Lowest limits on the doubly charged Higgs boson masses in the minimal left-right symmetric model

Abstract

The doubly charged Higgs bosons ${H}_{1,2}^{\ifmmode\pm\else\textpm\fi{}\ifmmode\pm\else\textpm\fi{}}$ would undoubtedly be clear messengers of the new physics. We discuss their mass spectrum and show how experimental data and relations between scalar masses put limits on it. In particular, both the masses of the particles ${H}_{1}^{0}$, ${A}_{1}^{0}$ that play a crucial role in flavor changing neutral current effects and the masses of the additional gauge bosons ${W}_{2}$, ${Z}_{2}$ are notably important. For instance, if ${M}_{{H}_{1}^{0},{A}_{1}^{0}}\ensuremath{\simeq}15\text{ }\text{ }\mathrm{TeV}$ and ${M}_{{W}_{2}}\ensuremath{\simeq}3.76\text{ }\text{ }\mathrm{TeV}$, then the lowest mass of ${H}_{1}^{\ifmmode\pm\else\textpm\fi{}\ifmmode\pm\else\textpm\fi{}}$ is 465 GeV. In contrast, because of the freedom in the parameter space of the full scalar potential, there is no lowest limit on the mass of ${H}_{2}^{\ifmmode\pm\else\textpm\fi{}\ifmmode\pm\else\textpm\fi{}}$. It is shown to which signals at hadron colliders such relatively light doubly charged scalars might correspond. LHC working at $\sqrt{s}=14\text{ }\text{ }\mathrm{TeV}$ will enter into the region where the existence of such particles with minimal masses can be thoroughly explored for a much wider parameter space of the minimal and manifest version of the left-right symmetric model (MLRSM). Taking into account our considerations and present ATLAS and CMS exclusion limits on ${M}_{{H}^{\ifmmode\pm\else\textpm\fi{}\ifmmode\pm\else\textpm\fi{}}}$, there exist already first partial bounds on some of the MLRSM scalar potential parameters.