Deconstructing resonant Higgs boson pair production at the LHC: Effects of colored and neutral scalars in the NMSSM test case

We study resonant production of pairs of Standard Model (SM-)like Higgs bosons, in the presence of new neutral Higgs states together with new colored scalars (stops or sbottoms) in loops within the Next-to-Minimal Supersymmetric Standard Model. This is used as a test case to prove that the Large Hadron Collider has sensitivity to a variety of effects stemming from interferences between resonant (heavy) Higgs diagrams and/or among these and nonresonant topologies involving loops of both tops and stops. These effects can alter significantly the naive description of individual <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mrow><a:mi>s</a:mi></a:mrow></a:math>-channel Breit-Wigner resonances, leading to distortions of the latter, which, on the one hand, may mask their presence but, on the other hand, could enable one to extract features of the underlying new physics scenario. This last aspect is made possible through a decomposition of the <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"><c:mi>g</c:mi><c:mi>g</c:mi><c:mo stretchy="false">→</c:mo><c:mi>h</c:mi><c:mi>h</c:mi></c:math> signal process into all its amplitude components, each of which has a well-defined coupling structure. Ultimately, such effects can be traced back to the relevant Feynman diagrams and can enable a detailed interpretation of this process. To illustrate this, we introduce various benchmark points that exhibit potentially observable features during the current and/or upcoming runs of the LHC in one or more of the three customary di-Higgs decay channels: <f:math xmlns:f="http://www.w3.org/1998/Math/MathML" display="inline"><f:mi>b</f:mi><f:mover accent="true"><f:mi>b</f:mi><f:mo stretchy="false">¯</f:mo></f:mover><f:mi>b</f:mi><f:mover accent="true"><f:mi>b</f:mi><f:mo stretchy="false">¯</f:mo></f:mover></f:math>, <l:math xmlns:l="http://www.w3.org/1998/Math/MathML" display="inline"><l:mi>b</l:mi><l:mover accent="true"><l:mi>b</l:mi><l:mo stretchy="false">¯</l:mo></l:mover><l:msup><l:mi>τ</l:mi><l:mo>+</l:mo></l:msup><l:msup><l:mi>τ</l:mi><l:mo>−</l:mo></l:msup></l:math>, and <p:math xmlns:p="http://www.w3.org/1998/Math/MathML" display="inline"><p:mi>b</p:mi><p:mover accent="true"><p:mi>b</p:mi><p:mo stretchy="false">¯</p:mo></p:mover><p:mi>γ</p:mi><p:mi>γ</p:mi></p:math>.