We study the prospect for discovering the $cg\to b{H}^{+}\to bA{W}^{+}$ process at the LHC. Induced by the top-flavor changing neutral Higgs coupling ${\rho }_{tc}$, the process may emerge if $m_{H^{+}}>m_A+m_{W^{+}}$, where $H^{+}$ and $A$ are charged and $CP$-odd Higgs bosons in the general two Higgs doublet model (g2HDM). We show that the $cg\to b{H}^{+}\to bA{W}^{+}$ process can be discovered at LHC run 3, while the full run 2 data at hand can constrain the parameter space significantly by searching for the same-sign dilepton final state. The process has unique implications on the hint of $gg\to A\to t\overline{t}$ excess at $m_A\approx 400\mathrm{GeV}$ reported by CMS. When combined with other existing constraints, the $cg\to b{H}^{+}\to bA{W}^{+}$ process can essentially rule out the g2HDM explanation of such an excess.

• Received 15 February 2021
• Accepted 29 March 2021

DOI:https://doi.org/10.1103/PhysRevD.103.075015

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP³.

Published by the American Physical Society