We investigate the potential of the Compact Muon Solenoid (CMS) detector at the Large Hadron Collider (LHC) to discriminate between two theoretical models predicting anomalous events with jets and large missing transverse energy, minimal supersymmetry and Little Higgs with T Parity. We focus on a simple test case scenario, in which the only exotic particles produced at the LHC are heavy color-triplet states (squarks or T-quarks), and the only open decay channel for these particles is into the stable missing-energy particle (neutralino or heavy photon) plus a quark. We find that in this scenario, the angular and momentum distributions of the observed jets are sufficient to discriminate between the two models with a few inverse fb of the LHC data, provided that these distributions for both models and the dominant Standard Model backgrounds can be reliably predicted by Monte Carlo simulations.
The existence of new coloured states with spin one-half, i.e. extra-quarks, is a striking prediction of various classes of new physics models. Should one of these states be discovered during the 13 TeV runs of the LHC or at future high energy hadron colliders, understanding its properties will be crucial in order to shed light on the underlying model structure. Depending on the extra-quarks quantum number under SU(2)L, their coupling to Standard Model quarks and bosons have either a dominant left- or right-handed chiral component. By exploiting the polarisation properties of the top quarks ari…
As no evidence for classic WIMP-based signatures of dark matter have been found at the LHC, several phenomenological studies have raised the possibility of accessing a strongly-interacting dark sector through new collider-event topologies. If dark mesons exist, their evolution and hadronization procedure are currently little constrained. They could decay promptly and result in QCD-like jet structures, even though the original decaying particles are dark sector ones; they could behave as semi-visible jets; or they could behave as completely detector-stable hadrons, in which case the final state…
Two-Stage Machine Learning Strategy for Scalar and Vector Leptoquark Discrimination at the LHC
Universidad Autónoma de Madrid（马德里自治大学）；Centro Atómico Bariloche, Instituto Balseiro and CONICET（巴里洛切原子中心巴尔塞罗研究所与阿根廷国家科学研究委员会）；IFLP, CONICET - Dpto. de Física, Universidad Nacional de La Plata（拉普拉塔国立大学物理系与阿根廷国家科学研究委员会拉普拉塔理论物理研究所）
Operator Identification in Charged Lepton-Flavor Violation: Global EFT Analysis with RG Evolution, Polarization Observables, and Bayesian Model Discrimination at Future Colliders
Universidad Técnica Federico Santa María（弗雷德里克·萨马利亚技术大学）；Millennium Institute for Subatomic Physics at the High-Energy Frontier (SAPHIR)（高能前沿亚原子物理千年研究所（SAPHIR））
The Large Hadron Collider witnesses the highest ever production cross-section of double parton scattering processes. The production of a Z-boson along with two jets from double parton scattering provides a unique opportunity to explore the kinematics of double parton scattering processes and their dependence on the scale of the second interaction. The experimental measurement of this process is largely contaminated by Z + jets production from single parton scattering. In this paper, fragmentation properties of a jet are explored to check their sensitivity towards double parton scattering. The …
Discrimination of New Physics Models with the International Linear Collider
大型强子对撞机（LHC）有望提供TeV量级的新物理信号，这可能涉及WIMP暗物质候选者的产生。国际线性对撞机（ILC）将对这些信号进行分类，并引导我们在TeV尺度上找到新物理学的可行模型。本文以惰性Higgs模型、超对称Higgs模型和具有T宇称的最小Higgs模型为例，讨论了ILC如何鉴别新的物理模型。这些模型预测了具有不同自旋的暗物质粒子，分别为0、1/2和1，因此包括代表性的场景。具体来说，我们专注于对生产过程，e+e-> chi+chi- -> chi 0 chi 0 W +W-，其中chi 0和chi+-是WIMP暗物质和一个新的带电粒子在这些模型中预测。然后，我们评估如何准确地确定这些新粒子的性质，可以在ILC和证明，ILC是能够识别新的带电粒子的自旋和歧视这些模型。
Velocity distribution of dark matter is assumed to be isotropic in most cases, however, anisotropy is suggested in some simulations. Directional direct detection of dark matter is a hopeful way to discriminate the anisotropy of dark matter velocity distribution. We simulate the dark matter and target scattering in the directional direct detection, and investigate conditions required to discriminate the anisotropy. If dark matter mass is known, $O(10^3)-O(10^4)$ events are required for the discrimination if the dark matter mass is known by other experiments. We also study the case that the dark…
