$ gauge boson and its role as the dark matter particle, opening new windows to tackle cosmological and astrophysical conundra.
分类： 天文学 >> 天文学 提交时间： 2023-02-19
摘要： One of the simplest ways to account for the observed W-boson mass shift is to introduce the $SU(2)_L$ triplet Higgs boson with zero hypercharge, whose vacuum expectation value is about 3 GeV. If the triplet is heavy enough at $\mathcal{O}(1)$ TeV, it essentially contributes only to $T$ parameter without any conflict to the observation. The presence of a complex triplet Higgs boson raises the $SU(2)_L$ gauge coupling constant to $\alpha_2(M_{\rm PL} )\simeq 1/44$ at the Planck scale. Thanks to this larger gauge coupling constant, we show that the electroweak axion vacuum energy explains the observed cosmological constant provided that the axion field is located near the hill top of the potential at present.
分类： 天文学 >> 天文学 提交时间： 2023-02-19
摘要： We revisit the constraint from the recently reported cosmic birefringence on axion-like particles with a general decay constant. A particular attention is paid to the naturalness of the model parameter space, which has been overlooked in the literature. We show that the observed cosmic birefringence is naturally explained by the electroweak axion with a string-theory inspired decay constant $F_A\simeq 10^{16}$ GeV.
分类： 天文学 >> 天文学 提交时间： 2023-02-19
摘要： The $U(1)_{B\textrm{--}L}$ symmetry, the essential component in the seesaw mechanism and leptogenesis, is naturally equipped with a massive gauge boson. If this gauge boson is the dark matter, the scenario consistent with the seesaw mechanism predicts the gauge coupling to be of the order of $\mathcal{O}(10^{-19})$ for masses $\lesssim1$ MeV, dominantly decaying into active neutrinos. We stress and explore the important role of astrophysical neutrinos of energies from $\mathcal{O}(1)$ keV to $\sim1$ MeV in testing the well-motivated $B$-$L$ symmetry extension to the Standard Model, which has been missed in the literature to date. Compared to other dark matter models, the neutrino flux in the sub-MeV energy range is a unique prediction in our setup and, once detected, would serve as a smoking gun for the existence of this $B$-$L$ gauge boson and its role as the dark matter particle, opening new windows to tackle cosmological and astrophysical conundra.
分类： 天文学 >> 天文学 提交时间： 2023-02-19
摘要： Recently, arXiv:2210.05659 shows that a photon-axion like particle (ALP) oscillation can boost the survival rate of the high energy photons associated with the observed GRB221009A event. Here, we show that the proposed ALP is consistent with the electroweak axion with an anomaly free $Z_{10}$ Froggatt-Nielsen symmetry.
分类： 天文学 >> 天文学 提交时间： 2023-02-19
摘要： The electroweak axion is identified with the fuzzy dark matter of a mass $m\simeq 10^{-20}$--$10^{-19}\,{\rm eV}$. The model predicts two components of dark matter, one is ultralight and the other is WIMP-like. The Chern-Simons-type interaction between the fuzzy dark matter and photon and the $B+L$ breaking proton decays are predicted.
分类： 天文学 >> 天文学 提交时间： 2023-02-19
摘要： Recently, arXiv:2210.05659 shows that a photon-axion like particle (ALP) oscillation can boost the survival rate of the high energy photons associated with the observed GRB221009A event. Here, we show that the proposed ALP is consistent with the electroweak axion with an anomaly free $Z_{10}$ Froggatt-Nielsen symmetry.
分类： 物理学 >> 基本粒子与场物理学 提交时间： 2017-08-03
摘要： We propose a gauged U(1)H horizontal symmetry around TeV scale that is a subgroup of a SU(3)H horizontal gauge symmetry broken at O(1014) GeV. The breaking generates right-handed Majorana neutrino masses through a SU(3)H sextet scalar. A particular Majorana right-handed neutrino mass matrix explicitly determines the remnant U(1)H at low energy which only couples to b−s and µ−τ in the gauge eigenstate. The dangerous K − K¯ , D − D¯ mixing and Bs → µ +µ − are kept to be safe because the relevant couplings are suppressed through high powers of small mixing angles in the fermion rotation matrix. Our analysis which applies to the general case shows that the Tevatron di-muon anomaly can be explained through the Bs and Bd mixing while keeping all the other experimental constraints within 90 % C. L. For the B meson decay, the Bs → µ ±τ ∓ is the leading leptonic decay channel which is several orders of magnitude below current experimental bound
点击量
待评议
点击量
下载量
评论
