# On Extra Top Yukawa Couplings of a Second Higgs Doublet

## Abstract

**:**

## 1. Introduction: Historical Development of Extra Top Yukawa Couplings

## 2. Two Sets of Dimension-4 Dynamical Operators

- CPV for EWBG calls for $\mathcal{O}\left(1\right)$ extra top Yukawa couplings, while first order phase transition calls for $\mathcal{O}\left(1\right)$ Higgs quartics. The latter, in turn, suggests sub-TeV exotic Higgs masses, as we shall see.
- For the electron EDM constraint, the diagonal extra electron Yukawa coupling ${\rho}_{ee}$ needs to correlate with extra top Yukawa coupling ${\rho}_{tt}$ that echoes the known Yukawa coupling pattern.

## 3. Driving EWBG and Facing eEDM: Extra tt, tc and ee Couplings

## 4. Crux of Production at Hadron Colliders: Extra tc Coupling

- 1.
- 2.
- $cg\to tH/tA\to tt\overline{t}$: Triple-Top [52];
- 3.

#### 4.1. Top-Associated Neutral Higgs Production

#### 4.2. Bottom-Associated Charged Higgs Production

#### 4.3. Enter the tu Coupling

## 5. Turning to Flavor: Ratio of B to Muon+Neutrino vs. Tau+Neutrino

## 6. Prospects and Conclusions

## Funding

## Acknowledgments

## Conflicts of Interest

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Hou, G.W.-S.
On Extra Top Yukawa Couplings of a Second Higgs Doublet. *Universe* **2022**, *8*, 475.
https://doi.org/10.3390/universe8090475

**AMA Style**

Hou GW-S.
On Extra Top Yukawa Couplings of a Second Higgs Doublet. *Universe*. 2022; 8(9):475.
https://doi.org/10.3390/universe8090475

**Chicago/Turabian Style**

Hou, George Wei-Shu.
2022. "On Extra Top Yukawa Couplings of a Second Higgs Doublet" *Universe* 8, no. 9: 475.
https://doi.org/10.3390/universe8090475