arXiv subjects

Yoxara Villamizar

Publications and source records attributed to Yoxara Villamizar.

4 recordsLinked to original sources

arXiv2026

Photons, jets and missing momentum from a two-vector dark sector

We investigate the LHC phenomenology of a vector dark-sector effective theory containing two neutral massive vector states, both odd under a dark-parity symmetry. The lightest state is stable and provides a dark-matter candidate, while the leading interactions with the Standard Model arise from dimension-six operators involving the hypercharge field strength. In the prompt-decay regime considered in this work, the heavier state can decay radiatively, leading to a $γ+\text{jets}+E_T^{\text{miss}}$ signature when the two dark vectors are produced in association with QCD radiation. We study this topology at the LHC through a cut-based analysis, comparing an inclusive missing-transverse-momentum selection with a three-bin strategy that retains coarse shape information. The binned analysis is found to substantially improve the expected reach and probes regions of the parameter space compatible with the observed relic abundance in the standard freeze-out scenario. We also discuss the freeze-in interpretation and the limitations associated with the EFT description at high masses.

hep-ph↗

arXiv2025

Search for sub-GeV Scalars in $e^+e^-$ collisions

Light scalars that couple to leptons are common figures in beyond the Standard Model endeavors. Considering a scalar that has universal and couplings to leptons only, we compute this leptophilic scalar contribution to the $e^{-}e^{+} \rightarrow τ^{+}τ^{-} S $ production cross section with $S \rightarrow e^{+}e^{-}(μ^{+}μ^{-})$. We later compare the expected signal with recent data from the BELLE collaboration collected near the resonance $Υ(4S)$ with $\mathcal{L}=626 fb^{-1}$ of integrated luminosity to place limits on the couplings-mass plane for the $4$~MeV-$6.5$~GeV mass range. We then extended this analysis to a more general one $e^{-}e^{+} \rightarrow {\ell}^{+}{\ell}^{-} S$ production cross section where $\ell=e,μ,τ$ with $S \rightarrow e^{+}e^{-}(μ^{+}μ^{-})$, showing that BELLE constitutes an excellent laboratory for light scalars, where can be derived constraints stronger than those derived stemming from the g-2 of the electron or muon.

hep-ph↗

arXiv2024

SModelS v3: Going Beyond Z2 Topologies

SModelS is a public tool for fast reinterpretation of LHC searches for new physics based on a large database of simplified model results. While previous versions were limited to models with a Z2-type symmetry, such as R-parity conserving supersymmetry, version 3 can now handle arbitrary signal topologies. To this end, the tool was fully restructured and now relies on a graph-based description of simplified model topologies. In this work, we present the main conceptual changes and novel features of SModelS v3, together with the inclusion of new experimental searches for resonant production of spin-1 and spin-0 mediators with decays to quarks or to dark matter. Applying these results to a model containing two mediators, we discuss the interplay of resonance and missing energy searches, and the model's coverage by the currently available simplified model results.

hep-ph↗

arXiv2019

Doubly Charged Scalar at the High-Luminosity and High-Energy LHC

Doubly charged scalars are common figures in several beyond the Standard Model studies, especially those related to neutrino masses. In this work, we estimate the High-Luminosity (HL-LHC) and High-Energy LHC (HE-LHC) sensitivity to doubly charged scalars assuming they decay promptly and exclusively into charged leptons. Our study focuses on the fit to the same-sign dilepton mass spectra and it is based on proton-proton collisions at $13$ TeV, $14$ TeV and $27$ TeV with integrated luminosity of $\mathcal{L}=139 fb^{-1}, 3 $ab$^{-1}$ and $15$ab$^{-1}$. We find that HL-LHC may probe doubly charged scalars masses up to $2.3$ TeV, whereas HE-LHC can impressively probe masses up to $3$ TeV, conclusively constituting a complementary and important probe to signs of doubly charged scalars in lepton flavor violation decays and lepton-lepton colliders.

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