https://doi.org/10.1140/epjc/s10052-018-6149-6
Regular Article - Theoretical Physics
Monojet signatures from heavy colored particles: future collider sensitivities and theoretical uncertainties
1
Theory Center, IPNS, KEK, Tsukuba, Ibaraki, 305-0801, Japan
2
SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA
3
The Graduate University of Advanced Studies (Sokendai), Tsukuba, Ibaraki, 305-0801, Japan
4
Kavli IPMU (WPI), University of Tokyo, Kashiwa, Chiba, 277-8583, Japan
5
Department of Physics, Institute for Particle Physics Phenomenology (IPPP), Durham University, Durham, DH1 3LE, UK
* e-mail: sunghak.lim@kek.jp
Received:
5
June
2018
Accepted:
10
August
2018
Published online:
25
August
2018
In models with colored particle 
that can decay into a dark matter candidate X, the relevant collider process 
jets gives rise to events with significant transverse momentum imbalance. When the masses of and X are very close, the relevant signature becomes monojet-like, and Large Hadron Collider (LHC) search limits become much less constraining. In this paper, we study the current and anticipated experimental sensitivity to such particles at the High-Luminosity LHC at 
TeV with 
ab
of data and the proposed High-Energy LHC at 
TeV with 
ab of data. We estimate the reach for various Lorentz and QCD color representations of . Identifying the nature of is very important to understanding the physics behind the monojet signature. Therefore, we also study the dependence of the observables built from the 
process on itself. Using the state-of-the-art Monte Carlo suites MadGraph5_aMC@NLO+Pythia8 and Sherpa, we find that when these observables are calculated at NLO in QCD with parton shower matching and multijet merging, the residual theoretical uncertainties are comparable to differences observed when varying the quantum numbers of itself. We find, however, that the precision achievable with NNLO calculations, where available, can resolve this dilemma.
© The Author(s), 2018
