arXiv subjects

Chengping Shen

Publications and source records attributed to Chengping Shen.

9 recordsLinked to original sources

arXiv2026

Exotic hadrons associated with $b$-quark

Compared to charmonium-like states, exotic hadrons associated with $b$-quark offer distinct advantages for exploring the nature of multiquark phenomena and the dynamics of the strong interaction. Due to the heavier bottom quark mass, theoretical calculations, particularly those based on effective field theories and potential models, tend to be more reliable and under better control in the bottomonium sector. With its clean $e^+e^-$ collision environment and high luminosity, the Belle and Belle II experiments are ideally suited to explore these exotic hadrons associated with $b$-quark, including $Z_b$, $X_b$, and $Y_b$ states, and charmonium-like states in $B$ decays. Utilizing the large proton--proton collision dataset, the LHCb experiment has conducted extensive investigations of heavy-flavor multiquark states through $B$ and $\Lambda_b$ decay channels. The relevant phenomenological interpretations are also reviewed.

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arXiv2024

Flavor Physics at the CEPC: a General Perspective

We discuss the landscape of flavor physics at the Circular Electron-Positron Collider (CEPC), based on the nominal luminosity outlined in its Technical Design Report. The CEPC is designed to operate in multiple modes to address a variety of tasks. At the $Z$ pole, the expected production of 4 Tera $Z$ bosons will provide unique and highly precise measurements of $Z$ boson couplings, while the substantial number of boosted heavy-flavored quarks and leptons produced in clean $Z$ decays will facilitate investigations into their flavor physics with unprecedented precision. We investigate the prospects of measuring various physics benchmarks and discuss their implications for particle theories and phenomenological models. Our studies indicate that, with its highlighted advantages and anticipated excellent detector performance, the CEPC can explore beauty and $\tau$ physics in ways that are superior to or complementary with the Belle II and Large-Hadron-Collider-beauty experiments, potentially enabling the detection of new physics at energy scales of 10 TeV and above. This potential also extends to the observation of yet-to-be-discovered rare and exotic processes, as well as testing fundamental principles such as lepton flavor universality, lepton and baryon number conservation, etc., making the CEPC a vibrant platform for flavor physics research. The $WW$ threshold scan, Higgs-factory operation and top-pair productions of the CEPC further enhance its merits in this regard, especially for measuring the Cabibbo-Kobayashi-Maskawa matrix elements, and Flavor-Changing-Neutral-Current physics of Higgs boson and top quarks. We outline the requirements for detector performance and considerations for future development to achieve the anticipated scientific goals.

hep-ex↗

arXiv2023

Status and Prospects of Exotic Hadrons at Belle II

In the past twenty years, many new hadrons that are difficult to be explained within the conventional quark model have been discovered in the quarkonium region, which are called exotic hadrons. Belle II experiment, as the next-generation $B$ factory, provides a good platform to explore them. The charmonium-like states can be produced at Belle II in several ways, such as $B$ meson decays, initial-state radiation processes, two-photon collisions, and double charmonium productions. The bottomonium-like states can be produced directly in $e^+e^-$ colliding energies at Belle II with low continuum backgrounds. Belle II plans to perform a high-statistics energy scan from the $B\bar B$ threshold up to the highest possible energy of 11.24 GeV to search for new $Y_b$ states with $J^{PC}$ = $1^{--}$, $X_b$ (the bottom counterpart of $\chi_{c1}(3872)$ (also known as $X(3872)$)), and partners of $Z_b$ states. In this paper, we give a mini-review on the status and prospects of exotic hadrons at Belle II.

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arXiv2020

TopoAna: A generic tool for the event type analysis of inclusive Monte-Carlo samples in high energy physics experiments

Inclusive Monte-Carlo samples are indispensable for signal selection and background suppression in many high energy physics experiments. A clear knowledge of the physics processes involved in the samples, including the types of processes and the number of processes in each type, is a great help to investigating signals and backgrounds. To help analysts obtain the physics process information from the truth information of the samples, we develop a physics process analysis program, TopoAna, with C++, ROOT, and LaTeX. The program implements the functionalities of component analysis and signal identification with many kinds of fine, customizable classification and matching algorithms. It tags physics processes in individual events accurately in the output root files, and exports the physics process information at the sample level clearly to the output plain text, tex source, and pdf files. Independent of specific software frameworks, the program is applicable to many experiments. At present, it has come into use in three $e^+e^-$ colliding experiments: the BESIII, Belle, and Belle II experiments. The use of the program in other similar experiments is also prospective.

