Dark Matter Gauge invariant simplified model with CP-even Spin-0 s-channel mediator

Authors

Giorgio Busoni (University of Melbourne) email: giorgio.busoni@…

Description of the model

This is a gauge-invariant simplified model for dark matter with a CP-even spin-0 mediator exchanged in the s-channel. Dark matter is taken to be a Dirac Fermion. For more details:

• ​1612.03475: Nicole F. Bell, Giorgio Busoni, Isaac W. Sanderson, "Self-consistent Dark Matter Simplified Models with an s-channel scalar mediator"

Model files

• S2HDM.fr: main model file for spin-0 mediators.
• ​Massless_4f.rst restriction file for 4F scheme.
• ​Massless_5f.rst: restriction file for 5F scheme.
• S2HDM.nb: this is an example Mathematica notebook that loads the model, checks consistency, calculates the Feynman rules and outputs the model in various formats.
• ​unitarity.m: additional mathematica file loaded by the mathematica notebook, that checks unitarity, perturbativity and stability of potential
• S2HDM_X.nlo files: NLOCT output, necessary to generate NLO UFO
• ​SM_CKM.fr: SM implementation with full CKM matrix, to output UFO with flavour-changing processes

Download

• Full package
• UFO Type I (5FS)
• UFO Type II (5FS)
• UFO Aligned (5FS)
• CALCHEP Aligned

Version updates

v1.0 release version
v0.7 prerelease version

Sample commands for MadGraph5_aMC@NLO

The UFO provided together with the feynrules model file was generated for four flavour scheme (4FS) calculations. To perform 5FS ones, you need to generate a new UFO by loading massless_5f restriction file instead of massless_4f.

Below we give the MadGraph syntax used to generate various mono-X signals

MONO-JET

generate p p > j ~xd ~xd~ [QCD]

Massive top and bottom quarks. 4FS calculation. This is LO as there are no tree level diagrams in this scheme.

MONO-H

generate p p > h ~xd ~xd~ [QCD]

Same notes as above.

MONO-Z

generate p p > z ~xd ~xd~ [QCD]

Same notes as above.

MONO-W

WARNING: needs 5FS UFO!

generate p p > w+ ~xd ~xd~ [QCD]

This has not been tested. This is LO as there are no tree level diagrams in this scheme.

TT+MET (tree level)

generate p p > t t~ ~xd ~xd~

Massive top and bottom quarks. 4FS calculation.

BB+MET (tree level)

generate p p > b b~ ~xd ~xd~

Massive top and bottom quarks. 4FS calculation.

TT+MET (NLO)

Not working yet. However you can generate

generate p p > t t~ S1 [QCD]

generate p p > t t~ S2 [QCD]

Massive top and bottom quarks. 4FS calculation. This is NLO accurate result including both top and bottom loops.

BB+MET (NLO)

same as above.

DI-JET+MET

WARNING: to make 5FS you need to output a new UFO with the right restrictions

generate p p > j j ~xd ~xd~ [QCD]

Massive top and bottom quarks. 4FS calculation. This is LO as there are no tree level diagrams in this scheme.

To use 5FS, you need to generate a new UFO output by loading massless_5f restriction file instead of massless_4f.