TY - JOUR
T1 - Self-consistent Dark Matter simplified models with an s-channel scalar mediator
AU - Bell, Nicole F.
AU - Busoni, Giorgio
AU - Sanderson, Isaac W.
N1 - Publisher Copyright:
© 2017 IOP Publishing Ltd and Sissa Medialab srl .
PY - 2017/3/8
Y1 - 2017/3/8
N2 - We examine Simplified Models in which fermionic DM interacts with Standard Model (SM) fermions via the exchange of an s-channel scalar mediator. The single-mediator version of this model is not gauge invariant, and instead we must consider models with two scalar mediators which mix and interfere. The minimal gauge invariant scenario involves the mixing of a new singlet scalar with the Standard Model Higgs boson, and is tightly constrained. We construct two Higgs doublet model (2HDM) extensions of this scenario, where the singlet mixes with the 2nd Higgs doublet. Compared with the one doublet model, this provides greater freedom for the masses and mixing angle of the scalar mediators, and their coupling to SM fermions. We outline constraints on these models, and discuss Yukawa structures that allow enhanced couplings, yet keep potentially dangerous flavour violating processes under control. We examine the direct detection phenomenology of these models, accounting for interference of the scalar mediators, and interference of different quarks in the nucleus. Regions of parameter space consistent with direct detection measurements are determined.
AB - We examine Simplified Models in which fermionic DM interacts with Standard Model (SM) fermions via the exchange of an s-channel scalar mediator. The single-mediator version of this model is not gauge invariant, and instead we must consider models with two scalar mediators which mix and interfere. The minimal gauge invariant scenario involves the mixing of a new singlet scalar with the Standard Model Higgs boson, and is tightly constrained. We construct two Higgs doublet model (2HDM) extensions of this scenario, where the singlet mixes with the 2nd Higgs doublet. Compared with the one doublet model, this provides greater freedom for the masses and mixing angle of the scalar mediators, and their coupling to SM fermions. We outline constraints on these models, and discuss Yukawa structures that allow enhanced couplings, yet keep potentially dangerous flavour violating processes under control. We examine the direct detection phenomenology of these models, accounting for interference of the scalar mediators, and interference of different quarks in the nucleus. Regions of parameter space consistent with direct detection measurements are determined.
KW - dark matter experiments
KW - dark matter theory
UR - http://www.scopus.com/inward/record.url?scp=85017035250&partnerID=8YFLogxK
U2 - 10.1088/1475-7516/2017/03/015
DO - 10.1088/1475-7516/2017/03/015
M3 - Article
SN - 1475-7516
VL - 2017
JO - Journal of Cosmology and Astroparticle Physics
JF - Journal of Cosmology and Astroparticle Physics
IS - 3
M1 - 015
ER -