APEC Seminar (Astronomy - Particle Physics - Experimental Physics - Cosmology)

Speaker: Gautam Bhattacharyya (Saha Institute of Nuclear Physics, Kolkata)
Title: 2HDM scalar potential and the role of symmetries
Date (JST): Wed, May 13, 2015, 13:30 - 14:30
Place: Seminar Room A
Related File: 1458.pdf
Abstract: Theory and phenomenology of Two-Higgs-Doublet models (2HDM) has a vast literature. It is not my intention to discuss these models in entirety. However, the present situation demands a revisit of certain 2HDM properties. Now that a 125 GeV scalar resonance has been discovered at the LHC, with its couplings to other particles showing increasing similarity with those of the Standard Model Higgs boson, the nonstandard parameter space is now more squeezed than ever. I briefly review the different parametrizations of the 2HDM potential and discuss the constraints on the parameter space arising from the unitarity and stability of the potential together with constraints from the oblique electroweak $T$-parameter. I also differentiate the consequences of imposing a global continuous (1) symmetry on the potential from a discrete $Z_2$ symmetry.