A search for a Higgs boson with suppressed couplings to fermions, $h_f$, assumed to be the neutral, lower-mass partner of the Higgs boson discovered at the Large Hadron Collider, is reported. Such a Higgs boson could exist in extensions of the standard model with two Higgs doublets, and could be produced via $p\overline{p}\to H^{\pm }{h}_f\to W^{*}{h}_f{h}_f\to 4\gamma +X$, where $H^{\pm }$ is a charged Higgs boson. This analysis uses all events with at least three photons in the final state from proton-antiproton collisions at a center-of-mass energy of 1.96 TeV collected by the Collider Detector at Fermilab, corresponding to an integrated luminosity of $9.2{\mathrm{fb}}^{-1}$. No evidence of a signal is observed in the data. Values of Higgs-boson masses between 10 and $100\mathrm{GeV}/c^2$ are excluded at 95% Bayesian credibility.

• Received 4 January 2016

DOI:https://doi.org/10.1103/PhysRevD.93.112010