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arXiv · 1707.03000

Higgs data does not rule out a sequential fourth generation with an extended scalar sector

Dipankar Das·Anirban Kundu·Ipsita Saha
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Abstract

Contrary to the common perception, we show that the current Higgs data does not eliminate the possibility of a sequential fourth generation that get their masses through the same Higgs mechanism as the first three generations. The inability to fix the sign of the bottom-quark Yukawa coupling from the available data plays a crucial role in accommodating a chiral fourth generation which is consistent with the bounds on the Higgs signal strengths. We show that effects of such a fourth generation can remain completely hidden not only in the production of the Higgs boson through gluon fusion but also to its subsequent decay to $\gamma\gamma$ and $ Z\gamma$. This, however, is feasible only if the scalar sector of the Standard Model is extended. We also provide a practical example illustrating how our general prescription can be embedded in a realistic model.

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Dipankar Das, Anirban Kundu, Ipsita Saha. 2017-07-10. Higgs data does not rule out a sequential fourth generation with an extended scalar sector. https://doi.org/10.1103/physrevd.97.011701

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