A bstract The identity of Dark Matter (DM) is one of the most active topics in particle physics today. Supersymmetry (SUSY) is an extension of the standard model (SM) that could describe the particle nature of DM in the form of the lightest neutralino in R-parity conserving models. We focus on SUSY models that solve the hierarchy problem with small fine tuning, and where the lightest SUSY particles $$ \left({\tilde{\upchi}}_1^0,{\tilde{\upchi}}_1^{\pm },{\tilde{\upchi}}_2^0\right) $$ χ ˜ 1 0 χ ˜ 1 ± χ ˜ 2 0 are a triplet of higgsino-like states, such that the mass difference $$ \Delta m\left({\tilde{\upchi}}_2^0,{\tilde{\upchi}}_1^0\right) $$ Δ m χ ˜ 2 0 χ ˜ 1 0 is 0.5–50 GeV. We perform a feasibility study to assess the long-term discovery potential for these compressed SUSY models with higgsino-like states, using vector boson fusion (VBF) processes in the context of proton-proton collisions at $$ \sqrt{s} $$ s = 13 TeV, at the CERN Large Hadron Collider. Assuming an integrated luminosity of 3000 fb − 1 , we find that stringent VBF requirements, combined with large missing momentum and one or two low- p T leptons, is effective at reducing the major SM backgrounds, leading to a 5 σ (3 σ ) discovery reach for $$ m\left({\tilde{\upchi}}_2^0\right) $$ m χ ˜ 2 0 < 180 (260) GeV, and a projected 95% confidence level exclusion region that covers $$ m\left({\tilde{\upchi}}_2^0\right) $$ m χ ˜ 2 0 up to 385 GeV, parameter space that is currently unconstrained by other experiments.
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Effective Leptophilic WIMPs at the e+e− collider
A bstract We consider higher-dimensional effective (EFT) operators consisting of fermion dark matter (DM) connecting to Standard Model (SM) leptons upto dimension six. Considering all operators together and assuming the DM to undergo thermal freeze-out, we find out relic density allowed parameter space in terms of DM mass ( m χ ) and New Physics (NP) scale (Λ) with one loop direct search constraints from XENON1T experiment. Allowed parameter space of the model is probed at the proposed International Linear Collider (ILC) via monophoton signal for both Dirac and Majorana cases, limited by the centre-of-mass energy $$ \sqrt{s} $$ s =1 TeV, where DM mass can be probed within $$ {m}_{\chi }<\frac{\sqrt{s}}{2} $$ m χ < s 2 for the pair production to occur and Λ > $$ \sqrt{s} $$ s for the validity of EFT framework.
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- Award ID(s):
- 1915093
- NSF-PAR ID:
- 10379619
- Date Published:
- Journal Name:
- Journal of High Energy Physics
- Volume:
- 2022
- Issue:
- 4
- ISSN:
- 1029-8479
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1007/JHEP04(2022)146
