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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Strange Stars in the Vector Interaction Enhanced Bag Model
The vector interaction enhanced Bag model (vBag) for dense quark matter extends the commonly used thermodynamic Bag model (tdBag) by incorporating effects of dynamical chiral symmetry breaking (D χ SB) and vector repulsion. Motivated by the suggestion that the stability of strange matter is in tension with chiral symmetry breaking (D χ SB) we examine the parameter space for its stability in the vBag model in this work. Assuming the chiral transition occurs at sufficiently low density, we determine the stability region of strange matter as a function of the effective Bag constant and the vector coupling. As an astrophysical application, we construct contours of maximum mass M max and radius at maximum mass R max in this region of parameter space. We also study the stability of strange stars in the vBag model with maximum mass in the 2 M ⊙ range by computing the spectrum of radial oscillations, and comparing to results from the tdBag model, find some notable differences.
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- Award ID(s):
- 1913693
- NSF-PAR ID:
- 10174237
- Date Published:
- Journal Name:
- Particles
- Volume:
- 2
- Issue:
- 4
- ISSN:
- 2571-712X
- Page Range / eLocation ID:
- 447 to 456
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/particles2040027
