Echoes of the Electroweak Phase Transition: Discovering a Second Higgs Doublet through A0 arrow right ZH0

• Published in: Physical review letters Vol. 113; no. 21
• Main Authors: Dorsch, G C, Huber, S J, Mimasu, K, No, J M
• Format: Journal Article
• Language: English
• Published: 21-11-2014
• Subjects: Asymmetry; Channels; Decomposition; Echoes; Phase transformations; Scalars; Signatures; Universe
• ISSN: 0031-9007; 1079-7114
• DOI: 10.1103/PhysRevLett.113.211802

The existence of a second Higgs doublet in nature could lead to a cosmological first-order electroweak phase transition and explain the origin of the matter-antimatter asymmetry in the Universe. We obtain the spectrum and properties of the new scalars H0, A0, and H+ or - that signal such a phase transition and show that the observation of the decay A0 arrow right ZH0 at LHC would be a "smoking gun" signature of these scenarios. We analyze the LHC search prospects for this decay in the [scriptl][scriptl]bb super(-) and [scriptl][scriptl]W+W- final states, arguing that current data may be sensitive to this signature in the former channel as well as there being great potential for a discovery in either channel at the very early stages of the 14 TeV run.