Precision Electroweak Constraints on Neutrinophilic Scalars
Abstract
Strong self-interaction among the active neutrinos mediated by a neutrinophilic scalar is a well-motivated target of particle physics and cosmological probes. In this article, we present precision electroweak constraints on models for neutrino self-interaction. We first work in the simplified model where the finite radiative corrections are obtained with the guidance of gauge invariance. These corrections are logarithmically enhanced for small mediator masses. We point out the importance of neutrino charged-current coupling correction and its impact on the Δr parameter and Fermi constant measurements. This effect was overlooked previously and allows us to derive the leading constraint on the neutrinophilic couplings for mediator mass above a few hundred MeV. We investigate the robustness of the result in a concrete UV completion which further includes a TeV-scale SU(2)L triplet scalar and find the simplified model constraints continue to hold for a wide range of parameter space. We pin down moving parts in the UV complete model and conditions when the contributions from heavy particle loops are no longer negligible. Our results serve as a useful road map for future explorations of the self-interacting neutrino paradigm.
Versions
Related
- Probing Neutrinophilic Scalars in Muon Decays
- Precision Electroweak Physics of Neutral Currents Below the Z-pole
- Electroweak Constraints on Nuclear Neutron Distributions and the Low-Energy Weak Mixing Angle
- Constraints on Complex Electroweak WIMPs from Solar Capture
- SMEFT Constraints on Top Electroweak Couplings and a Composite Higgs Interpretation
BibTeX
@misc{foroughiabari2026precision,
title = {{Precision Electroweak Constraints on Neutrinophilic Scalars}},
author = {Saeid Foroughi-Abari and Camilla Mupo and Drona Vatsyayan and Yue Zhang},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2606.02704},
eprint = {2606.02704},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2606.02704},
}
RIS
TY - UNPB
TI - Precision Electroweak Constraints on Neutrinophilic Scalars
AU - Saeid Foroughi-Abari
AU - Camilla Mupo
AU - Drona Vatsyayan
AU - Yue Zhang
PY - 2026
DA - 2026/09/14
PB - arXiv
DO - 10.48550/arxiv.2606.02704
UR - https://arxiv.org/abs/2606.02704
AB - Strong self-interaction among the active neutrinos mediated by a neutrinophilic scalar is a well-motivated target of particle physics and cosmological probes. In this article, we present precision electroweak constraints on models for neutrino self-interaction. We first work in the simplified model where the finite radiative corrections are obtained with the guidance of gauge invariance. These corrections are logarithmically enhanced for small mediator masses. We point out the importance of neutrino charged-current coupling correction and its impact on the Δr parameter and Fermi constant measurements. This effect was overlooked previously and allows us to derive the leading constraint on the neutrinophilic couplings for mediator mass above a few hundred MeV. We investigate the robustness of the result in a concrete UV completion which further includes a TeV-scale SU(2)_L triplet scalar and find the simplified model constraints continue to hold for a wide range of parameter space. We pin down moving parts in the UV complete model and conditions when the contributions from heavy particle loops are no longer negligible. Our results serve as a useful road map for future explorations of the self-interacting neutrino paradigm.
ER -