arXiv subjects

Xunwu Zuo

Publications and source records attributed to Xunwu Zuo.

4 recordsLinked to original sources

arXiv2026

Projections of H$\to\tau\tau$ cross-section at FCC-ee

The Future Circular Collider (FCC) stands at the forefront of the European Strategy for Particle Physics as the future flagship project at CERN. The H$\to\tau\tau$ decay, featuring a large branching ratio, clean identification in the FCC-ee environment, and the possibility to reconstruct polarization information, is an excellent channel to measure Higgs boson properties. This work shows the expected precision for the H$\to\tau\tau$ cross-section measurement at the FCC-ee in the ZH production mechanism at $\sqrt{s}=$240 GeV and $\sqrt{s}=$365 GeV, as well as via the vector boson fusion process at $\sqrt{s}=$365 GeV. Furthermore, we explore and evaluate a set of methods for reconstructing tau decays. These techniques are critical for unlocking the full physics potential of the FCC-ee and for improving the understanding of tau-related observables in both Standard Model measurements and New Physics searches. The results obtained significantly enhance the FCC-ee outlook in the H$\to\tau\tau$ channel, improving it by at least an order of magnitude compared to the current sensitivity of measurements' performance at the LHC.

hep-ph↗

arXiv2024

Searching for type I seesaw mechanism in a two Heavy Neutral Leptons scenario at FCC-ee

This paper investigates the search for heavy neutral leptons (HNL) in the type I seesaw mechanism at the Future Circular Collider in its $e^+e^-$ stage (FCC-ee), considering a luminosity of 125 ab$^{-1}$ collected at $\sqrt{s}=$91.2 GeV. The study examines two generations of heavy neutral leptons produced in association with Standard Model (SM) neutrinos and decaying to a purely leptonic final state. This theoretical framework can explain neutrino oscillations and other open questions of the SM, providing a broader perspective on the relevance of this experimental search. The analysis is performed using a fast simulation of the IDEA detector concept to study potential HNL interactions at the FCC-ee. The sensitivity contours are obtained from a selection of kinematic variables aimed at improving the signal-to-background ratio for the prompt production case. In the case of long-lived HNLs, the background can be almost fully eliminated by exploiting their displaced decay vertices. The study shows that the FCC-ee has a significant sensitivity to observing these objects in a region of the phase space not accessible by other experiments.

hep-ph↗

arXiv2024

Prospects for $B_c^+$ and $B^+\to τ^+ ν_τ$ at FCC-ee

The prospects are presented for precise measurements of the branching ratios of the purely leptonic $B_c^+ \to τ^+ ν_τ$ and $B^+ \to τ^+ ν_τ$ decays at the Future Circular Collider (FCC). This work is focused on the hadronic $τ^{+} \to π^+ π^+ π^- \barν_τ$ decay in both $B_c^+ \to τ^+ ν_τ$ and $B^+ \to τ^+ ν_τ$ processes. Events are selected with two Boosted Decision Tree algorithms to optimise the separation between the two signal processes as well as the generic hadronic $Z$ decay backgrounds. The range of the expected precision for both signals are evaluated in different scenarios of non-ideal background modelling. This paper demonstrates, for the first time, that the $B^+ \to τ^+ ν_τ$ decay can be well separated from both $B_c^+ \to τ^+ ν_τ$ and generic $Z\to b\bar{b}$ processes in the FCC-ee collision environment and proposes the corresponding branching ratio measurement as a novel way to determine the CKM matrix element $|V_{ub}|$. The theoretical impacts of both $B^+ \to τ^+ ν_τ$ and $B_c^+ \to τ^+ ν_τ$ measurements on New Physics cases are discussed for interpretations in the generic Two-Higgs-doublet model and leptoquark models.

hep-ex↗

arXiv2023

The Potential of a TeV-Scale Muon-Ion Collider

We propose the development of a novel muon-proton and muon-nucleus collider facility at the TeV scale that is capable of performing precision deep inelastic scattering measurements in new regimes and providing a rich program in nuclear and particle physics. Such a facility could seed, or leverage, the development of a muon-antimuon collider and make use of the existing hadron accelerator infrastructure when sited at a facility such as Brookhaven National Laboratory, Fermilab, or CERN. We discuss the possible energy and luminosity design parameters for several collider configurations, and illustrate the science potential with several studies on deep inelastic scattering kinematics, Higgs and vector boson production, top quark production, and beyond Standard Model leptoquark production. Detector design considerations and a possible road map toward development are also given.

hep-ex↗