| Literature DB >> 26430384 |
Olivier Mattelaer1, Eleni Vryonidou2.
Abstract
We show how studies relevant for mono-X searches at the LHC in simplified models featuring a dark-matter candidate and an s-channel mediator can be performed within the MadGraph5_aMC@NLO framework. We focus on gluon-initiated loop-induced processes, mostly relevant to the case where the mediator couples preferentially to third generation quarks and in particular to the top quark. Our implementation allows us to study signatures at hadron colliders involving missing transverse energy plus jets or plus neutral bosons ([Formula: see text]), possibly including the effects of extra radiation by multi-parton merging and matching to the parton shower.Entities:
Year: 2015 PMID: 26430384 PMCID: PMC4581402 DOI: 10.1140/epjc/s10052-015-3665-5
Source DB: PubMed Journal: Eur Phys J C Part Fields ISSN: 1434-6044 Impact factor: 4.590
Mass benchmarks in GeV
| Benchmark | Resonant | Heavy mediator | Heavy DM |
|---|---|---|---|
| Mediator mass | 200 | 1000 | 400 |
| Dark-matter mass | 50 | 1 | 500 |
LO widths in GeV for the various mediators. The computation of the width has been performed with MadWidth [36]
| Benchmark | S | P | V | A |
|---|---|---|---|---|
| Resonant | 5.17 | 6.89 | 5.17 | 19.3 |
| Heavy mediator | 88.0 | 94.5 | 105.7 | 172 |
| Heavy DM | 3.10 | 11.89 | 22.2 | 36.0 |
Fig. 1Feynman diagrams contributing to jets plus missing transverse energy signal in the simplified model
Cross sections in pb for at 13 TeV for the scalar and pseudoscalar mediators for a cut of 50 and 200 GeV on the jet transverse momentum and the corresponding scale and PDF uncertainties for the LHC at 13 TeV
| Benchmark | Scalar | Pseudoscalar | ||
|---|---|---|---|---|
| Jet | 50 | 200 | 50 | 200 |
| Resonant | 4.11 | 0.244 | 10.1 | 0.584 |
| Heavy mediator | 3.22 | 4.92 | 4.23 | 6.47 |
| Heavy DM | 4.33 | 8.54 | 1.73 | 3.35 |
Cross section in pb for for the vector and axial-vector mediators for a cut of 50 and 200 GeV on the jet transverse momentum and the corresponding scale and PDF uncertainties for the LHC at 13 TeV
| Benchmark | Vector | Axial-vector | ||
|---|---|---|---|---|
| Jet | 50 | 200 | 50 | 200 |
| Resonant | 0.487 | 0.104 | 11.5 | 1.02 |
| Heavy mediator | 2.68 | 1.55 | 5.51 | 8.97 |
| Heavy DM | 1.48 | 1.09 | 1.28 | 2.50 |
Fig. 2Differential jet rate distributions for a scalar mediator in the resonant DM production scenario, for a merging scale of 60 GeV
Fig. 3Hardest and second hardest jet transverse momentum distribution for jets for a scalar mediator
Fig. 4Missing transverse momentum distribution for jets for a scalar mediator
Fig. 5Invariant mass distribution for the DM pair jets for a scalar mediator
Fig. 6Hardest and second hardest jet transverse momentum distribution for jets for a pseudoscalar mediator
Fig. 7Missing transverse momentum distribution for jets for a pseudoscalar mediator
Fig. 8Invariant mass distribution for the DM pair jets for a pseudoscalar mediator
Fig. 9Missing transverse momentum distribution for jets for a scalar mediator, using the exact loops (solid lines) and the top EFT (dashed lines) and the corresponding ratio
Fig. 10Hardest and second hardest jet transverse momentum distribution for jets for a vector mediator
Fig. 11Missing transverse momentum distribution for jets for a vector mediator
Fig. 12Invariant mass distribution for the DM pair jets for a vector mediator
Fig. 13Hardest and second hardest jet transverse momentum distribution for jets for an axial-vector mediator
Fig. 14Missing transverse momentum distribution for jets for an axial-vector mediator
Fig. 15Invariant mass distribution for the DM pair jets for an axial-vector mediator
Fig. 16Representative Feynman diagrams contributing to the mono-X processes in the simplified model
Cross sections (in pb) for gluon-induced mono-Z production at the LHC at TeV for three mass benchmarks. A technical cut of 2 GeV has been set on the transverse momentum of all final heavy states. No Z branching ratios are included
| Benchmark | Scalar | Pseudoscalar | Vector | Axial-vector |
|---|---|---|---|---|
| Resonant |
|
| 3.26 | 8.98 |
| Heavy mediator | 2.20 |
| 2.15 | 1.52 |
| Heavy DM |
|
| 1.05 | 1.10 |
Fig. 17Missing distribution for for the scalar (S) and pseudoscalar (P) mediators
Fig. 18Missing distribution for for the vector (V) and axial-vector (A) mediators
Fig. 19Missing distribution for for the scalar mediator of 200 GeV. The distributions are shown for two cuts on the transverse momentum of the jet
Cross sections (in pb) for gluon-induced mono-Higgs production at the LHC at TeV for the three mass benchmarks. A technical cut of 2 GeV has been set on the transverse momentum of all final heavy states, but no Higgs branching ratios are included
| Benchmark | Scalar | Pseudoscalar | Axial-vector |
|---|---|---|---|
| Resonant | 6.98 | 0.139 | 2.81 |
| Heavy mediator | 9.31 | 5.79 | 3.01 |
| Heavy DM | 1.28 | 2.44 | 2.07 |
Fig. 20Missing distribution for for the scalar (S) and pseudoscalar (P) mediators
Fig. 21Missing distribution for for the axial-vector mediator
Cross sections (in pb) for gluon-induced mono-photon production at the LHC at TeV for the three mass benchmarks. A 10 GeV cut is applied on the transverse momentum of the final state photon and
| Benchmark | Vector |
|---|---|
| Resonant | 3.18 |
| Heavy mediator | 1.98 |
| Heavy DM | 1.17 |
Fig. 22Missing transverse momentum distribution for for the three mass benchmarks. The only mediator giving non-zero results is the vector one