TY - JOUR

T1 - Large Higgs-electron Yukawa coupling in 2HDM

AU - Dery, Avital

AU - Frugiuele, Claudia

AU - Nir, Yosef

N1 - We thank Joao Silva and Ryosuke Sato for useful discussions. YN is the Amos de-Shalit chair of theoretical physics. YN is supported by grants from the Israel Science Foundation (grant number 394/16), the United States-Israel Binational Science Foundation (BSF), Jerusalem, Israel (grant number 2014230), the I-CORE program of the Planning and Budgeting Committee and the Israel Science Foundation (grant number 1937/12), and the Minerva Foundation. Article funded by SCOAP

PY - 2018/4/10

Y1 - 2018/4/10

N2 - The present upper bound on κ e, the ratio between the electron Yukawa coupling and its Standard Model value, is of O(600). We ask what would be the implications in case that κ e is close to this upper bound. The simplest extension that allows for such enhancement is that of two Higgs doublet models (2HDM) without natural flavor conservation. In this framework, we find the following consequences: (i) Under certain conditions, measuring κ e and κ V would be enough to predict values of Yukawa couplings for other fermions and for the H and A scalars. (ii) In the case that the scalar potential has a softly broken Z 2 symmetry, the second Higgs doublet must be light, but if there is hard breaking of the symmetry, the second Higgs doublet can be much heavier than the electroweak scale and still allow the electron Yukawa coupling to be very different from its SM value. (iii) CP must not be violated at a level higher than O(0.01 / κ e) in both the scalar potential and the Yukawa sector. (iv) LHC searches for e +e − resonances constrain this scenario in a significant way. Finally, we study the implications for models where one of the scalar doublets couples only to the first generation, or only to the third generation.

AB - The present upper bound on κ e, the ratio between the electron Yukawa coupling and its Standard Model value, is of O(600). We ask what would be the implications in case that κ e is close to this upper bound. The simplest extension that allows for such enhancement is that of two Higgs doublet models (2HDM) without natural flavor conservation. In this framework, we find the following consequences: (i) Under certain conditions, measuring κ e and κ V would be enough to predict values of Yukawa couplings for other fermions and for the H and A scalars. (ii) In the case that the scalar potential has a softly broken Z 2 symmetry, the second Higgs doublet must be light, but if there is hard breaking of the symmetry, the second Higgs doublet can be much heavier than the electroweak scale and still allow the electron Yukawa coupling to be very different from its SM value. (iii) CP must not be violated at a level higher than O(0.01 / κ e) in both the scalar potential and the Yukawa sector. (iv) LHC searches for e +e − resonances constrain this scenario in a significant way. Finally, we study the implications for models where one of the scalar doublets couples only to the first generation, or only to the third generation.

U2 - https://doi.org/10.1007/JHEP04(2018)044

DO - https://doi.org/10.1007/JHEP04(2018)044

M3 - مقالة

SN - 1029-8479

VL - 2018

JO - Journal of High Energy Physics

JF - Journal of High Energy Physics

IS - 4

M1 - 44

ER -