Abstract:
Heavy Higgs resonance shapes in golden channels are significantly affected from the interference with continuum backgrounds. Remarkably, the imaginary-part interference (with a relative phase) that has been mostly overlooked can produce strikingly new resonance shapes that the real-part interference alone cannot produce: pure dips, nothingness and rescaled pure peaks. Narrow-width approximation also has to be modified. We derive general conditions for each shape and demonstrate that MSSM or 2HDM generally produces such new shapes. We then identify inevitable challenges in LHC heavy Higgs searches and discuss possible resolutions.

Ref: 1505.00291, 1510.03450