A Higgs factory is a particle accelerator designed to produce Higgs bosons at a very high rate, allowing precision studies of this particle.
A Higgs factory was identified as the highest future priority of particle physics in the 2020 European Strategy Report.
[1] This view was reaffirmed in 2022 by the International Committee on Future Accelerators.
However, unexplained phenomena such as dark matter lead physicists to think that the Standard Model is an incomplete theory and that new particles may exist.
Alternatively, the search can focus on careful measurements of properties of known particles, like the Higgs, that may be affected by interactions with the new particles that are not directly observed.