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arXiv2020

Experimental review of the $Υ(1S,2S,3S)$ physics at $e^+e^-$ colliders and the LHC

The three lowest-lying $Υ$ states, i.e. $Υ(1S)$, $Υ(2S)$, and $Υ(3S)$, composed of $b\bar b$ pairs and below the $B\bar B$ threshold, provide a good platform for the researches of hadronic physics and physics beyond the Standard Model. They can be produced directly in $e^+e^-$ colliding experiments, such as CLEO, Babar, and Belle, with low continuum backgrounds. In these experiments, many measurements of the exclusive $Υ(1S)$ and $Υ(2S)$ decays into light hadrons, which shed light on the "80\% rule" for the Okubo-Zweig-Iizuka suppressed decays in the bottomonium sector, were carried out. Meanwhile, many studies of the charmonium and bottomonium productions in $Υ(1S,2S,3S)$ decays were performed, to distinguish different Quantum Chromodynamics (QCD) models. Besides, exotic states and new physics were also extensively explored in $Υ(1S,2S,3S)$ decays at CLEO, BaBar, and Belle. The $Υ(1S,2S,3S)$ states can also be produced in $pp$ collisions and in collisions involving heavy ions. The precision measurements of their cross sections and polarizations at the large hadron collider (LHC), especially in the CMS, ATLAS, and LHCb experiments, help to understand $Υ$ production mechanisms in $pp$ collisions. The observation of the sequential $Υ$ suppression in heavy ion collisions at CMS is of great importance for verifying the quark-gluon plasma predicted by QCD. In this article, we review the experimental results on $Υ(1S,2S,3S)$ at $e^+e^-$ colliders and the LHC, and summarize their prospects at Belle II and the LHC.

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arXiv2018

PHOTON-2017 conference proceedings

This document collects the proceedings of the PHOTON 2017 conference ("International Conference on the Structure and the Interactions of the Photon", including the 22th "International Workshop on Photon-Photon Collisions", and the "International Workshop on High Energy Photon Colliders") held at CERN (Geneva) in May 2017. The latest experimental and theoretical developments on the topics of the PHOTON conference series are covered: (i) $γ\,γ$ processes in e$^+$e$^-$, proton-proton (pp) and nucleus-nucleus (AA) collisions at current and future colliders, (ii) $γ$-hadron interactions in e$^\pm$p, pp, and AA collisions, (iii) final-state photon production (including Standard Model studies and searches beyond it) in pp and AA collisions, and (iv) high-energy $γ$-ray astrophysics. These proceedings are dedicated to the memory of Maria Krawczyk.

hep-ph↗

arXiv2014

Charmonium and light hadron spectroscopy

In this report I review some results on the charmonium and light hadron spectroscopy mainly from BESIII and Belle experiments. For the charmonium, the contents include the observation of $ψ(4040)/ψ(4160) \to η\jpsi$, the measurements of the $η_c/η_c(2S)$ resonance parameters and their decays, the evidence of the $ψ_2(1^3D_2)$ state in the $χ_{c1}γ$ mass spectrum. For the light hadron spectroscopy, the contents include the $X(1835)$ research in $e^+e^- \to \jpsi + X(1835)$ and $γγ\to η' π^+ π^-$ processes, and the analysis of the $ηη$, $ωϕ$, $ϕϕ$ and $ωω$ mass spectra in low mass region.

hep-ex↗

arXiv2014

Test of QCD at large $Q^2$ with exclusive hadronic processes

My report consists of two parts: (1). Using samples of 102 million $Υ(1S)$ and 158 million $Υ(2S)$ events at Belle, we study 17 exclusive hadronic decays of these two bottomonium resonances to some Vector-Pseudoscalar (VP), Vector-Tensor (VT) and Axial-vector-Pseudoscalar (AP) processes and their final states. Branching fractions are measured for all the processes. The ratios of the branching fractions of $Υ(2S)$ and $Υ(1S)$ decays into the same final state are used to test a perturbative QCD (pQCD) prediction for OZI-suppressed bottomonium decays. (2). Using data samples of 89 fb$^{-1}$, 703 fb$^{-1}$, and 121 fb$^{-1}$ collected at center-of-mass (CMS) energies 10.52, 10.58, and 10.876~GeV, respectively, we measure the cross sections of $e^+e^- \to ωπ^0$, $K^{\ast}(892)\bar{K}$, and $K_2^{\ast}(1430)\bar{K}$. The energy dependence of the cross sections is presented.

hep-ex↗

arXiv2010

Recent results from BESIII

Using about $226\times 10^6$ $\jpsi$ events and $106\times 10^6$ $ψ^{\prime}$ events collected with the BESIII detector at the BEPCII $e^+e^-$ collider, the Dalitz plot of $\etap \to ηπ^+ π^-$ decay is studied, the direct measurement of $a^{0}_{0}(980)-f_{0}(980)$ mixing is performed, $X(2120)$ and $X(2370)$ are observed in the $π^+π^-η^\prime$ invariant mass spectrum, $ψ^{\prime}\toγπ^0$ and $ψ^{\prime}\toγη$ are observed for the first time, and the decays $χ_{cJ}\toγV$ ($V=ϕ$, $ρ^0$, $ω$) are studied.

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