Free Meson Seminars

On the Validity of the Effective Potential and the Precision of Higgs Self Couplings

by Dr. Bithika Jain (Korea Institute for Advanced Study, Seoul)

Thursday, November 23, 2017 from to (Asia/Kolkata)
at AG69
The global picture of the Higgs potential in the bottom-up approach is still unknown. A large deviation as big as O(1) fluctuations of the Higgs self couplings is still a viable option for the New Physics. An interesting New Physics scenario that can be linked to a large Higgs self coupling is the baryogenesis based on the strong first order phase transition. We revisit the strong first order phase transition in two classes of Beyond the Standard Models, namely the Higgs portal with the singlet scalar under the Standard Model gauge group with the Z2 symmetry and the effective field theory approach with higher-dimensional operators. We investigate a few important issues in the validity of the effective potential, caused by the breakdown of the high-temperature approximation, and in the criteria for the strong first order phase transition. We illustrate that these issues can lead to O(1) uncertainties in the precision of the Higgs self couplings, which are relevant when discussing sensitivity limits of different future colliders. We show that the correlation between the Higgs trilinear coupling and the quartic coupling will be useful for differentiating various underlying New Physics scenarios and discuss its prospect for the future colliders.