Determine the impact of momentum-dependent Higgs-sector operators on portal discrimination

Determine whether momentum-dependent observables, such as the invariant-mass distribution of di-Higgs production, can discriminate among the marginal scalar Higgs portal, the dimension-five fermionic Higgs portal, and the dimension-six vector Higgs portal when additional Higgs-sector Wilson coefficients are generated by the ultraviolet completion.

Background

The analysis assumes that the additional Wilson coefficients generated in the effective Higgs sector vanish at a reference scale, so that the calculated Higgs-coupling modifications arise from the portal interactions alone. Relaxing this assumption introduces independent contributions that cannot be constrained using only the two coupling modifications studied in the paper.

The paper identifies momentum-dependent observables, particularly the di-Higgs invariant-mass distribution, as the measurements needed to distinguish these additional effects and thereby retain sensitivity to the underlying portal. A dedicated analysis of this possibility is not performed.

References

Relaxing this assumption introduces further free, non-zero Wilson coefficients that the two coupling modifications considered here cannot constrain. Discriminating the portals would then require observables sensitive to the momentum dependence that distinguishes the corresponding operators, such as the $m_{hh}$ distribution in di-Higgs production, which we leave to future work.

— A phenomenological profile of Higgs portals at future colliders  (2609.19258 - Detering et al., 16 Sep 2026) in Appendix, Section ‘Renormalisation and radiative corrections’