Eur. Phys. J. C (2019) 79: 30
https://doi.org/10.1140/epjc/s10052-019-6550-9

Regular Article - Theoretical Physics

Scalar singlet dark matter in non-standard cosmologies

¹ Centro de Investigaciones, Universidad Antonio Nariño, Carrera 3 Este # 47A-15, Bogotá, Colombia
² Departamento de Física e Astronomia, Faculdade de Ciências da Universidade do Porto and Centro de Física do Porto, Rua do Campo Alegre 687, 4169-007, Porto, Portugal
³ Astronomy Unit, Queen Mary University of London, Mile End Road, London, E1 4NS, UK
⁴ NICPB, Rävala pst. 10, 10143, Tallinn, Estonia

^* e-mail: nicolas.bernal@uan.edu.co

Received: 9 July 2018
Accepted: 21 December 2018
Published online: 16 January 2019

Abstract

We study production of dark matter (DM) in models with a non-standard expansion history. We consider both freeze-out and freeze-in mechanisms for producing the observed DM abundance in a model where the DM consists of scalar singlet particles coupled to the Standard Model sector via the Higgs portal. We show that a non-standard expansion phase can lead to a significant change in the DM abundance and therefore to observational ramifications. For example, for DM freeze-in the required portal coupling can be much larger, whereas for DM freeze-out much smaller values become allowed. We evaluate the relevant constraints and discuss prospects for direct detection of such DM.