Chasing the Higgs shape at HL-LHC

The Higgs boson may well be a composite scalar with a finite extension in space. Owing to the momentum dependence of its couplings, the imprints of such a composite pseudo Goldstone Higgs may show up in the tails of various kinematic distributions at the LHC, distinguishing it from an elementary state. From the bottom up, we construct the momentum-dependent form factors to capture the interactions of the composite Higgs with the weak gauge bosons. We demonstrate their impact in the differential distributions of various kinematic parameters for the <math display="inline"><mi>p</mi><mi>p</mi><mo stretchy="false">→</mo><msup><mi>Z</mi><mo>*</mo></msup><mi>H</mi><mo stretchy="false">→</mo><msup><mi>l</mi><mo>+</mo></msup><msup><mi>l</mi><mo>-</mo></msup><mi>b</mi><mover accent="true"><mi>b</mi><mo stretchy="false">¯</mo></mover></math> channel. We show that this channel can provide an important handle to probe the Higgs’ substructure at the HL-LHC.