Jayita Lahiri

Eur. Phys. J. C (2026) 86: 384 https://doi.org/10.1140/epjc/s10052-026-15415-7 Regular Article - Theoretical Physics Search for dark matter in 2HDMS at LHC and future lepton colliders 1,2, 3, 4a, 3,5, 3 and 3 1 Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, 73019, Norman, OK, USA 2 The Institute of Mathematical Sciences, 4th Cross St, CIT Campus, Tharamani, 600113, Chennai, Tamil Nadu, India 3 II.

A dark matter (DM) having feeble interaction with the visible sector can thermalize via substantial interaction with a weakly interacting massive particle (WIMP). Such DM candidates can be categorized as pseudofeebly interacting massive particles (pFIMPs). pFIMPs have both direct and indirect search prospects via a WIMP loop. This work focuses on such possibilities.

Abstract We study the coscattering mechanism in a simple Higgs portal which add two real singlet scalars to the Standard Model. In this scenario, the lighter scalar is stabilized by a single $\mathcal{Z}_2$ symmetry and acts as the dark matter relic, whose freeze-out is driven by conversion processes. The heavier scalar becomes an unstable state which participate actively in the coscattering.