Les Houches

Chair: Andreas Goudelis

Members: Benjamin Fuks, Nishita Desai, Giacomo Polesello, Sanjoy Biswas, Suchita Kulkarni, Dipan Sengupta, Björn Herrmann, Daniel Schmeier, Daniele Barducci, Michele Frigerio, Aoife Bharucha, Genevieve Belanger

Main idea: Would an observed excess of j+MET events allow for a distinction of the underlying model? Can the monojet pT distribution differentiate among different SM-DM couplings? An enhancement of the signal for large pT occurs if the coupling is proportional to the exchanged momentum; this happens for a derivative coupling, typically encountered, e.g., in compositeness models.

Simplest example: The SM plus one singlet scalar DM, including a dim-6 operator coupling the Higgs doublet to the DM. A recent reference on this model: http://inspirehep.net/record/1341060?ln=en , see section 3.1.1, in particular eq.(3.3) for the Higgs-DM-DM coupling, if somebody is interested to generate the related pT distribution…

A preliminary study of the monojet signature in this model was performed in the master thesis by Sylvain Lacroix (2013, in French): see section 3.9 for the case without derivative coupling, and section 4.3 for the addition of the derivative operator.

Notes by M.Frigerio including motivations, the simplest model, and two non-minimal models are available here: monojetpt.pdf

Useful references

• Composite Dark Matter and LHC Interplay

http://arxiv.org/abs/1404.7419

• Dark Matter Constraints on Composite Higgs Models

http://arxiv.org/abs/1501.05957

• A rather inclusive summary on signatures of various EFT DM models

http://arxiv.org/abs/1506.03116

• The ATLAS/CMS Dark Matter forum summary

http://arxiv.org/abs/1507.00966

• A relevant MSc thesis from a student of Michele's (in French)

rapport.pdf

Tools

• UFO model file for some s-channel simplified models:

https://feynrules.irmp.ucl.ac.be/wiki/DMsimp

• FeynRules (with corresponding CalcHEP and UFO) model files for the singlet model, with an effective g-g-h vertex implemented for h production

compositedmleshouches.tar

Micromegas results scdm-micro.tar.gz